cleanup

- new options:
  -l, --list-dictionaries: list dictionaries
  -n, --no-similar-chars:  avoid similar chars (0O/1l etc..)
- remove dead code

.gitignore

@@ -0,0 +1,11 @@
+.ccls*
+/*.c
+/*.sh
+/COPYING.*
+/license-*
+/LICENSE.*
+/test/
+/todo/
+/c/lib/
+/c/obj/
+compile_commands.json

README.md

@@ -3,8 +3,6 @@
 #### bash
 
 - **trans.sh**: a [linguee.com](https://linguee.com) based command-line translator.
-
 - **sync.sh**: a rsync/ssh backup tool.
     - **sync-conf-example.sh**: configuration example.
-
-- **dup-live-disk.sh**: copy live partitions to backup disk.
+- **dup-live-disk.sh**: duplicate (possibly live) disk partitions.

bash/README.md

@@ -0,0 +1,11 @@
+### Some GNU/Linux tools, for fun...
+
+
+#### bash
+
+- [**trans.sh**](trans.sh): a [linguee.com](https://linguee.com) based command-line translator.
+- [**sync.sh**](sync.sh): a rsync/ssh backup tool.
+    - [**sync-conf-example.sh**](share/sync/sync-conf-example.sh): configuration example.
+- [**dup-live-disk.sh**](dup-live-disk.sh): duplicate (possibly live) disk partitions.
+- [**gen-password.sh**](gen-password.sh): a password generator
+    - [**share/gen-password**](share/gen-password): [diceware](https://en.wikipedia.org/wiki/Diceware)-like word lists.

bash/dup-live-disk.sh

@@ -1,73 +1,675 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
-# dup-live-disk.sh - duplicate live system partitions on new disk.
+# dup-live-disk.sh - duplicate (possibly live) system partitions
 #
-# (C) Bruno Raoult ("br"), 2007-2021
-# Licensed under the Mozilla Public License (MPL) version 2.0.
+# (C) Bruno Raoult ("br"), 2007-2022
+# Licensed under the GNU General Public License v3.0 or later.
 # Some rights reserved. See COPYING.
 #
-# You should have received a copy of the Mozilla Public License along with this
-# program.  If not, see <https://www.mozilla.org/en-US/MPL>
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
 #
-# SPDX-License-Identifier: MPL-2.0 <https://spdx.org/licenses/MPL-2.0.html>
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
 #
-# This script will not work for all situations, I strongly suggest you
-# don't use it if you don't *fully* understand it.
+#%MAN_BEGIN%
+# NAME
+#       dup-live-disk.sh - duplicate (possibly live) system partitions
+#
+# SYNOPSIS
+#       dup-live-disk.sh [OPTIONS] [SRC] DST
+#
+# DESCRIPTION
+#       Duplicate SRC disk partitions to same structured DST disk ones.
+#       if SRC is omitted, the running system disk (where root partition
+#       resides) will be used.
+#       Both SRC and DST *must* have same partition base LABELs - as 'LABEL'
+#       field for lsblk(1) and blkid(1), with an ending character (unique per
+#       disk) to differentiate them.
+#       For example, if partitions base labels are 'root', 'export', and 'swap',
+#       SRC disk the ending character '1' and DST disk the character '2', SRC
+#       partitions must be 'root1', 'export1, and 'swap1', and DST partitions
+#       must be 'root2', 'export2, and 'swap2'.
+#
+# OPTIONS
+#       -a, --autofs=DIR
+#          Use DIR as autofs "LABEL-based" automount. See AUTOFS below. Default
+#          is /mnt.
+#
+#       -c, --copy=ACTION
+#          ACTION can be 'yes' (all eligible partitions will be copied), 'no'
+#          (no partition will be copied), or 'ask'. Default is 'Ask'.
+#          See ACTIONS below.
+#
+#       -d, --dry-run
+#          Dry-run: nothing will be really be written to disk. This option
+#          0verrides any of '--yes', '--copy', '--fstab', '--grub', and
+#          '--mariadb' options.
+#
+#       -f, --fstab=ACTION
+#          ACTION ('yes', 'no', or 'ask') defines whether fstab should be
+#          adjusted on destination root partition. Default is 'ask'.
+#          /etc/fstab/LABEL must exist on source root partition. LABEL is the
+#          partition LABEL of destination root disk.
+#          See ACTIONS below.
+#
+#       -g, --grub=ACTION
+#          ACTION ('yes', 'no', 'ask') defines if grub should be installed on
+#          destination disk). Default is 'ask'.
+#          Warning: Only works if root partition contains all necessary files
+#          for grub: /boot, /usr, etc...
+#          See ACTIONS below.
+#
+#       -h, --help
+#          Display short help and exit.
+#
+#       -m, --man
+#          Display a "man-like" description and exit.
+#
+#       -M, --mariadb=ACTION
+#          ACTION may be 'yes', 'no', or 'ask', which indicates whether mysql
+#          or mariadb should be stopped before effective partition copies, and
+#          restarted after.
+#          See ACTIONS below.
+#
+#       -n, --no
+#          Will answer 'no' to any question asked to user.
+#
+#       -r, --root=PARTNUM
+#          Mandatory if SRC is provided, forbidden otherwise.
+#          PARTNUM is root partition number on SRC disk.
+#
+#       -y, --yes
+#          Will answer 'yes' to any question asked to user.
+#
+# ACTIONS
+#       Before writing anything, of if something unexpected happens, the
+#       program may ask to proceed. User may answer 'yes', 'no', or 'quit'.
+#       Options --yes, and --no will default respectively to 'yes' and 'no',
+#       default is to ask.
+#       Options '--copy', '--fstab', and '--grub' (which can take the values
+#       'yes', 'no', and 'ask') can override the specific action for copying
+#       partitions, adjusting destination fstab file, and
+#       installing grub on destination disk.
+#
+# EXAMPLES
+#       Copy sda to sdb, root partition is partition 1 (sda1/sdb1) on both
+#       disks. The user will be asked for any action (partition copy, grub,
+#       etc...)
+#       $ sudo dup-live-disk.sh --root 1 sda sdb
+#
+#       Copy live disk (all partitions of current / partition disk) to sdb.
+#       The user will be asked for any action (partition copy, grub, etc...)
+#       $ sudo dup-live-disk.sh sdb
+#
+#       Copy live disk (all partitions of current / partition disk) to sdb.
+#       All valid partitions will be copied, and grub installed on sdb.
+#       $ sudo dup-live-disk.sh --yes sdb
+#
+#       Do not copy partitions, only install grub on sdb.
+#       $ sudo ./dup-live-disk.sh --copy=no --grub=yes sdb
+#       or
+#       $ sudo ./dup-live-disk.sh --no --grub=yes sdb
+#
+# AUTOFS
+#       This script relies on autofs to mount partitions according to partitions
+#       LABELS. See autofs(5) and auto.master(5) for more details.
+#       For example, the following will mount partitions withs LABELS 'root1',
+#       'root2' in /mnt/hd/root1 and /mnt/hd/root2, simply when we try to access
+#       the directories (for example with 'ls /mnt/hd/root1') :
+#
+#       # in file /etc/auto.master
+#       /mnt/hd   /etc/auto.hd              --timeout 60 --ghost
+#
+#       # in file /etc/auto.hd
+#       *         -fstype=auto,defaults     :LABEL=&
+#
+#       This script uses /mnt as default autofs directory. In fact, /mnt contains
+#       symbolic links to different disk labels :
+#
+#       $ ls -l /mnt/root?
+#       lrwxrwxrwx 1 root root 8 Oct 10  2020 /mnt/root1 -> hd/root1/
+#       lrwxrwxrwx 1 root root 8 May 25  2018 /mnt/root2 -> hd/root2/
+#
+#       It means that accessing /mnt/root1 will automagically mount /mnt/hd/root1.
+#       With the maps above, and without the /mnt symlinks, it is possible to
+#       use '--autofs=/mnt/hd' to directly use the automounter map.
+#
+# BUGS
+#       * Cannot generate grub with a separate /boot partition.
+#       * This script will not work for all situations, I strongly suggest you
+#         don't use it if you don't *fully* understand it.
+#       * Extended attributes are not preserved (easy fix, but I cannot test)
+#
+# TODO
+#       * Log levels
+#%MAN_END%
 
-# dest device (used for grub)
-DSTDISK=/dev/sdb
+# command line
+SCRIPT="$0"
+CMD="${0##*/}"
+export LC_ALL=C
 
-# partitions suffixes, for source and destination partitions.
-# For example, if we want to copy XX partition, source partition will be
-# /mnt/XX${SRCNUM}, and destination will be /mnt/XX${DSTNUM}
-SRCNUM=2
-DSTNUM=1
+# valid filesystems
+# shellcheck disable=2034
+VALIDFS=(ext3 ext4 btrfs vfat reiserfs xfs zfs)
 
-# array of partitions to copy
-TO_COPY=(root export EFI)
+man() {
+    sed -n '/^#%MAN_BEGIN%/,/^#%MAN_END%$/{//!s/^#[ ]\{0,1\}//p}' "$SCRIPT" | more
+}
 
-# An alternative to SRCNUM, DSTNUM, and TO_COPY variables would be to have
-# an array containing src and destination partitions:
-#   (partsrc1 partdst1 partsrc2 partdst2 etc...)
-# example:
-# TO_COPY=(root2 root1 export2 export1)
-# declare -i i
-# for ((i=0; i<${#TO_COPY[@]}; i+=2)); do
-#     SRC=${#TO_COPY[$i]}
-#     DST=${#TO_COPY[$i + 1]}
-# etc...
+usage() {
+    cat <<_EOF
+Usage: $CMD [OPTIONS] [SRC] DST
+Duplicate SRC (or live system) disk partitions to DST disk partitions.
 
-# where we will configure/install grub: mount point, device
-GRUB_ROOT=/mnt/root${DSTNUM}
-GRUB_DEV=/dev/$(lsblk -no pkname /dev/disk/by-label/root${DSTNUM})
+Options:
+      -a, --autofs=DIR     autofs 'LABEL-based' directory. Default is '/mnt'.
+      -c, --copy=ACTION    do partitions copies (ACTION='yes', 'no', 'ask).
+                           Default is 'ask'
+      -d, --dry-run        dry-run: nothing will be written to disk
+      -f, --fstab=ACTION   adjust fstab on destination disk ('yes', 'no',
+                           'ask'). Default is 'ask'
+      -g, --grub=ACTION    install grub on destination disk ('yes', 'no',
+                           'ask'). Default is 'ask'
+      -h, --help           this help
+      -m, --man            display a "man-like" page and exit
+      -M, --mariadb=ACTION stop and restart mysql/mariadb server before and
+                           after copies ('yes', 'no', 'ask'). Default is 'ask'
+      -n, --no             Will answer 'no' to any question
+      -r, --root=PARTNUM   root partition number on SRC device
+                           mandatory if and only if SRC is provided
+      -y, --yes            Will answer 'yes' to any question
 
-# we will use ".rsync-disk-copy" files to exclude files/dirs
-RSYNCOPTS="-axH --delete --delete-excluded"
-FILTER=--filter="dir-merge .rsync-disk-copy"
+SRC and DST have strong constraints on partitions schemes and naming.
+Type '$CMD --man' for more details
+_EOF
+    return 0
+}
 
-# stop what could be problematic (databases, etc...)
-systemctl stop mysql
+# log function
+# parameters:
+# -l, -s: long, or short prefix (default: none). Last one is used.
+# -t: timestamp
+# -n: no newline
+log() {
+    local timestr="" prefix="" opt=y newline=y
+    while [[ $opt = y ]]; do
+        case $1 in
+            -l) prefix=$(printf "*%.s" {1..30});;
+            -s) prefix=$(printf "*%.s" {1..5});;
+            -n) newline=n;;
+            -t) timestr=$(date "+%F %T%z - ");;
+            *) opt=n;;
+        esac
+        [[ $opt = y ]] && shift
+    done
+    [[ $prefix != "" ]] && printf "%s " "$prefix"
+    printf "%s" "$timestr"
+    # shellcheck disable=SC2059
+    printf "$@"
+    [[ $newline = y ]] && printf "\n"
+    return 0
+}
 
-# partitions copy
-for part in ${TO_COPY[@]}; do
-    SRCPART=/mnt/${part}${SRCNUM}/
-    DSTPART=/mnt/${part}${DSTNUM}
+# prints out and run (maybe) a command.
+echorun_maybe() {
+    if [[ "$DRYRUN" == 'yes' ]]; then
+        log "dry-run: %s" "$*"
+    else
+        log "%s" "$*"
+        "$@"
+    fi
+}
 
-    echo copy from $SRCPART to $DSTPART
-    echo -n "press a key to continue..."
-    read -r key
-    echo rsync ${RSYNCOPTS} "$FILTER" "$SRCPART" "$DSTPART"
-    rsync ${RSYNCOPTS} "$FILTER" "$SRCPART" "$DSTPART"
+yesno() {
+    local reason answer
+
+    # shellcheck disable=SC2059
+    printf -v reason "*** $1 [y/n/q] ? " "${@:2}"
+
+    while true; do
+        if [[ $YESNO =~ ^(yes|no)$ ]]; then
+            answer="$YESNO"
+            # shellcheck disable=SC2059
+            printf "$reason%s\n" "$answer"
+        else
+            read -p "$reason" -r answer
+        fi
+        case "${answer,,}" in
+            y|yes) return 0
+                   ;;
+            n|no) return 1
+                  ;;
+            q|quit) printf "Aborting...\n"
+                    exit 1
+        esac
+    done
+}
+
+# mariadb start/stop
+mariadb_maybe_stop() {
+    [[ $MARIADBSTOPPED == yes ]] && return 0
+    if systemctl is-active --quiet mysql; then
+        if [[ $MARIADB == ask ]]; then
+            if yesno "Stop MariaDB/MySQL"; then
+               MARIADB=yes
+            else
+               MARIADB=no
+            fi
+        fi
+        if [[ $MARIADB == no ]]; then
+            log "Warning: MariaDB/MySQL is running, database corruption possible on DEST disk."
+            return 0
+        fi
+        echorun_maybe systemctl stop mariadb
+        # bug if script stops here
+        MARIADBSTOPPED=yes
+    else
+        log "MariaDB/MySQL is inactive."
+    fi
+}
+
+mariadb_maybe_start() {
+    if [[ $MARIADB == yes && $MARIADBSTOPPED == yes ]]; then
+        #log -n "restarting mariadb/mysql... "
+        echorun_maybe systemctl start mariadb
+        MARIADBSTOPPED=no
+        #log "done."
+    fi
+}
+
+error_handler() {
+    local ERROR=$2
+    log "FATAL: Error line $1, exit code $2. Aborting."
+    exit "$ERROR"
+}
+trap 'error_handler $LINENO $?' ERR SIGHUP SIGINT SIGTERM
+
+exit_handler() {
+    local mnt
+
+    # log "exit handler (at line $1)"
+    mariadb_maybe_start
+    if [[ -n "$DSTMNT" ]] && mountpoint -q "$DSTMNT"; then
+        for mnt in "$DSTMNT"/{dev,proc,sys}; do
+            if mountpoint -q "$mnt"; then
+                # https://unix.stackexchange.com/questions/693346
+                if ! echorun_maybe umount "$mnt"; then
+                    echorun_maybe umount --lazy "$mnt"
+                fi
+            fi
+        done
+    fi
+}
+trap 'exit_handler $LINENO' EXIT
+
+# check_block_device - check a file system device
+# $1: device description
+# $2: more ('w' for writable)
+# $3: device
+check_block_device() {
+    local devtype="$1"
+    local mode="$2"
+    local dev="$3"
+
+    if [[ ! -b "$dev" ]]; then
+        log "$CMD: $devtype '$dev' is not a block device."
+        exit 1
+    fi
+    if [[ ! -r "$dev" ]]; then
+        log "$CMD: $devtype '$dev' is not readable."
+        exit 1
+    fi
+    if [[ $mode = "w" && ! -w "$dev" ]]; then
+        log "$CMD: $devtype '$dev' is not writable."
+        exit 1
+    fi
+    return 0
+}
+
+# check that /etc/fstab.DESTLABEL exists in SRC disk.
+check_fstab() {
+    local etc="${AUTOFS_DIR}/$SRCROOTLABEL/etc"
+    local fstab="fstab.$DSTROOTLABEL"
+    #if [[ "$FSTAB" != no ]]; then
+    if [[ ! -f "$etc/$fstab" ]]; then
+        FSTAB=no
+        log "Warning: No target fstab (%s) on SRC disk" "$etc/$fstab"
+    else
+        log "Info: Found target fstab (%s) in SRC root partition (%s)." "$fstab" "$etc"
+    fi
+    return 0
+}
+
+fix_fstab() {
+    local fstab="${AUTOFS_DIR}/$DSTROOTLABEL/etc/fstab"
+
+    #[[ ! -f "$fstab" ]] && log "Warning: DST fstab will be wrong !" && FSTAB=no
+    if [[ "$FSTAB" == ask ]]; then
+        yesno "Link %s to %s" "$fstab.$DSTROOTLABEL" "$fstab" && FSTAB=yes || FSTAB=no
+    fi
+    if [[ "$FSTAB" == no ]]; then
+        log "Warning: DST fstab will be *wrong*, boot is compromised"
+    else
+        echorun_maybe ln -f "$fstab.$DSTROOTLABEL" "$fstab"
+    fi
+    return 0
+}
+
+# check if $1 is in array $2 ($2 is by reference)
+in_array() {
+    local elt=$1 i
+    local -n arr=$2
+    for ((i=0; i<${#arr[@]}; ++i)); do
+        [[ ${arr[$i]} == "$elt" ]] && return 0
+    done
+    return 1
+}
+
+# source and destination devices, root partition
+SRC=""
+DST=""
+SRCROOT=""
+SRCROOTPARTNUM=""
+AUTOFS_DIR=/mnt
+
+DRYRUN=no                                         # dry-run
+FSTAB=ask                                         # adjust fstab
+GRUB=ask                                          # install grub
+COPY=ask                                          # do FS copies
+MARIADB=ask                                       # stop/start mysql/mariadb
+MARIADBSTOPPED=no                                 # mysql stopped ?
+YESNO=                                            # default answer
+ROOTCOPIED=no                                     # was root partition copied ?
+
+# short and long options
+SOPTS="a:c:df:g:hmM:nr:y"
+LOPTS="autofs:,copy:,dry-run,fstab:,grub:,help,man,mariadb:,no,root:,yes"
+
+if ! TMP=$(getopt -o "$SOPTS" -l "$LOPTS" -n "$CMD" -- "$@"); then
+    log "Use '$CMD --help' or '$CMD --man' for help."
+    exit 1
+fi
+
+eval set -- "$TMP"
+unset TMP
+
+while true; do
+    case "$1" in
+        '-a'|'--autofs')
+            AUTOFS_DIR="$2"
+            shift
+            ;;
+        '-c'|'--copy')
+            case "${2,,}" in
+                "no") COPY=no;;
+                "yes") COPY=yes;;
+                "ask") COPY=ask;;
+                *) log "invalid '$2' --copy flag"
+                   usage
+                   exit 1
+            esac
+            shift
+            ;;
+        '-d'|'--dry-run')
+            DRYRUN=yes
+            ;;
+        '-f'|'--fstab')
+            case "${2,,}" in
+                "no") FSTAB=no;;
+                "yes") FSTAB=yes;;
+                "ask") FSTAB=ask;;
+                *) log "invalid '$2' --fstab flag"
+                   usage
+                   exit 1
+            esac
+            shift
+            ;;
+        '-g'|'--grub')
+            case "${2,,}" in
+                "no") GRUB=no;;
+                "yes") GRUB=yes;;
+                "ask") GRUB=ask;;
+                *) log "invalid '$2' --grub flag"
+                   usage
+                   exit 1
+            esac
+            shift
+            ;;
+        '-h'|'--help')
+            usage
+            exit 0
+            ;;
+        '-m'|'--man')
+            man
+            exit 0
+            ;;
+        '-n'|'--no')
+            YESNO=no
+            ;;
+        '-M'|'--mariadb')
+            case "${2,,}" in
+                "no") MARIADB=no;;
+                "yes") MARIADB=yes;;
+                "ask") MARIADB=ask;;
+                *) log "invalid '$2' --mariadb flag"
+                   usage
+                   exit 1
+            esac
+            shift
+            ;;
+        '-r'|'--root')
+            SRCROOTPARTNUM="$2"
+            if ! [[ "$SRCROOTPARTNUM" =~ ^[[:digit:]]+$ ]]; then
+                log "$CMD: $SRCROOTPARTNUM must be a partition number."
+                exit 1
+            fi
+            shift
+            ;;
+        '--')
+            shift
+            break
+            ;;
+        '-y'|'--yes')
+            YESNO=yes
+            ;;
+        *)
+            usage
+            log 'Internal error!'
+            exit 1
+            ;;
+    esac
+    shift
 done
 
+# check if current user is root
+if (( EUID != 0 )); then
+    log "This script must be run as root... Aborting."
+    exit 1
+fi
+
+case "$#" in
+    1)
+        if [[ -n "$SRCROOTPARTNUM" ]]; then
+            log "$CMD: cannot have --root option for live system."
+            log "Use '$CMD --help' or '$CMD --man' for help."
+            exit 1
+        fi
+        # guess root partition disk name
+        SRCROOT=$(findmnt -no SOURCE -M /)
+        SRCROOTPARTNUM=${SRCROOT: -1}
+        SRC="/dev/"$(lsblk -no pkname "$SRCROOT")
+        DST="/dev/$1"
+        ;;
+    2)
+        if [[ -z "$SRCROOTPARTNUM" ]]; then
+            log "$CMD: missing --root option for non live system."
+            log "Use '$CMD --help' or '$CMD --man' for help."
+            exit 1
+        fi
+        SRC="/dev/$1"
+        SRCROOT="$SRC$SRCROOTPARTNUM"
+        DST="/dev/$2"
+        ;;
+    0)
+        log "Missing destination disk."
+        usage
+        exit 1
+        ;;
+    *)
+        usage
+        exit 1
+esac
+
+# check SRC and DST are different, find out their characteristics
+if [[ "$SRC" = "$DST" ]]; then
+    log "Fatal: destination and source disk are identical (%s)" "$SRC"
+    log "Use '%s --help' or '%s --man' for help." "$CMD" "$CMD"
+    exit 1
+fi
+check_block_device "source disk" r "$SRC"
+check_block_device "destination disk" w "$DST"
+check_block_device "source root partition" r "$SRCROOT"
+
+SRCROOTLABEL=$(lsblk -no label "$SRCROOT")
+# strip out last character
+ROOTLABEL=${SRCROOTLABEL%%?}
+
+# find out all partitions labels on SRC disk...
+# shellcheck disable=SC2207
+declare -a SRCLABELS=($(lsblk -lno  LABEL "$SRC"))
+# shellcheck disable=SC2206
+declare -a LABELS=(${SRCLABELS[@]%?})
+
+# ... and corresponding partition device and fstype
+declare -a SRCDEVS SRCFS SRC_VALID_FS
+for ((i=0; i<${#SRCLABELS[@]}; ++i)); do
+    TMP="${SRCLABELS[$i]}"
+    #log "TMP=%s" "$TMP"
+    TMPDEV=$(findfs LABEL="$TMP")
+    TMPFS=$(lsblk -no fstype "$TMPDEV")
+    log "found LABEL=$TMP DEV=$TMPDEV FSTYPE=$TMPFS"
+    SRCDEVS[$i]="$TMPDEV"
+    SRCFS[$i]="$TMPFS"
+    SRC_VALID_FS[$i]=n
+    in_array "$TMPFS" VALIDFS && SRC_VALID_FS[$i]=y
+    unset TMP TMPDEV TMPFS
+done
+
+# find out DST root partition
+# shellcheck disable=SC2207
+declare -a TMP_DSTLABELS=($(lsblk -lno  LABEL "$DST"))
+
+for maybe_root in "${TMP_DSTLABELS[@]}"; do
+    log "rootlabel=%s maybe=%s" "$ROOTLABEL" "$maybe_root"
+    if [[ $maybe_root =~ ^${ROOTLABEL}.$ ]]; then
+        log "Found destination root label: $maybe_root"
+        DSTROOTLABEL=$maybe_root
+        DSTCHAR=${DSTROOTLABEL: -1}
+        DSTROOT=$(findfs LABEL="$DSTROOTLABEL")
+        check_block_device "destination root partition" w "$DSTROOT"
+        break
+    fi
+done
+
+declare -a DSTLABELS DSTDEVS DSTFS DST_VALID_FS
+# Do the same for corresponding DST partitions labels, device, and fstype
+for ((i=0; i<${#LABELS[@]}; ++i)); do
+    TMP="${LABELS[$i]}$DSTCHAR"
+    log -n "Looking for [%s] label : " "$TMP"
+    if ! TMPDEV=$(findfs LABEL="$TMP"); then
+        log "not found."
+        exit 1
+    fi
+    TMPDISK=${TMPDEV%?}
+    log -n "DEV=%s DISK=%s " "$TMPDEV" "$TMPDISK"
+    if [[ "$TMPDISK" != "$DST" ]]; then
+        log "wrong disk (%s != %s)" "$TMPDISK" "$DST"
+        exit 1
+    fi
+    TMPFS=$(lsblk -no fstype "$TMPDEV")
+    log "FSTYPE=%s" "$TMPFS"
+    DSTLABELS[$i]="$TMP"
+    DSTDEVS[$i]="$TMPDEV"
+    DSTFS[$i]="$TMPFS"
+    DST_VALID_FS[$i]=n
+    in_array "$TMPFS" VALIDFS && DST_VALID_FS[$i]=y
+    unset TMP TMPDEV TMPFS
+done
+
+{
+    printf "DEV1 DEV2 LABEL1 LABEL2 FS1 FS2 SVALID\? DVALID\? ROOT\n"
+    for ((i=0; i<${#LABELS[@]}; ++i)); do
+        log -n "%s %s " "${SRCDEVS[$i]}" "${DSTDEVS[$i]}"
+        log -n "%s %s " "${SRCLABELS[$i]}" "${DSTLABELS[$i]}"
+        log -n "%s %s "  "${SRCFS[$i]}" "${DSTFS[$i]}"
+        log -n "%s %s "  "${SRC_VALID_FS[$i]}" "${DST_VALID_FS[$i]}"
+        [[ "$DSTROOTLABEL" == "${DSTLABELS[$i]}" ]] && log "*"
+        echo
+    done
+} | column -t
+
+check_fstab || exit 1
+
+FILTER=--filter="dir-merge .rsync-disk-copy"
+declare -a RSYNCOPTS=(-axH "$FILTER" --delete --delete-excluded)
+# copy loop
+for ((i=0; i<${#LABELS[@]}; ++i)); do
+    if [[ "${SRC_VALID_FS[$i]}" != y ]] || [[ "${DST_VALID_FS[$i]}" != y ]]; then
+        log "skipping label %s" "${LABELS[$i]}"
+        continue
+    fi
+    SRCPART="$AUTOFS_DIR/${SRCLABELS[$i]}/"
+    DSTPART="$AUTOFS_DIR/${DSTLABELS[$i]}"
+
+    #log -n "%s -> %s : " "$SRCPART" "$DSTPART"
+    #log "\t%s %s %s %s %s" rsync "${RSYNCOPTS}" "$FILTER" "$SRCPART" "$DSTPART"
+    copy="$COPY"
+    if [[ "$COPY" == 'ask' ]]; then
+        yesno "Copy $SRCPART to $DSTPART" && copy=yes || copy=no
+    fi
+    if [[ "$copy" == yes ]]; then
+        mariadb_maybe_stop
+        status=0
+        # shellcheck disable=SC2086
+        echorun_maybe rsync "${RSYNCOPTS[@]}" "$SRCPART" "$DSTPART" || status=$?
+        if (( status != 24 && status != 0 )); then
+            log -s "rsync error %d" "$status"
+            exit 1
+        fi
+
+        if [[ "$DSTROOTLABEL" == "${DSTLABELS[$i]}" ]]; then
+            ROOTCOPIED=yes
+            fix_fstab
+        fi
+    fi
+    #log ""
+done
+mariadb_maybe_start
+
 # grub install
-# mount virtual devices
-mount -o bind  /sys    ${GRUB_ROOT}/sys
-mount -o bind  /proc   ${GRUB_ROOT}/proc
-mount -o bind  /dev    ${GRUB_ROOT}/dev
+if [[ $GRUB == ask ]]; then
+    if ! yesno "install grub on %s (root label: %s)" "$DST" "$DSTROOTLABEL"; then
+        GRUB=no
+    fi
+fi
+if [[ $GRUB == no ]]; then
+    if [[ $ROOTCOPIED == yes ]]; then
+        log "Warning: root filesystem changed, and skipping grub install on %s, boot will probably fail." "$DST"
+    else
+        log "Warning: Skipping grub install on %s." "$DST"
+    fi
+else
+    log "installing grub on $DST..."
 
-chroot ${GRUB_ROOT} update-grub
-chroot ${GRUB_ROOT} grub-install ${GRUB_DEV}
+    DSTMNT="$AUTOFS_DIR/$DSTROOTLABEL"
+    # mount virtual devices
+    echorun_maybe mount -o bind /sys  "$DSTMNT/sys"
+    echorun_maybe mount -o bind /proc "$DSTMNT/proc"
+    echorun_maybe mount -o bind /dev  "$DSTMNT/dev"
 
-# restart stopped process (db, etc...)
-systemctl start mysql
+    echorun_maybe chroot "$DSTMNT" update-grub
+    echorun_maybe chroot "$DSTMNT" grub-install "$DST"
+fi
+
+exit 0

bash/free-sms-keys.txt

@@ -0,0 +1,2 @@
+bruno:01234567:abcdeABCDE1234
+bodiccea:76543210:xyztXYZT123456

bash/gen-password.sh

@@ -0,0 +1,738 @@
+#!/usr/bin/env bash
+#
+# gen-passwd.sh - a simple password generator.
+#
+# (C) Bruno Raoult ("br"), 2022
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+#%MAN_BEGIN%
+# NAME
+#       gen-passwwd.sh - a simple password generator.
+#
+# SYNOPSIS
+#       gen-passwd.sh [OPTIONS] TYPE [LENGTH]
+#
+# DESCRIPTION
+#       Generate a random TYPE password with length LENGTH.
+#       Available types are :
+#       dice
+#          A list of digits in range [1-6]. Default length is 5. The purpose of
+#          this is only to help choosing a word in a diceware word list.
+#       mac
+#          A "xx-xx-xx-xx-xx-xx" type address, where 'x' are hexadecimal digits
+#          (ranges 0-9 and a-h).
+#          Length is the number of "bytes" (groups of 2 hexadecimal digits), and
+#          defaults to 6. The default ":" delimiter can be changed with "-s"
+#          option.
+#          This is the default option.
+#       passphrase
+#          Generate words from a diceware-like dictionary. Length is the number
+#          of words ans defaults to 6.
+#       pincode
+#          A numeric password. default LENGTH is 4, with no separator.
+#       string
+#          Password will be a string taken from different character ranges.
+#          By default, alphabetic characters and digits. See -x option for
+#          different character sets.
+#
+# OPTIONS
+#       -c, --copy
+#          Copy password to clipboard.
+#
+#       -C, --capitalize
+#          For 'passphrase' and 'mac' type only.
+#          Passphrase: Capitalize words (first letter of each word). Recommended
+#          if separator is set to null-string (--separator=0).
+#          Mac: use capital hexadecimal digits.
+#
+#       -d, --dictionary=FILE
+#          Use FILE as wordlist file. Default is en-5.
+#          FILE will be searched in these directories : root, current directory,
+#          and /usr/local/share/br-tools/gen-password directory.
+#
+#       -g, --gui
+#          Will use a GUI (yad based) to propose the password. This GUI
+#          simply displays the password, allows to copy it to clipboard,
+#          and to re-generate a new password.
+#
+#       -h, --help
+#          Display usage and exit.
+#
+#       -l, --list-dictionaries
+#          Display the list of available dictionaries, with names suitable for
+#          the "-d" option.
+#
+#       -m, --man
+#          Print a man-like help and exit.
+#
+#       -n, --no-similar-chars
+#          For "string" type only, this option removes similar characters which
+#          could be difficult to differenciate: 0-O, 1-l, 8-B, [], ø-Ø, ~--, ...
+#
+#       -s, --separator=CHAR
+#          CHAR is used as separator when TYPE allows it. Use "0" to remove
+#          separators.
+#
+#       -v, --verbose
+#          Print messages on what is being done.
+#
+#       -x, --extended=RANGE
+#          Specify the ranges of string type. Default is "a:1:a1", as lower case
+#          alphabetic characters (a-z) and digits (0-9), with at least one letter
+#          and one digit. RANGE  is a string composed of:
+#          a: lower case alphabetic characters (a-z)
+#          A: upper case alphabetic characters (A-Z)
+#          e: extra European characters (e.g. À, É, é, Ï, ï, Ø, ø...)
+#          1: digits (0-9)
+#          x: extended characters set 1: #$%&@^`~.,:;{[()]}
+#          y: extended characters set 2: "'\/|_-<>*+!?=
+#          k: japanese hiragana: あいうえおかき...
+#          When a RANGED character is followed by a ':' exactly one character of
+#          this range will appear in generated password: If we want two or more
+#          digits, the syntax would be '-x1:1:1'.
+#
+# TODO
+#       Add different languages wordlists.
+#       Replace hiragana with half-width katakana ?
+#       Add usage examples
+#
+# AUTHOR
+#       Bruno Raoult.
+#
+# SEE ALSO
+#       Pages on Diceware/words lists :
+#       EFF: https://www.eff.org/dice
+#       diceware: https://theworld.com/~reinhold/diceware.html
+#
+#%MAN_END%
+
+SCRIPT="$0"                                       # full path to script
+CMDNAME=${0##*/}                                  # script name
+SHELLVERSION=$(( BASH_VERSINFO[0] * 10 + BASH_VERSINFO[1] ))
+
+export LC_CTYPE="C.UTF-8"                         # to handle non ascii chars
+
+# character sets
+declare -A pw_charsets=(
+    [a]="abcdefghijklmnopqrstuvwxyz"
+    [A]="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    [1]="0123456789"
+    [e]="âêîôûáéíóúàèìòùäëïöüãõñçøÂÊÎÔÛÁÉÍÓÚÀÈÌÒÙÄËÏÖÜÃÕÑÇØ¡¿"
+    [x]='#$%&@^`~.,:;{[()]}'
+    [y]=\''"\/|_-<>*+!?='
+    [k]="あいうえおかきくけこさしすせそたちつてとなにぬねのはひふへほまみむめもやゆよらりるれろわをん"
+)
+
+# default type, length, separator
+declare pw_type="mac"
+declare pw_length=6
+declare pw_sep=":"
+declare pw_cap=""
+declare pw_dict=""
+declare pw_copy=""
+declare pw_gui=""
+declare pw_verbose=""
+declare pw_no_similar=""
+declare pw_charset="a:A:1:aA1"
+
+declare -A pw_commands=()
+declare -a pw_command=()
+
+usage() {
+    printf "usage: %s [-s CHAR][-d DICT][-x CHARSET][-Ccgmv] [TYPE] [LENGTH]\n" "$CMDNAME"
+    printf  "Use '%s --man' for more help\n" "$CMDNAME"
+    return 0
+}
+
+man() {
+    sed -n '/^#%MAN_BEGIN%/,/^#%MAN_END%$/{//!s/^#[ ]\{0,1\}//p}' "$SCRIPT" | more
+}
+
+# log() - log messages on stderr
+# parameters:
+# -l, -s: long, or short prefix (default: none). Last one is used.
+# -t: timestamp
+# -n: no newline
+# This function accepts either a string, either a format string followed
+# by arguments :
+#   log -s "%s" "foo"
+#   log -s "foo"
+log() {
+    local timestr="" prefix="" newline=y todo OPTIND
+    [[ -z $pw_verbose ]] && return 0
+    while getopts lsnt todo; do
+        case $todo in
+            l) prefix=$(printf "*%.s" {1..30})
+               ;;
+            s) prefix=$(printf "*%.s" {1..5})
+               ;;
+            n) newline=n
+               ;;
+            t) timestr=$(date "+%F %T%z ")
+               ;;
+            *)
+               ;;
+        esac
+    done
+    shift $((OPTIND - 1))
+    [[ $prefix != "" ]] && printf "%s " "$prefix" >&2
+    [[ $timestr != "" ]] && printf "%s" "$timestr" >&2
+    # shellcheck disable=SC2059
+    printf "$@" >&2
+    [[ $newline = y ]] && printf "\n" >&2
+    return 0
+}
+
+# check_dict() - check for dictionary file
+# $1: the dictionary filename (variable reference).
+#
+# @return: 0 on success, $1 will contain full path to dictionary.
+# @return: 1 if not found
+# @return: 2 if format is wrong
+check_dict() {
+    local -n dict="$1"
+    local tmp_dir tmp_dict tmp_key tmp_dummy
+
+    if [[ -n "$dict" ]]; then
+        for tmp_dir in / ./ /usr/local/share/br-tools/gen-password/; do
+            tmp_dict="$tmp_dir$dict.txt"
+            log -n "checking for %s dictionary... " "$tmp_dict"
+            if [[ -f "$tmp_dict" ]]; then
+                log -n "found, "
+                # shellcheck disable=SC2034
+                read -r tmp_key tmp_dummy < "$tmp_dict"
+                if ! [[ $tmp_key =~ ^[1-6]+$ ]]; then
+                    log "wrong format [%s]" "$tmp_key"
+                    return 2
+                fi
+                log "key length=%d" "${#tmp_key}"
+                dict="$tmp_dict"
+                return 0
+            else
+                log "not found."
+            fi
+        done
+        printf "cannot find '%s' dictionary file\n" "$dict"
+        exit 1
+    fi
+    return 0
+}
+
+# list_dict() - list available dictionaries.
+#
+# @return: 0 on success
+# @return: 1 on error
+list_dict() {
+    local datadir="/usr/local/share/br-tools/gen-password" file fn fn2 key dummy
+    local -a output
+    local -i res=1 cur=0 i
+
+    if [[ -d "$datadir" ]]; then
+        printf -v output[0] "#\tlen\tName"
+        for file in "$datadir"/*.txt; do
+            fn=${file##*/}
+            fn=${fn%.txt}
+            # shellcheck disable=SC2034
+            fn2="$fn"
+            if check_dict fn2; then
+                (( cur++ ))
+                # shellcheck disable=SC2034
+                read -r key dummy < "$file"
+                printf -v output[cur-1] "%d\t%d\t%s" "$cur" "${#key}" "$fn"
+            fi
+        done
+        if ((cur > 0)); then
+            printf "#\tlen\tName\n"
+            for (( i = 0; i < cur; ++i )); do
+                printf "%s\n" "${output[i]}"
+            done
+            return 0
+        fi
+    fi
+    printf "No dictionaries found.\n"
+    return 1
+}
+
+# sanitize() - sanitize string for HTML characters
+# $1: string to cleanup
+#
+# @return: 0, $1 will contain the sanitized string
+sanitize() {
+    local str="$1"
+
+    str=${str//&/&amp;}
+    str=${str//</&lt;}
+    str=${str//>/&gt;}
+    str=${str//'"'/&quot;}
+    log "sanitized string: '%s' -> '%s'" "$1" "$str"
+    printf -- "%str" "$str"
+}
+
+# srandom() - use RANDOM to simulate SRANDOM
+# $1: Reference of variable to hold result
+#
+# Note: RANDOM is 15 bits, SRANDOM is 32 bits.
+#
+# @return: 0, $1 will contain the 32 bits random number
+srandom() {
+    local -n _ret=$1
+
+    (( _ret = RANDOM << 17 | RANDOM << 2 | RANDOM & 3 ))
+}
+
+# rnd() - get a random number integer
+# $1: An integer, the modulo value
+#
+# @return: 0, output a string with the random integer on stdout.
+#
+# This function uses SRANDOM for bash >= 5.1 and srandom() function
+# above for lower versions.
+rnd() {
+    local mod=$1 ret
+
+    if (( SHELLVERSION >= 51 )); then
+        # shellcheck disable=SC2153
+        (( ret = SRANDOM ))
+    else
+        srandom ret
+    fi
+    printf "%d" "$(( ret % mod ))"
+}
+
+# shuffle() - shuffle  a string
+# $1: The string to shuffle
+#
+# The string is shuffled using the Fisher–Yates shuffle method :
+# https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
+#
+# @return: 0,  output the shuffled string to stdout.
+shuffle() {
+    local _str="$1"
+    local _res=""
+    local -i _i _len=${#_str} _cur=0
+
+    for (( _i = _len ; _i > 0; --_i )); do
+        _cur=$(rnd "$_i")
+        _res+=${_str:$_cur:1}
+        _str="${_str:0:_cur}${_str:_cur+1}"
+    done
+    printf "%s" "$_res"
+    return  0
+}
+
+# rnd_hex() - get a random 2-digits hex number
+#
+# @return: 0, output a string with the random integer on stdout.
+rnd_hex() {
+    printf "%02x" "$(rnd 256)"
+}
+
+# rnd_dice() - get a 6 faces 1-6 random number
+#
+# @return: 0, output a string {1..6}
+rnd_dice() {
+    printf "%d" "$(( $(rnd 6) + 1 ))"
+}
+
+# rnd_digit() - get a digit random number
+#
+# @return: 0, output a string {0..9}
+rnd_digit() {
+    printf "%d" "$(( $(rnd 10) ))"
+}
+
+# rnd_word() - get a word from file
+# $1: The dice rolls
+# $2: The word list file ()
+#
+# @return: 0, output a string {0..9}
+rnd_word() {
+    local roll="$1" file="$2" word=""
+
+    word=$(sed -n "s/^${roll}[[:blank:]]\+//p" "$file")
+    printf "%s" "$word"
+}
+
+# rnd_charset() - get a random string from a charset
+# $1: A string with characters to choose from
+# $2: An integer, the length of returned string
+#
+# @return: 0, output a random string from charset $1, with length $2.
+rnd_charset() {
+    local charset="$1" ret=""
+    local -i len=$2 _i
+
+    #log "rnd_charset: %d from  '%s'" "$len" "$charset"
+    for ((_i=0; _i<len; ++_i)); do
+        ret+=${charset:$(rnd ${#charset}):1}
+    done
+
+    #log "rnd_charset: return '%s'" "$ret"
+    printf "%s" "$ret"
+}
+
+# pwd_dice() - get a random dice style string
+# $1: Integer, the number dice runs
+# $2: Separator
+#
+# @return: 0, output dice rolls
+pwd_dice() {
+    local -i i n="${1:-6}"
+    local sep="" _sep="${2}"
+    local str="" _str=""
+
+    for ((i = 0; i < n; ++i)); do
+        printf -v _str  "%s%s" "$sep" "$(rnd_dice)"
+        str+="$_str"
+        sep="$_sep"
+    done
+    printf "%s" "$str"
+    return 0
+}
+pw_commands["dice"]=pwd_dice
+
+# pwd_mac() - get a random MAC-address style string
+# $1: Integer, the number of hex values
+# $2: Separator
+# $3: Capitalize
+#
+# @return: 0, output a random MAC-address style string.
+pwd_pincode() {
+    local -i i n="${1:-6}"
+    local sep="" _sep="${2}" _cap="$3"
+    local str="" _str=""
+
+    for ((i = 0; i < n; ++i)); do
+        printf -v _str  "%s%s" "$sep" "$(rnd_digit)"
+        str+="$_str"
+        sep="$_sep"
+    done
+    [[ -n $_cap ]] && str=${str^^}
+    printf "%s" "$str"
+    return 0
+}
+pw_commands["pincode"]=pwd_pincode
+
+# pwd_mac() - get a random MAC-address style string
+# $1: Integer, the number of hex values (default: 6)
+# $2: Separator (default: "-")
+# $3: Capitalize (default: "")
+#
+# @return: 0, output a random MAC-address style string.
+pwd_mac() {
+    local -i i n="$1"
+    local sep="" _sep="${2}" _cap="$3"
+    local str="" _str=""
+
+    for ((i = 0; i < n; ++i)); do
+        str+="$sep$(rnd_hex)"
+        sep="$_sep"
+    done
+    [[ -n $_cap ]] && str=${str^^}
+    printf "%s" "$str"
+    return 0
+}
+pw_commands["mac"]=pwd_mac
+
+# pwd_passphrase() - get a list of words from a diceware-style file
+# $1: Integer, the number of words
+# $2: Separator
+# $3: Capitalize
+# $4: diceware file
+#
+# @return: 0, output a random MAC-address style string.
+pwd_passphrase() {
+    local -i i n="$1" _digits=0
+    local sep="" _sep="${2}" _cap="$3" _file="$4"
+    local str="" _str="" _key="" _dummy=""
+
+    # get the number of digits from 1st file line
+    read -r _key _dummy < "$_file"
+    _digits=${#_key}
+    log "passphrase setup: key 1=%s digits=%d" "$_key" "$_digits"
+
+    for ((i = 0; i < n; ++i)); do
+        _key=$(pwd_dice "$_digits" "")
+        _str=$(rnd_word "$_key" "$_file")
+        [[ -n $_cap ]] && _str=${_str^}
+        log "passphrase: key=%s str=%s" "$_key" "$_str"
+        str+="$sep$_str"
+        sep="$_sep"
+    done
+    printf "%s" "$str"
+    return 0
+}
+pw_commands["passphrase"]=pwd_passphrase
+
+# pwd_string() - generate a string from a charset
+# $1: Integer, the string length
+# $5: The charset definition (e.g. "a:1:")
+#
+# @return: 0, output a random string from $5 charset.
+pwd_string() {
+    local -i i n="$1"
+    local _charset="${5}" _allchars=""
+    local str="" _c="" _char=""
+
+    log "string setup: len=%d charset=[%s]" "$n" "$_charset"
+    # finds out mandatory characters and build final charset
+    log -n "mandatory chars:"
+    for (( i = 0; i < ${#_charset}; ++i )); do
+        _c="${_charset:i:1}"
+        if [[ ${_charset:i+1:1} == ":" ]]; then
+            _char=$(rnd_charset "${pw_charsets[$_c]}" 1)
+            log -n " [%s]" "$_char"
+            str+="$_char"
+            (( i++ ))
+        else
+            _allchars+=${pw_charsets[$_c]}
+        fi
+    done
+    log ""
+    if (( ${#str} < n && ${#_allchars} == 0 )); then
+        printf "Fatal: No charset to choose from ! Please check  '-x' option."
+        exit 1
+    fi
+
+    log -n "generating %d remaining chars:" "$((n-${#str}))"
+    for ((i = ${#str}; i < n; ++i)); do
+        _char=$(rnd_charset "$_allchars" 1)
+        log -n " [%s]" "$_char"
+        str+="$_char"
+    done
+    log ""
+    log "string before shuffle : %s" "$str"
+    str="$(shuffle "$str")"
+    log "string after shuffle : %s" "$str"
+    # cut string if too long (may happen if too many mandatory chars)
+    (( ${#str} > n)) && log  "truncating '%s' to '%s'" "$str" "${str:0:n}"
+    printf "%s" "${str:0:n}"
+    return 0
+}
+pw_commands["string"]=pwd_string
+
+# print command() - print a pwd_command parameters
+# $1: reference of pwd_command array
+#
+# @return: 0
+print_command() {
+    local -n arr="$1"
+    local -a label=("function" "length" "sep" "cap" "dict" "charset")
+    local -i i
+    for i in "${!arr[@]}"; do
+        log -s "%s=[%s]" "${label[$i]}" "${arr[$i]}"
+    done
+    return 0
+}
+
+# gui_passwd() - GUI for passwords
+# $1: reference pwd_command array
+#
+# @return: 0
+gui_passwd() {
+    local -a _command=("$@")
+    local passwd="" res=0 sane=""
+
+    while
+        passwd=$("${_command[@]}")
+        sane=$(sanitize "$passwd")
+        yad --title="Password Generator" --text-align=center --text="$sane" \
+            --borders=20 --button=gtk-copy:0 --button=gtk-refresh:1 \
+            --button=gtk-ok:252 --window-icon=dialog-password
+        res=$?
+        log "res=%d\n" "$res"
+        if (( res == 0 )); then
+            printf "%s" "$passwd" | xsel -bi
+        fi
+        ((res != 252))
+    do true;  done
+    return $res
+}
+
+parse_opts() {
+    # short and long options
+    local sopts="cCd:ghlmns:vx:"
+    local lopts="copy,capitalize,dictionary:,gui,help,list-dictionaries,man,no-similar-chars,separator:,verbose,extended:"
+    # set by options
+    local tmp="" tmp_length="" tmp_sep="" tmp_cap="" tmp_dict="" tmp_dir=""
+    local tmp_charset=""
+    local c2="" c3=""
+    local  -i  i
+
+    if ! tmp=$(getopt -o "$sopts" -l "$lopts" -n "$CMD" -- "$@"); then
+        log "Use '$CMD --help' or '$CMD --man' for help."
+        exit 1
+    fi
+
+    eval set -- "$tmp"
+
+    while true; do
+        case "$1" in
+            '-c'|'--copy')
+                pw_copy=y
+                ;;
+            '-C'|'--capitalize')
+                tmp_cap=y
+                ;;
+            '-d'|'--dictionary')
+                tmp_dict="$2"
+                shift
+                ;;
+            '-g'|'--gui')
+                if ! type -P "yad" > /dev/null; then
+                    printf "%s: Please install 'yad' package tu use 'g' option.\n" \
+                           "$CMDNAME"
+                fi
+                pw_gui="y"
+                ;;
+            '-h'|'--help')
+                usage
+                exit 0
+                ;;
+            '-l'|'--list-dictionaries')
+                list_dict
+                exit 0
+                ;;
+            '-m'|'--man')
+                man
+                exit 0
+                ;;
+            '-n'|'no-similar-chars')
+                pw_no_similar=y
+                ;;
+            '-s'|'--separator')
+                tmp_sep="$2"
+                shift
+                ;;
+            '-v'|'--verbose')
+                pw_verbose=y
+                ;;
+            '-x'|'--extended')
+                for (( i = 0; i < ${#2}; ++i)); do
+                    c2="${2:i:1}"
+                    case "$c2" in
+                        a|A|1|x|y|k|e)
+                            tmp_charset+="$c2"
+                            c3="${2:i+1:1}"
+                            if [[ "$c3" == ":" ]]; then
+                                tmp_charset+=":"
+                                (( i++ ))
+                            fi
+                            ;;
+
+                        *) printf "unknown character set '%s\n" "${2:$i:1}"
+                           usage
+                           exit 1
+                    esac
+                done
+                shift
+                ;;
+            '--')
+                shift
+                break
+                ;;
+            *)
+                usage
+                log 'Internal error!'
+                exit 1
+                ;;
+        esac
+        shift
+    done
+
+    # parse remaining arguments
+    if (($# > 0)); then                               # type
+        type=$1
+        case "$type" in
+            dice)
+                pw_type="dice"
+                tmp_length=5
+                [[ -z $tmp_sep ]] && tmp_sep=" "
+                ;;
+            mac)
+                pw_type="mac"
+                tmp_length=6
+                [[ -z $tmp_sep ]] && tmp_sep=":"
+                ;;
+            pincode)
+                pw_type="pincode"
+                tmp_length=4
+                [[ -z $tmp_sep ]] && tmp_sep="0"
+                ;;
+            passphrase)
+                pw_type="passphrase"
+                tmp_length=6
+                [[ -z $tmp_dict ]] && tmp_dict="en-5"
+                [[ -z $tmp_sep ]] && tmp_sep=" "
+                [[ -z $tmp_cap ]] && tmp_cap=""
+                ;;
+            string)
+                pw_type="string"
+                tmp_length=10
+                if [[ -n $pw_no_similar ]]; then
+                    pw_charsets[A]="ABCDEFGHIJKLMNPQRSTUVWXYZ"
+                    pw_charsets[a]="abcdefghijkmnopqrstuvwxyz"
+                    pw_charsets[1]="23456789"
+                    pw_charsets[e]="âêîôûáéíóúàèìòùñçÂÊÎÔÛÁÉÍÓÚÀÈÌÒÙÇ¡¿"
+                    pw_charsets[x]='#$%&@^`.,:;{()}'
+                    pw_charsets[y]='\/|_<>*+!?='
+                fi
+                if [[ -n $tmp_charset ]]; then
+                    pw_charset="$tmp_charset"
+                fi
+                ;;
+            *)
+                printf "%s: Unknown '%s' password type.\n" "$CMDNAME" "$type"
+                usage
+                exit 1
+        esac
+        shift
+    fi
+    if (($# > 0)); then                               # length
+        if ! [[ $1 =~ ^[0-9]+$ ]]; then
+            printf "%s: Bad '%s' length.\n" "$CMDNAME" "$1"
+            usage
+            exit 1
+        fi
+        tmp_length="$1"
+        shift
+    fi
+    [[ -n $tmp_length ]] && pw_length=$tmp_length
+    if ! (( pw_length )); then
+        printf "%s: Bad '%d' length.\n" "$CMDNAME" "$tmp_length"
+        usage
+        exit 1
+    fi
+    [[ -n $tmp_sep   ]] && pw_sep=$tmp_sep
+    [[ $pw_sep = "0" ]] && pw_sep=""
+    [[ -n $tmp_cap   ]] && pw_cap=$tmp_cap
+    [[ -n $tmp_dict  ]] && pw_dict=$tmp_dict
+
+    # look for dictionary file
+    check_dict pw_dict || exit 1
+}
+
+parse_opts "$@"
+
+pw_command=("${pw_commands[$pw_type]}" "$pw_length" "$pw_sep" "$pw_cap" "$pw_dict"
+           "$pw_charset")
+
+print_command pw_command
+
+if [[ -z $pw_gui ]]; then
+    passwd=$("${pw_command[@]}")
+    if [[ -n $pw_copy ]]; then
+        printf "%s" "$passwd" | xsel -bi
+    fi
+    printf "%s\n" "$passwd"
+else
+    gui_passwd "${pw_command[@]}"
+fi
+
+exit 0

bash/share/gen-password/README.md

@@ -0,0 +1,18 @@
+### Dictionaries for gen-password.sh
+
+#### English
+
+Lists taken from :
+[EFF word list](https://www.eff.org/fr/deeplinks/2016/07/new-wordlists-random-passphrases). I am unsure about licensing.
+
+* [Large list](eff_large_wordlist.txt): To use with 5 dices.
+* [Short list 1](eff_short_wordlist_1.txt): To use with 4 dices.
+* [Short list 2](eff_short_wordlist_2_0.txt): 4 dices, with some improvements.
+
+#### Français
+
+Listes prises sur [github.com/mbelivo/diceware-wordlists-fr](https://github.com/mbelivo/diceware-wordlists-fr). La licence est CC BY-NC-SA 3.0.
+
+* [Liste Longue](wordlist_fr_5d.txt): Pour 5 dés.
+* [Liste Courte 1](wordlist_fr_4d.txt): Pour 4 dés.
+* [Liste Courte 2](wordlist_fr_4d_2.txt): Pour 4 dés, avec quelques améliorations.

bash/share/gen-password/en-4-2.txt

@@ -0,0 +1 @@
+eff_short_wordlist_2_0.txt

bash/share/gen-password/en-4.txt

@@ -0,0 +1 @@
+eff_short_wordlist_1.txt

bash/share/gen-password/en-5.txt

@@ -0,0 +1 @@
+eff_large_wordlist.txt

bash/share/gen-password/fr-4-2.txt

@@ -0,0 +1 @@
+wordlist_fr_4d_2.txt

bash/share/gen-password/fr-4.txt

@@ -0,0 +1 @@
+wordlist_fr_4d.txt

bash/share/gen-password/fr-5.txt

@@ -0,0 +1 @@
+wordlist_fr_5d.txt

bash/share/sync/sync-conf-example.sh

@@ -0,0 +1,114 @@
+#!/usr/bin/env bash
+#
+# sync-conf-example.sh - a "sync.sh" configuration file example.
+#
+# (C) Bruno Raoult ("br"), 2007-2022
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+# USAGE:
+#    sync.sh -rfu /path/to/sync-conf-example.sh
+
+# below, default values are just below the lines starting with '######'.
+# The only mandatory ones are SOURCEDIR, SERVER, and DESTDIR.
+
+###### source directory full path, destination server and path.
+###### SERVER could be user@host, or "local" if local machine
+# SOURCEDIR=""
+# SERVER=""
+# DESTDIR=""
+export SOURCEDIR=/example-srcdir
+export SERVER=root@backuphost
+export DESTDIR=/mnt/nas1/example-destdir
+
+###### backups mount point on local machine.
+###### it is used by sync-view.sh only.
+export BACKUPDIR=/mnt/backup-example-srcdir
+
+###### backups to keep
+# NYEARS=3
+# NMONTHS=12
+# NWEEKS=6
+# NDAYS=10
+
+###### other rsync options. It must be an array.
+# RSYNCOPTS=()
+FILTERNAME=".rsync-filter-system"
+FILTER=--filter="dir-merge ${FILTERNAME}"
+RSYNCOPTS+=("$FILTER")
+
+###### functions run immediately before and after the rsync. Can be used
+###### to create database dumps, etc...
+###### Warning: avoid using "cd", or be sure to come back to current dir
+###### before returning from functions
+# beforesync() { log "calling default beforesync..."; }
+# aftersync()  { log "calling default aftersync...";  }
+
+# example below will create a mysql/mariadb dump. At same time we create
+# a FILTERNAME file in database data directory to exclude databases directories
+# themselves.
+beforesync() {
+    local -a databases
+    local datadir
+
+    # log is a sync.sh function.
+    log -s -t "calling user beforesync: mysql databases dumps..."
+
+    if ! datadir="$(mysql -sN -u root -e 'select @@datadir')"; then
+        log -s "cannot get maria databases directory"
+        exit 1
+    fi
+
+    # dump users and permissions
+    log -n "dumping users and permissions... "
+    mysqldump --user=root --system=users > "$datadir/mariadb_users.sql"
+    log -n "compressing... "
+    gzip -f "$datadir/mariadb_users.sql"
+    log "done."
+
+    rm -f "$datadir/$FILTERNAME"
+    # shellcheck disable=2207
+    if ! databases=( $(mysql -sN -u root -e "SHOW DATABASES;") ); then
+        log -s "cannot get maria databases list"
+        exit 1
+    fi
+
+    for db in "${databases[@]}"; do
+        # do not backup database contents itself
+        printf -- "- /%s/*\n" "$db" >> "$datadir/$FILTERNAME"
+
+        log -n "$db... "
+        case "$db" in
+            information_schema|performance_schema)
+                log "skipped."
+                ;;
+            *)
+                log -n "dumping to $datadir$db.sql... "
+                if ! mysqldump --user=root --single-transaction --routines \
+                     "$db" > "$datadir/$db.sql"; then
+                    log -s "mysqldump error"
+                    exit 1
+                fi
+                log -n "compressing... "
+                gzip -f "$datadir/$db.sql"
+                log "done."
+        esac
+    done
+    # log "filtername contains:"
+    # cat ${datadir}/${FILTERNAME}
+}
+
+aftersync() {
+    # we may remove the dump here...
+    log -s -t "calling user aftersync"
+}
+
+# For Emacs, shell-script-mode:
+# Local Variables:
+# mode: shell-script
+# End:

bash/sms-free.sh

@@ -0,0 +1,324 @@
+#!/usr/bin/env bash
+#
+# sms-free.sh - send SMS to Free Mobile.
+#
+# (C) Bruno Raoult ("br"), 2022
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+#%MAN_BEGIN%
+# NAME
+#       sms-free.sh - Send SMS to Free Mobile account.
+#
+# SYNOPSIS
+#       sms-free.sh [OPTIONS] [-k KEYFILE] USER [MESSAGE]
+#       sms-free.sh [OPTIONS] [-l LOGIN:PASSWORD] [MESSAGE]
+#
+# DESCRIPTION
+#       Send a SMS to a Free Mobile (french mobile operator). This script will
+#       only work for phones numbers for which you have the "SMS key" (see FREE
+#       MOBILE SMS SETUP below). Therefore yourself, close relatives, and other
+#       people who trust you).
+#       MESSAGE is the text to be sent. If missing, it will be read from standard
+#       input.
+#
+# OPTIONS
+#       -d, --dry-run
+#          Will not send the SMS.
+#
+#       -h, --help
+#          Display usage and exit.
+#
+#       -l, --login=ACCOUNT:SMSKEY
+#          Do not use a KEYFILE, and provide directly the Free Mobile ACCOUNT
+#          and SMSKEY.
+#
+#       -k, --keyfile=KEYFILE
+#          Use KEYFILE instead of default ~/data/private/free-sms-keys.txt.
+#
+#       -m, --man
+#          Print a man-like help and exit.
+#
+#       -v, --verbose
+#          Print messages on what is being done.
+#
+# FREE MOBILE SMS SETUP
+#       You should first connect on https://mobile.free.fr/account/, and
+#       activate the option "Mes options / Notifications par SMS". You will be
+#       given a key.
+#
+# KEY FILE SYNTAX
+#       The key file contains lines of the form:
+#            id:login:password
+#       id
+#          A mnemonic for the user (firstname, etc...), it should be unique.
+#       login
+#          A valid Free Mobile account number (usually 8 digits).
+#       key
+#          The SMS key associated with the Free Mobile login (usually a 14
+#          alphanumeric string).
+#
+#       Example:
+#       bruno:01234567:abcdeABCDE1234
+#       bodiccea:76543210:xyztXYZT123456
+#
+# AUTHOR
+#       Bruno Raoult.
+#%MAN_END%
+#
+# PERSONAL NOTES/TODO
+#       In example above, "%20" can be replaced by "+"
+#          See: https://www.w3.org/TR/html4/interact/forms.html#h-17.13.4.1
+#       utf8 characters look supported (tested on French accentuated characters,
+#          Japanese kana and kanji, and Chinese)
+#
+# FREE MOBILE DOCUMENTATION
+#
+#        L'envoi du SMS se fait en appelant le lien suivant :
+#
+#        https://smsapi.free-mobile.fr/sendmsg
+#        avec les paramètres suivants :
+#
+#            user : votre login
+#            pass : votre clé d'identification générée automatiquement par notre
+#                   service
+#            msg  : le contenu du SMS encodé sous forme d'url (Percent-encoding)
+#
+#        Exemple : Envoyer le message "Hello World !" sur votre mobile :
+#
+#        https://smsapi.free-mobile.fr/sendmsg?user=12345678&pass=abcABC12345678&msg=Hello%20World%20!
+#
+#        Vous pouvez également, si vous le préférez, envoyer les paramètres en POST.
+#        Dans ce cas, le contenu du message n'a pas besoin d'être encodé.
+#        Le code de retour HTTP indique le succès ou non de l'opération :
+#
+#            200 : Le SMS a été envoyé sur votre mobile.
+#            400 : Un des paramètres obligatoires est manquant.
+#            402 : Trop de SMS ont été envoyés en trop peu de temps.
+#            403 : Le service n'est pas activé sur l'espace abonné, ou login / clé
+#                  incorrect.
+#            500 : Erreur côté serveur. Veuillez réessayer ultérieurement.
+
+#set -x
+script="$0"                                       # full path to script
+cmdname=${0##*/}                                  # script name
+export LC_CTYPE="C.UTF-8"                         # to handle non ascii chars
+
+declare sms_keyfile=~/data/private/free-sms-keys.txt
+declare sms_verbose=""
+declare sms_credentials=""
+declare sms_dryrun=""
+declare sms_message=""
+declare sms_url="https://smsapi.free-mobile.fr/sendmsg"
+declare -A sms_status=(
+    [-]="Unknown error"
+    [200]="OK"
+    [400]="Missing parameter"
+    [402]="Too many SMS sent in short time"
+    [403]="Service non activated or incorrect credentials"
+    [500]="Server error"
+)
+
+usage() {
+    printf "usage: %s [-hmv] [-k KEYFILE] USER [MESSAGE]\n" "$cmdname"
+    printf "       %s [-hmv] [-l LOGIN:PASSWORD] [MESSAGE]\n" "$cmdname"
+    printf  "Use '%s --man' for more help\n" "$cmdname"
+    return 0
+}
+
+man() {
+    sed -n '/^#%MAN_BEGIN%/,/^#%MAN_END%$/{//!s/^#[ ]\{0,1\}//p}' "$script" | more
+}
+
+# log() - log messages on stderr
+# parameters:
+# -l, -s: long, or short prefix (default: none). Last one is used.
+# -t: timestamp
+# -n: no newline
+# This function accepts either a string, either a format string followed
+# by arguments :
+#   log -s "%s" "foo"
+#   log -s "foo"
+log() {
+    local timestr="" prefix="" newline=y todo OPTIND
+    [[ -z $sms_verbose ]] && return 0
+    while getopts lsnt todo; do
+        case $todo in
+            l) prefix=$(printf "*%.s" {1..30})
+               ;;
+            s) prefix=$(printf "*%.s" {1..5})
+               ;;
+            n) newline=n
+               ;;
+            t) timestr=$(date "+%F %T%z ")
+               ;;
+            *)
+               ;;
+        esac
+    done
+    shift $((OPTIND - 1))
+    [[ $prefix != "" ]] && printf "%s " "$prefix" >&2
+    [[ $timestr != "" ]] && printf "%s" "$timestr" >&2
+    # shellcheck disable=SC2059
+    printf "$@" >&2
+    [[ $newline = y ]] && printf "\n" >&2
+    return 0
+}
+
+# echorun() - logs and run (maybe) a command.
+# $1: reference of variable which will get the output of command
+# $2..$n: command to log and run
+echorun() {
+    local -n _out="$1"
+    shift
+    [[ -n $sms_dryrun ]] && log -n "dry-run: "
+    log "%s" "$*"
+    [[ -z $sms_dryrun ]] && _out=$("$@")
+    return $?
+}
+
+# get_credentials() - get credentials from keyfile
+# $1: reference of variable which will contain credentials
+# $2: keyfile
+# $3: user to find
+#
+# @return: 0 on success
+# @return: 1 on file not present or not readable
+# @return: 2 if user not found
+get_credentials() {
+    local -n _cred=$1
+    local _keyfile="$2" _user="$3" _name=""
+
+    log "get_credentials: ref=%s user=%s keyfile=%s" "$!_cred" "$_user" "$_keyfile"
+    if [[ ! -r "$_keyfile" ]]; then
+        printf "%s: cannot read keyfile %s\n" "$cmdname" "$_keyfile"
+        return 2
+    fi
+    while IFS=: read -r _name _cred; do
+        log -n "key: name=[%s] creds=[%s]... " "$_name" "$_cred"
+        [[ $_name = "$_user" ]] && log "match." && return 0
+        log "skipping."
+    done  < "$_keyfile"
+    printf "%s: cannot find credentials for user '%s'\n" "$cmdname" "$_user"
+    return 2
+}
+
+parse_opts() {
+    # short and long options
+    local sopts="dhk:l:mv"
+    local lopts="dry-run,help,keyfile:,login:,man,verbose"
+
+    if ! tmp=$(getopt -o "$sopts" -l "$lopts" -n "$cmdname" -- "$@"); then
+        log "Use '%s --help' or '%s --man' for help." "$cmdname" "$cmdname"
+        exit 1
+    fi
+
+    eval set -- "$tmp"
+
+    while true; do
+        case "$1" in
+            '-d'|'--dry-run')
+                sms_dryrun=y
+                ;;
+            '-h'|'--help')
+                usage
+                exit 0
+                ;;
+            '-k'|'--keyfile')
+                sms_keyfile="$2"
+                shift
+                ;;
+            '-l'|'--login')
+                sms_credentials="$2"
+                log "sms_creds=%s" "$sms_credentials"
+                shift
+                ;;
+            '-m'|'--man')
+                man
+                exit 0
+                ;;
+            '-v'|'--verbose')
+                sms_verbose=y
+                ;;
+            '--')
+                shift
+                break
+                ;;
+            *)
+                usage
+                log 'Internal error!'
+                exit 1
+                ;;
+        esac
+        shift
+    done
+
+    # parse remaining arguments
+    case "$#" in
+        0)
+            # no user, no message: we need sms_credentials
+            if [[ -z $sms_credentials ]]; then
+                printf "%s: Missing credentials.\n" "$cmdname"
+                exit 1
+            fi
+            ;;
+        1|2)
+            # get credentials from KEYFILE
+            if [[ -z $sms_credentials ]]; then
+                get_credentials sms_credentials "$sms_keyfile" "$1" || exit 1
+                shift
+            else
+                # cannot have user and sms_credentials
+                (( $# == 2 )) && usage && exit 1
+            fi
+            if [[ $# == 1 ]]; then
+                sms_message="$1"
+            else
+                readarray sms_message
+                printf -v sms_message "%s" "${sms_message[@]}"
+                sms_message=${sms_message%$'\n'}          # remove trailing '\n'
+            fi
+            ;;
+        *)
+            usage
+            ;;
+    esac
+
+    log "credentials=%s" "$sms_credentials"
+    log "message=[%s]" "$sms_message"
+}
+
+# send-sms() - send SMS (GET method)
+send_sms() {
+    local _login=${sms_credentials%:*} _pass=${sms_credentials#*:} _res="" _str=""
+
+    log "send_sms(): login=%s pass=%s" "$_login" "$_pass"
+    echorun _res curl --silent --get --write-out '%{http_code}' \
+            --data "user=$_login" \
+            --data "pass=$_pass" \
+            --data-urlencode "msg=$sms_message" \
+            "$sms_url"
+    [[ -n $sms_dryrun ]] && _res=200
+    _str="${sms_status[$_res]:-${sms_status[-]}}"
+    log "send_sms(): curl status=%s (%s)" "$_res" "$_str"
+    if [[ $_res != 200 ]]; then
+        printf "%s: %s\n" "$cmdname" "$_str"
+    fi
+}
+
+parse_opts "$@"
+send_sms
+exit 0
+
+# Indent style for emacs
+# Local Variables:
+# sh-basic-offset: 4
+# sh-indentation: 4
+# indent-tabs-mode: nil
+# comment-column: 32
+# End:

bash/sync-conf-example.sh

@@ -1,84 +0,0 @@
-#!/bin/bash
-#
-# sync-conf-example.sh - a "sync.sh" configuration file example.
-#
-# (C) Bruno Raoult ("br"), 2007-2021
-# Licensed under the Mozilla Public License (MPL) version 2.0.
-# Some rights reserved. See COPYING.
-#
-# You should have received a copy of the Mozilla Public License along with this
-# program.  If not, see <https://www.mozilla.org/en-US/MPL>
-#
-# SPDX-License-Identifier: MPL-2.0 <https://spdx.org/licenses/MPL-2.0.html>
-#
-# USAGE:
-#    sync.sh -rfu /path/to/sync-conf-example.sh
-
-# full source path
-SOURCEDIR=/example-srcdir
-# server name. Could also be user@hostname
-SERVER=backuphost
-# full destination path on target machine (or relative to home directory)
-DESTDIR=/mnt/array3+4/example-destdir
-
-# backups to keep
-NYEARS=2
-NMONTHS=12
-NWEEKS=4
-NDAYS=7
-
-# FILTER can be used to filter directories to include/exclude. See rsync(1) for
-# details.
-FILTER=--filter="dir-merge .rsync-filter-br"
-
-# other rsync options
-RSYNCOPTS=""
-
-# functions run just before and after the rsync. Could be useful to create
-# database dumps, etc...
-# Warning: avoid using "cd", or be sure to come back to current dir
-# before returning from functions
-
-# example below will create a dump
-function beforesync() {
-    # next line may be removed if you do something. bash does not like empty
-    # functions
-    :
-
-    # log is a sync.sh function.
-    log -s -t "calling user beforesync: mysql databases dumps..."
-
-    datadir=$(mysql -sN -u root -e 'select @@datadir')
-    # log "mysql datadir=${datadir}"
-    rm -f "$datadir/$FILTERNAME"
-    databases=($(mysql -sN -u root -e "SHOW DATABASES;"))
-
-    for db in "${databases[@]}"
-    do
-        # exclude database directory itself
-		echo "- /${db}/*" >> "$datadir/$FILTERNAME"
-
-        log -n "${db}... "
-        case "$db" in
-            information_schema|performance_schema)
-                log "skipped."
-                ;;
-            *)
-                log -n "dumping to ${datadir}${db}.sql... "
-                mysqldump --user=root --routines "$db" > "$datadir/$db.sql"
-                # log -n "compressing... "
-                gzip "$datadir/$db.sql"
-                log "done."
-        esac
-    done
-    # log "filtername contains:"
-    # cat ${datadir}/${FILTERNAME}
-}
-
-function aftersync() {
-    # next line may be removed if you do something. bash does not like empty
-    # functions
-    :
-    # we may remove the dump here...
-    log -s -t "calling user aftersync"
-}

bash/sync-view.sh

@@ -0,0 +1,391 @@
+#!/usr/bin/env bash
+#
+# sync-view.sh - view file versions in a sync.sh backup directory.
+#
+# (C) Bruno Raoult ("br"), 2007-2022
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+#%MAN_BEGIN%
+# NAME
+#       sync-view.sh - list file versions from rsync.sh backups.
+#
+# SYNOPSIS
+#       sync-view.sh [OPTIONS] TARGET
+#
+# DESCRIPTION
+#       List TARGET versions from a sync.sh backup directory.
+#
+# OPTIONS
+#       -1, --unique
+#          Skip duplicate files. This option do not apply if TARGET is a
+#          directory.
+#
+#       -a, --absolute-target
+#          Do not try to resolve TARGET path. By default, the script will try to
+#          guess TARGET absolute path. This is not possible if current system is
+#          different from the one from which the backup was made, or if some
+#          path component are missing or were changed.
+#          If this option is used, TARGET must be an absolute path as it was on
+#          backuped machine.
+#
+#       -b, --backupdir=DIR
+#          DIR is the local path where the backups can be found. It can be a
+#          network mount, or the destination directory if the backup was local.
+#          This option is mandatory.
+#
+#       -c, --config
+#          A sync.sh configuration file where the script could find variables
+#          SOURCEDIR (option '-r') and BACKUPDIR (option '-b').
+#          If this option is missing, the script will try to find a .syncrc file
+#          in DIR/daily-01 directory, where DIR is the local path of backups
+#          (option -b).
+#
+#       -d, --destdir
+#          Directory which will hold links to actual files. It will be created
+#          if non-existant. If this option is missing, a temporary directory will
+#          be created in /tmp.
+#
+#       -h, --help
+#          Display short help and exit.
+#
+#       -m, --man
+#          Display a "man-like" description and exit.
+#
+#       -r, --root=DIR
+#          DIR is the path of the backup source. If '-c' option is used, the
+#          variable SOURCEDIR will be used. By default '/'.
+#
+#       -v, --verbose
+#          Print messages on what is being done.
+#
+#       -x, --exclude=REGEX
+#          Filenames matching REGEX (with relative path to backup directory,
+#          as specified with '-b' option) will be excluded. This option can be
+#          useful
+#
+# EXAMPLES
+#       The next command will list all .bashrc versions for current user, from
+#       backups in /mnt/backup. yearly and monthly-03 to monthly-09 are
+#       excluded. Source directory (-r) of backups are taken from sync.sh
+#       configuration file named s.conf. A temporary directory will be created
+#       in /mnt to handle links to actual files.
+#       $ sync-view.sh -c s.conf -b /mnt/backup -x "^(yearly|monthly-0[3-9]).*$" ~/.bashrc
+#
+#       The simplest invocation: the versions of users' .bashrc will be retrieved
+#       in backups from /mnt/backup. A /mnt/backup/daily-01/.syncrc must exist.
+#       $ sync-view.sh -b /mnt/backup ~/.bashrc
+#
+#       Links to user's .bashrc backups will be put in /tmp/test. Files are in
+#       /mnt/backup, which contains backups of /export directory. The /tmp/test
+#       directory will be created if necessary.
+#       $ sync-view.sh -r /export -b /mnt/backup -d /tmp/test ~/.bashrc
+#
+# AUTHOR
+#       Bruno Raoult.
+#
+#%MAN_END%
+
+# internal variables, cannot (and *should not*) be changed unless you
+# understand exactly what you do.
+SCRIPT="$0"                                       # full path to script
+CMDNAME=${0##*/}                                  # script name
+HOSTNAME="$(hostname)"
+
+ROOTDIR="/"                                       # root of backup source
+BACKUPDIR=""                                      # the local view of backup dirs
+TARGETDIR=""                                      # temp dir to hold links
+
+TARGET=""                                         # the file/dir to find
+RESOLVETARGET=y                                   # resolve TARGET
+UNIQUE=""                                         # omit duplicate files
+EXCLUDE=""                                        # regex for files to exclude
+VERBOSE=""                                        # -v option
+declare -A INODES                                 # inodes table (for -1 option)
+
+# error management
+set -o errexit
+#set -o xtrace
+
+usage() {
+    printf "usage: %s [-b BACKUPDIR][-c CONF][-d DSTDIR][-r ROOTDIR][-x EXCLUDE][-1ahmv] file\n" "$CMDNAME"
+    return 0
+}
+
+man() {
+    sed -n '/^#%MAN_BEGIN%/,/^#%MAN_END%$/{//!s/^#[ ]\{0,1\}//p}' "$SCRIPT" | more
+}
+
+# log function
+# parameters:
+# -l, -s: long, or short prefix (default: none). Last one is used.
+# -t: timestamp
+# -n: no newline
+# This function accepts either a string, either a format string followed
+# by arguments :
+#   log -s "%s" "foo"
+#   log -s "foo"
+log() {
+    local timestr="" prefix="" newline=y todo OPTIND
+    [[ -z $VERBOSE ]] && return 0
+    while getopts lsnt todo; do
+        case $todo in
+            l) prefix=$(printf "*%.s" {1..30})
+               ;;
+            s) prefix=$(printf "*%.s" {1..5})
+               ;;
+            n) newline=n
+               ;;
+            t) timestr=$(date "+%F %T%z ")
+               ;;
+            *)
+               ;;
+        esac
+    done
+    shift $((OPTIND - 1))
+    [[ $prefix != "" ]] && printf "%s " "$prefix"
+    [[ $timestr != "" ]] && printf "%s" "$timestr"
+    # shellcheck disable=SC2059
+    printf "$@"
+    [[ $newline = y ]] && printf "\n"
+    return 0
+}
+
+# filetype() - get file type
+#
+# $1: the file to check
+#
+# @return: 0, output a string with file type on stdout.
+filetype() {
+    local file="$1" type="unknown"
+    if [[ ! -e "$file" ]]; then
+        type="missing"
+    elif [[ -h "$file" ]]; then
+        type="symlink"
+    elif [[ -f "$file" ]]; then
+        type="file"
+    elif [[ -d "$file" ]]; then
+        type="directory"
+    elif [[ -p "$file" ]]; then
+        type="fifo"
+    elif [[ -b "$file" || -c "$file" ]]; then
+        type="device"
+    fi
+    printf "%s" "$type"
+    return 0
+}
+
+# command-line parsing / configuration file read.
+parse_opts() {
+    # short and long options
+    local sopts="1ab:c:d:hmr:vx:"
+    local lopts="unique,absolute-target,backupdir:,config:,destdir:,help,man,root:,verbose,exclude:"
+    local tmp tmp_destdir="" tmp_destdir="" tmp_rootdir="" tmp_config=""
+
+    if ! tmp=$(getopt -o "$sopts" -l "$lopts" -n "$CMD" -- "$@"); then
+        log "Use '$CMD --help' or '$CMD --man' for help."
+        exit 1
+    fi
+
+    eval set -- "$tmp"
+
+    while true; do
+        case "$1" in
+            -1|--unique)
+                UNIQUE=yes
+                ;;
+            '-a'|'--absolute-target')
+                RESOLVETARGET=""
+                ;;
+            '-b'|'--backupdir')
+                tmp_backupdir="$2"
+                shift
+                ;;
+            '-c'|'--config')
+                # The configuration file contains the variable SOURCEDIR, which will allow
+                # to find the relative path of TARGET in backup tree.
+                # it may also contain BACKUPDIR variable, which the local root of backup
+                # tree.
+                tmp_config="$2"
+                shift
+                ;;
+            '-d'|'--destdir')
+                tmp_destdir="$2"
+                shift
+                ;;
+            '-h'|'--help')
+                usage
+                exit 0
+                ;;
+            '-m'|'--man')
+                man
+                exit 0
+                ;;
+            '-r'|'--rootdir')
+                tmp_rootdir="$2"
+                shift
+                ;;
+            '-v'|'--verbose')
+                VERBOSE=yes
+                ;;
+            '-x'|'--exclude')
+                EXCLUDE="$2"
+                shift
+                ;;
+            '--')
+                shift
+                break
+                ;;
+            *)
+                usage
+                log 'Internal error!'
+                exit 1
+                ;;
+        esac
+        shift
+    done
+    # Now check remaining argument (searched file).
+    if (( $# != 1 )); then
+        usage
+        exit 1
+    fi
+    TARGET="$1"
+    [[ -z $RESOLVETARGET ]] || TARGET="$(realpath -L "$TARGET")"
+
+    # if $config is not set, look for .syncrc in BACKUPDIR
+    tmp_config=${tmp_config:-$tmp_backupdir/daily-01/.syncrc}
+    if [[ -z "$tmp_config" ]]; then
+        printf "%s: Missing configuration file.\n" "$CMDNAME"
+        exit 10
+    elif [[ ! -r "$tmp_config" ]]; then
+        printf "%s: Cannot open %s file. Exiting.\n" "$CMDNAME" "$tmp_config"
+        exit 9
+    fi
+
+    # shellcheck source=sync-conf-example.sh
+    source "$tmp_config"
+    [[ -n "$SOURCEDIR" ]] && ROOTDIR="$SOURCEDIR"
+
+    [[ -n "$tmp_backupdir" ]] && BACKUPDIR="$tmp_backupdir"
+    [[ -n "$tmp_destdir" ]] && TARGETDIR="$tmp_destdir"
+    [[ -n "$tmp_rootdir" ]] && ROOTDIR="$tmp_rootdir"
+    return 0
+}
+
+check_paths() {
+    local tmp
+
+    [[ -z "$BACKUPDIR" ]] && printf "%s: backup directory is not set.\n" "$CMDNAME" && \
+        ! usage
+    [[ -z "$ROOTDIR" ]] && printf "%s: source directory is not set.\n" "$CMDNAME" && \
+        ! usage
+    if [[ -n "$TARGETDIR" ]]; then
+        if [[ ! -e $TARGETDIR ]]; then
+            log "Creating destination directory %s." "$TARGETDIR"
+            mkdir "$TARGETDIR"
+        fi
+    else
+        tmp="$(basename "$TARGET")"
+        TARGETDIR="$(mktemp -d /tmp/"$tmp"-XXXXXXXX)"
+        log "%s target directory created." "$TARGETDIR"
+    fi
+    log "ROOTDIR=[%s]" "$ROOTDIR"
+    log "BACKUPDIR=[%s]" "$BACKUPDIR"
+    log "TARGETDIR=[%s]" "$TARGETDIR"
+    log "TARGET=[%s]" "$TARGET"
+    for var in BACKUPDIR TARGETDIR; do
+        [[ $var = ROOTDIR && -z $RESOLVETARGET ]] && continue
+        if [[ ! -d "${!var}" ]]; then
+            printf "%s is not a directory.\n" "$var"
+            exit 1
+        fi
+    done
+    if ! pushd "$TARGETDIR" > /dev/null; then
+        printf "cannot change to directory %s.\n" "$TARGETDIR"
+        exit 1
+    fi
+    # remove existing files
+    if [[ -n "$(ls -A .)" ]]; then
+        log "Cleaning existing directory %s." "$TARGETDIR"
+        for target in *; do
+            rm "$target"
+        done
+    fi
+    return 0
+}
+
+parse_opts "$@"
+check_paths
+
+# add missing directories
+declare -a DIRS
+DIRS=("$BACKUPDIR"/{dai,week,month,year}ly-[0-9][0-9])
+log "DIRS=%s" "${DIRS[*]}"
+
+for file in "${DIRS[@]}"; do
+    # src is file/dir in backup tree
+    _tmp=${TARGET#"$ROOTDIR"}
+    [[ $_tmp =~ ^/.*$ ]] || _tmp="/$_tmp"
+    src="$file$_tmp"
+    #printf "src=%s\n" "$src"
+    if [[ ! -e $src ]]; then
+        log "Skipping non-existing %s" "$src"
+        continue
+    fi
+    #ls -li "$src"
+
+    # last modification time in seconds since epoch
+    inode=$(stat --dereference --printf="%i" "$src")
+    date=$(stat --printf="%Y" "$src")
+    date_backup=$(stat --dereference --printf="%Y" "$file")
+    # target is daily-01, etc...
+    #target=$(date --date="@$date" "+%Y-%m-%d %H:%M")" - ${file#"$BACKUPDIR/"}"
+    target="${file#"$BACKUPDIR/"}"
+
+    #printf "target=[%s] src=[%s]\n" "$target" "$src"
+    if [[ -n $EXCLUDE && $target =~ $EXCLUDE ]]; then
+        log "Skipping %s\n" "$file"
+        continue
+    fi
+    if [[ -z $UNIQUE || ! -v INODES[$inode] ]]; then
+        log "Adding %s inode %s (%s)" "$file" "$inode" "$target"
+        ln -fs "$src" "$TARGETDIR/$target"
+    else
+        log "Skipping duplicate inode %s (%s)" "$inode" "$target"
+    fi
+    INODES[$inode]=${INODES[$inode]:-$date}
+    INODES[backup-$inode]=${INODES[backup-$inode]:-$date_backup}
+done
+
+if [[ -n "$(ls -A .)" ]]; then
+    printf "backup date      (backup)|last changed|inode|size|perms|type|path\n"
+    # for file in {dai,week,month,year}ly-[0-9][0-9]; do
+    for symlink in *; do
+        file=$(readlink "$symlink")
+        #printf "file=<%s> link=<%s>\n" "$file" "$symlink" >&2
+        inode=$(stat --printf="%i" "$file")
+        type=$(filetype "$file")
+        #links=$(stat --printf="%h" "$file")
+        date=$(date --date="@${INODES[$inode]}" "+%Y-%m-%d %H:%M")
+        backup_date=$(date --date="@${INODES[backup-$inode]}" "+%Y-%m-%d %H:%M")
+        size=$(stat --printf="%s" "$file")
+        perms=$(stat --printf="%A" "$file")
+        printf "%s (%s)|" "$backup_date" "$symlink"
+        printf "%s|" "$date"
+        #printf "%s|" "$links"
+        printf "%s|" "$inode"
+        printf "%s|" "$size"
+        printf "%s|" "$perms"
+        printf "%s|" "$type"
+        printf "%s\n" "$file"
+        # ls -lrt "$TARGETDIR"
+    done | sort -r
+fi | column -t -s\|
+
+printf "temporary files directory is: %s\n" "$PWD"
+exit 0

bash/sync.sh

@@ -1,63 +1,86 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # sync.sh - a backup utility using ssh/rsync facilities.
 #
-# (C) Bruno Raoult ("br"), 2007-2021
-# Licensed under the Mozilla Public License (MPL) version 2.0.
+# (C) Bruno Raoult ("br"), 2007-2022
+# Licensed under the GNU General Public License v3.0 or later.
 # Some rights reserved. See COPYING.
 #
-# You should have received a copy of the Mozilla Public License along with this
-# program.  If not, see <https://www.mozilla.org/en-US/MPL>
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
 #
-# SPDX-License-Identifier: MPL-2.0 <https://spdx.org/licenses/MPL-2.0.html>
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
 #
+#%MAN_BEGIN%
 # NAME
 #       sync.sh - a backup utility using ssh/rsync facilities.
 #
 # SYNOPSIS
-#       sync.sh [-ymwdznt] CONFIG
+#       sync.sh [OPTIONS] [SOURCE_DIR]
 #
 # DESCRIPTION
-#       Performs a backup to a local or remote destination, keeping different
+#       Perform a backup to a local or remote destination, keeping different
 #       versions (daily, weekly, monthly, yearly). All options can be set in
-#       CONFIG file, which is mandatory.
+#       a mandatory configuration file, which is either SOURCE_DIR/.syncrc,
+#       either set with the '-c' option. See option '-c' below.
+#       The synchronization is make with rsync(1), and only files changed or
+#       modified are actually copied; files which are identical with previous
+#       backup are hard-linked to previous one.
 #
 # OPTIONS
-#       -y, -m, -w, -d
-#          yearly/monthly/weekly/daily backup. If none of these options is set,
-#          and none of the corresponding variables set to "y" in configuration
+#       -a PERIOD
+#          Indicate which backup(s) should be done. PERIOD is a string composed
+#          of one or more of 'y', 'm', 'w', and 'd', indicating respectively
+#          yearly, monthly, weekly and daily backups.
+#          Multiple -a may appear. For example, if we wish to perform a daily,
+#          monthly, and yearly backup, we can use syntax like :
+#              -a m -a y -a d
+#              -adm -ay
+#              -a ymd
+#          If this option is not used, and none of the equivalent variables
+#          (YEARLY, MONTHY, WEEKLY, DAILY) is set to "y" in configuration
 #          file, the script will determine itself what should be done,
 #          depending on the current day or date: daily backup every day,
 #          weekly every sunday, monthly every first day of month, and yearly
 #          every Jan 1st.
-#       -n
-#          do not send mail report (which is the default if MAILTO environment
-#          is set). Practically, this option only unsets MAILTO.
-#       -f
-#          filter some rsync output, such as hard and soft links, dirs, etc.
-#       -r
-#          resume an interrupted transfer (rsync --partial option). It should
-#          be safe to use this option, as it has no effect in usual case.
-#       -z
-#          enable rsync compression. Should be used when the transport is more
-#          expensive than CPU (typically slow connections).
-#       -u
-#          will use numeric IDs (uid and gid) instead of usernames/groupnames.
-#          This could be preferable in case of backup, to avoid any issue when
-#          getting back the file (for instance via a mount).
-#       -v
-#          adds sub-tasks information, with timestamps.
+#       -c CONFIG
+#          Use CONFIG as configuration file. See sync-conf-example.sh.
+#          If this option is used, the script will ignore SOURCE_DIR/.syncrc
+#          file.
 #       -D
-#          by default, this script will re-route all outputs (stdout and stderr)
+#          By default, this script re-routes all outputs (stdout and stderr)
 #          to a temporary file after basic initialization (mainly options
 #          checks and configuration file evaluation), so that we can format
 #          the output before displaying or mailing it.
 #          This option disables this redirection. It is useful (together with
 #          bash's -x option) when some errors are difficult to track.
+#       -f
+#          Filter some rsync output, such as hard and soft links, dirs, etc.
+#       -l
+#          Keep log file (usually /tmp/sync-log-PID).
+#       -m
+#          Display a "man-like" description and exit.
+#       -n
+#          Do not send mail report (which is the default if MAILTO environment
+#          is set). Practically, this option only unsets MAILTO.
+#       -r
+#          Resume an interrupted transfer (rsync --partial option). It should
+#          be safe to use this option, as it has no effect in usual case.
+#       -u
+#          Use numeric IDs (UID and GID) instead of usernames/groupnames. This
+#          could be preferable in case of backup, to avoid any issue when
+#          getting back the file (for instance via a mount).
+#       -v
+#          Add sub-tasks information, with timestamps. This option is currently
+#          not implemented.
+#       -z
+#          Enable rsync compression. Should be used when the transport is more
+#          expensive than CPU (typically slow connections).
+#       -Z
+#          By default, if gzip utility is available, the email log attachment
+#          is compressed. This option will prevent any compression.
 #
 # GENERAL
-#       Ensure your ssh setup is correct: You must be able to ssh the target
-#       machine without password.
 #       You should avoid modifying variables in this script.
 #       Instead, use the configuration file, whenever possible.
 #
@@ -67,9 +90,31 @@
 #       By default, the output is displayed (or mailed) when the script exits.
 #       The -D option allows to get real-time output.
 #
+# PREREQUISITES
+#       The following must be installed, configured, and within your PATH :
+#       ssh
+#          Ensure your ssh setup is correct: You must be able to ssh the target
+#          machine without password.
+#       sendmail/postfix (or any MTA providing the sendmail command)
+#          Your MTA must be properly configured to send emails. For example
+#          you should receive an email with the following command :
+#             echo "Subject: sendmail test" | sendmail -v youremail@example.com
+#
+#       Additionnaly, you will also need the "base64" and "gzip" utilities.
+#
+#       NOTE: If you run this script via cron(8), please remember that PATH is
+#       different. For example, on some systems, cron's default PATH is
+#       "/usr/bin:/bin". Should sendmail binary be in /usr/sbin on your system,
+#       you will have to change PATH in your crontab.
+#
 # CONFIGURATION FILE
 #       TODO: Write documentation. See example (sync-conf-example.sh).
 #
+# AUTHOR
+#       Bruno Raoult.
+#
+#%MAN_END%
+#
 # BUGS
 #       Many.
 #       This was written for a "terastation" NAS server, which is a kind of
@@ -87,7 +132,6 @@
 #       - replace y/n values with empty/not-empty. A step to avoid config file
 #       - set default compress value on local/non-local. Step to avoid config
 #         file
-#       - replace y/m/w/d with numerical values ? Step to avoid config file
 #       - manage more errors (instead of relying on traps)
 #       - the deletion of oldest backup directories takes ages. This could be
 #         avoided (for example we could move them to a temp dir and remove it
@@ -100,23 +144,21 @@
 #         destination from the previous backup, and perform a usual backup
 #         on this new directory. This should be easy, but my guess is that
 #         it could be slower (1 first pass on server is added before the
-#         normal backup.
-#       - replace getopts(1) to have a better options parsing. GNU's getopt(1)
-#         could be an option, but not available everywhere (for example on
-#         MacOS). Likely impossible to keep this script portable.
-#
-# AUTHOR
-#       Bruno Raoult.
-#
+#         normal backup).
+#       - replace bash's getopts for a better options parsing tool, such as
+#         GNU's getopt(1) could be an option, but not available everywhere
+#         (for example on MacOS). Likely impossible to keep this script portable.
 #
 
-#########################  options default values.
-# These ones can be set by command-line.
-# They can also be overwritten in configuration file (prefered option).
-YEARLY=n                        # (-y) yearly backup (y/n)
-MONTHLY=n                       # (-m) monthly backup (y/n)
-WEEKLY=n                        # (-w) weekly backup (y/n)
-DAILY=n                         # (-d) daily backup (y/n)
+###############################################################################
+#########################  options default values
+###############################################################################
+# These ones can be set by command-line and in configuration file.
+# priority is given to configuration file.
+YEARLY=n                        # (-ay) yearly backup (y/n)
+MONTHLY=n                       # (-am) monthly backup (y/n)
+WEEKLY=n                        # (-aw) weekly backup (y/n)
+DAILY=n                         # (-ad) daily backup (y/n)
 FILTERLNK=n                     # (-f) rsync logs filter: links, dirs... (y/n)
 RESUME=n                        # (-r) resume backup (y/n)
 COMPRESS=""                     # (-z) rsync compression
@@ -124,129 +166,175 @@ NUMID=""                        # (-u) use numeric IDs
 #VERBOSE=0                       # TODO: (-v) logs level (0/1)
 DEBUG=n                         # (-D) debug: no I/O redirect (y/n)
 MAILTO=${MAILTO:-""}            # (-n) mail recipient. -n sets it to ""
+ZIPMAIL="gzip"                  # (-Z) zip mail attachment
+KEEPLOGFILE=n                   # (-l) keep log file
 
-# options not available on command line, but settable in config  file.
+# options only settable in config  file.
 NYEARS=3                        # keep # years (int)
 NMONTHS=12                      # keep # months (int)
-NWEEKS=4                        # keep # weeks (int)
-NDAYS=7                         # keep # days (int)
-RSYNCOPTS=""                    # other rsync options
-SOURCEDIR="."                   # source dir
-DESTDIR="."                     # destination dir
+NWEEKS=6                        # keep # weeks (int)
+NDAYS=10                        # keep # days (int)
+declare -a RSYNCOPTS=()         # other rsync options
+SOURCEDIR=""                    # source dir
+SERVER=""                       # backup server
+DESTDIR=""                      # destination dir
 MODIFYWINDOW=1                  # accuracy for mod time comparison
 
 # these 2 functions can be overwritten in data file, to run specific actions
 # just before and after the actual sync
-function beforesync () {
-    log calling default beforesync...
+beforesync() {
+    log "calling default beforesync..."
 }
-function aftersync () {
-    log calling default aftersync...
+aftersync() {
+    log "calling default aftersync..."
 }
 
 # internal variables, cannot (and *should not*) be changed unless you
 # understand exactly what you do.
 # Some variables were moved into the code (example: in the log() function),
 # for practical reasons, the absence of associative arrays being one of them.
+SCRIPT="$0"                     # full path to script
+CMDNAME=${0##*/}                # script name
+PID=$$                          # current pricess PID
 LOCKED=n                        # indicates if we created lock file.
-SUBJECT="${0##*/} ${*##*/}"     # mail subject (removes paths)
-ERROR=0                         # set by error_handler when called
 STARTTIME=$(date +%s)           # time since epoch in seconds
+HOSTNAME="$(hostname)"
+declare -A ERROR_STR=(          # error strings
+    [0]="ok"
+    [1]="error"
+    [2]="missing command"
+    [3]="source directory error"
+    [4]="could not create lock file"
+    [5]="could not rotate backup directories"
+    [6]="partial backup detected"
+    [7]="rsync error"
+    [8]="invalid command line"
+    [9]="missing configuration file"
+    [10]="missing destination directory"
+    [11]="cannot acquire lock"
+    [12]="cannot determine PID of locked directory"
+    [13]="error in rotation"
+    [14]="could not set modification time on target"
+    [15]="error on non-daily tree copy"
+)
 
-usage () {
-    echo "usage: ${0##*/} [-ymwdnfrzuD]" config-file
-    exit 1
+###############################################################################
+#########################  helper functions
+###############################################################################
+man() {
+    sed -n '/^#%MAN_BEGIN%/,/^#%MAN_END%$/{//!s/^#[ ]\{0,1\}//p}' "$SCRIPT" | more
 }
 
-# command-line options parsing.
-OPTIND=1
-while getopts ymwdfrnzuD todo
-do
-    case "${todo}" in
-        y)  YEARLY=y;;
-        m)  MONTHLY=y;;
-        w)  WEEKLY=y;;
-        d)  DAILY=y;;
-        f)  FILTERLNK=y;;
-        r)  RESUME=y;;
-        n)  MAILTO="";;
-        z)  COMPRESS=-y;;       # rsync compression. Depends on net/CPU perfs
-        u)  NUMID="--numeric-ids";;
-        D)  DEBUG=y;;
-        *)  usage;;
-    esac
-done
-# Now check remaining argument (configuration file), which should be unique,
-# and read the file.
-shift $((OPTIND - 1))
-(( $# != 1 )) && usage
-CONFIG="$1"
-if [[ ! -f "$CONFIG" ]]; then
-    echo "No $CONFIG file."
-    usage
-fi
-source "$CONFIG"
-
-# we set backups to be done if none has been set yet (i.e. none is "y").
-# Note: we use the form +%-d to avoid zero padding.
-#       for bash, starting with 0 => octal => 08 is invalid
-if ! [[ "${DAILY}${WEEKLY}${MONTHLY}${YEARLY}" =~ .*y.* ]]; then
-    (( $(date +%u) == 7 )) && WEEKLY=y
-    (( $(date +%-d) == 1 )) && MONTHLY=y
-    (( $(date +%-d) == 1 && $(date +%-m) == 1 )) && YEARLY=y
-    DAILY=y
-fi
-
-# set final variables values
-LOCKFILE=".sync-${SERVER}-${CONFIG##*/}.lock"
+usage() {
+    printf "usage: %s [-a PERIOD][-c CONFIG][-DflmnruvzZ] [backup_directory]\n" \
+           "$CMDNAME"
+    exit 8
+}
 
 # log function
 # parameters:
 # -l, -s: long, or short prefix (default: none). Last one is used.
 # -t: timestamp
 # -n: no newline
+# This function accepts either a string, either a format string followed
+# by arguments :
+#   log -s "%s" "foo"
+#   log -s "foo"
 log() {
-    timestr=""
-    prefix=""
-    opt=y
-    newline=y
-    while [[ $opt = y ]]; do
-        case $1 in
-            -l) prefix=$(printf "*%.s" {1..30});;
-            -s) prefix=$(printf "*%.s" {1..5});;
-            -n) newline=n;;
-            -t) timestr=$(date "+%F %T%z - ");;
-            *) opt=n;;
+    local timestr="" prefix="" newline=y todo OPTIND
+    while getopts lsnt todo; do
+        case $todo in
+            l) prefix=$(printf "*%.s" {1..30})
+               ;;
+            s) prefix=$(printf "*%.s" {1..5})
+               ;;
+            n) newline=n
+               ;;
+            t) timestr=$(date "+%F %T%z ")
+               ;;
+            *) ;;
         esac
-        [[ $opt = y ]] && shift
     done
+    shift $((OPTIND - 1))
     [[ $prefix != "" ]] && printf "%s " "$prefix"
-    printf "%s%s" "$timestr" "$*"
-    [[ $newline = y ]] && echo
+    [[ $timestr != "" ]] && printf "%s" "$timestr"
+    # shellcheck disable=SC2059
+    printf "$@"
+    [[ $newline = y ]] && printf "\n"
     return 0
 }
 
-# After these basic initializations, errors will be managed by the
-# following handler. It is better to do this before the redirections below.
-error_handler() {
-    ERROR=$2
-    echo "FATAL: Error line $1, exit code $2. Aborting."
-    exit "$ERROR"
+# prints out and run a command. Used mainly for rsync debug.
+echorun () {
+    log "%s" "$*"
+    "$@"
+    return $?
 }
 
-trap 'error_handler $LINENO $?' ERR SIGHUP SIGINT SIGTERM
+# lock system
+lock_lock() {
+    local opid pidfile="$LOCKDIR/pid"
+    #log -n "Setting lock: "
+    log "Acquire lock (%s), pid=%d" "$LOCKDIR" "$PID"
+    if [[ -d "$LOCKDIR" ]]; then
+        if [[ -r "$pidfile" ]]; then
+            read -r opid < "$pidfile"
+            if ps -p "$opid" &> /dev/null; then
+                log "PID %d (in %s) still active. Exiting." "$opid" "$pidfile"
+                exit 11
+            fi
+            log "Stale lock file found (pid=%d), forcing unlock... " "$opid"
+            lock_unlock -f
+            log "Re-Acquire lock (%s), pid=%d" "$LOCKDIR" "$PID"
+        else
+            log "lockdir exists with unknown PID"
+            exit 12
+        fi
+    fi
+    if ! mkdir "$LOCKDIR"; then
+        log "Cannot create lock file. Exiting."
+        exit 4
+    fi
+    printf "%d\n" "$PID" >> "$pidfile"
+    LOCKED=y
+    return 0
+}
+
+lock_unlock() {
+    local force=n
+    [[ $# == 1 && $1 == -f ]] && force=y
+    if [[ "$force" = y || "$LOCKED" = y ]]; then
+        if [[ "$force" = y ]]; then
+            log "Forced lock release (%s)" "$LOCKDIR"
+        else
+            log "Release lock (%s)" "$LOCKDIR"
+        fi
+        rm -vrf "$LOCKDIR"
+    else
+        log "Nothing to unlock (%s)" "$LOCKDIR"
+    fi
+    return 0
+}
+
+# Error handler.After these basic initializations, errors will be managed by the
+# following handler. It is better to do this before the redirections below.
+error_handler() {
+    local line="$1" err="$2"
+    printf "FATAL: Error line %s, exit code %s. Aborting.\n" "$line" "$err"
+    exit "$err"
+}
 
 exit_handler() {
+    local -i status="$?"
+    local error="${ERROR_STR[$status]}"
+    local subject="$CMDNAME: $SOURCEDIR on $HOSTNAME"
     # we dont need lock file anymore (another backup could start from now).
-    log "exit_handler LOCKED=$LOCKED"
-    #if [[ "$LOCKED" = y ]]; then
-    rm --dir --verbose "${LOCKFILE}"
-    #fi
+    lock_unlock
 
-    if (( ERROR == 0 )); then
-        SUBJECT="Successful $SUBJECT"
+    if (( status == 0 )); then
+        subject="$subject (Success)"
     else
-        SUBJECT="Failure in $SUBJECT"
+        subject="$subject (Failure: $error)"
     fi
 
     log -l -t "Ending backup."
@@ -255,149 +343,372 @@ exit_handler() {
         # restore stdout (not necessary), set temp file as stdin, close fd 3.
         # remove temp file (as still opened by stdin, will still be readable).
         exec 1<&3 3>&- 0<"$TMPFILE"
-        rm -f "$TMPFILE"
+        [[ $KEEPLOGFILE = n ]] && rm -f "$TMPFILE"
     else
-        echo 222
         exec 0<<<""             # force empty input for the following
     fi
 
-    # Warning: no logs allowed here (before next braces), as stdout is no
-    # more handled the final way.
+    SECS=$(( $(date +%s) - STARTTIME ))
+
+    # Warning: no logs allowed here (before next braces), as stdout will not
+    # be handled/filtered.
     {
-        SECS=$(($(date +%s)-STARTTIME))
-
         # we write these logs here so that they are on top if no DEBUG.
-        log "Exit code: $ERROR"
-        log "$(printf "Elapsed time: $SECS seconds (%d:%02d:%02d)\n\n" \
-            $((SECS/3600)) $((SECS%3600/60)) $((SECS%60)))"
+        printf "%s: Exit code: %d (%s) " "$CMDNAME" "$status" \
+               "${ERROR_STR[$status]}"
 
+        printf "in %d seconds (%d:%02d:%02d)\n" \
+               $((SECS)) $((SECS/3600)) $((SECS%3600/60)) $((SECS%60))
+
+        [[ $KEEPLOGFILE = y ]] && printf "log file kept at: %s\n" "$TMPFILE"
+        printf "\n"
         if [[ -n $FILTERLNK ]]; then
-            grep -vE "^(hf|cd|cL)[ \+]" ;
+            grep -vE "^(hf|cd|cL)[ \+]"
         else
-            cat ;
+            cat
         fi
     } |
     {
         if [[ -n $MAILTO ]]; then
-            mail -s "${SUBJECT}" "${MAILTO}";
+            {
+                MIMESTR="FEDCBA_0987654321"
+
+                # email header
+                printf "To: %s\n" "$MAILTO"
+                #printf "From: %s" "$MAILTO"
+                printf "Subject: %s\n" "$subject"
+                printf "MIME-Version: 1.0\n"
+                printf 'Content-Type: multipart/mixed; boundary="%s"\n' "$MIMESTR"
+                printf "\n"
+
+                # We write a short information in email's body
+                printf "\n--%s\n" "$MIMESTR"
+                printf 'Content-Type: text/plain; charset=UTF-8\n'
+                printf '\n'
+
+                # send first lines in message body (until the mark line or EOF)
+                has_mark_line=0
+                while read -r line; do
+                    if [[ $line =~ ^\*+\ Mark$ ]]; then
+                        has_mark_line=1
+                        break
+                    fi
+                    printf "%s\n" "$line"
+                done
+
+                # we prepare attachment only if a mark line was found
+                if ((  has_mark_line == 1 )); then
+                    printf "\n--%s\n" "$MIMESTR"
+                    if [[ "$ZIPMAIL" == cat ]]; then
+                        printf 'Content-Type: text/plain; charset=UTF-8\n'
+                        printf 'Content-Disposition: attachment; filename="sync-log.txt"\n'
+                    else
+                        printf "Content-Type: application/gzip\n"
+                        printf 'Content-Disposition: attachment; filename="sync-log.txt.gz"\n'
+                    fi
+                    printf "Content-Transfer-Encoding: base64\n"
+                    printf '\n'
+                    $ZIPMAIL | base64
+                fi
+                printf "\n--%s--\n" "$MIMESTR"
+            } | sendmail -it
         else
-            cat;
+            grep -vE "^\*+\ Mark$"
         fi
     }
 }
+
+###############################################################################
+#########################  Options/Environment setup
+###############################################################################
+# command-line parsing / configuration file read.
+parse_opts() {
+    local _config="" _backup_dir=""
+
+    OPTIND=0
+    shopt -s extglob                # to parse "-a" option
+    while getopts a:c:DflmnruvzZ todo; do
+        case "$todo" in
+            a)
+                # we use US (Unit Separator, 0x1F, control-_) as separator
+                # next line will add US before each char (including 1st one)
+                IFS=$'\x1F' read -ra periods <<< "${OPTARG//?()/$'\x1F'}"
+                # we skip 1st (empty) ellement of array
+                for period in "${periods[@]:1}"; do
+                    case "$period" in
+                        d) DAILY=y;;
+                        w) WEEKLY=y;;
+                        m) MONTHLY=y;;
+                        y) YEARLY=y;;
+                        *) printf '%s: unknown period "%s"\n' "$CMDNAME" "$period"
+                           usage
+                    esac
+                done
+                ;;
+            c)
+                _config="$OPTARG"
+                if [[ ! -f "$_config" ]]; then
+                    printf "%s: invalid %s configuration file\n" "$CMDNAME" "$_config"
+                    usage
+                fi
+                ;;
+            f)
+                FILTERLNK=y
+                ;;
+            r)
+                RESUME=y
+                ;;
+            l)
+                KEEPLOGFILE=y
+                ;;
+            m)
+                man
+                exit 0
+                ;;
+            n)
+                MAILTO=""
+                ;;
+            z)
+                COMPRESS=-y     # rsync compression. Depends on net/CPU perfs
+                ;;
+            u)
+                NUMID="--numeric-ids"
+                ;;
+            D)
+                DEBUG=y
+                ;;
+            Z)
+                ZIPMAIL="cat"
+                ;;
+            *)
+                usage
+                ;;
+        esac
+    done
+    # Now check remaining argument (backup directory)
+    shift $((OPTIND - 1))
+
+    (( $# > 1 )) && usage
+    if (( $# == 1 )); then
+        _backup_dir="$1"
+        if [[ ! -d $_backup_dir ]]; then
+            printf "%s: %s: not a directory\n" "$CMDNAME" "$_backup_dir"
+            usage
+        fi
+        [[ -f "$_backup_dir/.syncrc" ]] && _config=${_config:-"$_backup_dir/.syncrc"}
+    fi
+
+    # We do not know what to do...
+    [[ -z "$_config" ]] && usage
+
+    # see https://unix.stackexchange.com/questions/406216
+    CONFIG=$(realpath -sm "$_config")
+    if [[ -z "$CONFIG" ]]; then
+        printf "%s: Missing configuration file\n" "$CMDNAME"
+        exit 9
+    elif [[ ! -r "$CONFIG" ]]; then
+        printf "%s: Cannot open %s file\n" "$CMDNAME" "$CONFIG"
+        exit 9
+    fi
+    # shellcheck source=share/sync/sync-conf-example.sh
+    source "$CONFIG"
+
+    # _backup_dir takes precedence on SOURCEDIR (useless ?)
+    SOURCEDIR=${_backup_dir:-$SOURCEDIR}
+
+    LOCKDIR="/tmp/$CMDNAME-$HOSTNAME${SOURCEDIR////-}.lock"
+}
+
+parse_opts "$@"
+
+# we set backups to be done if none has been set yet (i.e. none is "y").
+# Note: we use the form +%-d to avoid zero padding :
+# for bash, starting with 0 => octal => 08 is invalid
+adjust_targets() {
+    if ! [[ "$DAILY$WEEKLY$MONTHLY$YEARLY" =~ .*y.* ]]; then
+        (( $(date +%u) == 7 )) && WEEKLY=y
+        (( $(date +%-d) == 1 )) && MONTHLY=y
+        (( $(date +%-d) == 1 && $(date +%-m) == 1 )) && YEARLY=y
+        DAILY=y
+    fi
+}
+
+adjust_targets
+
+# After these basic initializations, errors will be managed by the
+# following handler. It is better to do this before the redirections below.
+trap 'error_handler $LINENO $?' ERR SIGHUP SIGINT SIGTERM
 trap 'exit_handler' EXIT
 
+# activate exit on error
+# set -o errexit errtrace nounset pipefail
+
 # standard descriptors redirection.
 # if not DEBUG, save stdout as fd 3, and redirect stdout to temp file.
 # in case of DEBUG, we could close stdin, but there could be side effects,
 # such as ^C handling, etc... So we keep the keyboard available.
 if [[ $DEBUG = n ]]; then
-    TMPFILE=$(mktemp /tmp/sync-log.XXXXXX)
-    exec 3<&1 >"${TMPFILE}"     # no more output on screen from now.
+    TMPFILE=$(mktemp /tmp/sync-XXXXXXXX.log)
+    exec 3<&1 >"$TMPFILE"     # no more output on screen from now.
 fi
 exec 2>&1
-if [[ ! -d $SOURCEDIR ]]; then
-    log -s "Source directory (\"${SOURCEDIR}\") is not a valid directory."
-    error_handler $LINENO 1
-fi
-cd ${SOURCEDIR}
 
 # prepare list of backups, such as "daily 7 weekly 4", etc...
+# the order is important.
 TODO=()
-[[ $DAILY = y && $NDAYS -gt 0 ]]     && TODO+=(daily "$NDAYS")
-[[ $WEEKLY = y && $NWEEKS -gt 0 ]]   && TODO+=(weekly "$NWEEKS")
-[[ $MONTHLY = y && $NMONTHS -gt 0 ]] && TODO+=(monthly "$NMONTHS")
-[[ $YEARLY = y && $NYEARS -gt 0 ]]   && TODO+=(yearly "$NYEARS")
+[[ $DAILY   = y ]] && (( NDAYS   > 0 )) && TODO+=(daily   "$NDAYS")
+[[ $WEEKLY  = y ]] && (( NWEEKS  > 0 )) && TODO+=(weekly  "$NWEEKS")
+[[ $MONTHLY = y ]] && (( NMONTHS > 0 )) && TODO+=(monthly "$NMONTHS")
+[[ $YEARLY  = y ]] && (( NYEARS  > 0 )) && TODO+=(yearly  "$NYEARS")
+
+log -l -t "Starting %s" "$CMDNAME"
+log "Bash version: %s.%s.%s" "${BASH_VERSINFO[@]:0:3}"
+log "Hostname: %s" "$HOSTNAME"
+log "Operating System: %s on %s" "$(uname -sr)" "$(uname -m)"
+log "Config : %s\n" "$CONFIG"
+log "Src dir: %s" "$SOURCEDIR"
+log "Dst dir: %s" "$SERVER:$DESTDIR"
+log "Lock dir: %s" "$LOCKDIR"
+log "Actions: %s" "${TODO[*]}"
+if (( ${#RSYNCOPTS[@]} )); then
+    log -n "Rsync additional options (%d): " "${#RSYNCOPTS[@]}"
+    for opt in "${RSYNCOPTS[@]}"; do
+        log -n '\"%s\" ' "$opt"
+    done
+    log ""
+else
+    log "Rsync additional options : None."
+fi
+
+log -n "Mail recipient: "
+# shellcheck disable=SC2015
+[[ -n "$MAILTO" ]] && log "$MAILTO" || log "<unset>"
+# shellcheck disable=SC2015
+log -n "Compression: " && [[ $ZIPMAIL = gzip ]] && log "gzip" || log "none"
+
+# check availability of necessary commands
+declare -a cmdavail=()
+declare error=0
+log -n "Checking for commands : "
+for cmd in rsync base64 sendmail gzip; do
+    log -n "%s..." "$cmd"
+    if type -P "$cmd" > /dev/null; then
+        log -n "ok "
+    else
+        (( error++ ))
+        log -n "NOK "
+        case "$cmd" in
+            gzip)
+                log -n "(compression disabled) "
+                ZIPMAIL="cat"
+                (( error-- ))   # Not an error
+               ;;
+            sendmail)
+                MAILTO=""       # to get some output in cron
+                ;;
+        esac
+        cmdavail+=("$cmd")
+    fi
+done
+log ""
+(( ${#cmdavail[@]} )) && log -s "Please install the following programs: %s." \
+                             "${cmdavail[*]}"
+(( error > 0 )) && exit 2
+unset cmdavail
+unset error
+
+# all logs from this point will be in email attachment
+log -s "Mark"                   # to separate email body
+
+log -l -t "Starting backup"
+# create lock file
+lock_lock
 
-log -l -t "Starting backup."
-log "Config : ${CONFIG}"
-log "Src dir: ${SOURCEDIR}"
-log "Dst dir: ${SERVER}:${DESTDIR}"
-log "Actions: ${TODO[@]}"
 
 # select handling depending on local or networked target (ssh or not).
 if [[ $SERVER = local ]]; then  # local backup
     DOIT=""
-    DEST=${DESTDIR}
+    DEST="$DESTDIR"
 else                            # remote backup
-    DOIT="ssh ${SERVER}"
-    DEST="${SERVER}:${DESTDIR}"
+    DOIT="ssh $SERVER"
+    DEST="$SERVER:$DESTDIR"
 fi
 
 # commands and specific variables.
-EXIST="${DOIT} test -e"
-MOVE="${DOIT} mv"
-REMOVE="${DOIT} rm -rf"
-COPYHARD="${DOIT} rsync -ar"
-
-# prints out and run a command. Used mainly for rsync debug.
-echorun () {
-    log "$@"
-    "$@"
-    return $?
-}
+EXIST="$DOIT test -e"
+MOVE="$DOIT mv"
+REMOVE="$DOIT rm -rf"
+COPYHARD="$DOIT rsync -ar"
+TOUCH="$DOIT touch"
 
 # rotate files. arguments are a string and a number. For instance $1=weekly,
 # $2=3.
 # we first build a list from $2 to zero, with 2 padded digits: 03 02 01 00
 # then we remove $1-03, and move $1-02 to $1-03, $1-01 to $1-02, etc...
-rotate-files () {
-    files=( $(seq -f "${DESTDIR}/${1}-%02g" "${2}" -1 0) )
-    log -s -t -n "${files[0]##*/} deletion... "
-    status=0
-    ${REMOVE} "${files[0]}" || status=$?
-    if (( status != 0 )); then
+rotate-files() {
+    # shellcheck disable=SC2207
+    local -a files=( $(seq -f "$DESTDIR/$1-%02g" "$2" -1 0) )
+    log -s -t -n "deleting %s... " "${files[0]##*/}"
+    if ! $REMOVE "${files[0]}"; then
         # this should never happen.
         # But I saw this event in case of a file system corruption. Better
         # is to stop immediately instead of accepting strange side effects.
-        if ${EXIST} "${files[0]}" ; then
-            log -s "Could not remove ${files[0]}. This SHOULD NOT happen."
-            error_handler $LINENO ${status}
+        if $EXIST "${files[0]}" ; then
+            log -s "Could not remove %s. This SHOULD NOT happen." "${files[0]}"
+            exit 5
         fi
     fi
     log "done."
 
-    log -s -t -n "${1} rotation... "
-    while (( ${#files[@]} > 1 ))
-    do
-        if ${EXIST} "${files[1]}" ; then
-            [[ $DEBUG = y ]] && log -n "${files[1]:(-2)} "
-            ${MOVE} "${files[1]}" "${files[0]}"
+    log -s -t -n "rotating " "$1"
+    while (( ${#files[@]} > 1 )); do
+        if $EXIST "${files[1]}" ; then
+            log -n "%s... " "${files[1]##*/}"
+            if ! $MOVE "${files[1]}" "${files[0]}"; then
+                log "error"
+                exit 13
+            fi
+
         fi
-        unset files[0]          # shift and pack array
+        unset "files[0]"        # shift and pack array
         files=( "${files[@]}" )
     done
     log "done."
     return 0
 }
 
-# create lock file
-if ! mkdir "${LOCKFILE}"; then
-    log -s  "Cannot create lock file. Exiting."
-    error_handler $LINENO 1
+if [[ ! -d "$SOURCEDIR" ]]; then
+    log -s "Invalid source directory (%s)." "$SOURCEDIR"
+    exit 3
+fi
+if ! cd "$SOURCEDIR"; then
+    log -s "Cannot cd to %s." "$SOURCEDIR"
+    exit 3
+fi
+if ! $EXIST "$DESTDIR"; then
+    log -s 'destination directory (%s) missing.' "$DESTDIR"
+    exit 10
 fi
-LOCKED=y
 
 # main loop.
-while [[ ${TODO[0]} != "" ]]
-do
+while [[ ${TODO[0]} != "" ]]; do
     # these variables to make the script easier to read.
     todo="${TODO[0]}"           # daily, weekly, etc...
     keep="${TODO[1]}"           # # of versions to keep for $todo set
-    todop="${DESTDIR}/${todo}"  # prefix for backup (e.g. "destdir/daily")
-    tdest="${todop}-00"         # target full path (e.g. "destdir/daily-00")
-    ldest="${DESTDIR}/daily-01" # link-dest dir (always daily-01)
+    todop="$DESTDIR/$todo"      # prefix for backup (e.g. "destdir/daily")
+    tdest="$todop-00"           # target full path (e.g. "destdir/daily-00")
+    ldest="$DESTDIR/daily-01"   # link-dest dir (always daily-01)
 
-    log -l -t "${todo} backup..."
+    log -l -t "%s backup..." "$todo"
 
     # check if target (XX-00) directory exists. If yes, we must have the
     # resume option to go on.
-    if ${EXIST} "${tdest}"; then
+    if $EXIST "$tdest"; then
         if [[ $RESUME = n ]]; then
-            log -s "${tdest} already exists, and no \"resume\" option."
-            error_handler $LINENO 1
+            log -s '%s already exists, and no "resume" option.' "$tdest"
+            exit 6
         fi
-        log -s "Warning: Resuming ${todo} partial backup.".
+        log -s "Warning: Resuming %s partial backup." "$todo"
     fi
 
     # daily backup.
@@ -413,34 +724,41 @@ do
         status=0
         echorun rsync \
             -aHixv \
-            "${FILTER}" \
-            ${RSYNCOPTS} \
-            ${COMPRESS} \
-            ${NUMID} \
+            "${RSYNCOPTS[@]}" \
+            $COMPRESS \
+            $NUMID \
             --delete \
             --delete-during \
             --delete-excluded \
-            --modify-window=${MODIFYWINDOW} \
+            --modify-window=$MODIFYWINDOW \
             --partial \
-            --link-dest="${ldest}" \
+            --link-dest="$ldest" \
             . \
-            "${DEST}/daily-00" || status=$?
+            "$DEST/daily-00" || status=$?
         # error 24 is "vanished source file", and should be ignored.
         if (( status != 24 && status != 0)); then
-            error_handler $LINENO $status
+            log -s "rsync error %d" "$status"
+            exit 7
+        fi
+        if ! $TOUCH "$tdest"; then
+            log -s "cannot change %s modification time (error %d)" \
+                "$DEST/daily-00" "$status"
+            exit 14
         fi
         aftersync               # script to run after the sync
-    else                        # non-daily case.
-        status=0
-        ${EXIST} "${ldest}" || status=$?
-        if ((status == 0 )); then
-            log -s -t "${tdest} update..."
-            ${COPYHARD} --link-dest="${ldest}" "${ldest}/" "${tdest}"
+    else                        # non-daily case
+        if $EXIST "$ldest"; then
+            # if ((status == 0 )); then
+            log -s -t "%s update..." "$tdest"
+            if ! $COPYHARD --link-dest="$ldest" "$ldest/" "$tdest"; then
+                log -s "copyhard error %d" "$status"
+                exit 15
+            fi
         else
-            log "No ${ldest} directory. Skipping ${todo} backup."
+            log "No %s directory. Skipping %s backup." "$ldest" "$todo"
         fi
     fi
-    rotate-files "${todo}" "${keep}"
+    rotate-files "$todo" "$keep"
 
     # shift and pack TODO array
     unset 'TODO[0]' 'TODO[1]'

bash/trans.sh

@@ -2,14 +2,14 @@
 #
 # trans.sh - Translate words using linguee.com.
 #
-# (C) Bruno Raoult ("br"), 2021
-# Licensed under the Mozilla Public License (MPL) version 2.0.
+# (C) Bruno Raoult ("br"), 2021-2022
+# Licensed under the GNU General Public License v3.0 or later.
 # Some rights reserved. See COPYING.
 #
-# You should have received a copy of the Mozilla Public License along with this
-# program.  If not, see <https://www.mozilla.org/en-US/MPL>
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
 #
-# SPDX-License-Identifier: MPL-2.0 <https://spdx.org/licenses/MPL-2.0.html>
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
 #
 # Options: See usage function in code below.
 

c/COPYING

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights.  Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received.  You must make sure that they, too, receive
+or can get the source code.  And you must show them these terms so they
+know their rights.
+
+  Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+  For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software.  For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+  Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so.  This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software.  The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable.  Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products.  If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+  Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary.  To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as "you".  "Licensees" and
+"recipients" may be individuals or organizations.
+
+  To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+  A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+  To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+  To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+  An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License.  If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+  1. Source Code.
+
+  The "source code" for a work means the preferred form of the work
+for making modifications to it.  "Object code" means any non-source
+form of a work.
+
+  A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+  The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form.  A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+  The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities.  However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work.  For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+  The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+  The Corresponding Source for a work in source code form is that
+same work.
+
+  2. Basic Permissions.
+
+  All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met.  This License explicitly affirms your unlimited
+permission to run the unmodified Program.  The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work.  This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+  You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force.  You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright.  Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+  Conveying under any other circumstances is permitted solely under
+the conditions stated below.  Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+  3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+  No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+  When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+  4. Conveying Verbatim Copies.
+
+  You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+  You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+  5. Conveying Modified Source Versions.
+
+  You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+    a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.
+
+    b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under section
+    7.  This requirement modifies the requirement in section 4 to
+    "keep intact all notices".
+
+    c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy.  This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged.  This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.
+
+    d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.
+
+  A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+  6. Conveying Non-Source Forms.
+
+  You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+    a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.
+
+    b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the
+    Corresponding Source from a network server at no charge.
+
+    c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source.  This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.
+
+    d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge.  You need not require recipients to copy the
+    Corresponding Source along with the object code.  If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source.  Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.
+
+    e) Convey the object code using peer-to-peer transmission, provided
+    you inform other peers where the object code and Corresponding
+    Source of the work are being offered to the general public at no
+    charge under subsection 6d.
+
+  A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+  A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling.  In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage.  For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product.  A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+  "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source.  The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+  If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information.  But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+  The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed.  Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+  Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+  7. Additional Terms.
+
+  "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+  When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+  Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+    a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or
+
+    b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or
+
+    c) Prohibiting misrepresentation of the origin of that material, or
+    requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or
+
+    d) Limiting the use for publicity purposes of names of licensors or
+    authors of the material; or
+
+    e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or
+
+    f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions of
+    it) with contractual assumptions of liability to the recipient, for
+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.
+
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+  If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

c/Makefile

@@ -0,0 +1,59 @@
+# Tools Makefile
+#
+# Copyright (C) 2023 Bruno Raoult ("br")
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+
+SHELL     := /bin/bash
+CC        := gcc
+BEAR      := bear
+
+CFLAGS    += -std=gnu11
+CFLAGS    += -O2
+CFLAGS    += -g
+CFLAGS    += -Wall
+CFLAGS    += -Wextra
+CFLAGS    += -march=native
+CFLAGS    += -Wmissing-declarations
+CFLAGS    += -Wno-unused-result
+# for gprof
+#CFLAGS    += -pg
+# Next one may be useful for valgrind (some invalid instructions)
+#CFLAGS    += -mno-tbm
+
+CPPFLAGS += -DDEBUG_DEBUG		# activate general debug (debug.c)
+CPPFLAGS += -DDEBUG_POOL		# memory pools management
+
+INCDIR    := ./include
+LIBDIR    := ./lib
+OBJDIR    := ./obj
+BRLIBDIR  := ./brlib
+
+LIBNAME   := br_$(shell uname -m)
+#LIB       := lib$(LIBNAME)
+
+
+all: brlib
+
+#export LD_LIBRARY_PATH = $(LIBDIR)
+
+.PHONY: all brlib clean
+
+all: brlib
+
+brlib:
+	$(MAKE) -C $(BRLIBDIR)
+
+bear ccls:
+	@echo building ccls language server compilation database
+	$(MAKE) -C $(BRLIBDIR) ccls
+
+clean:
+	@echo cleaning brlib.
+	@$(MAKE) -C $(BRLIBDIR) clean

c/brlib/Makefile

@@ -0,0 +1,298 @@
+# brlib Makefile - GNU make only
+#
+# Copyright (C) 2021-2023 Bruno Raoult ("br")
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+
+# important to know where exactly is project root dir
+ROOTDIR   := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
+
+SHELL     := /bin/bash
+CC        := gcc
+LD        := ld
+BEAR      := bear
+TOUCH     := touch
+RM        := rm
+MKDIR     := mkdir -p
+RMDIR     := rmdir
+
+SRCDIR    := ./src
+INCDIR    := ./include
+OBJDIR    := ./obj
+LIBDIR    := ./lib
+BINDIR    := ./bin
+DEPDIR    := ./dep
+TESTDIR   := ./test
+
+SRC       := $(wildcard $(SRCDIR)/*.c)                      # brlib sources
+SRC_FN    := $(notdir $(SRC))                               # source basename
+OBJ       := $(addprefix $(OBJDIR)/,$(SRC_FN:.c=.o))
+
+LIB       := br_$(shell uname -m)                           # library name
+SLIB      := $(addsuffix .a, $(LIBDIR)/lib$(LIB))           # static lib
+DLIB      := $(addsuffix .so, $(LIBDIR)/lib$(LIB))          # dynamic lib
+
+DEP_FN    := $(SRC_FN) $(LIBSRC_FN)
+DEP       := $(addprefix $(DEPDIR)/,$(DEP_FN:.c=.d))
+
+TESTSRC   := $(wildcard $(TESTDIR)/*.c)
+TEST_FN   := $(notdir $(TESTSRC))
+BIN       := $(addprefix $(BINDIR)/,$(TEST_FN:.c=))
+
+##################################### emacs projectile/ccls dirs & files
+PRJROOT   := .projectile
+EMACSLSP  := .dir-locals.el
+
+CCLSROOT  := .ccls-root
+CCLSFILE  := .ccls
+CCLSCMDS  := compile_commands.json
+
+##################################### pre-processor flags
+CPPFLAGS  := -I$(INCDIR)
+#CPPFLAGS  += -DDEBUG                                       # global
+#CPPFLAGS  += -DDEBUG_DEBUG_C                               # log() funcs debug
+CPPFLAGS  += -DDEBUG_DEBUG                                  # activate logs funcs
+CPPFLAGS  += -DDEBUG_POOL                                   # mem pools
+
+# remove extraneous spaces (due to spaces before comments)
+CPPFLAGS  := $(strip $(CPPFLAGS))
+
+##################################### compiler flags
+CFLAGS    := -std=gnu11
+CFLAGS    += -O2
+CFLAGS    += -g
+CFLAGS    += -Wall
+CFLAGS    += -Wextra
+CFLAGS    += -march=native
+CFLAGS    += -Wmissing-declarations
+CFLAGS    += -Wno-unused-result
+CFLAGS    += -fPIC
+# for gprof
+#CFLAGS    += -pg
+# Next one may be useful for valgrind (some invalid instructions)
+# CFLAGS   += -mno-tbm
+
+CFLAGS    := $(strip $(CFLAGS))
+
+##################################### archiver/linker/dependency flags
+ARFLAGS   := rcs
+LDFLAGS   := -L$(LIBDIR)
+DEPFLAGS   = -MMD -MP -MF $(DEPDIR)/$*.d
+
+##################################### General targets
+.PHONY: all compile clean cleanall cleanallall
+
+all: libs
+
+compile: objs
+
+test: testbins
+
+clean: cleandep cleanobj cleanlib cleanbin
+
+cleanall: clean cleandepdir cleanobjdir cleanlibdir cleanbindir
+
+cleanallall: cleanall cleanemacs
+
+# setup emacs projectile/ccls
+emacs: emacs-setup
+# update compile-commands.json
+ccls: $(CCLSCMDS)
+
+##################################### cleaning functions
+# rmfiles - deletes a list of files in a directory if they exist.
+# $(1): the directory
+# $(2): the list of files to delete
+# $(3): The string to include in action output - "cleaning X files."
+# see: https://stackoverflow.com/questions/6783243/functions-in-makefiles
+#
+# Don't use wildcard like "$(DIR)/*.o", so we can control mismatches between
+# list and actual files in directory.
+# See rmdir below.
+define rmfiles
+	@#echo "rmfiles=+$(1)+"
+	$(eval $@_EXIST = $(wildcard $(1)))
+	@#echo "existfile=+${$@_EXIST}+"
+	@if [[ -n "${$@_EXIST}" ]]; then         \
+		echo "cleaning $(2) files." ;    \
+		$(RM) ${$@_EXIST} ;              \
+	fi
+endef
+
+# rmdir - deletes a directory if it exists.
+# $(1): the directory
+# $(2): The string to include in action output - "removing X dir."
+#
+# Don't use $(RM) -rf, to control unexpected dep files.
+# See rmfile above.
+define rmdir
+	@#echo "rmdir +$(1)+"
+	$(eval $@_EXIST = $(wildcard $(1)))
+	@#echo "existdir=+${$@_EXIST}+"
+	@if [[ -n "${$@_EXIST}" ]]; then         \
+		echo "removing $(2) dir." ;      \
+		$(RMDIR) ${$@_EXIST} ;           \
+	fi
+endef
+
+##################################### dirs creation
+.PHONY: alldirs
+
+ALLDIRS   := $(DEPDIR) $(OBJDIR) $(LIBDIR) $(BINDIR)
+
+alldirs: $(ALLDIRS)
+
+# Here, we have something like:
+# a: a
+# a will be built if (1) older than a, or (2) does not exist. Here only (2).
+$(ALLDIRS): $@
+	@echo creating $@ directory.
+	@$(MKDIR) $@
+
+##################################### Dependencies files
+.PHONY: cleandep cleandepdir
+
+-include $(wildcard $(DEP))
+
+# Don't use $(DEPDIR)/*.d, to control mismatches between dep and src files.
+# See second rule below.
+cleandep:
+	$(call rmfiles,$(DEP),depend)
+	@#echo cleaning dependency files.
+	@#$(RM) -f $(DEP)
+
+cleandepdir:
+	$(call rmdir,$(DEPDIR),depend)
+	@#[ -d $(DEPDIR) ] && echo cleaning depend files && $(RM) -f $(DEP) || true
+
+##################################### objects
+.PHONY: objs cleanobj cleanobjdir
+
+objs: $(OBJ)
+
+cleanobj:
+	$(call rmfiles,$(OBJ),brlib object)
+
+cleanobjdir:
+	$(call rmdir,$(OBJDIR),brlib objects)
+
+$(OBJDIR)/%.o: $(SRCDIR)/%.c | $(OBJDIR) $(DEPDIR)
+	@echo compiling $< "->" $@.
+	$(CC) -c $(DEPFLAGS) $(CPPFLAGS) $(CFLAGS) $< -o $@
+
+##################################### brlib libraries
+.PHONY: libs cleanlib cleanlibdir
+
+libs: $(DLIB) $(SLIB)
+
+cleanlib:
+	$(call rmfiles,$(DLIB) $(SLIB),library)
+
+cleanlibdir:
+	$(call rmdir,$(LIBDIR),libraries)
+
+#$(DLIB): CFLAGS += -fPIC
+$(DLIB): LDFLAGS += -shared
+$(DLIB): $(OBJ) | $(LIBDIR)
+	@echo "building shared library ($@)."
+	$(CC) $(CFLAGS) $(LDFLAGS) $? -o $@
+
+$(SLIB): $(OBJ) | $(LIBDIR)
+	@echo "building static library ($@)."
+	$(AR) $(ARFLAGS) $@ $? > /dev/null
+
+##################################### tests
+.PHONY: testbins cleanbin cleanbindir
+
+testbins: $(BIN)
+	echo $^
+
+cleanbin:
+	$(call rmfiles,$(TARGET),binary)
+
+cleanbindir:
+	$(call rmdir,$(BINDIR),binaries)
+
+##################################### pre-processed (.i) and assembler (.s) output
+%.i: %.c
+	@echo generating $@
+	@$(CC) -E $(CPPFLAGS) $(CFLAGS) $< -o $@
+
+%.s: %.c
+	@echo generating $@
+	@$(CC) -S -fverbose-asm $(CPPFLAGS) $(CFLAGS) $< -o $@
+
+##################################### Emacs
+.PHONY: emacs-setup cleanemacs
+
+emacs-setup: $(PRJROOT) $(EMACSLSP)
+
+cleanemacs:
+	$(call rmfiles, $(PRJROOT) $(EMACSLSP), Emacs);
+
+$(PRJROOT) $(EMACSLSP):
+	@if [[ $(@) = $(PRJROOT) ]] ;                           \
+	then                                                    \
+		echo "creating Emacs's projectile root file." ; \
+	else                                                    \
+		echo "creating Emacs's ccls root file." ;       \
+	fi
+	@$(TOUCH) $@
+
+##################################### LSP (ccls)
+.PHONY: cleanccls
+
+cleanccls:
+	$(call rmfiles, $(CCLSROOT), ccls);
+
+$(CCLSROOT):
+	echo "creating ccls root file."
+	@$(TOUCH) $@
+
+# generate compile_commands.json.
+# TODO: add includes and Makefile dependencies.
+# also, if cclsfile is newer than sources, no need to clean objects file
+# (and to run bear).
+# maybe run cleanobj cleanlibobj in commands ?
+$(CCLSCMDS): cleanobj $(SRC) | $(CCLSROOT)
+	@echo "Generating ccls compile commands file ($@)."
+	@$(BEAR) -- make compile
+
+#.PHONY: bear
+#bear: cleanobj cleanlibobj Makefile | $(CCLSROOT)
+#    @$(BEAR) -- make compile
+
+##################################### valgrind (mem check)
+.PHONY: memcheck
+
+VALGRIND      := valgrind
+VALGRINDFLAGS := --leak-check=full --show-leak-kinds=all
+VALGRINDFLAGS += --track-origins=yes --sigill-diagnostics=yes
+VALGRINDFLAGS += --quiet --show-error-list=yes
+VALGRINDFLAGS += --log-file=valgrind.out
+# We need to suppress libreadline leaks here. See :
+# https://stackoverflow.com/questions/72840015
+VALGRINDFLAGS += --suppressions=etc/libreadline.supp
+
+memcheck: targets
+	@$(VALGRIND) $(VALGRINDFLAGS) $(BINDIR)/brchess
+
+##################################### Makefile debug
+.PHONY: showflags wft
+
+showflags:
+	@echo CFLAGS: "$(CFLAGS)"
+	@echo CPPFLAGS: $(CPPFLAGS)
+	@echo DEPFLAGS: $(DEPFLAGS)
+	@echo LDFLAGS: $(LDFLAGS)
+
+wtf:
+	@printf "ROOTDIR=+%s+\n\n" "$(ROOTDIR)"
+	@printf "OBJDIR=%s\n\n" "$(OBJDIR)"
+	@printf "OBJ=%s\n\n" "$(OBJ)"

c/brlib/include/bits.h

@@ -0,0 +1,499 @@
+/* bits.h - bits functions.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+#ifndef _BITS_H
+#define _BITS_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <bits/wordsize.h>                        /* defines __WORDSIZE: 32 or 64 */
+
+void bits_implementation(void);
+
+#ifndef __has_builtin
+#define __has_builtin(x) 0
+#endif
+
+/* no plan to support 32bits for now...
+ * #if __WORDSIZE != 64
+ * #error "Only 64 bits word size supported."
+ * #endif
+ */
+
+/* fixed-size types
+ */
+typedef int64_t  s64;
+typedef int32_t  s32;
+typedef int16_t  s16;
+typedef int8_t   s8;
+
+typedef uint64_t u64;
+typedef uint32_t u32;
+typedef uint16_t u16;
+typedef uint8_t  u8;
+
+/* convenience types
+ */
+typedef long long int llong;
+typedef unsigned long long int ullong;
+typedef unsigned long int ulong;
+typedef unsigned int uint;
+typedef unsigned short ushort;
+typedef unsigned char uchar;
+/* char is a special case, as it can be signed or unsigned
+ */
+typedef signed char schar;
+
+/* define common types sizes
+ */
+#define BITS_PER_CHAR 8
+
+#ifndef BITS_PER_SHORT
+#define BITS_PER_SHORT (BITS_PER_CHAR * sizeof (short))
+#endif
+#ifndef BITS_PER_INT
+#define BITS_PER_INT   (BITS_PER_CHAR * sizeof (int))
+#endif
+#ifndef BITS_PER_LONG
+#define BITS_PER_LONG  (BITS_PER_CHAR * sizeof (long))
+#endif
+#ifndef BITS_PER_LLONG
+#define BITS_PER_LLONG (BITS_PER_CHAR * sizeof (long long))
+#endif
+
+/* count set bits:  10101000 -> 3
+ *                  ^ ^ ^
+ */
+static __always_inline int popcount64(u64 n)
+{
+#   if __has_builtin(__builtin_popcountl)
+    return __builtin_popcountl(n);
+
+#   else
+    int count = 0;
+    while (n) {
+        count++;
+        n &= (n - 1);
+    }
+    return count;
+#   endif
+}
+
+static __always_inline int popcount32(u32 n)
+{
+#   if __has_builtin(__builtin_popcount)
+    return __builtin_popcount(n);
+
+#   else
+    int count = 0;
+    while (n) {
+        count++;
+        n &= (n - 1);
+    }
+    return count;
+#   endif
+}
+
+/* count trailing zeroes : 00101000 -> 3
+ *                              ^^^
+ */
+static __always_inline int ctz64(u64 n)
+{
+#   if __has_builtin(__builtin_ctzl)
+    return __builtin_ctzl(n);
+
+#   elif __has_builtin(__builtin_clzl)
+    return __WORDSIZE - (__builtin_clzl(n & -n) + 1);
+
+#   else
+    return popcount64((n & -n) - 1);
+#   endif
+}
+
+static __always_inline int ctz32(u32 n)
+{
+#   if __has_builtin(__builtin_ctz)
+    return __builtin_ctzl(n);
+
+#   elif __has_builtin(__builtin_clz)
+    return __WORDSIZE - (__builtin_clz(n & -n) + 1);
+
+#   else
+    return popcount32((n & -n) - 1);
+#   endif
+}
+
+/* clz - count leading zeroes : 00101000 -> 2
+ *                              ^^
+ */
+static __always_inline int clz64(u64 n)
+{
+#   if __has_builtin(__builtin_clzl)
+    return __builtin_clzl(n);
+
+#   else
+    u64 r, q;
+
+    r = (n > 0xFFFFFFFF) << 5; n >>= r;
+    q = (n > 0xFFFF)     << 4; n >>= q; r |= q;
+    q = (n > 0xFF  )     << 3; n >>= q; r |= q;
+    q = (n > 0xF   )     << 2; n >>= q; r |= q;
+    q = (n > 0x3   )     << 1; n >>= q; r |= q;
+    r |= (n >> 1);
+    return 64 - r - 1;
+#   endif
+}
+
+static __always_inline int clz32(u32 n)
+{
+#   if __has_builtin(__builtin_clz)
+    return __builtin_clz(n);
+
+#   else
+    u32 r, q;
+
+    r = (n > 0xFFFF)     << 4; n >>= r;
+    q = (n > 0xFF  )     << 3; n >>= q; r |= q;
+    q = (n > 0xF   )     << 2; n >>= q; r |= q;
+    q = (n > 0x3   )     << 1; n >>= q; r |= q;
+    r |= (n >> 1);
+    return 32 - r - 1;
+#   endif
+}
+
+/* fls - find last set : 00101000 -> 6
+ *                         ^
+ */
+static __always_inline int fls64(u64 n)
+{
+    if (!n)
+        return 0;
+    return 64 - clz64(n);
+}
+
+static __always_inline int fls32(u32 n)
+{
+    if (!n)
+        return 0;
+    return 32 - clz32(n);
+}
+
+/* find first set :  00101000 -> 4
+ *                       ^
+ */
+static __always_inline uint ffs64(u64 n)
+{
+#   if __has_builtin(__builtin_ffsl)
+    return __builtin_ffsl(n);
+
+#   elif __has_builtin(__builtin_ctzl)
+    if (n == 0)
+        return (0);
+    return __builtin_ctzl(n) + 1;
+
+#   else
+    return popcount64(n ^ ~-n);
+#   endif
+}
+
+static __always_inline uint ffs32(u32 n)
+{
+#   if __has_builtin(__builtin_ffs)
+    return __builtin_ffs(n);
+
+#   elif __has_builtin(__builtin_ctz)
+    if (n == 0)
+        return (0);
+    return __builtin_ctz(n) + 1;
+
+#   else
+    return popcount32(n ^ ~-n);
+#   endif
+}
+
+/* rolXX/rorXX are taken from kernel's <linux/bitops.h> are are:
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+/**
+ * rol64 - rotate a 64-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u64 rol64(u64 word, unsigned int shift)
+{
+        return (word << (shift & 63)) | (word >> ((-shift) & 63));
+}
+
+/**
+ * ror64 - rotate a 64-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u64 ror64(u64 word, unsigned int shift)
+{
+        return (word >> (shift & 63)) | (word << ((-shift) & 63));
+}
+
+/**
+ * rol32 - rotate a 32-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u32 rol32(u32 word, unsigned int shift)
+{
+        return (word << (shift & 31)) | (word >> ((-shift) & 31));
+}
+
+/**
+ * ror32 - rotate a 32-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u32 ror32(u32 word, unsigned int shift)
+{
+        return (word >> (shift & 31)) | (word << ((-shift) & 31));
+}
+
+/**
+ * rol16 - rotate a 16-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u16 rol16(u16 word, unsigned int shift)
+{
+        return (word << (shift & 15)) | (word >> ((-shift) & 15));
+}
+
+/**
+ * ror16 - rotate a 16-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u16 ror16(u16 word, unsigned int shift)
+{
+        return (word >> (shift & 15)) | (word << ((-shift) & 15));
+}
+
+/**
+ * rol8 - rotate an 8-bit value left
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u8 rol8(u8 word, unsigned int shift)
+{
+        return (word << (shift & 7)) | (word >> ((-shift) & 7));
+}
+
+/**
+ * ror8 - rotate an 8-bit value right
+ * @word: value to rotate
+ * @shift: bits to roll
+ */
+static inline u8 ror8(u8 word, unsigned int shift)
+{
+        return (word >> (shift & 7)) | (word << ((-shift) & 7));
+}
+
+/**
+ * __ilog2 - non-constant log of base 2 calculators
+ * - the arch may override these in asm/bitops.h if they can be implemented
+ *   more efficiently than using fls() and fls64()
+ * - the arch is not required to handle n==0 if implementing the fallback
+ */
+static __always_inline __attribute__((const))
+int __ilog2_u64(u64 n)
+{
+        return fls64(n) - 1;
+}
+
+static __always_inline __attribute__((const))
+int __ilog2_u32(u32 n)
+{
+        return fls32(n) - 1;
+}
+
+/**
+ * is_power_of_2() - check if a value is a power of two
+ * @n: the value to check
+ *
+ * Determine whether some value is a power of two, where zero is
+ * *not* considered a power of two.
+ * Return: true if @n is a power of 2, otherwise false.
+ */
+static inline __attribute__((const))
+bool is_power_of_2(unsigned long n)
+{
+        return (n != 0 && ((n & (n - 1)) == 0));
+}
+
+/**
+ * __roundup_pow_of_two() - round up to nearest power of two
+ * @n: value to round up
+ */
+static inline __attribute__((const))
+u64 __roundup_pow_of_two(u64 n)
+{
+        return 1UL << fls64(n - 1);
+}
+
+/**
+ * __rounddown_pow_of_two() - round down to nearest power of two
+ * @n: value to round down
+ */
+static inline __attribute__((const)) u64 __rounddown_pow_of_two(u64 n)
+{
+        return 1UL << (fls64(n) - 1);
+}
+
+/**
+ * ilog2 - log base 2 of 32-bit or a 64-bit unsigned value
+ * @n: parameter
+ *
+ * constant-capable log of base 2 calculation
+ * - this can be used to initialise global variables from constant data, hence
+ * the massive ternary operator construction
+ *
+ * selects the appropriately-sized optimised version depending on sizeof(n)
+ */
+#define ilog2(n)                        \
+(                                       \
+        __builtin_constant_p(n) ?       \
+        ((n) < 2 ? 0 :                  \
+         63 - __builtin_clzll(n)) :     \
+        (sizeof(n) <= 4) ?              \
+        __ilog2_u32(n) :                \
+        __ilog2_u64(n)                  \
+ )
+
+/**
+ * roundup_pow_of_two - round the given value up to nearest power of two
+ * @n: parameter
+ *
+ * round the given value up to the nearest power of two
+ * - the result is undefined when n == 0
+ * - this can be used to initialise global variables from constant data
+ */
+#define roundup_pow_of_two(n)                   \
+(                                               \
+        __builtin_constant_p(n) ? (             \
+                ((n) == 1) ? 1 :                \
+                (1UL << (ilog2((n) - 1) + 1))   \
+                                   ) :          \
+        __roundup_pow_of_two(n)                 \
+ )
+
+/**
+ * rounddown_pow_of_two - round the given value down to nearest power of two
+ * @n: parameter
+ *
+ * round the given value down to the nearest power of two
+ * - the result is undefined when n == 0
+ * - this can be used to initialise global variables from constant data
+ */
+#define rounddown_pow_of_two(n)                 \
+(                                               \
+        __builtin_constant_p(n) ? (             \
+                (1UL << ilog2(n))) :            \
+        __rounddown_pow_of_two(n)               \
+ )
+
+static inline __attribute_const__ int __order_base_2(unsigned long n)
+{
+        return n > 1 ? ilog2(n - 1) + 1 : 0;
+}
+
+/**
+ * order_base_2 - calculate the (rounded up) base 2 order of the argument
+ * @n: parameter
+ *
+ * The first few values calculated by this routine:
+ *  ob2(0) = 0
+ *  ob2(1) = 0
+ *  ob2(2) = 1
+ *  ob2(3) = 2
+ *  ob2(4) = 2
+ *  ob2(5) = 3
+ *  ... and so on.
+ */
+#define order_base_2(n)                         \
+(                                               \
+        __builtin_constant_p(n) ? (             \
+            ((n) == 0 || (n) == 1) ?            \
+            0 :                                 \
+            ilog2((n) - 1) + 1) :               \
+        __order_base_2(n)                       \
+)
+
+static inline __attribute__((const)) int __bits_per(unsigned long n)
+{
+        if (n < 2)
+            return 1;
+        if (is_power_of_2(n))
+            return order_base_2(n) + 1;
+        return order_base_2(n);
+}
+
+/**
+ * bits_per - calculate the number of bits required for the argument
+ * @n: parameter
+ *
+ * This is constant-capable and can be used for compile time
+ * initializations, e.g bitfields.
+ *
+ * The first few values calculated by this routine:
+ * bf(0) = 1
+ * bf(1) = 1
+ * bf(2) = 2
+ * bf(3) = 2
+ * bf(4) = 3
+ * ... and so on.
+ */
+#define bits_per(n)                             \
+(                                               \
+        __builtin_constant_p(n) ? (             \
+            ((n) == 0 || (n) == 1) ?            \
+            1 :                                 \
+            ilog2(n) + 1 :                      \
+            __bits_per(n)                       \
+)
+
+/** bit_for_each - iterate over an u64/u32 bits
+ * @pos:        an int used as current bit
+ * @tmp:        a temp u64/u32 used as temporary storage
+ * @ul:         the u64/u32 to loop over
+ *
+ * Usage:
+ * u64 u=139, _t;     //  u=b10001011
+ * int cur;
+ * bit_for_each64(cur, _t, u) {
+ *     printf("%d\n", cur);
+ * }
+ * This will display the position of each bit set in ul: 1, 2, 4, 8
+ *
+ * I should probably re-think the implementation...
+ */
+#define bit_for_each64(pos, tmp, ul)                                    \
+    for (tmp = ul, pos = ffs64(tmp); tmp; tmp &= (tmp - 1),  pos = ffs64(tmp))
+
+#define bit_for_each32(pos, tmp, ul)                                    \
+    for (tmp = ul, pos = ffs32(tmp); tmp; tmp &= (tmp - 1),  pos = ffs32(tmp))
+
+/** or would it be more useful (counting bits from zero instead of 1) ?
+ */
+#define bit_for_each64_2(pos, tmp, ul)                                  \
+    for (tmp = ul, pos = ctz64(tmp); tmp; tmp ^= 1UL << pos, pos = ctz64(tmp))
+
+#define bit_for_each32_2(pos, tmp, ul)                                  \
+    for (tmp = ul, pos = ctz32(tmp); tmp; tmp ^= 1U << pos, pos = ctz32(tmp))
+
+#endif  /* _BITS_H */

c/brlib/include/br.h

@@ -0,0 +1,224 @@
+/* br.h - misc macros.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ * Some parts are taken from Linux's kernel <linux/kernel.h> and others, and are :
+ * SPDX-License-Identifier: GPL-2.0
+ *
+ * This header contains generic stuff.
+ */
+
+#ifndef _BR_H
+#define _BR_H
+
+#include "struct-group.h"
+
+/* Indirect stringification.  Doing two levels allows the parameter to be a
+ * macro itself.  For example, compile with -DFOO=bar, __stringify(FOO)
+ * converts to "bar".
+ */
+#define __stringify_1(x...)	#x
+#define __stringify(x...)	__stringify_1(x)
+
+/* generate a (maybe) unique id.
+ */
+#define ___PASTE(x, y)      x##y
+#define __PASTE(x, y)       ___PASTE(x, y)
+#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
+
+/* unused/used parameters/functions
+ * https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-unused-function-attribute
+ * https://gcc.gnu.org/onlinedocs/gcc/Common-Type-Attributes.html#index-unused-type-attribute
+ * https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-unused-variable-attribute
+ * https://gcc.gnu.org/onlinedocs/gcc/Label-Attributes.html#index-unused-label-attribute
+ * https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-used-function-attribute
+ * https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-used-variable-attribute
+ */
+#define __unused             __attribute__((__unused__))
+#define __used               __attribute__((__used__))
+
+/* see https://lkml.org/lkml/2018/3/20/845 for explanation of this monster
+ */
+#define __is_constexpr(x) \
+	(sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8)))
+
+/*
+ * min()/max()/clamp() macros must accomplish three things:
+ *
+ * - avoid multiple evaluations of the arguments (so side-effects like
+ *   "x++" happen only once) when non-constant.
+ * - perform strict type-checking (to generate warnings instead of
+ *   nasty runtime surprises). See the "unnecessary" pointer comparison
+ *   in __typecheck().
+ * - retain result as a constant expressions when called with only
+ *   constant expressions (to avoid tripping VLA warnings in stack
+ *   allocation usage).
+ */
+#define __typecheck(x, y) \
+	(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
+
+#define __no_side_effects(x, y) \
+		(__is_constexpr(x) && __is_constexpr(y))
+
+#define __safe_cmp(x, y) \
+		(__typecheck(x, y) && __no_side_effects(x, y))
+
+#define __cmp(x, y, op)	((x) op (y) ? (x) : (y))
+
+#define __cmp_once(x, y, unique_x, unique_y, op) ({	\
+		typeof(x) unique_x = (x);		\
+		typeof(y) unique_y = (y);		\
+		__cmp(unique_x, unique_y, op); })
+
+#define __careful_cmp(x, y, op) \
+	__builtin_choose_expr(__safe_cmp(x, y), \
+		__cmp(x, y, op), \
+		__cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op))
+
+#define __pure   __attribute__((__pure__))
+
+/**
+ * min - return minimum of two values of the same or compatible types
+ * @x: first value
+ * @y: second value
+ */
+#define min(x, y)	__careful_cmp(x, y, <)
+
+/**
+ * max - return maximum of two values of the same or compatible types
+ * @x: first value
+ * @y: second value
+ */
+#define max(x, y)	__careful_cmp(x, y, >)
+
+/**
+ * min3 - return minimum of three values
+ * @x: first value
+ * @y: second value
+ * @z: third value
+ */
+#define min3(x, y, z) min((typeof(x))min(x, y), z)
+
+/**
+ * max3 - return maximum of three values
+ * @x: first value
+ * @y: second value
+ * @z: third value
+ */
+#define max3(x, y, z) max((typeof(x))max(x, y), z)
+
+/**
+ * min_not_zero - return the minimum that is _not_ zero, unless both are zero
+ * @x: value1
+ * @y: value2
+ */
+#define min_not_zero(x, y) ({			\
+	typeof(x) __x = (x);			\
+	typeof(y) __y = (y);			\
+	__x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
+
+/**
+ * clamp - return a value clamped to a given range with strict typechecking
+ * @val: current value
+ * @lo: lowest allowable value
+ * @hi: highest allowable value
+ *
+ * This macro does strict typechecking of @lo/@hi to make sure they are of the
+ * same type as @val.  See the unnecessary pointer comparisons.
+ */
+#define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
+
+/*
+ * ..and if you can't take the strict
+ * types, you can specify one yourself.
+ *
+ * Or not use min/max/clamp at all, of course.
+ */
+
+/**
+ * min_t - return minimum of two values, using the specified type
+ * @type: data type to use
+ * @x: first value
+ * @y: second value
+ */
+#define min_t(type, x, y)	__careful_cmp((type)(x), (type)(y), <)
+
+/**
+ * max_t - return maximum of two values, using the specified type
+ * @type: data type to use
+ * @x: first value
+ * @y: second value
+ */
+#define max_t(type, x, y)	__careful_cmp((type)(x), (type)(y), >)
+
+/**
+ * clamp_t - return a value clamped to a given range using a given type
+ * @type: the type of variable to use
+ * @val: current value
+ * @lo: minimum allowable value
+ * @hi: maximum allowable value
+ *
+ * This macro does no typechecking and uses temporary variables of type
+ * @type to make all the comparisons.
+ */
+#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
+
+/**
+ * clamp_val - return a value clamped to a given range using val's type
+ * @val: current value
+ * @lo: minimum allowable value
+ * @hi: maximum allowable value
+ *
+ * This macro does no typechecking and uses temporary variables of whatever
+ * type the input argument @val is.  This is useful when @val is an unsigned
+ * type and @lo and @hi are literals that will otherwise be assigned a signed
+ * integer type.
+ */
+#define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
+
+/**
+ * swap - swap values of @a and @b
+ * @a: first value
+ * @b: second value
+ */
+#define swap(a, b) \
+	do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
+
+/**
+ * ARRAY_SIZE - get the number of elements in array @arr
+ * @arr: array to be sized
+ */
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+/**
+ * abs - return absolute value of an argument
+ * @x: the value.  If it is unsigned type, it is converted to signed type first.
+ *     char is treated as if it was signed (regardless of whether it really is)
+ *     but the macro's return type is preserved as char.
+ *
+ * Return: an absolute value of x.
+ */
+#define abs(x)	__abs_choose_expr(x, long long,				\
+		__abs_choose_expr(x, long,				\
+		__abs_choose_expr(x, int,				\
+		__abs_choose_expr(x, short,				\
+		__abs_choose_expr(x, char,				\
+		__builtin_choose_expr(					\
+			__builtin_types_compatible_p(typeof(x), char),	\
+			(char)({ signed char __x = (x); __x<0?-__x:__x; }), \
+			((void)0)))))))
+
+#define __abs_choose_expr(x, type, other) __builtin_choose_expr(	\
+	__builtin_types_compatible_p(typeof(x),   signed type) ||	\
+	__builtin_types_compatible_p(typeof(x), unsigned type),		\
+	({ signed type __x = (x); __x < 0 ? -__x : __x; }), other)
+
+
+#endif  /* _BR_H */

c/brlib/include/bug.h

@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BR_BUG_H
+#define _BR_BUG_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include "likely.h"
+#include "debug.h"
+
+/* BUG functions inspired by Linux kernel's <asm/bug.h>
+ */
+
+#define panic() exit(0xff)
+
+/*
+ * Don't use BUG() or BUG_ON() unless there's really no way out; one
+ * example might be detecting data structure corruption in the middle
+ * of an operation that can't be backed out of.  If the (sub)system
+ * can somehow continue operating, perhaps with reduced functionality,
+ * it's probably not BUG-worthy.
+ *
+ * If you're tempted to BUG(), think again:  is completely giving up
+ * really the *only* solution?  There are usually better options, where
+ * users don't need to reboot ASAP and can mostly shut down cleanly.
+ */
+#define BUG() do {                                                                      \
+        fprintf(stderr, "BUG: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
+        panic();                                                                        \
+    } while (0)
+
+#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
+
+/*
+ * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
+ * significant kernel issues that need prompt attention if they should ever
+ * appear at runtime.
+ *
+ * Do not use these macros when checking for invalid external inputs
+ * (e.g. invalid system call arguments, or invalid data coming from
+ * network/devices), and on transient conditions like ENOMEM or EAGAIN.
+ * These macros should be used for recoverable kernel issues only.
+ * For invalid external inputs, transient conditions, etc use
+ * pr_err[_once/_ratelimited]() followed by dump_stack(), if necessary.
+ * Do not include "BUG"/"WARNING" in format strings manually to make these
+ * conditions distinguishable from kernel issues.
+ *
+ * Use the versions with printk format strings to provide better diagnostics.
+ */
+#define __WARN() do {                                                      \
+        fprintf(stderr, "WARNING: failure at %s:%d/%s()!\n", __FILE__, __LINE__, __func__); \
+    } while (0)
+#define __WARN_printf(arg...) do {              \
+        vfprintf(stderr, arg);                  \
+    } while (0)
+
+#define WARN_ON(condition) ({                   \
+            int __ret_warn_on = !!(condition);  \
+            if (unlikely(__ret_warn_on))        \
+		__WARN();                       \
+            unlikely(__ret_warn_on);            \
+        })
+
+#define WARN(condition, format...) ({           \
+            int __ret_warn_on = !!(condition);  \
+            if (unlikely(__ret_warn_on))        \
+		__WARN_printf(format);          \
+            unlikely(__ret_warn_on);            \
+        })
+
+#endif /* _BR_BUG_H */

c/brlib/include/container-of.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* adaptation of Linux kernel's <linux/container_of.h>
+ */
+#ifndef _BR_CONTAINER_OF_H
+#define _BR_CONTAINER_OF_H
+
+/* Are two types/vars the same type (ignoring qualifiers)? */
+#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
+
+/**
+ * typeof_member -
+ */
+#define typeof_member(T, m)     typeof(((T*)0)->m)
+
+/**
+ * container_of - cast a member of a structure out to the containing structure
+ * @ptr:        the pointer to the member.
+ * @type:       the type of the container struct this is embedded in.
+ * @member:     the name of the member within the struct.
+ *
+ */
+#define container_of(ptr, type, member) ({                              \
+        void *__mptr = (void *)(ptr);                                   \
+        _Static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
+                      __same_type(*(ptr), void),                        \
+                      "pointer type mismatch in container_of()");       \
+        ((type *)(__mptr - offsetof(type, member))); })
+
+#endif /* BR_CONTAINER_OF_H */

c/brlib/include/debug.h

@@ -0,0 +1,115 @@
+/* debug.h - debug/log management.
+ *
+ * Copyright (C) 2021-2023 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef DEBUG_H
+#define DEBUG_H
+
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <br.h>
+
+#define NANOSEC  1000000000                       /* nano sec in sec */
+#define MILLISEC 1000000                          /* milli sec in sec */
+
+#define _printf __attribute__ ((format (printf, 6, 7)))
+
+#ifdef DEBUG_DEBUG
+
+void debug_init(int level, FILE *stream, bool flush);
+void debug_level_set(int level);
+int debug_level_get(void);
+void debug_stream_set(FILE *stream);
+long long debug_timer_elapsed(void);
+void debug_flush_set(bool flush);
+void _printf debug(int level, bool timestamp,
+                   int indent, const char *src,
+                   int line, const char *fmt, ...);
+
+#else  /* DEBUG_DEBUG */
+
+static inline void debug_init(__unused int level,
+                              __unused FILE *stream,
+                              __unused bool flush) {}
+static inline void debug_level_set(__unused int level) {}
+static inline int debug_level_get(void) {return 0;}
+static inline void debug_stream_set(__unused FILE *stream) {}
+static inline long long debug_timer_elapsed(void) {return 0LL;}
+static inline void debug_flush_set(__unused bool level) {}
+static inline void _printf debug(__unused int level, __unused bool timestamp,
+                                 __unused int indent, __unused const char *src,
+                                 __unused int line, __unused const char *fmt, ...) {}
+
+#endif  /* DEBUG_DEBUG */
+
+#undef _printf
+
+/**
+ * log - simple log (no function name, no indent, no timestamp)
+ * @level:      log level
+ * @fmt:        printf format string
+ * @args:       subsequent arguments to printf
+ */
+#define log(level, fmt, args...) \
+    debug((level), false, 0, NULL, 0, fmt, ##args)
+
+/**
+ * log_i - log with indent (no function name, no timestamp)
+ * @level:      log level
+ * @fmt:        printf format string
+ * @args:       subsequent arguments to printf
+ *
+ * Output example:
+ * >>>>val=2
+ */
+#define log_i(level, fmt, args...) \
+    debug((level), false, (level), NULL, 0, fmt, ##args)
+
+/**
+ * log_f - log with function name (no indent name, no timestamp)
+ * @level:      log level
+ * @fmt:        printf format string
+ * @args:       subsequent arguments to printf
+ *
+ * Output example:
+ * [function] val=2
+ */
+#define log_f(level, fmt, args...) \
+    debug((level), false, 0, __func__, 0, fmt, ##args)
+
+/**
+ * log_if - log with function name and line number (no indent name, no timestamp)
+ * @level:      log level
+ * @fmt:        printf format string
+ * @args:       subsequent arguments to printf
+ *
+ * Output example:
+ * >>>> [function:15] val=2
+ */
+#define log_if(level, fmt, args...) \
+    debug((level), false, (level), __func__, __LINE__, fmt, ##args)
+
+/**
+ * log_it - log with function name, line number, indent, and timestamp
+ * @level:      log level
+ * @fmt:        printf format string
+ * @args:       subsequent arguments to printf
+ *
+ * Output example:
+ * >>>> [function:15] val=2
+ */
+#define log_it(level, fmt, args...) \
+    debug((level), true, (level), __func__, __LINE__, fmt, ##args)
+
+#endif /* DEBUG_H */

c/brlib/include/hash.h

@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _BR_HASH_H
+#define _BR_HASH_H
+/* adaptation of Linux kernel's <linux/hash.h> and <linux/stringhash.h>
+ */
+
+/* Fast hashing routine for ints,  longs and pointers.
+   (C) 2002 Nadia Yvette Chambers, IBM */
+
+#include <asm/bitsperlong.h>
+#include "bits.h"
+#include "br.h"
+
+/*
+ * The "GOLDEN_RATIO_PRIME" is used in ifs/btrfs/brtfs_inode.h and
+ * fs/inode.c.  It's not actually prime any more (the previous primes
+ * were actively bad for hashing), but the name remains.
+ */
+#if __BITS_PER_LONG == 32
+#define GOLDEN_RATIO_PRIME GOLDEN_RATIO_32
+#define hash_long(val, bits) hash_32(val, bits)
+#elif __BITS_PER_LONG == 64
+#define hash_long(val, bits) hash_64(val, bits)
+#define GOLDEN_RATIO_PRIME GOLDEN_RATIO_64
+#else
+#error Wordsize not 32 or 64
+#endif
+
+/*
+ * This hash multiplies the input by a large odd number and takes the
+ * high bits.  Since multiplication propagates changes to the most
+ * significant end only, it is essential that the high bits of the
+ * product be used for the hash value.
+ *
+ * Chuck Lever verified the effectiveness of this technique:
+ * http://www.citi.umich.edu/techreports/reports/citi-tr-00-1.pdf
+ *
+ * Although a random odd number will do, it turns out that the golden
+ * ratio phi = (sqrt(5)-1)/2, or its negative, has particularly nice
+ * properties.  (See Knuth vol 3, section 6.4, exercise 9.)
+ *
+ * These are the negative, (1 - phi) = phi**2 = (3 - sqrt(5))/2,
+ * which is very slightly easier to multiply by and makes no
+ * difference to the hash distribution.
+ */
+#define GOLDEN_RATIO_32 0x61C88647
+#define GOLDEN_RATIO_64 0x61C8864680B583EBull
+
+/*
+ * The _generic versions exist only so lib/test_hash.c can compare
+ * the arch-optimized versions with the generic.
+ *
+ * Note that if you change these, any <asm/hash.h> that aren't updated
+ * to match need to have their HAVE_ARCH_* define values updated so the
+ * self-test will not false-positive.
+ */
+#ifndef HAVE_ARCH__HASH_32
+#define __hash_32 __hash_32_generic
+#endif
+static inline u32 __hash_32_generic(u32 val)
+{
+	return val * GOLDEN_RATIO_32;
+}
+
+static inline u32 hash_32(u32 val, unsigned int bits)
+{
+	/* High bits are more random, so use them. */
+	return __hash_32(val) >> (32 - bits);
+}
+
+#ifndef HAVE_ARCH_HASH_64
+#define hash_64 hash_64_generic
+#endif
+static __always_inline u32 hash_64_generic(u64 val, unsigned int bits)
+{
+#if __BITS_PER_LONG == 64
+	/* 64x64-bit multiply is efficient on all 64-bit processors */
+	return val * GOLDEN_RATIO_64 >> (64 - bits);
+#else
+	/* Hash 64 bits using only 32x32-bit multiply. */
+	return hash_32((u32)val ^ __hash_32(val >> 32), bits);
+#endif
+}
+
+static inline u32 hash_ptr(const void *ptr, unsigned int bits)
+{
+	return hash_long((unsigned long)ptr, bits);
+}
+
+/* This really should be called fold32_ptr; it does no hashing to speak of. */
+static inline u32 hash32_ptr(const void *ptr)
+{
+	unsigned long val = (unsigned long)ptr;
+
+#if __BITS_PER_LONG == 64
+	val ^= (val >> 32);
+#endif
+	return (u32)val;
+}
+
+/*
+ * Routines for hashing strings of bytes to a 32-bit hash value.
+ *
+ * These hash functions are NOT GUARANTEED STABLE between kernel
+ * versions, architectures, or even repeated boots of the same kernel.
+ * (E.g. they may depend on boot-time hardware detection or be
+ * deliberately randomized.)
+ *
+ * They are also not intended to be secure against collisions caused by
+ * malicious inputs; much slower hash functions are required for that.
+ *
+ * They are optimized for pathname components, meaning short strings.
+ * Even if a majority of files have longer names, the dynamic profile of
+ * pathname components skews short due to short directory names.
+ * (E.g. /usr/lib/libsesquipedalianism.so.3.141.)
+ */
+
+/*
+ * Version 1: one byte at a time.  Example of use:
+ *
+ * unsigned long hash = init_name_hash;
+ * while (*p)
+ *	hash = partial_name_hash(tolower(*p++), hash);
+ * hash = end_name_hash(hash);
+ *
+ * Although this is designed for bytes, fs/hfsplus/unicode.c
+ * abuses it to hash 16-bit values.
+ */
+
+/* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
+#define init_name_hash(salt)		(unsigned long)(salt)
+
+/* partial hash update function. Assume roughly 4 bits per character */
+static inline unsigned long
+partial_name_hash(unsigned long c, unsigned long prevhash)
+{
+	return (prevhash + (c << 4) + (c >> 4)) * 11;
+}
+
+/*
+ * Finally: cut down the number of bits to a int value (and try to avoid
+ * losing bits).  This also has the property (wanted by the dcache)
+ * that the msbits make a good hash table index.
+ */
+static inline unsigned int end_name_hash(unsigned long hash)
+{
+	return hash_long(hash, 32);
+}
+
+/*
+ * Version 2: One word (32 or 64 bits) at a time.
+ * If CONFIG_DCACHE_WORD_ACCESS is defined (meaning <asm/word-at-a-time.h>
+ * exists, which describes major Linux platforms like x86 and ARM), then
+ * this computes a different hash function much faster.
+ *
+ * If not set, this falls back to a wrapper around the preceding.
+ */
+extern unsigned int __pure hash_string(const void *salt, const char *, unsigned int);
+
+/*
+ * A hash_len is a u64 with the hash of a string in the low
+ * half and the length in the high half.
+ */
+#define hashlen_hash(hashlen) ((u32)(hashlen))
+#define hashlen_len(hashlen)  ((u32)((hashlen) >> 32))
+#define hashlen_create(hash, len) ((u64)(len)<<32 | (u32)(hash))
+
+/* Return the "hash_len" (hash and length) of a null-terminated string */
+extern u64 __pure hashlen_string(const void *salt, const char *name);
+
+#endif /* _BR_HASH_H */

c/brlib/include/hashtable.h

@@ -0,0 +1,202 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* adaptation of Linux kernel's <linux/hashtable.h>
+ */
+
+
+/*
+ * Statically sized hash table implementation
+ * (C) 2012  Sasha Levin <levinsasha928@gmail.com>
+ */
+
+#ifndef _LINUX_HASHTABLE_H
+#define _LINUX_HASHTABLE_H
+
+#include "list.h"
+#include "hash.h"
+//#include <linux/rculist.h>
+
+#define DEFINE_HASHTABLE(name, bits)						\
+	struct hlist_head name[1 << (bits)] =					\
+			{ [0 ... ((1 << (bits)) - 1)] = HLIST_HEAD_INIT }
+
+#define DEFINE_READ_MOSTLY_HASHTABLE(name, bits)				\
+	struct hlist_head name[1 << (bits)] __read_mostly =			\
+			{ [0 ... ((1 << (bits)) - 1)] = HLIST_HEAD_INIT }
+
+#define DECLARE_HASHTABLE(name, bits)                                   	\
+	struct hlist_head name[1 << (bits)]
+
+#define HASH_SIZE(name) (ARRAY_SIZE(name))
+#define HASH_BITS(name) ilog2(HASH_SIZE(name))
+
+/* Use hash_32 when possible to allow for fast 32bit hashing in 64bit kernels. */
+#define hash_min(val, bits)							\
+	(sizeof(val) <= 4 ? hash_32(val, bits) : hash_long(val, bits))
+
+static inline void __hash_init(struct hlist_head *ht, unsigned int sz)
+{
+	unsigned int i;
+
+	for (i = 0; i < sz; i++)
+		INIT_HLIST_HEAD(&ht[i]);
+}
+
+/**
+ * hash_init - initialize a hash table
+ * @hashtable: hashtable to be initialized
+ *
+ * Calculates the size of the hashtable from the given parameter, otherwise
+ * same as hash_init_size.
+ *
+ * This has to be a macro since HASH_BITS() will not work on pointers since
+ * it calculates the size during preprocessing.
+ */
+#define hash_init(hashtable) __hash_init(hashtable, HASH_SIZE(hashtable))
+
+/**
+ * hash_add - add an object to a hashtable
+ * @hashtable: hashtable to add to
+ * @node: the &struct hlist_node of the object to be added
+ * @key: the key of the object to be added
+ */
+#define hash_add(hashtable, node, key)						\
+	hlist_add_head(node, &hashtable[hash_min(key, HASH_BITS(hashtable))])
+
+/**
+ * hash_add_rcu - add an object to a rcu enabled hashtable
+ * @hashtable: hashtable to add to
+ * @node: the &struct hlist_node of the object to be added
+ * @key: the key of the object to be added
+ */
+#define hash_add_rcu(hashtable, node, key)					\
+	hlist_add_head_rcu(node, &hashtable[hash_min(key, HASH_BITS(hashtable))])
+
+/**
+ * hash_hashed - check whether an object is in any hashtable
+ * @node: the &struct hlist_node of the object to be checked
+ */
+static inline bool hash_hashed(struct hlist_node *node)
+{
+	return !hlist_unhashed(node);
+}
+
+static inline bool __hash_empty(struct hlist_head *ht, unsigned int sz)
+{
+	unsigned int i;
+
+	for (i = 0; i < sz; i++)
+		if (!hlist_empty(&ht[i]))
+			return false;
+
+	return true;
+}
+
+/**
+ * hash_empty - check whether a hashtable is empty
+ * @hashtable: hashtable to check
+ *
+ * This has to be a macro since HASH_BITS() will not work on pointers since
+ * it calculates the size during preprocessing.
+ */
+#define hash_empty(hashtable) __hash_empty(hashtable, HASH_SIZE(hashtable))
+
+/**
+ * hash_del - remove an object from a hashtable
+ * @node: &struct hlist_node of the object to remove
+ */
+static inline void hash_del(struct hlist_node *node)
+{
+	hlist_del_init(node);
+}
+
+/**
+ * hash_for_each - iterate over a hashtable
+ * @name: hashtable to iterate
+ * @bkt: integer to use as bucket loop cursor
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ */
+#define hash_for_each(name, bkt, obj, member)				\
+	for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\
+			(bkt)++)\
+		hlist_for_each_entry(obj, &name[bkt], member)
+
+/**
+ * hash_for_each_rcu - iterate over a rcu enabled hashtable
+ * @name: hashtable to iterate
+ * @bkt: integer to use as bucket loop cursor
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ */
+#define hash_for_each_rcu(name, bkt, obj, member)			\
+	for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\
+			(bkt)++)\
+		hlist_for_each_entry_rcu(obj, &name[bkt], member)
+
+/**
+ * hash_for_each_safe - iterate over a hashtable safe against removal of
+ * hash entry
+ * @name: hashtable to iterate
+ * @bkt: integer to use as bucket loop cursor
+ * @tmp: a &struct hlist_node used for temporary storage
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ */
+#define hash_for_each_safe(name, bkt, tmp, obj, member)			\
+	for ((bkt) = 0, obj = NULL; obj == NULL && (bkt) < HASH_SIZE(name);\
+			(bkt)++)\
+		hlist_for_each_entry_safe(obj, tmp, &name[bkt], member)
+
+/**
+ * hash_for_each_possible - iterate over all possible objects hashing to the
+ * same bucket
+ * @name: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ * @key: the key of the objects to iterate over
+ */
+#define hash_for_each_possible(name, obj, member, key)			\
+	hlist_for_each_entry(obj, &name[hash_min(key, HASH_BITS(name))], member)
+
+/**
+ * hash_for_each_possible_rcu - iterate over all possible objects hashing to the
+ * same bucket in an rcu enabled hashtable
+ * @name: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ * @key: the key of the objects to iterate over
+ */
+#define hash_for_each_possible_rcu(name, obj, member, key, cond...)	\
+	hlist_for_each_entry_rcu(obj, &name[hash_min(key, HASH_BITS(name))],\
+		member, ## cond)
+
+/**
+ * hash_for_each_possible_rcu_notrace - iterate over all possible objects hashing
+ * to the same bucket in an rcu enabled hashtable in a rcu enabled hashtable
+ * @name: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ * @key: the key of the objects to iterate over
+ *
+ * This is the same as hash_for_each_possible_rcu() except that it does
+ * not do any RCU debugging or tracing.
+ */
+#define hash_for_each_possible_rcu_notrace(name, obj, member, key) \
+	hlist_for_each_entry_rcu_notrace(obj, \
+		&name[hash_min(key, HASH_BITS(name))], member)
+
+/**
+ * hash_for_each_possible_safe - iterate over all possible objects hashing to the
+ * same bucket safe against removals
+ * @name: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @tmp: a &struct hlist_node used for temporary storage
+ * @member: the name of the hlist_node within the struct
+ * @key: the key of the objects to iterate over
+ */
+#define hash_for_each_possible_safe(name, obj, tmp, member, key)	\
+	hlist_for_each_entry_safe(obj, tmp,\
+		&name[hash_min(key, HASH_BITS(name))], member)
+
+
+#endif

c/brlib/include/likely.h

@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*  taken from Kernel's <linux/compiler.h
+ */
+#ifndef __LIKELY_H
+#define __LIKELY_H
+
+/* See https://kernelnewbies.org/FAQ/LikelyUnlikely
+ *
+ * In 2 words:
+ * "You should use it [likely() and unlikely()] only in cases when the likeliest
+ *  branch is very very very likely, or when the unlikeliest branch is very very
+ *  very unlikely."
+ */
+# define likely(x)      __builtin_expect(!!(x), 1)
+# define unlikely(x)    __builtin_expect(!!(x), 0)
+
+#endif /* __LIKELY_H */

c/brlib/include/list.h

@@ -0,0 +1,992 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* adaptation of kernel's <linux/list.h>
+ *
+ */
+
+#ifndef __BR_LIST_H
+#define __BR_LIST_H
+
+#include <stddef.h>
+#include <stdbool.h>
+#include "rwonce.h"
+#include "container-of.h"
+
+/************ originally in <include/linux/types.h> */
+struct list_head {
+    struct list_head *next, *prev;
+};
+struct hlist_head {
+    struct hlist_node *first;
+};
+
+struct hlist_node {
+    struct hlist_node *next, **pprev;
+};
+
+/************ originally in <include/linux/poison.h> */
+# define POISON_POINTER_DELTA 0
+/* These are non-NULL pointers that will result in page faults
+ * under normal circumstances, used to verify that nobody uses
+ * non-initialized list entries.
+ */
+#define LIST_POISON1  ((void *) 0x100 + POISON_POINTER_DELTA)
+#define LIST_POISON2  ((void *) 0x200 + POISON_POINTER_DELTA)
+
+/*
+ * Circular doubly linked list implementation.
+ *
+ * Some of the internal functions ("__xxx") are useful when
+ * manipulating whole lists rather than single entries, as
+ * sometimes we already know the next/prev entries and we can
+ * generate better code by using them directly rather than
+ * using the generic single-entry routines.
+ */
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LIST_HEAD(name)                                 \
+    struct list_head name = LIST_HEAD_INIT(name)
+
+/**
+ * INIT_LIST_HEAD - Initialize a list_head structure
+ * @list: list_head structure to be initialized.
+ *
+ * Initializes the list_head to point to itself.  If it is a list header,
+ * the result is an empty list.
+ */
+static inline void INIT_LIST_HEAD(struct list_head *list)
+{
+    WRITE_ONCE(list->next, list);
+    list->prev = list;
+}
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_add(struct list_head *new,
+			      struct list_head *prev,
+			      struct list_head *next)
+{
+    next->prev = new;
+    new->next  = next;
+    new->prev  = prev;
+    WRITE_ONCE(prev->next, new);
+}
+
+/**
+ * list_add - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void list_add(struct list_head *new, struct list_head *head)
+{
+    __list_add(new, head, head->next);
+}
+
+
+/**
+ * list_add_tail - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+static inline void list_add_tail(struct list_head *new, struct list_head *head)
+{
+    __list_add(new, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_del(struct list_head * prev, struct list_head * next)
+{
+    next->prev = prev;
+    WRITE_ONCE(prev->next, next);
+}
+
+/*
+ * Delete a list entry and clear the 'prev' pointer.
+ *
+ * This is a special-purpose list clearing method used in the networking code
+ * for lists allocated as per-cpu, where we don't want to incur the extra
+ * WRITE_ONCE() overhead of a regular list_del_init(). The code that uses this
+ * needs to check the node 'prev' pointer instead of calling list_empty().
+ */
+static inline void __list_del_clearprev(struct list_head *entry)
+{
+    __list_del(entry->prev, entry->next);
+    entry->prev = NULL;
+}
+
+static inline void __list_del_entry(struct list_head *entry)
+{
+    __list_del(entry->prev, entry->next);
+}
+
+/**
+ * list_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ * Note: list_empty() on entry does not return true after this, the entry is
+ * in an undefined state.
+ */
+static inline void list_del(struct list_head *entry)
+{
+    __list_del_entry(entry);
+    entry->next = LIST_POISON1;
+    entry->prev = LIST_POISON2;
+}
+
+/**
+ * list_replace - replace old entry by new one
+ * @old : the element to be replaced
+ * @new : the new element to insert
+ *
+ * If @old was empty, it will be overwritten.
+ */
+static inline void list_replace(struct list_head *old,
+				struct list_head *new)
+{
+    new->next = old->next;
+    new->next->prev = new;
+    new->prev = old->prev;
+    new->prev->next = new;
+}
+
+/**
+ * list_replace_init - replace old entry by new one and initialize the old one
+ * @old : the element to be replaced
+ * @new : the new element to insert
+ *
+ * If @old was empty, it will be overwritten.
+ */
+static inline void list_replace_init(struct list_head *old,
+				     struct list_head *new)
+{
+    list_replace(old, new);
+    INIT_LIST_HEAD(old);
+}
+
+/**
+ * list_swap - replace entry1 with entry2 and re-add entry1 at entry2's position
+ * @entry1: the location to place entry2
+ * @entry2: the location to place entry1
+ */
+static inline void list_swap(struct list_head *entry1,
+			     struct list_head *entry2)
+{
+    struct list_head *pos = entry2->prev;
+
+    list_del(entry2);
+    list_replace(entry1, entry2);
+    if (pos == entry1)
+        pos = entry2;
+    list_add(entry1, pos);
+}
+
+/**
+ * list_del_init - deletes entry from list and reinitialize it.
+ * @entry: the element to delete from the list.
+ */
+static inline void list_del_init(struct list_head *entry)
+{
+    __list_del_entry(entry);
+    INIT_LIST_HEAD(entry);
+}
+
+/**
+ * list_move - delete from one list and add as another's head
+ * @list: the entry to move
+ * @head: the head that will precede our entry
+ */
+static inline void list_move(struct list_head *list, struct list_head *head)
+{
+    __list_del_entry(list);
+    list_add(list, head);
+}
+
+/**
+ * list_move_tail - delete from one list and add as another's tail
+ * @list: the entry to move
+ * @head: the head that will follow our entry
+ */
+static inline void list_move_tail(struct list_head *list,
+				  struct list_head *head)
+{
+    __list_del_entry(list);
+    list_add_tail(list, head);
+}
+
+/**
+ * list_bulk_move_tail - move a subsection of a list to its tail
+ * @head: the head that will follow our entry
+ * @first: first entry to move
+ * @last: last entry to move, can be the same as first
+ *
+ * Move all entries between @first and including @last before @head.
+ * All three entries must belong to the same linked list.
+ */
+static inline void list_bulk_move_tail(struct list_head *head,
+				       struct list_head *first,
+				       struct list_head *last)
+{
+    first->prev->next = last->next;
+    last->next->prev = first->prev;
+
+    head->prev->next = first;
+    first->prev = head->prev;
+
+    last->next = head;
+    head->prev = last;
+}
+
+/**
+ * list_is_first -- tests whether @list is the first entry in list @head
+ * @list: the entry to test
+ * @head: the head of the list
+ */
+static inline int list_is_first(const struct list_head *list,
+                                const struct list_head *head)
+{
+    return list->prev == head;
+}
+
+/**
+ * list_is_last - tests whether @list is the last entry in list @head
+ * @list: the entry to test
+ * @head: the head of the list
+ */
+static inline int list_is_last(const struct list_head *list,
+                               const struct list_head *head)
+{
+    return list->next == head;
+}
+
+/**
+ * list_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+static inline int list_empty(const struct list_head *head)
+{
+    return READ_ONCE(head->next) == head;
+}
+
+/**
+ * list_rotate_left - rotate the list to the left
+ * @head: the head of the list
+ */
+static inline void list_rotate_left(struct list_head *head)
+{
+    struct list_head *first;
+
+    if (!list_empty(head)) {
+        first = head->next;
+        list_move_tail(first, head);
+    }
+}
+
+/**
+ * list_rotate_to_front() - Rotate list to specific item.
+ * @list: The desired new front of the list.
+ * @head: The head of the list.
+ *
+ * Rotates list so that @list becomes the new front of the list.
+ */
+static inline void list_rotate_to_front(struct list_head *list,
+					struct list_head *head)
+{
+    /*
+     * Deletes the list head from the list denoted by @head and
+     * places it as the tail of @list, this effectively rotates the
+     * list so that @list is at the front.
+     */
+    list_move_tail(head, list);
+}
+
+/**
+ * list_is_singular - tests whether a list has just one entry.
+ * @head: the list to test.
+ */
+static inline int list_is_singular(const struct list_head *head)
+{
+    return !list_empty(head) && (head->next == head->prev);
+}
+
+static inline void __list_cut_position(struct list_head *list,
+                                       struct list_head *head, struct list_head *entry)
+{
+    struct list_head *new_first = entry->next;
+    list->next = head->next;
+    list->next->prev = list;
+    list->prev = entry;
+    entry->next = list;
+    head->next = new_first;
+    new_first->prev = head;
+}
+
+/**
+ * list_cut_position - cut a list into two
+ * @list: a new list to add all removed entries
+ * @head: a list with entries
+ * @entry: an entry within head, could be the head itself
+ *	and if so we won't cut the list
+ *
+ * This helper moves the initial part of @head, up to and
+ * including @entry, from @head to @list. You should
+ * pass on @entry an element you know is on @head. @list
+ * should be an empty list or a list you do not care about
+ * losing its data.
+ *
+ */
+static inline void list_cut_position(struct list_head *list,
+                                     struct list_head *head, struct list_head *entry)
+{
+    if (list_empty(head))
+        return;
+    if (list_is_singular(head) &&
+        (head->next != entry && head != entry))
+        return;
+    if (entry == head)
+        INIT_LIST_HEAD(list);
+    else
+        __list_cut_position(list, head, entry);
+}
+
+/**
+ * list_cut_before - cut a list into two, before given entry
+ * @list: a new list to add all removed entries
+ * @head: a list with entries
+ * @entry: an entry within head, could be the head itself
+ *
+ * This helper moves the initial part of @head, up to but
+ * excluding @entry, from @head to @list.  You should pass
+ * in @entry an element you know is on @head.  @list should
+ * be an empty list or a list you do not care about losing
+ * its data.
+ * If @entry == @head, all entries on @head are moved to
+ * @list.
+ */
+static inline void list_cut_before(struct list_head *list,
+				   struct list_head *head,
+				   struct list_head *entry)
+{
+    if (head->next == entry) {
+        INIT_LIST_HEAD(list);
+        return;
+    }
+    list->next = head->next;
+    list->next->prev = list;
+    list->prev = entry->prev;
+    list->prev->next = list;
+    head->next = entry;
+    entry->prev = head;
+}
+
+static inline void __list_splice(const struct list_head *list,
+				 struct list_head *prev,
+				 struct list_head *next)
+{
+    struct list_head *first = list->next;
+    struct list_head *last = list->prev;
+
+    first->prev = prev;
+    prev->next = first;
+
+    last->next = next;
+    next->prev = last;
+}
+
+/**
+ * list_splice - join two lists, this is designed for stacks
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+static inline void list_splice(const struct list_head *list,
+                               struct list_head *head)
+{
+    if (!list_empty(list))
+        __list_splice(list, head, head->next);
+}
+
+/**
+ * list_splice_tail - join two lists, each list being a queue
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+static inline void list_splice_tail(struct list_head *list,
+                                    struct list_head *head)
+{
+    if (!list_empty(list))
+        __list_splice(list, head->prev, head);
+}
+
+/**
+ * list_splice_init - join two lists and reinitialise the emptied list.
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ *
+ * The list at @list is reinitialised
+ */
+static inline void list_splice_init(struct list_head *list,
+				    struct list_head *head)
+{
+    if (!list_empty(list)) {
+        __list_splice(list, head, head->next);
+        INIT_LIST_HEAD(list);
+    }
+}
+
+/**
+ * list_splice_tail_init - join two lists and reinitialise the emptied list
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ *
+ * Each of the lists is a queue.
+ * The list at @list is reinitialised
+ */
+static inline void list_splice_tail_init(struct list_head *list,
+					 struct list_head *head)
+{
+    if (!list_empty(list)) {
+        __list_splice(list, head->prev, head);
+        INIT_LIST_HEAD(list);
+    }
+}
+
+/**
+ * list_entry - get the struct for this entry
+ * @ptr:	the &struct list_head pointer.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_entry(ptr, type, member)           \
+    container_of(ptr, type, member)
+
+/**
+ * list_first_entry - get the first element from a list
+ * @ptr:	the list head to take the element from.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Note, that list is expected to be not empty.
+ */
+#define list_first_entry(ptr, type, member)     \
+    list_entry((ptr)->next, type, member)
+
+/**
+ * list_last_entry - get the last element from a list
+ * @ptr:	the list head to take the element from.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Note, that list is expected to be not empty.
+ */
+#define list_last_entry(ptr, type, member)      \
+    list_entry((ptr)->prev, type, member)
+
+/**
+ * list_first_entry_or_null - get the first element from a list
+ * @ptr:	the list head to take the element from.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Note that if the list is empty, it returns NULL.
+ */
+#define list_first_entry_or_null(ptr, type, member) ({                  \
+            struct list_head *head__ = (ptr);                           \
+            struct list_head *pos__ = READ_ONCE(head__->next);          \
+            pos__ != head__ ? list_entry(pos__, type, member) : NULL;   \
+        })
+
+/**
+ * list_next_entry - get the next element in list
+ * @pos:	the type * to cursor
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_next_entry(pos, member)                            \
+    list_entry((pos)->member.next, __typeof__(*(pos)), member)
+
+/**
+ * list_prev_entry - get the prev element in list
+ * @pos:	the type * to cursor
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_prev_entry(pos, member)                            \
+    list_entry((pos)->member.prev, __typeof__(*(pos)), member)
+
+/**
+ * list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop cursor.
+ * @head:	the head for your list.
+ */
+#define list_for_each(pos, head)                                \
+    for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/**
+ * list_for_each_continue - continue iteration over a list
+ * @pos:	the &struct list_head to use as a loop cursor.
+ * @head:	the head for your list.
+ *
+ * Continue to iterate over a list, continuing after the current position.
+ */
+#define list_for_each_continue(pos, head)                       \
+    for (pos = pos->next; pos != (head); pos = pos->next)
+
+/**
+ * list_for_each_prev	-	iterate over a list backwards
+ * @pos:	the &struct list_head to use as a loop cursor.
+ * @head:	the head for your list.
+ */
+#define list_for_each_prev(pos, head)                           \
+    for (pos = (head)->prev; pos != (head); pos = pos->prev)
+
+/**
+ * list_for_each_safe - iterate over a list safe against removal of list entry
+ * @pos:	the &struct list_head to use as a loop cursor.
+ * @n:		another &struct list_head to use as temporary storage
+ * @head:	the head for your list.
+ */
+#define list_for_each_safe(pos, n, head)                        \
+    for (pos = (head)->next, n = pos->next; pos != (head);      \
+         pos = n, n = pos->next)
+
+/**
+ * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry
+ * @pos:	the &struct list_head to use as a loop cursor.
+ * @n:		another &struct list_head to use as temporary storage
+ * @head:	the head for your list.
+ */
+#define list_for_each_prev_safe(pos, n, head)   \
+    for (pos = (head)->prev, n = pos->prev;     \
+         pos != (head);                         \
+         pos = n, n = pos->prev)
+
+/**
+ * list_entry_is_head - test if the entry points to the head of the list
+ * @pos:	the type * to cursor
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_entry_is_head(pos, head, member)   \
+    (&pos->member == (head))
+
+/**
+ * list_for_each_entry	-	iterate over list of given type
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_for_each_entry(pos, head, member)                  \
+    for (pos = list_first_entry(head, __typeof__(*pos), member);	\
+         !list_entry_is_head(pos, head, member);                \
+         pos = list_next_entry(pos, member))
+
+/**
+ * list_for_each_entry_reverse - iterate backwards over list of given type.
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_for_each_entry_reverse(pos, head, member)          \
+    for (pos = list_last_entry(head, __typeof__(*pos), member);     \
+         !list_entry_is_head(pos, head, member);                \
+         pos = list_prev_entry(pos, member))
+
+/**
+ * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue()
+ * @pos:	the type * to use as a start point
+ * @head:	the head of the list
+ * @member:	the name of the list_head within the struct.
+ *
+ * Prepares a pos entry for use as a start point in list_for_each_entry_continue().
+ */
+#define list_prepare_entry(pos, head, member)           \
+    ((pos) ? : list_entry(head, __typeof__(*pos), member))
+
+/**
+ * list_for_each_entry_continue - continue iteration over list of given type
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Continue to iterate over list of given type, continuing after
+ * the current position.
+ */
+#define list_for_each_entry_continue(pos, head, member) \
+    for (pos = list_next_entry(pos, member);            \
+         !list_entry_is_head(pos, head, member);        \
+         pos = list_next_entry(pos, member))
+
+/**
+ * list_for_each_entry_continue_reverse - iterate backwards from the given point
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Start to iterate over list of given type backwards, continuing after
+ * the current position.
+ */
+#define list_for_each_entry_continue_reverse(pos, head, member) \
+    for (pos = list_prev_entry(pos, member);			\
+         !list_entry_is_head(pos, head, member);                \
+         pos = list_prev_entry(pos, member))
+
+/**
+ * list_for_each_entry_from - iterate over list of given type from the current point
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Iterate over list of given type, continuing from current position.
+ */
+#define list_for_each_entry_from(pos, head, member)     \
+    for (; !list_entry_is_head(pos, head, member);      \
+         pos = list_next_entry(pos, member))
+
+/**
+ * list_for_each_entry_from_reverse - iterate backwards over list of given type
+ *                                    from the current point
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Iterate backwards over list of given type, continuing from current position.
+ */
+#define list_for_each_entry_from_reverse(pos, head, member)     \
+    for (; !list_entry_is_head(pos, head, member);              \
+         pos = list_prev_entry(pos, member))
+
+/**
+ * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
+ * @pos:	the type * to use as a loop cursor.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ */
+#define list_for_each_entry_safe(pos, n, head, member)          \
+    for (pos = list_first_entry(head, __typeof__(*pos), member),	\
+             n = list_next_entry(pos, member);			\
+         !list_entry_is_head(pos, head, member);                \
+         pos = n, n = list_next_entry(n, member))
+
+/**
+ * list_for_each_entry_safe_continue - continue list iteration safe against removal
+ * @pos:	the type * to use as a loop cursor.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Iterate over list of given type, continuing after current point,
+ * safe against removal of list entry.
+ */
+#define list_for_each_entry_safe_continue(pos, n, head, member) \
+    for (pos = list_next_entry(pos, member),                    \
+             n = list_next_entry(pos, member);                  \
+         !list_entry_is_head(pos, head, member);                \
+         pos = n, n = list_next_entry(n, member))
+
+/**
+ * list_for_each_entry_safe_from - iterate over list from current point safe against removal
+ * @pos:	the type * to use as a loop cursor.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Iterate over list of given type from current point, safe against
+ * removal of list entry.
+ */
+#define list_for_each_entry_safe_from(pos, n, head, member)     \
+    for (n = list_next_entry(pos, member);                      \
+         !list_entry_is_head(pos, head, member);                \
+         pos = n, n = list_next_entry(n, member))
+
+/**
+ * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal
+ * @pos:	the type * to use as a loop cursor.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_head within the struct.
+ *
+ * Iterate backwards over list of given type, safe against removal
+ * of list entry.
+ */
+#define list_for_each_entry_safe_reverse(pos, n, head, member)  \
+    for (pos = list_last_entry(head, __typeof__(*pos), member),     \
+             n = list_prev_entry(pos, member);			\
+         !list_entry_is_head(pos, head, member);                \
+         pos = n, n = list_prev_entry(n, member))
+
+/**
+ * list_safe_reset_next - reset a stale list_for_each_entry_safe loop
+ * @pos:	the loop cursor used in the list_for_each_entry_safe loop
+ * @n:		temporary storage used in list_for_each_entry_safe
+ * @member:	the name of the list_head within the struct.
+ *
+ * list_safe_reset_next is not safe to use in general if the list may be
+ * modified concurrently (eg. the lock is dropped in the loop body). An
+ * exception to this is if the cursor element (pos) is pinned in the list,
+ * and list_safe_reset_next is called after re-taking the lock and before
+ * completing the current iteration of the loop body.
+ */
+#define list_safe_reset_next(pos, n, member)    \
+    n = list_next_entry(pos, member)
+
+/*
+ * Double linked lists with a single pointer list head.
+ * Mostly useful for hash tables where the two pointer list head is
+ * too wasteful.
+ * You lose the ability to access the tail in O(1).
+ */
+
+#define HLIST_HEAD_INIT { .first = NULL }
+#define HLIST_HEAD(name) struct hlist_head name = {  .first = NULL }
+#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
+static inline void INIT_HLIST_NODE(struct hlist_node *h)
+{
+    h->next = NULL;
+    h->pprev = NULL;
+}
+
+/**
+ * hlist_unhashed - Has node been removed from list and reinitialized?
+ * @h: Node to be checked
+ *
+ * Not that not all removal functions will leave a node in unhashed
+ * state.  For example, hlist_nulls_del_init_rcu() does leave the
+ * node in unhashed state, but hlist_nulls_del() does not.
+ */
+static inline int hlist_unhashed(const struct hlist_node *h)
+{
+    return !h->pprev;
+}
+
+/**
+ * hlist_unhashed_lockless - Version of hlist_unhashed for lockless use
+ * @h: Node to be checked
+ *
+ * This variant of hlist_unhashed() must be used in lockless contexts
+ * to avoid potential load-tearing.  The READ_ONCE() is paired with the
+ * various WRITE_ONCE() in hlist helpers that are defined below.
+ */
+static inline int hlist_unhashed_lockless(const struct hlist_node *h)
+{
+    return !READ_ONCE(h->pprev);
+}
+
+/**
+ * hlist_empty - Is the specified hlist_head structure an empty hlist?
+ * @h: Structure to check.
+ */
+static inline int hlist_empty(const struct hlist_head *h)
+{
+    return !READ_ONCE(h->first);
+}
+
+static inline void __hlist_del(struct hlist_node *n)
+{
+    struct hlist_node *next = n->next;
+    struct hlist_node **pprev = n->pprev;
+
+    WRITE_ONCE(*pprev, next);
+    if (next)
+        WRITE_ONCE(next->pprev, pprev);
+}
+
+/**
+ * hlist_del - Delete the specified hlist_node from its list
+ * @n: Node to delete.
+ *
+ * Note that this function leaves the node in hashed state.  Use
+ * hlist_del_init() or similar instead to unhash @n.
+ */
+static inline void hlist_del(struct hlist_node *n)
+{
+    __hlist_del(n);
+    n->next = LIST_POISON1;
+    n->pprev = LIST_POISON2;
+}
+
+/**
+ * hlist_del_init - Delete the specified hlist_node from its list and initialize
+ * @n: Node to delete.
+ *
+ * Note that this function leaves the node in unhashed state.
+ */
+static inline void hlist_del_init(struct hlist_node *n)
+{
+    if (!hlist_unhashed(n)) {
+        __hlist_del(n);
+        INIT_HLIST_NODE(n);
+    }
+}
+
+/**
+ * hlist_add_head - add a new entry at the beginning of the hlist
+ * @n: new entry to be added
+ * @h: hlist head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
+{
+    struct hlist_node *first = h->first;
+    WRITE_ONCE(n->next, first);
+    if (first)
+        WRITE_ONCE(first->pprev, &n->next);
+    WRITE_ONCE(h->first, n);
+    WRITE_ONCE(n->pprev, &h->first);
+}
+
+/**
+ * hlist_add_before - add a new entry before the one specified
+ * @n: new entry to be added
+ * @next: hlist node to add it before, which must be non-NULL
+ */
+static inline void hlist_add_before(struct hlist_node *n,
+				    struct hlist_node *next)
+{
+    WRITE_ONCE(n->pprev, next->pprev);
+    WRITE_ONCE(n->next, next);
+    WRITE_ONCE(next->pprev, &n->next);
+    WRITE_ONCE(*(n->pprev), n);
+}
+
+/**
+ * hlist_add_behind - add a new entry after the one specified
+ * @n: new entry to be added
+ * @prev: hlist node to add it after, which must be non-NULL
+ */
+static inline void hlist_add_behind(struct hlist_node *n,
+				    struct hlist_node *prev)
+{
+    WRITE_ONCE(n->next, prev->next);
+    WRITE_ONCE(prev->next, n);
+    WRITE_ONCE(n->pprev, &prev->next);
+
+    if (n->next)
+        WRITE_ONCE(n->next->pprev, &n->next);
+}
+
+/**
+ * hlist_add_fake - create a fake hlist consisting of a single headless node
+ * @n: Node to make a fake list out of
+ *
+ * This makes @n appear to be its own predecessor on a headless hlist.
+ * The point of this is to allow things like hlist_del() to work correctly
+ * in cases where there is no list.
+ */
+static inline void hlist_add_fake(struct hlist_node *n)
+{
+    n->pprev = &n->next;
+}
+
+/**
+ * hlist_fake: Is this node a fake hlist?
+ * @h: Node to check for being a self-referential fake hlist.
+ */
+static inline bool hlist_fake(struct hlist_node *h)
+{
+    return h->pprev == &h->next;
+}
+
+/**
+ * hlist_is_singular_node - is node the only element of the specified hlist?
+ * @n: Node to check for singularity.
+ * @h: Header for potentially singular list.
+ *
+ * Check whether the node is the only node of the head without
+ * accessing head, thus avoiding unnecessary cache misses.
+ */
+static inline bool
+hlist_is_singular_node(struct hlist_node *n, struct hlist_head *h)
+{
+    return !n->next && n->pprev == &h->first;
+}
+
+/**
+ * hlist_move_list - Move an hlist
+ * @old: hlist_head for old list.
+ * @new: hlist_head for new list.
+ *
+ * Move a list from one list head to another. Fixup the pprev
+ * reference of the first entry if it exists.
+ */
+static inline void hlist_move_list(struct hlist_head *old,
+				   struct hlist_head *new)
+{
+    new->first = old->first;
+    if (new->first)
+        new->first->pprev = &new->first;
+    old->first = NULL;
+}
+
+#define hlist_entry(ptr, type, member) container_of(ptr,type,member)
+
+#define hlist_for_each(pos, head)                       \
+    for (pos = (head)->first; pos ; pos = pos->next)
+
+#define hlist_for_each_safe(pos, n, head)                       \
+    for (pos = (head)->first; pos && ({ n = pos->next; 1; });   \
+         pos = n)
+
+#define hlist_entry_safe(ptr, type, member)                     \
+    ({ __typeof__(ptr) ____ptr = (ptr);                             \
+        ____ptr ? hlist_entry(____ptr, type, member) : NULL;    \
+    })
+
+/**
+ * hlist_for_each_entry	- iterate over list of given type
+ * @pos:	the type * to use as a loop cursor.
+ * @head:	the head for your list.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry(pos, head, member)				\
+    for (pos = hlist_entry_safe((head)->first, __typeof__(*(pos)), member); \
+         pos;                                                           \
+         pos = hlist_entry_safe((pos)->member.next, __typeof__(*(pos)), member))
+
+/**
+ * hlist_for_each_entry_continue - iterate over a hlist continuing after current point
+ * @pos:	the type * to use as a loop cursor.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry_continue(pos, member)			\
+    for (pos = hlist_entry_safe((pos)->member.next, __typeof__(*(pos)), member); \
+         pos;                                                           \
+         pos = hlist_entry_safe((pos)->member.next, __typeof__(*(pos)), member))
+
+/**
+ * hlist_for_each_entry_from - iterate over a hlist continuing from current point
+ * @pos:	the type * to use as a loop cursor.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry_from(pos, member)				\
+    for (; pos;                                                         \
+         pos = hlist_entry_safe((pos)->member.next, __typeof__(*(pos)), member))
+
+/**
+ * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
+ * @pos:	the type * to use as a loop cursor.
+ * @n:		a &struct hlist_node to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry_safe(pos, n, head, member) 		\
+    for (pos = hlist_entry_safe((head)->first, __typeof__(*pos), member);   \
+         pos && ({ n = pos->member.next; 1; });                         \
+         pos = hlist_entry_safe(n, __typeof__(*pos), member))
+
+#endif  /* __BR_LIST_H */

c/brlib/include/pjwhash-inline.h

@@ -0,0 +1,53 @@
+/* pjwhash-inline.h - PJW hash function, inline version.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef _PJWHASH_INLINE_H
+#define _PJWHASH_INLINE_H
+
+#include "bits.h"
+
+#define THREE_QUARTERS ((int) ((BITS_PER_INT * 3) / 4))
+#define ONE_EIGHTH     ((int) (BITS_PER_INT / 8))
+#define HIGH_BITS      ( ~((uint)(~0) >> ONE_EIGHTH ))
+
+#ifndef _pjw_inline
+#define _pjw_inline static inline
+#endif
+
+/**
+ * unsigned int pjwhash - PJW hash function
+ * @key:    the key address.
+ * @length: the length of key.
+ *
+ * This hash was created by Peter Jay Weinberger (AT&T Bell Labs):
+ * https://en.wikipedia.org/wiki/PJW_hash_function
+ *
+ * Return: the PJW hash.
+ */
+_pjw_inline uint pjwhash(const void* key, uint length)
+{
+   uint hash = 0, high;
+   const u8 *k = key;
+
+   for (uint i = 0; i < length; ++k, ++i) {
+       hash = (hash << ONE_EIGHTH) + *k;
+      high = hash & HIGH_BITS;
+      if (high != 0) {
+          hash ^= high >> THREE_QUARTERS;
+          hash &= ~high;
+      }
+   }
+   return hash;
+}
+
+#endif  /* _PJWHASH_INLINE_H */

c/brlib/include/pjwhash.h

@@ -0,0 +1,30 @@
+/* pjwhash.h - PJW hash function, extern version.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ */
+
+#ifndef _PJWHASH_H
+#define _PJWHASH_H
+
+#include "bits.h"
+
+/**
+ * unsigned int pjwhash - PJW hash function
+ * @key:    the key address.
+ * @length: the length of key.
+ *
+ * This hash was created by Peter Jay Weinberger (AT&T Bell Labs):
+ * https://en.wikipedia.org/wiki/PJW_hash_function
+ *
+ * Return: the PJW hash.
+ */
+extern uint  pjwhash (const void* key, uint length);
+
+#endif  /* _PJWHASH_H */

c/brlib/include/plist.h

@@ -0,0 +1,345 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+/* adaptation of kernel's <linux/plist.h>
+ *
+ */
+
+/*
+ * Descending-priority-sorted double-linked list
+ *
+ * (C) 2002-2003 Intel Corp
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>.
+ *
+ * 2001-2005 (c) MontaVista Software, Inc.
+ * Daniel Walker <dwalker@mvista.com>
+ *
+ * (C) 2005 Thomas Gleixner <tglx@linutronix.de>
+ *
+ * Simplifications of the original code by
+ * Oleg Nesterov <oleg@tv-sign.ru>
+ *
+ * Based on simple lists (include/linux/list.h).
+ *
+ * This is a priority-sorted list of nodes; each node has a
+ * priority from INT_MIN (highest) to INT_MAX (lowest).
+ *
+ * Addition is O(K), removal is O(1), change of priority of a node is
+ * O(K) and K is the number of RT priority levels used in the system.
+ * (1 <= K <= 99)
+ *
+ * This list is really a list of lists:
+ *
+ *  - The tier 1 list is the prio_list, different priority nodes.
+ *
+ *  - The tier 2 list is the node_list, serialized nodes.
+ *
+ * Simple ASCII art explanation:
+ *
+ * pl:prio_list (only for plist_node)
+ * nl:node_list
+ *   HEAD|             NODE(S)
+ *       |
+ *       ||------------------------------------|
+ *       ||->|pl|<->|pl|<--------------->|pl|<-|
+ *       |   |10|   |21|   |21|   |21|   |40|   (prio)
+ *       |   |  |   |  |   |  |   |  |   |  |
+ *       |   |  |   |  |   |  |   |  |   |  |
+ * |->|nl|<->|nl|<->|nl|<->|nl|<->|nl|<->|nl|<-|
+ * |-------------------------------------------|
+ *
+ * The nodes on the prio_list list are sorted by priority to simplify
+ * the insertion of new nodes. There are no nodes with duplicate
+ * priorites on the list.
+ *
+ * The nodes on the node_list are ordered by priority and can contain
+ * entries which have the same priority. Those entries are ordered
+ * FIFO
+ *
+ * Addition means: look for the prio_list node in the prio_list
+ * for the priority of the node and insert it before the node_list
+ * entry of the next prio_list node. If it is the first node of
+ * that priority, add it to the prio_list in the right position and
+ * insert it into the serialized node_list list
+ *
+ * Removal means remove it from the node_list and remove it from
+ * the prio_list if the node_list list_head is non empty. In case
+ * of removal from the prio_list it must be checked whether other
+ * entries of the same priority are on the list or not. If there
+ * is another entry of the same priority then this entry has to
+ * replace the removed entry on the prio_list. If the entry which
+ * is removed is the only entry of this priority then a simple
+ * remove from both list is sufficient.
+ *
+ * INT_MIN is the highest priority, 0 is the medium highest, INT_MAX
+ * is lowest priority.
+ *
+ * No locking is done, up to the caller.
+ */
+#ifndef _LINUX_PLIST_H_
+#define _LINUX_PLIST_H_
+
+#include "container-of.h"
+#include "list.h"
+//#include <types.h>
+
+// #include <asm/bug.h>
+
+struct plist_head {
+    struct list_head node_list;
+};
+
+struct plist_node {
+    int			prio;
+    struct list_head	prio_list;
+    struct list_head	node_list;
+};
+
+/**
+ * PLIST_HEAD_INIT - static struct plist_head initializer
+ * @head:	struct plist_head variable name
+ */
+#define PLIST_HEAD_INIT(head)				\
+    {							\
+	.node_list = LIST_HEAD_INIT((head).node_list)	\
+            }
+
+/**
+ * PLIST_HEAD - declare and init plist_head
+ * @head:	name for struct plist_head variable
+ */
+#define PLIST_HEAD(head)                                \
+    struct plist_head head = PLIST_HEAD_INIT(head)
+
+/**
+ * PLIST_NODE_INIT - static struct plist_node initializer
+ * @node:	struct plist_node variable name
+ * @__prio:	initial node priority
+ */
+#define PLIST_NODE_INIT(node, __prio)                           \
+    {                                                           \
+	.prio  = (__prio),                                      \
+            .prio_list = LIST_HEAD_INIT((node).prio_list),	\
+            .node_list = LIST_HEAD_INIT((node).node_list),	\
+            }
+
+/**
+ * plist_head_init - dynamic struct plist_head initializer
+ * @head:	&struct plist_head pointer
+ */
+static inline void
+plist_head_init(struct plist_head *head)
+{
+    INIT_LIST_HEAD(&head->node_list);
+}
+
+/**
+ * plist_node_init - Dynamic struct plist_node initializer
+ * @node:	&struct plist_node pointer
+ * @prio:	initial node priority
+ */
+static inline void plist_node_init(struct plist_node *node, int prio)
+{
+    node->prio = prio;
+    INIT_LIST_HEAD(&node->prio_list);
+    INIT_LIST_HEAD(&node->node_list);
+}
+
+extern void plist_add(struct plist_node *node, struct plist_head *head);
+extern void plist_del(struct plist_node *node, struct plist_head *head);
+
+extern void plist_requeue(struct plist_node *node, struct plist_head *head);
+
+/**
+ * plist_for_each - iterate over the plist
+ * @pos:	the type * to use as a loop counter
+ * @head:	the head for your list
+ */
+#define plist_for_each(pos, head)                               \
+    list_for_each_entry(pos, &(head)->node_list, node_list)
+
+/**
+ * plist_for_each_reverse - iterate backwards over the plist
+ * @pos:	the type * to use as a loop counter
+ * @head:	the head for your list
+ */
+#define plist_for_each_reverse(pos, head)                       \
+    list_for_each_entry_reverse(pos, &(head)->node_list, node_list)
+
+/**
+ * plist_for_each_continue - continue iteration over the plist
+ * @pos:	the type * to use as a loop cursor
+ * @head:	the head for your list
+ *
+ * Continue to iterate over plist, continuing after the current position.
+ */
+#define plist_for_each_continue(pos, head)                      \
+    list_for_each_entry_continue(pos, &(head)->node_list, node_list)
+
+/**
+ * plist_for_each_continue_reverse - continue iteration over the plist
+ * @pos:	the type * to use as a loop cursor
+ * @head:	the head for your list
+ *
+ * Continue to iterate backwards over plist, continuing after the current
+ * position.
+ */
+#define plist_for_each_continue_reverse(pos, head)              \
+    list_for_each_entry_continue_reverse(pos, &(head)->node_list, node_list)
+
+/**
+ * plist_for_each_safe - iterate safely over a plist of given type
+ * @pos:	the type * to use as a loop counter
+ * @n:	another type * to use as temporary storage
+ * @head:	the head for your list
+ *
+ * Iterate over a plist of given type, safe against removal of list entry.
+ */
+#define plist_for_each_safe(pos, n, head)                       \
+    list_for_each_entry_safe(pos, n, &(head)->node_list, node_list)
+
+/**
+ * plist_for_each_safe_reverse - iterate backwards safely over a plist of given type
+ * @pos:	the type * to use as a loop counter
+ * @n:	another type * to use as temporary storage
+ * @head:	the head for your list
+ *
+ * Iterate backwards over a plist of given type, safe against removal of list entry.
+ */
+#define plist_for_each_safe_reverse(pos, n, head)               \
+    list_for_each_entry_safe_reverse(pos, n, &(head)->node_list, node_list)
+
+/**
+ * plist_for_each_entry	- iterate over list of given type
+ * @pos:	the type * to use as a loop counter
+ * @head:	the head for your list
+ * @mem:	the name of the list_head within the struct
+ */
+#define plist_for_each_entry(pos, head, mem)                    \
+    list_for_each_entry(pos, &(head)->node_list, mem.node_list)
+
+/**
+ * plist_for_each_entry_reverse	- iterate backwards over list of given type
+ * @pos:	the type * to use as a loop counter
+ * @head:	the head for your list
+ * @mem:	the name of the list_head within the struct
+ */
+#define plist_for_each_entry_reverse(pos, head, mem)                    \
+    list_for_each_entry_reverse(pos, &(head)->node_list, mem.node_list)
+
+/**
+ * plist_for_each_entry_continue - continue iteration over list of given type
+ * @pos:	the type * to use as a loop cursor
+ * @head:	the head for your list
+ * @m:		the name of the list_head within the struct
+ *
+ * Continue to iterate over list of given type, continuing after
+ * the current position.
+ */
+#define plist_for_each_entry_continue(pos, head, m)                     \
+    list_for_each_entry_continue(pos, &(head)->node_list, m.node_list)
+
+/**
+ * plist_for_each_entry_safe - iterate safely over list of given type
+ * @pos:	the type * to use as a loop counter
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list
+ * @m:		the name of the list_head within the struct
+ *
+ * Iterate over list of given type, safe against removal of list entry.
+ */
+#define plist_for_each_entry_safe(pos, n, head, m)                      \
+    list_for_each_entry_safe(pos, n, &(head)->node_list, m.node_list)
+
+/**
+ * plist_head_empty - return !0 if a plist_head is empty
+ * @head:	&struct plist_head pointer
+ */
+static inline int plist_head_empty(const struct plist_head *head)
+{
+    return list_empty(&head->node_list);
+}
+
+/**
+ * plist_node_empty - return !0 if plist_node is not on a list
+ * @node:	&struct plist_node pointer
+ */
+static inline int plist_node_empty(const struct plist_node *node)
+{
+    return list_empty(&node->node_list);
+}
+
+/* All functions below assume the plist_head is not empty. */
+
+/**
+ * plist_first_entry - get the struct for the first entry
+ * @head:	the &struct plist_head pointer
+ * @type:	the type of the struct this is embedded in
+ * @member:	the name of the list_head within the struct
+ */
+#ifdef CONFIG_DEBUG_PLIST
+# define plist_first_entry(head, type, member)          \
+    ({                                                  \
+	WARN_ON(plist_head_empty(head));                \
+	container_of(plist_first(head), type, member);  \
+    })
+#else
+# define plist_first_entry(head, type, member)          \
+    container_of(plist_first(head), type, member)
+#endif
+
+/**
+ * plist_last_entry - get the struct for the last entry
+ * @head:	the &struct plist_head pointer
+ * @type:	the type of the struct this is embedded in
+ * @member:	the name of the list_head within the struct
+ */
+#ifdef CONFIG_DEBUG_PLIST
+# define plist_last_entry(head, type, member)           \
+    ({                                                  \
+	WARN_ON(plist_head_empty(head));                \
+	container_of(plist_last(head), type, member);   \
+    })
+#else
+# define plist_last_entry(head, type, member)           \
+    container_of(plist_last(head), type, member)
+#endif
+
+/**
+ * plist_next - get the next entry in list
+ * @pos:	the type * to cursor
+ */
+#define plist_next(pos)                         \
+    list_next_entry(pos, node_list)
+
+/**
+ * plist_prev - get the prev entry in list
+ * @pos:	the type * to cursor
+ */
+#define plist_prev(pos)                         \
+    list_prev_entry(pos, node_list)
+
+/**
+ * plist_first - return the first node (and thus, highest priority)
+ * @head:	the &struct plist_head pointer
+ *
+ * Assumes the plist is _not_ empty.
+ */
+static inline struct plist_node *plist_first(const struct plist_head *head)
+{
+    return list_entry(head->node_list.next,
+                      struct plist_node, node_list);
+}
+
+/**
+ * plist_last - return the last node (and thus, lowest priority)
+ * @head:	the &struct plist_head pointer
+ *
+ * Assumes the plist is _not_ empty.
+ */
+static inline struct plist_node *plist_last(const struct plist_head *head)
+{
+    return list_entry(head->node_list.prev,
+                      struct plist_node, node_list);
+}
+
+#endif

c/brlib/include/pool.h

@@ -0,0 +1,90 @@
+/* pool.h - A simple memory pool manager.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef POOL_H
+#define POOL_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include "list.h"
+#include "bits.h"
+
+#define POOL_NAME_LENGTH (16)                     /* max name length including trailing \0 */
+
+typedef struct {
+    struct list_head list_blocks;                 /* list of allocated blocks in pool */
+    char data[];                                  /* objects block */
+} block_t;
+
+typedef struct {
+    char name[POOL_NAME_LENGTH];                  /* pool name */
+    size_t eltsize;                               /* object size */
+    u32 available;                                /* current available elements */
+    u32 allocated;                                /* total objects allocated */
+    u32 growsize;                                 /* number of objects per block allocated */
+    u32 nblocks;                                  /* number of blocks allocated */
+    struct list_head list_available;              /* available nodes */
+    struct list_head list_blocks;                 /* allocated blocks */
+} pool_t;
+
+/**
+ * pool_stats - display some pool statistics
+ * @pool:    the pool address.
+ */
+void pool_stats(pool_t *pool);
+
+/**
+ * pool_create - create a new memory pool
+ * @name:    the name to give to the pool.
+ * @grow:    the number of elements to add when no more available.
+ * @size:    the size of an element in pool.
+ *
+ * The name will be truncated to 16 characters (including the final '\0').
+ *
+ * Return:   The address of the created pool, or NULL if error.
+ */
+pool_t *pool_create(const char *name, u32 grow, size_t size);
+
+/**
+ * pool_get() - Get an element from a pool.
+ * @pool:    The pool address.
+ *
+ * Get an object from the pool.
+ *
+ * Return:   The address of the object, or NULL if error.
+ */
+void *pool_get(pool_t *pool);
+
+/**
+ * pool_add() - Add (free) an element to a pool.
+ * @pool:    The pool address.
+ * @elt:     The address of the object to add to the pool.
+ *
+ * The object will be available for further pool_get().
+ *
+ * Return:   The current number of available elements in pool (including
+ *           @elt).
+ */
+u32 pool_add(pool_t *pool, void *elt);
+
+/**
+ * pool_destroy() - destroy a pool.
+ * @pool:    The pool address.
+ *
+ * Attention: All memory is freed, but no check is done whether all pool
+ * elements have been released. Referencing any pool object after this call
+ * will likely imply some memory corruption.
+ */
+void pool_destroy(pool_t *pool);
+
+#endif

c/brlib/include/rwonce.h

@@ -0,0 +1,128 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/* adaptation of kernel's <asm-generic/rwonce.h>
+ * See https://www.kernel.org/doc/Documentation/memory-barriers.txt
+ */
+/*
+ * Prevent the compiler from merging or refetching reads or writes. The
+ * compiler is also forbidden from reordering successive instances of
+ * READ_ONCE and WRITE_ONCE, but only when the compiler is aware of some
+ * particular ordering. One way to make the compiler aware of ordering is to
+ * put the two invocations of READ_ONCE or WRITE_ONCE in different C
+ * statements.
+ *
+ * These two macros will also work on aggregate data types like structs or
+ * unions.
+ *
+ * Their two major use cases are: (1) Mediating communication between
+ * process-level code and irq/NMI handlers, all running on the same CPU,
+ * and (2) Ensuring that the compiler does not fold, spindle, or otherwise
+ * mutilate accesses that either do not require ordering or that interact
+ * with an explicit memory barrier or atomic instruction that provides the
+ * required ordering.
+ */
+#ifndef __BR_RWONCE_H
+#define __BR_RWONCE_H
+
+/************ originally in <include/linux/compiler_attributes.h> */
+#if __has_attribute(__error__)
+# define __compiletime_error(msg)       __attribute__((__error__(msg)))
+#else
+# define __compiletime_error(msg)
+#endif
+
+/************ originally in <include/linux/compiler_types.h> */
+/*
+ * __unqual_scalar_typeof(x) - Declare an unqualified scalar type, leaving
+ *                             non-scalar types unchanged.
+ */
+/*
+ * Prefer C11 _Generic for better compile-times and simpler code. Note: 'char'
+ * is not type-compatible with 'signed char', and we define a separate case.
+ */
+#define __scalar_type_to_expr_cases(type)                               \
+    unsigned type:  (unsigned type)0,                                   \
+    signed type:    (signed type)0
+
+#define __unqual_scalar_typeof(x)                                       \
+    typeof(_Generic((x),                                                \
+                    char:  (char)0,                                     \
+                    __scalar_type_to_expr_cases(char),                  \
+                    __scalar_type_to_expr_cases(short),                 \
+                    __scalar_type_to_expr_cases(int),                   \
+                    __scalar_type_to_expr_cases(long),                  \
+                    __scalar_type_to_expr_cases(long long),             \
+                    default: (x)))
+
+/* Is this type a native word size -- useful for atomic operations */
+#define __native_word(t) \
+    (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \
+     sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long))
+
+#ifdef __OPTIMIZE__
+# define __compiletime_assert(condition, msg, prefix, suffix)           \
+    do {                                                                \
+        extern void prefix ## suffix(void) __compiletime_error(msg);    \
+        if (!(condition))                                               \
+            prefix ## suffix();                                         \
+    } while (0)
+#else
+# define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0)
+#endif
+
+#define _compiletime_assert(condition, msg, prefix, suffix) \
+    __compiletime_assert(condition, msg, prefix, suffix)
+
+/**
+ * compiletime_assert - break build and emit msg if condition is false
+ * @condition: a compile-time constant condition to check
+ * @msg:       a message to emit if condition is false
+ *
+ * In tradition of POSIX assert, this macro will break the build if the
+ * supplied condition is *false*, emitting the supplied error message if the
+ * compiler has support to do so.
+ */
+#define compiletime_assert(condition, msg)                              \
+    _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
+
+#define compiletime_assert_atomic_type(t)                               \
+    compiletime_assert(__native_word(t),                                \
+                       "Need native word sized stores/loads for atomicity.")
+
+/************ originally in <asm-generic/rwonce.h> */
+/*
+ * Yes, this permits 64-bit accesses on 32-bit architectures. These will
+ * actually be atomic in some cases (namely Armv7 + LPAE), but for others we
+ * rely on the access being split into 2x32-bit accesses for a 32-bit quantity
+ * (e.g. a virtual address) and a strong prevailing wind.
+ */
+#define compiletime_assert_rwonce_type(t)                                  \
+    compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
+                       "Unsupported access size for {READ,WRITE}_ONCE().")
+
+/*
+ * Use __READ_ONCE() instead of READ_ONCE() if you do not require any
+ * atomicity. Note that this may result in tears!
+ */
+#ifndef __READ_ONCE
+#define __READ_ONCE(x)  (*(const volatile __unqual_scalar_typeof(x) *)&(x))
+#endif
+
+#define READ_ONCE(x)                                                    \
+({                                                                      \
+    compiletime_assert_rwonce_type(x);                                  \
+    __READ_ONCE(x);                                                     \
+})
+
+#define __WRITE_ONCE(x, val)                                            \
+do {                                                                    \
+    *(volatile typeof(x) *)&(x) = (val);                                \
+} while (0)
+
+#define WRITE_ONCE(x, val)                                              \
+do {                                                                    \
+    compiletime_assert_rwonce_type(x);                                  \
+    __WRITE_ONCE(x, val);                                               \
+} while (0)
+
+#endif  /* __BR_RWONCE_H */

c/brlib/include/stringhash.h

@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_STRINGHASH_H
+#define __LINUX_STRINGHASH_H
+
+#include <linux/compiler.h>	/* For __pure */
+#include <linux/types.h>	/* For u32, u64 */
+#include <linux/hash.h>
+
+/*
+ * Routines for hashing strings of bytes to a 32-bit hash value.
+ *
+ * These hash functions are NOT GUARANTEED STABLE between kernel
+ * versions, architectures, or even repeated boots of the same kernel.
+ * (E.g. they may depend on boot-time hardware detection or be
+ * deliberately randomized.)
+ *
+ * They are also not intended to be secure against collisions caused by
+ * malicious inputs; much slower hash functions are required for that.
+ *
+ * They are optimized for pathname components, meaning short strings.
+ * Even if a majority of files have longer names, the dynamic profile of
+ * pathname components skews short due to short directory names.
+ * (E.g. /usr/lib/libsesquipedalianism.so.3.141.)
+ */
+
+/*
+ * Version 1: one byte at a time.  Example of use:
+ *
+ * unsigned long hash = init_name_hash;
+ * while (*p)
+ *	hash = partial_name_hash(tolower(*p++), hash);
+ * hash = end_name_hash(hash);
+ *
+ * Although this is designed for bytes, fs/hfsplus/unicode.c
+ * abuses it to hash 16-bit values.
+ */
+
+/* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
+#define init_name_hash(salt)		(unsigned long)(salt)
+
+/* partial hash update function. Assume roughly 4 bits per character */
+static inline unsigned long
+partial_name_hash(unsigned long c, unsigned long prevhash)
+{
+	return (prevhash + (c << 4) + (c >> 4)) * 11;
+}
+
+/*
+ * Finally: cut down the number of bits to a int value (and try to avoid
+ * losing bits).  This also has the property (wanted by the dcache)
+ * that the msbits make a good hash table index.
+ */
+static inline unsigned int end_name_hash(unsigned long hash)
+{
+	return hash_long(hash, 32);
+}
+
+/*
+ * Version 2: One word (32 or 64 bits) at a time.
+ * If CONFIG_DCACHE_WORD_ACCESS is defined (meaning <asm/word-at-a-time.h>
+ * exists, which describes major Linux platforms like x86 and ARM), then
+ * this computes a different hash function much faster.
+ *
+ * If not set, this falls back to a wrapper around the preceding.
+ */
+extern unsigned int __pure full_name_hash(const void *salt, const char *, unsigned int);
+
+/*
+ * A hash_len is a u64 with the hash of a string in the low
+ * half and the length in the high half.
+ */
+#define hashlen_hash(hashlen) ((u32)(hashlen))
+#define hashlen_len(hashlen)  ((u32)((hashlen) >> 32))
+#define hashlen_create(hash, len) ((u64)(len)<<32 | (u32)(hash))
+
+/* Return the "hash_len" (hash and length) of a null-terminated string */
+extern u64 __pure hashlen_string(const void *salt, const char *name);
+
+#endif	/* __LINUX_STRINGHASH_H */

c/brlib/include/struct-group.h

@@ -0,0 +1,105 @@
+/* struct-group.h - mirrored structure macros.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ * Some parts are taken from Linux's kernel <linux/stddef.h> and others, and are :
+ * SPDX-License-Identifier: GPL-2.0
+ *
+ */
+
+#ifndef _STRUCT_GROUP_H
+#define _STRUCT_GROUP_H
+
+/**
+ * __struct_group() - Create a mirrored named and anonyomous struct
+ *
+ * @TAG: The tag name for the named sub-struct (usually empty)
+ * @NAME: The identifier name of the mirrored sub-struct
+ * @ATTRS: Any struct attributes (usually empty)
+ * @MEMBERS: The member declarations for the mirrored structs
+ *
+ * Used to create an anonymous union of two structs with identical layout
+ * and size: one anonymous and one named. The former's members can be used
+ * normally without sub-struct naming, and the latter can be used to
+ * reason about the start, end, and size of the group of struct members.
+ * The named struct can also be explicitly tagged for layer reuse, as well
+ * as both having struct attributes appended.
+ */
+#define __struct_group(TAG, NAME, ATTRS, MEMBERS...) \
+	union { \
+		struct { MEMBERS } ATTRS; \
+		struct TAG { MEMBERS } ATTRS NAME; \
+	}
+
+/**
+ * DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union
+ *
+ * @TYPE: The type of each flexible array element
+ * @NAME: The name of the flexible array member
+ *
+ * In order to have a flexible array member in a union or alone in a
+ * struct, it needs to be wrapped in an anonymous struct with at least 1
+ * named member, but that member can be empty.
+ */
+#define DECLARE_FLEX_ARRAY(TYPE, NAME)	\
+	struct { \
+		struct { } __empty_ ## NAME; \
+		TYPE NAME[]; \
+	}
+
+/**
+ * struct_group() - Wrap a set of declarations in a mirrored struct
+ *
+ * @NAME: The identifier name of the mirrored sub-struct
+ * @MEMBERS: The member declarations for the mirrored structs
+ *
+ * Used to create an anonymous union of two structs with identical
+ * layout and size: one anonymous and one named. The former can be
+ * used normally without sub-struct naming, and the latter can be
+ * used to reason about the start, end, and size of the group of
+ * struct members.
+ */
+#define struct_group(NAME, MEMBERS...)	\
+	__struct_group(/* no tag */, NAME, /* no attrs */, MEMBERS)
+
+/**
+ * struct_group_attr() - Create a struct_group() with trailing attributes
+ *
+ * @NAME: The identifier name of the mirrored sub-struct
+ * @ATTRS: Any struct attributes to apply
+ * @MEMBERS: The member declarations for the mirrored structs
+ *
+ * Used to create an anonymous union of two structs with identical
+ * layout and size: one anonymous and one named. The former can be
+ * used normally without sub-struct naming, and the latter can be
+ * used to reason about the start, end, and size of the group of
+ * struct members. Includes structure attributes argument.
+ */
+#define struct_group_attr(NAME, ATTRS, MEMBERS...) \
+	__struct_group(/* no tag */, NAME, ATTRS, MEMBERS)
+
+/**
+ * struct_group_tagged() - Create a struct_group with a reusable tag
+ *
+ * @TAG: The tag name for the named sub-struct
+ * @NAME: The identifier name of the mirrored sub-struct
+ * @MEMBERS: The member declarations for the mirrored structs
+ *
+ * Used to create an anonymous union of two structs with identical
+ * layout and size: one anonymous and one named. The former can be
+ * used normally without sub-struct naming, and the latter can be
+ * used to reason about the start, end, and size of the group of
+ * struct members. Includes struct tag argument for the named copy,
+ * so the specified layout can be reused later.
+ */
+#define struct_group_tagged(TAG, NAME, MEMBERS...) \
+	__struct_group(TAG, NAME, /* no attrs */, MEMBERS)
+
+#endif  /* _STRUCT_GROUP_H */

c/brlib/src/bits.c

@@ -0,0 +1,91 @@
+/* bits.c - information about bitops implementation.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#include "bits.h"
+#include "debug.h"
+
+/**
+ * bits_implementation - display bitops implementation.
+ *
+ * For basic bitops (popcount, ctz, etc...), print the implementation
+ * (builtin, emulated).
+ */
+void bits_implementation(void)
+{
+    log(0, "bitops implementation: ");
+
+    log(0, "popcount64: ");
+#   if __has_builtin(__builtin_popcountl)
+    log(0, "builtin, ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "popcount32: ");
+#   if __has_builtin(__builtin_popcount)
+    log(0, "builtin, ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "ctz64: ");
+#   if __has_builtin(__builtin_ctzl)
+    log(0, "builtin, ");
+#   elif __has_builtin(__builtin_clzl)
+    log(0, "builtin (clzl), ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "ctz32: ");
+#   if __has_builtin(__builtin_ctz)
+    log(0, "builtin, ");
+#   elif __has_builtin(__builtin_clz)
+    log(0, "builtin (clz), ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "clz64: ");
+#   if __has_builtin(__builtin_clzl)
+    log(0, "builtin, ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "clz32: ");
+#   if __has_builtin(__builtin_clz)
+    log(0, "builtin, ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "ffs64: ");
+#   if __has_builtin(__builtin_ffsl)
+    log(0, "builtin, ");
+#   elif __has_builtin(__builtin_ctzl)
+    log(0, "builtin (ctzl), ");
+#   else
+    log(0, "emulated, ");
+#   endif
+
+    log(0, "ffs32: ");
+#   if __has_builtin(__builtin_ffs)
+    log(0, "builtin, ");
+#   elif __has_builtin(__builtin_ctz)
+    log(0, "builtin (ctzl), ");
+#   else
+    log(0, "emulated, ");
+#   endif
+    log(0, "\n");
+}

c/brlib/src/debug.c

@@ -0,0 +1,126 @@
+/* debug.c - debug/log management
+ *
+ * Copyright (C) 2021-2023 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <time.h>
+
+#ifndef DEBUG_DEBUG
+#define DEBUG_DEBUG
+#endif
+
+#include "debug.h"
+
+static long long timer_start;                     /* in nanosecond */
+static int level = 0;                             /* output log when < level */
+static int flush = false;                         /* force flush after logs */
+static FILE *stream = NULL;                       /* stream to use */
+
+/**
+ * debug_level_set() - set debug level.
+ * @_level: debug level (integer).
+ */
+void debug_level_set(int _level)
+{
+    level = _level;
+#   ifdef DEBUG_DEBUG_C
+    log(0, "debug level set to %u\n", level);
+#   endif
+}
+
+/**
+ * debug_level_get() - get debug level.
+ * @return: current level debug (integer).
+ */
+int debug_level_get(void)
+{
+    return level;
+}
+
+void debug_stream_set(FILE *_stream)
+{
+    stream = _stream;
+#   ifdef DEBUG_DEBUG_C
+    log(0, "stream set to %d\n", stream? fileno(stream): -1);
+#   endif
+}
+
+void debug_flush_set(bool _flush)
+{
+    flush = _flush;
+#   ifdef DEBUG_DEBUG_C
+    log(0, "debug flush %s.\n", flush? "set": "unset");
+#   endif
+}
+
+void debug_init(int _level, FILE *_stream, bool _flush)
+{
+    struct timespec timer;
+
+    debug_stream_set(_stream);
+    debug_level_set(_level);
+    debug_flush_set(_flush);
+    if (!clock_gettime(CLOCK_MONOTONIC, &timer)) {
+        timer_start = timer.tv_sec * NANOSEC + timer.tv_nsec;
+    }
+    else {
+        timer_start = 0;
+    }
+    log(0, "timer started.\n");
+}
+
+long long debug_timer_elapsed(void)
+{
+    struct timespec timer;
+
+    clock_gettime(CLOCK_MONOTONIC, &timer);
+    return (timer.tv_sec * NANOSEC + timer.tv_nsec) - timer_start;
+}
+
+/**
+ * debug() - log function
+ * @lev: log level
+ * @timestamp: boolean, print timestamp if true
+ * @indent: indent level (2 spaces each)
+ * @src: source file/func name (or NULL)
+ * @line: line number
+ */
+void debug(int lev, bool timestamp, int indent, const char *src,
+           int line, const char *fmt, ...)
+{
+    if (!stream || lev > level)
+        return;
+
+    va_list ap;
+
+    if (indent)
+        fprintf(stream, "%*s", 2*(indent-1), "");
+
+    if (timestamp) {
+        long long diff = debug_timer_elapsed();
+        fprintf(stream, "%lld.%03lld ", diff/NANOSEC, (diff/1000000)%1000);
+        fprintf(stream, "%010lld ", diff);
+    }
+
+    if (src) {
+        if (line)
+            fprintf(stream, "[%s:%u] ", src, line);
+        else
+            fprintf(stream, "[%s] ", src);
+    }
+    va_start(ap, fmt);
+    vfprintf(stream, fmt, ap);
+    va_end(ap);
+    if (flush)
+        fflush(stream);
+}

c/brlib/src/hash.c

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*  inspired from kernel's <fs/namei.h>
+ */
+#include "hash.h"
+
+/* Return the hash of a string of known length */
+unsigned int hash_string(const void *salt, const char *name, unsigned int len)
+{
+	unsigned long hash = init_name_hash(salt);
+	while (len--)
+		hash = partial_name_hash((unsigned char)*name++, hash);
+	return end_name_hash(hash);
+}
+
+/* Return the "hash_len" (hash and length) of a null-terminated string */
+u64 hashlen_string(const void *salt, const char *name)
+{
+	unsigned long hash = init_name_hash(salt);
+	unsigned long len = 0, c;
+
+	c = (unsigned char)*name;
+	while (c) {
+		len++;
+		hash = partial_name_hash(c, hash);
+		c = (unsigned char)name[len];
+	}
+	return hashlen_create(end_name_hash(hash), len);
+}

c/brlib/src/pjwhash.c

@@ -0,0 +1,20 @@
+/* pjwhash.c - PJW hash function.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#define _pjw_inline extern
+
+//#include "bits.h"
+//extern unsigned int  pjwhash (const void* key, uint length);
+
+#include "pjwhash.h"
+#include "pjwhash-inline.h"

c/brlib/src/plist.c

@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * adapted from Linux kernel lib/plist.c
+ *
+ * Descending-priority-sorted double-linked list
+ *
+ * (C) 2002-2003 Intel Corp
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>.
+ *
+ * 2001-2005 (c) MontaVista Software, Inc.
+ * Daniel Walker <dwalker@mvista.com>
+ *
+ * (C) 2005 Thomas Gleixner <tglx@linutronix.de>
+ *
+ * Simplifications of the original code by
+ * Oleg Nesterov <oleg@tv-sign.ru>
+ *
+ * Based on simple lists (include/linux/list.h).
+ *
+ * This file contains the add / del functions which are considered to
+ * be too large to inline. See include/linux/plist.h for further
+ * information.
+ */
+
+#include "plist.h"
+#include "bug.h"
+
+#ifdef DEBUG_PLIST
+
+static struct plist_head test_head;
+
+static void plist_check_prev_next(struct list_head *t, struct list_head *p,
+				  struct list_head *n)
+{
+    WARN(n->prev != p || p->next != n,
+         "top: %p, n: %p, p: %p\n"
+         "prev: %p, n: %p, p: %p\n"
+         "next: %p, n: %p, p: %p\n",
+         t, t->next, t->prev,
+         p, p->next, p->prev,
+         n, n->next, n->prev);
+}
+
+static void plist_check_list(struct list_head *top)
+{
+    struct list_head *prev = top, *next = top->next;
+
+    plist_check_prev_next(top, prev, next);
+    while (next != top) {
+        prev = next;
+        next = prev->next;
+        plist_check_prev_next(top, prev, next);
+    }
+}
+
+static void plist_check_head(struct plist_head *head)
+{
+    if (!plist_head_empty(head))
+        plist_check_list(&plist_first(head)->prio_list);
+    plist_check_list(&head->node_list);
+}
+
+#else
+# define plist_check_head(h)	do { } while (0)
+#endif
+
+/**
+ * plist_add - add @node to @head
+ *
+ * @node:	&struct plist_node pointer
+ * @head:	&struct plist_head pointer
+ */
+void plist_add(struct plist_node *node, struct plist_head *head)
+{
+    struct plist_node *first, *iter, *prev = NULL;
+    struct list_head *node_next = &head->node_list;
+
+    plist_check_head(head);
+    WARN_ON(!plist_node_empty(node));
+    WARN_ON(!list_empty(&node->prio_list));
+
+    if (plist_head_empty(head))
+        goto ins_node;
+
+    first = iter = plist_first(head);
+
+    do {
+        if (node->prio < iter->prio) {
+            node_next = &iter->node_list;
+            break;
+        }
+
+        prev = iter;
+        iter = list_entry(iter->prio_list.next,
+                          struct plist_node, prio_list);
+    } while (iter != first);
+
+    if (!prev || prev->prio != node->prio)
+        list_add_tail(&node->prio_list, &iter->prio_list);
+ins_node:
+    list_add_tail(&node->node_list, node_next);
+
+    plist_check_head(head);
+}
+
+/**
+ * plist_del - Remove a @node from plist.
+ *
+ * @node:	&struct plist_node pointer - entry to be removed
+ * @head:	&struct plist_head pointer - list head
+ */
+void plist_del(struct plist_node *node, struct plist_head *head)
+{
+    plist_check_head(head);
+
+    if (!list_empty(&node->prio_list)) {
+        if (node->node_list.next != &head->node_list) {
+            struct plist_node *next;
+
+            next = list_entry(node->node_list.next,
+                              struct plist_node, node_list);
+
+            /* add the next plist_node into prio_list */
+            if (list_empty(&next->prio_list))
+                list_add(&next->prio_list, &node->prio_list);
+        }
+        list_del_init(&node->prio_list);
+    }
+
+    list_del_init(&node->node_list);
+
+    plist_check_head(head);
+}
+
+/**
+ * plist_requeue - Requeue @node at end of same-prio entries.
+ *
+ * This is essentially an optimized plist_del() followed by
+ * plist_add().  It moves an entry already in the plist to
+ * after any other same-priority entries.
+ *
+ * @node:	&struct plist_node pointer - entry to be moved
+ * @head:	&struct plist_head pointer - list head
+ */
+void plist_requeue(struct plist_node *node, struct plist_head *head)
+{
+    struct plist_node *iter;
+    struct list_head *node_next = &head->node_list;
+
+    plist_check_head(head);
+    BUG_ON(plist_head_empty(head));
+    BUG_ON(plist_node_empty(node));
+
+    if (node == plist_last(head))
+        return;
+
+    iter = plist_next(node);
+
+    if (node->prio != iter->prio)
+        return;
+
+    plist_del(node, head);
+
+    plist_for_each_continue(iter, head) {
+        if (node->prio != iter->prio) {
+            node_next = &iter->node_list;
+            break;
+        }
+    }
+    list_add_tail(&node->node_list, node_next);
+
+    plist_check_head(head);
+}

c/brlib/src/pool.c

@@ -0,0 +1,163 @@
+/* pool.c - A simple pool manager.
+ *
+ * Copyright (C) 2021-2022 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#include <stddef.h>
+#include <malloc.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include "list.h"
+#include "pool.h"
+#include "debug.h"
+#include "bits.h"
+
+void pool_stats(pool_t *pool)
+{
+    if (pool) {
+        block_t *block;
+
+        log_f(1, "[%s] pool [%p]: blocks:%u avail:%u alloc:%u grow:%u eltsize:%zu\n",
+              pool->name, (void *)pool, pool->nblocks, pool->available,
+              pool->allocated, pool->growsize, pool->eltsize);
+        log(5, "\tblocks: ");
+        list_for_each_entry(block, &pool->list_blocks, list_blocks) {
+            log(5, "%p ", block);
+        }
+        log(5, "\n");
+    }
+}
+
+pool_t *pool_create(const char *name, u32 growsize, size_t eltsize)
+{
+    pool_t *pool;
+
+#   ifdef DEBUG_POOL
+    log_f(1, "name=[%s] growsize=%u eltsize=%zu\n", name, growsize, eltsize);
+#   endif
+    /* we need at least  sizeof(struct list_head) space in pool elements
+     */
+    if (eltsize < sizeof (struct list_head)) {
+#       ifdef DEBUG_POOL
+        log_f(1, "[%s]: structure size too small (%zu < %zu), adjusting to %zu.\n",
+              name, eltsize, sizeof(struct list_head), sizeof(struct list_head));
+#       endif
+        eltsize = sizeof(struct list_head);
+    }
+    if ((pool = malloc(sizeof (*pool)))) {
+        strncpy(pool->name, name, POOL_NAME_LENGTH - 1);
+        pool->name[POOL_NAME_LENGTH - 1] = 0;
+        pool->growsize = growsize;
+        pool->eltsize = eltsize;
+        pool->available = 0;
+        pool->allocated = 0;
+        pool->nblocks = 0;
+        INIT_LIST_HEAD(&pool->list_available);
+        INIT_LIST_HEAD(&pool->list_blocks);
+    } else {
+        errno = ENOMEM;
+    }
+    return pool;
+}
+
+static u32 _pool_add(pool_t *pool, struct list_head *elt)
+{
+#   ifdef DEBUG_POOL
+    log_f(6, "pool=%p &head=%p elt=%p off1=%zu off2=%zu\n",
+          (void *)pool, (void *)&pool->list_available, (void *)elt,
+          (void *)&pool->list_available - (void *)pool,
+          offsetof(pool_t, list_available));
+#   endif
+
+    list_add(elt, &pool->list_available);
+    return ++pool->available;
+}
+
+u32 pool_add(pool_t *pool, void *elt)
+{
+    return _pool_add(pool, elt);
+}
+
+static struct list_head *_pool_get(pool_t *pool)
+{
+    struct list_head *res = pool->list_available.next;
+    pool->available--;
+    list_del(res);
+    return res;
+}
+
+void *pool_get(pool_t *pool)
+{
+    if (!pool)
+        return NULL;
+    if (!pool->available) {
+        block_t *block = malloc(sizeof(block_t) + pool->eltsize * pool->growsize);
+        if (!block) {
+#           ifdef DEBUG_POOL
+            log_f(1, "[%s]: failed block allocation\n", pool->name);
+#           endif
+            errno = ENOMEM;
+            return NULL;
+        }
+
+        /* maintain list of allocated blocks
+         */
+        list_add(&block->list_blocks, &pool->list_blocks);
+        pool->nblocks++;
+
+#       ifdef DEBUG_POOL
+        log_f(1, "[%s]: growing pool from %u to %u elements. block=%p nblocks=%u\n",
+              pool->name,
+              pool->allocated,
+              pool->allocated + pool->growsize,
+              block,
+              pool->nblocks);
+#       endif
+
+        pool->allocated += pool->growsize;
+        for (u32 i = 0; i < pool->growsize; ++i) {
+            void *cur = block->data + i * pool->eltsize;
+#           ifdef DEBUG_POOL
+            log_f(7, "alloc=%p cur=%p\n", block, cur);
+#           endif
+            _pool_add(pool, (struct list_head *)cur);
+        }
+    }
+    /* this is the effective address of the object (and also the
+     * pool list_head address)
+     */
+    return _pool_get(pool);
+}
+
+void pool_destroy(pool_t *pool)
+{
+    block_t *block, *tmp;
+    if (!pool)
+        return;
+    /* release memory blocks */
+#   ifdef DEBUG_POOL
+    log_f(1, "[%s]: releasing %d blocks and main structure\n", pool->name, pool->nblocks);
+    log(5, "blocks:");
+#   endif
+    list_for_each_entry_safe(block, tmp, &pool->list_blocks, list_blocks) {
+#       ifdef DEBUG_POOL
+        log(5, " %p", block);
+#       endif
+        list_del(&block->list_blocks);
+        free(block);
+    }
+#   ifdef DEBUG_POOL
+    log(5, "\n");
+#   endif
+    free(pool);
+}

c/brlib/test/test/tst-debug.c

@@ -0,0 +1,17 @@
+#include <unistd.h>
+#include "debug.h"
+
+int main()
+{
+    int foo=1;
+    debug_init(5);
+
+    log(0, "log0=%d\n", foo++);
+    log(1, "log1=%d\n", foo++);
+    log(2, "log2=%d\n", foo++);
+    log_i(2, "log_i 2=%d\n", foo++);
+    log_i(5, "log_i 5=%d\n", foo++);
+    log_i(6, "log_i 6=%d\n", foo++);
+    log_it(4, "log_it 4=%d\n", foo++);
+    log_f(1, "log_f 5=%d\n", foo++);
+}

c/brlib/test/tst-pool.c

@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include "bits.h"
+#include "pool.h"
+
+struct d {
+    u16 data1;
+    char c;
+    struct list_head list;
+};
+
+static LIST_HEAD (head);
+
+int main(int ac, char**av)
+{
+    pool_t *pool;
+    int total;
+    int action=0;
+    u16 icur=0;
+    char ccur='z';
+    struct d *elt;
+
+    debug_init(3);
+    log_f(1, "%s: sizeof(d)=%lu sizeof(*d)=%lu off=%lu\n", *av, sizeof(elt),
+          sizeof(*elt), offsetof(struct d, list));
+
+    if ((pool = pool_create("dummy", 3, sizeof(*elt)))) {
+        pool_stats(pool);
+        for (int cur=1; cur<ac; ++cur) {
+            total = atoi(av[cur]);
+            if (action == 0) {                    /* add elt to list */
+                log_f(2, "adding %d elements\n", total);
+                for (int i = 0; i < total; ++i) {
+                    elt = pool_get(pool);
+                    elt->data1 = icur++;
+                    elt->c = ccur--;
+                    list_add(&elt->list, &head);
+                }
+                pool_stats(pool);
+                action = 1;
+            } else {                              /* remove one elt from list */
+                log_f(2, "deleting %d elements\n", total);
+                for (int i = 0; i < total; ++i) {
+                    if (!list_empty(&head)) {
+                        elt = list_last_entry(&head, struct d, list);
+                        printf("elt=[%d, %c]\n", elt->data1, elt->c);
+                        list_del(&elt->list);
+                        pool_add(pool, elt);
+                    }
+                }
+                pool_stats(pool);
+                action = 0;
+            }
+        }
+    }
+    pool_stats(pool);
+    pool_destroy(pool);
+}

c/brlib/todo/asm/unaligned.h

@@ -0,0 +1,155 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_GENERIC_UNALIGNED_H
+#define __ASM_GENERIC_UNALIGNED_H
+
+/*
+ * This is the most generic implementation of unaligned accesses
+ * and should work almost anywhere.
+ */
+#include <linux/unaligned/packed_struct.h>
+#include <asm/byteorder.h>
+
+#define __get_unaligned_t(type, ptr) ({						\
+	const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr);	\
+	__pptr->x;								\
+})
+
+#define __put_unaligned_t(type, val, ptr) do {					\
+	struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr);		\
+	__pptr->x = (val);							\
+} while (0)
+
+#define get_unaligned(ptr)	__get_unaligned_t(typeof(*(ptr)), (ptr))
+#define put_unaligned(val, ptr) __put_unaligned_t(typeof(*(ptr)), (val), (ptr))
+
+static inline u16 get_unaligned_le16(const void *p)
+{
+	return le16_to_cpu(__get_unaligned_t(__le16, p));
+}
+
+static inline u32 get_unaligned_le32(const void *p)
+{
+	return le32_to_cpu(__get_unaligned_t(__le32, p));
+}
+
+static inline u64 get_unaligned_le64(const void *p)
+{
+	return le64_to_cpu(__get_unaligned_t(__le64, p));
+}
+
+static inline void put_unaligned_le16(u16 val, void *p)
+{
+	__put_unaligned_t(__le16, cpu_to_le16(val), p);
+}
+
+static inline void put_unaligned_le32(u32 val, void *p)
+{
+	__put_unaligned_t(__le32, cpu_to_le32(val), p);
+}
+
+static inline void put_unaligned_le64(u64 val, void *p)
+{
+	__put_unaligned_t(__le64, cpu_to_le64(val), p);
+}
+
+static inline u16 get_unaligned_be16(const void *p)
+{
+	return be16_to_cpu(__get_unaligned_t(__be16, p));
+}
+
+static inline u32 get_unaligned_be32(const void *p)
+{
+	return be32_to_cpu(__get_unaligned_t(__be32, p));
+}
+
+static inline u64 get_unaligned_be64(const void *p)
+{
+	return be64_to_cpu(__get_unaligned_t(__be64, p));
+}
+
+static inline void put_unaligned_be16(u16 val, void *p)
+{
+	__put_unaligned_t(__be16, cpu_to_be16(val), p);
+}
+
+static inline void put_unaligned_be32(u32 val, void *p)
+{
+	__put_unaligned_t(__be32, cpu_to_be32(val), p);
+}
+
+static inline void put_unaligned_be64(u64 val, void *p)
+{
+	__put_unaligned_t(__be64, cpu_to_be64(val), p);
+}
+
+static inline u32 __get_unaligned_be24(const u8 *p)
+{
+	return p[0] << 16 | p[1] << 8 | p[2];
+}
+
+static inline u32 get_unaligned_be24(const void *p)
+{
+	return __get_unaligned_be24(p);
+}
+
+static inline u32 __get_unaligned_le24(const u8 *p)
+{
+	return p[0] | p[1] << 8 | p[2] << 16;
+}
+
+static inline u32 get_unaligned_le24(const void *p)
+{
+	return __get_unaligned_le24(p);
+}
+
+static inline void __put_unaligned_be24(const u32 val, u8 *p)
+{
+	*p++ = val >> 16;
+	*p++ = val >> 8;
+	*p++ = val;
+}
+
+static inline void put_unaligned_be24(const u32 val, void *p)
+{
+	__put_unaligned_be24(val, p);
+}
+
+static inline void __put_unaligned_le24(const u32 val, u8 *p)
+{
+	*p++ = val;
+	*p++ = val >> 8;
+	*p++ = val >> 16;
+}
+
+static inline void put_unaligned_le24(const u32 val, void *p)
+{
+	__put_unaligned_le24(val, p);
+}
+
+static inline void __put_unaligned_be48(const u64 val, u8 *p)
+{
+	*p++ = val >> 40;
+	*p++ = val >> 32;
+	*p++ = val >> 24;
+	*p++ = val >> 16;
+	*p++ = val >> 8;
+	*p++ = val;
+}
+
+static inline void put_unaligned_be48(const u64 val, void *p)
+{
+	__put_unaligned_be48(val, p);
+}
+
+static inline u64 __get_unaligned_be48(const u8 *p)
+{
+	return (u64)p[0] << 40 | (u64)p[1] << 32 | (u64)p[2] << 24 |
+		p[3] << 16 | p[4] << 8 | p[5];
+}
+
+static inline u64 get_unaligned_be48(const void *p)
+{
+	return __get_unaligned_be48(p);
+}
+
+#endif /* __ASM_GENERIC_UNALIGNED_H */

c/brlib/todo/circ_buf.c

@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * See Documentation/core-api/circular-buffers.rst for more information.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#define CIRC_BUF(name, type, bits)               \
+    struct s##name {                             \
+        type buf[1 << (bits)];                   \
+        int head;                                \
+        int tail;                                \
+    } name = {                                   \
+        { 0 },                                   \
+        0,                                       \
+        0 };
+
+struct circ_buf {
+	char *buf;
+	int head;
+	int tail;
+};
+
+/* Return count in buffer.  */
+#define CIRC_CNT(head,tail,size) (((head) - (tail)) & ((size)-1))
+
+/* Return space available, 0..size-1.  We always leave one free char
+   as a completely full buffer has head == tail, which is the same as
+   empty.  */
+#define CIRC_SPACE(head,tail,size) CIRC_CNT((tail),((head)+1),(size))
+
+/* Return count up to the end of the buffer.  Carefully avoid
+   accessing head and tail more than once, so they can change
+   underneath us without returning inconsistent results.  */
+#define CIRC_CNT_TO_END(head,tail,size) \
+	({int end = (size) - (tail); \
+	  int n = ((head) + end) & ((size)-1); \
+	  n < end ? n : end;})
+
+/* Return space available up to the end of the buffer.  */
+#define CIRC_SPACE_TO_END(head,tail,size) \
+	({int end = (size) - 1 - (head); \
+	  int n = (end + (tail)) & ((size)-1); \
+	  n <= end ? n : end+1;})
+
+
+int main(int ac, char **av)
+{
+    int size = 5;
+
+    if (ac > 8) {
+        size = atoi(*(av + 1));
+    }
+    printf("size-%d\n", size);
+
+    CIRC_BUF(foo, int, 5);
+    printf("sizeof(elt)=%lu\n", sizeof(foo.buf[0]));
+    printf("sizeof(buf)=%lu\n", sizeof(foo.buf));
+
+}

c/brlib/todo/circ_buf.h

@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * See Documentation/core-api/circular-buffers.rst for more information.
+ */
+
+#ifndef _LINUX_CIRC_BUF_H
+#define _LINUX_CIRC_BUF_H 1
+
+#define CIRC_BUF(name, type, bits)               \
+    struct s##name {                             \
+        type buf[1 << (bits)];                   \
+        int head;                                \
+        int tail;                                \
+    };
+
+struct circ_buf {
+	char *buf;
+	int head;
+	int tail;
+};
+
+/* Return count in buffer.  */
+#define CIRC_CNT(head,tail,size) (((head) - (tail)) & ((size)-1))
+
+/* Return space available, 0..size-1.  We always leave one free char
+   as a completely full buffer has head == tail, which is the same as
+   empty.  */
+#define CIRC_SPACE(head,tail,size) CIRC_CNT((tail),((head)+1),(size))
+
+/* Return count up to the end of the buffer.  Carefully avoid
+   accessing head and tail more than once, so they can change
+   underneath us without returning inconsistent results.  */
+#define CIRC_CNT_TO_END(head,tail,size) \
+	({int end = (size) - (tail); \
+	  int n = ((head) + end) & ((size)-1); \
+	  n < end ? n : end;})
+
+/* Return space available up to the end of the buffer.  */
+#define CIRC_SPACE_TO_END(head,tail,size) \
+	({int end = (size) - 1 - (head); \
+	  int n = (end + (tail)) & ((size)-1); \
+	  n <= end ? n : end+1;})
+
+#endif /* _LINUX_CIRC_BUF_H  */

c/brlib/todo/hashtest.c

@@ -0,0 +1,8 @@
+#include <stdio.h>
+#include "hash.h"
+
+int main()
+{
+    printf("foo\n");
+    return 1;
+}

c/brlib/todo/list_sort.c

@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Taken from linux kernel: lib/list_sort.c
+ */
+#include "list_sort.h"
+#include "list.h"
+#include "bits.h"
+#include "likely.h"
+
+/*
+ * Returns a list organized in an intermediate format suited
+ * to chaining of merge() calls: null-terminated, no reserved or
+ * sentinel head node, "prev" links not maintained.
+ */
+__attribute__((nonnull(2,3,4)))
+static struct list_head *merge(void *priv, list_cmp_func_t cmp,
+				struct list_head *a, struct list_head *b)
+{
+	struct list_head *head, **tail = &head;
+
+	for (;;) {
+		/* if equal, take 'a' -- important for sort stability */
+		if (cmp(priv, a, b) <= 0) {
+			*tail = a;
+			tail = &a->next;
+			a = a->next;
+			if (!a) {
+				*tail = b;
+				break;
+			}
+		} else {
+			*tail = b;
+			tail = &b->next;
+			b = b->next;
+			if (!b) {
+				*tail = a;
+				break;
+			}
+		}
+	}
+	return head;
+}
+
+/*
+ * Combine final list merge with restoration of standard doubly-linked
+ * list structure.  This approach duplicates code from merge(), but
+ * runs faster than the tidier alternatives of either a separate final
+ * prev-link restoration pass, or maintaining the prev links
+ * throughout.
+ */
+__attribute__((nonnull(2,3,4,5)))
+static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head,
+			struct list_head *a, struct list_head *b)
+{
+	struct list_head *tail = head;
+	u8 count = 0;
+
+	for (;;) {
+		/* if equal, take 'a' -- important for sort stability */
+		if (cmp(priv, a, b) <= 0) {
+			tail->next = a;
+			a->prev = tail;
+			tail = a;
+			a = a->next;
+			if (!a)
+				break;
+		} else {
+			tail->next = b;
+			b->prev = tail;
+			tail = b;
+			b = b->next;
+			if (!b) {
+				b = a;
+				break;
+			}
+		}
+	}
+
+	/* Finish linking remainder of list b on to tail */
+	tail->next = b;
+	do {
+		/*
+		 * If the merge is highly unbalanced (e.g. the input is
+		 * already sorted), this loop may run many iterations.
+		 * Continue callbacks to the client even though no
+		 * element comparison is needed, so the client's cmp()
+		 * routine can invoke cond_resched() periodically.
+		 */
+		if (unlikely(!++count))
+			cmp(priv, b, b);
+		b->prev = tail;
+		tail = b;
+		b = b->next;
+	} while (b);
+
+	/* And the final links to make a circular doubly-linked list */
+	tail->next = head;
+	head->prev = tail;
+}
+
+/**
+ * list_sort - sort a list
+ * @priv: private data, opaque to list_sort(), passed to @cmp
+ * @head: the list to sort
+ * @cmp: the elements comparison function
+ *
+ * The comparison function @cmp must return > 0 if @a should sort after
+ * @b ("@a > @b" if you want an ascending sort), and <= 0 if @a should
+ * sort before @b *or* their original order should be preserved.  It is
+ * always called with the element that came first in the input in @a,
+ * and list_sort is a stable sort, so it is not necessary to distinguish
+ * the @a < @b and @a == @b cases.
+ *
+ * This is compatible with two styles of @cmp function:
+ * - The traditional style which returns <0 / =0 / >0, or
+ * - Returning a boolean 0/1.
+ * The latter offers a chance to save a few cycles in the comparison
+ * (which is used by e.g. plug_ctx_cmp() in block/blk-mq.c).
+ *
+ * A good way to write a multi-word comparison is::
+ *
+ *	if (a->high != b->high)
+ *		return a->high > b->high;
+ *	if (a->middle != b->middle)
+ *		return a->middle > b->middle;
+ *	return a->low > b->low;
+ *
+ *
+ * This mergesort is as eager as possible while always performing at least
+ * 2:1 balanced merges.  Given two pending sublists of size 2^k, they are
+ * merged to a size-2^(k+1) list as soon as we have 2^k following elements.
+ *
+ * Thus, it will avoid cache thrashing as long as 3*2^k elements can
+ * fit into the cache.  Not quite as good as a fully-eager bottom-up
+ * mergesort, but it does use 0.2*n fewer comparisons, so is faster in
+ * the common case that everything fits into L1.
+ *
+ *
+ * The merging is controlled by "count", the number of elements in the
+ * pending lists.  This is beautifully simple code, but rather subtle.
+ *
+ * Each time we increment "count", we set one bit (bit k) and clear
+ * bits k-1 .. 0.  Each time this happens (except the very first time
+ * for each bit, when count increments to 2^k), we merge two lists of
+ * size 2^k into one list of size 2^(k+1).
+ *
+ * This merge happens exactly when the count reaches an odd multiple of
+ * 2^k, which is when we have 2^k elements pending in smaller lists,
+ * so it's safe to merge away two lists of size 2^k.
+ *
+ * After this happens twice, we have created two lists of size 2^(k+1),
+ * which will be merged into a list of size 2^(k+2) before we create
+ * a third list of size 2^(k+1), so there are never more than two pending.
+ *
+ * The number of pending lists of size 2^k is determined by the
+ * state of bit k of "count" plus two extra pieces of information:
+ *
+ * - The state of bit k-1 (when k == 0, consider bit -1 always set), and
+ * - Whether the higher-order bits are zero or non-zero (i.e.
+ *   is count >= 2^(k+1)).
+ *
+ * There are six states we distinguish.  "x" represents some arbitrary
+ * bits, and "y" represents some arbitrary non-zero bits:
+ * 0:  00x: 0 pending of size 2^k;           x pending of sizes < 2^k
+ * 1:  01x: 0 pending of size 2^k; 2^(k-1) + x pending of sizes < 2^k
+ * 2: x10x: 0 pending of size 2^k; 2^k     + x pending of sizes < 2^k
+ * 3: x11x: 1 pending of size 2^k; 2^(k-1) + x pending of sizes < 2^k
+ * 4: y00x: 1 pending of size 2^k; 2^k     + x pending of sizes < 2^k
+ * 5: y01x: 2 pending of size 2^k; 2^(k-1) + x pending of sizes < 2^k
+ * (merge and loop back to state 2)
+ *
+ * We gain lists of size 2^k in the 2->3 and 4->5 transitions (because
+ * bit k-1 is set while the more significant bits are non-zero) and
+ * merge them away in the 5->2 transition.  Note in particular that just
+ * before the 5->2 transition, all lower-order bits are 11 (state 3),
+ * so there is one list of each smaller size.
+ *
+ * When we reach the end of the input, we merge all the pending
+ * lists, from smallest to largest.  If you work through cases 2 to
+ * 5 above, you can see that the number of elements we merge with a list
+ * of size 2^k varies from 2^(k-1) (cases 3 and 5 when x == 0) to
+ * 2^(k+1) - 1 (second merge of case 5 when x == 2^(k-1) - 1).
+ */
+__attribute__((nonnull(2,3)))
+void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp)
+{
+	struct list_head *list = head->next, *pending = NULL;
+	size_t count = 0;	/* Count of pending */
+
+	if (list == head->prev)	/* Zero or one elements */
+		return;
+
+	/* Convert to a null-terminated singly-linked list. */
+	head->prev->next = NULL;
+
+	/*
+	 * Data structure invariants:
+	 * - All lists are singly linked and null-terminated; prev
+	 *   pointers are not maintained.
+	 * - pending is a prev-linked "list of lists" of sorted
+	 *   sublists awaiting further merging.
+	 * - Each of the sorted sublists is power-of-two in size.
+	 * - Sublists are sorted by size and age, smallest & newest at front.
+	 * - There are zero to two sublists of each size.
+	 * - A pair of pending sublists are merged as soon as the number
+	 *   of following pending elements equals their size (i.e.
+	 *   each time count reaches an odd multiple of that size).
+	 *   That ensures each later final merge will be at worst 2:1.
+	 * - Each round consists of:
+	 *   - Merging the two sublists selected by the highest bit
+	 *     which flips when count is incremented, and
+	 *   - Adding an element from the input as a size-1 sublist.
+	 */
+	do {
+		size_t bits;
+		struct list_head **tail = &pending;
+
+		/* Find the least-significant clear bit in count */
+		for (bits = count; bits & 1; bits >>= 1)
+			tail = &(*tail)->prev;
+		/* Do the indicated merge */
+		if (likely(bits)) {
+			struct list_head *a = *tail, *b = a->prev;
+
+			a = merge(priv, cmp, b, a);
+			/* Install the merged result in place of the inputs */
+			a->prev = b->prev;
+			*tail = a;
+		}
+
+		/* Move one element from input list to pending */
+		list->prev = pending;
+		pending = list;
+		list = list->next;
+		pending->next = NULL;
+		count++;
+	} while (list);
+
+	/* End of input; merge together all the pending lists. */
+	list = pending;
+	pending = pending->prev;
+	for (;;) {
+		struct list_head *next = pending->prev;
+
+		if (!next)
+			break;
+		list = merge(priv, cmp, pending, list);
+		pending = next;
+	}
+	/* The final merge, rebuilding prev links */
+	merge_final(priv, cmp, head, pending, list);
+}

c/brlib/todo/list_sort.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Taken from linux kernel: lib/list_sort.c
+ */
+
+#ifndef _BR_LIST_SORT_H
+#define _BR_LIST_SORT_H
+
+//#include <linux/types.h>
+
+struct list_head;
+
+typedef int __attribute__((nonnull(2,3))) (*list_cmp_func_t)(void *,
+		const struct list_head *, const struct list_head *);
+
+__attribute__((nonnull(2,3)))
+void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp);
+
+#endif  /* _BR_LIST_SORT */

c/brlib/todo/packed_struct.h

@@ -0,0 +1,46 @@
+#ifndef _LINUX_UNALIGNED_PACKED_STRUCT_H
+#define _LINUX_UNALIGNED_PACKED_STRUCT_H
+
+#include <linux/types.h>
+
+struct __una_u16 { u16 x; } __packed;
+struct __una_u32 { u32 x; } __packed;
+struct __una_u64 { u64 x; } __packed;
+
+static inline u16 __get_unaligned_cpu16(const void *p)
+{
+	const struct __una_u16 *ptr = (const struct __una_u16 *)p;
+	return ptr->x;
+}
+
+static inline u32 __get_unaligned_cpu32(const void *p)
+{
+	const struct __una_u32 *ptr = (const struct __una_u32 *)p;
+	return ptr->x;
+}
+
+static inline u64 __get_unaligned_cpu64(const void *p)
+{
+	const struct __una_u64 *ptr = (const struct __una_u64 *)p;
+	return ptr->x;
+}
+
+static inline void __put_unaligned_cpu16(u16 val, void *p)
+{
+	struct __una_u16 *ptr = (struct __una_u16 *)p;
+	ptr->x = val;
+}
+
+static inline void __put_unaligned_cpu32(u32 val, void *p)
+{
+	struct __una_u32 *ptr = (struct __una_u32 *)p;
+	ptr->x = val;
+}
+
+static inline void __put_unaligned_cpu64(u64 val, void *p)
+{
+	struct __una_u64 *ptr = (struct __una_u64 *)p;
+	ptr->x = val;
+}
+
+#endif /* _LINUX_UNALIGNED_PACKED_STRUCT_H */

c/brlib/todo/xxhash.c

@@ -0,0 +1,489 @@
+/*
+ * xxHash - Extremely Fast Hash algorithm
+ * Copyright (C) 2012-2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above
+ *     copyright notice, this list of conditions and the following disclaimer
+ *     in the documentation and/or other materials provided with the
+ *     distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation. This program is dual-licensed; you may select
+ * either version 2 of the GNU General Public License ("GPL") or BSD license
+ * ("BSD").
+ *
+ * You can contact the author at:
+ * - xxHash homepage: https://cyan4973.github.io/xxHash/
+ * - xxHash source repository: https://github.com/Cyan4973/xxHash
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <asm/byteorder.h>
+
+//#include <linux/compiler.h>
+// #include <linux/kernel.h>
+#include "xxhash.h"
+#include "bits.h"
+#include "asm/unaligned.h"
+
+/*-*************************************
+ * Macros
+ **************************************/
+#define xxh_rotl32(x, r) ((x << r) | (x >> (32 - r)))
+#define xxh_rotl64(x, r) ((x << r) | (x >> (64 - r)))
+
+#ifdef __LITTLE_ENDIAN
+# define XXH_CPU_LITTLE_ENDIAN 1
+#else
+# define XXH_CPU_LITTLE_ENDIAN 0
+#endif
+
+/*-*************************************
+ * Constants
+ **************************************/
+static const uint32_t PRIME32_1 = 2654435761U;
+static const uint32_t PRIME32_2 = 2246822519U;
+static const uint32_t PRIME32_3 = 3266489917U;
+static const uint32_t PRIME32_4 =  668265263U;
+static const uint32_t PRIME32_5 =  374761393U;
+
+static const uint64_t PRIME64_1 = 11400714785074694791ULL;
+static const uint64_t PRIME64_2 = 14029467366897019727ULL;
+static const uint64_t PRIME64_3 =  1609587929392839161ULL;
+static const uint64_t PRIME64_4 =  9650029242287828579ULL;
+static const uint64_t PRIME64_5 =  2870177450012600261ULL;
+
+/*-**************************
+ *  Utils
+ ***************************/
+void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src)
+{
+	memcpy(dst, src, sizeof(*dst));
+}
+
+void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src)
+{
+	memcpy(dst, src, sizeof(*dst));
+}
+
+/*-***************************
+ * Simple Hash Functions
+ ****************************/
+static uint32_t xxh32_round(uint32_t seed, const uint32_t input)
+{
+	seed += input * PRIME32_2;
+	seed = xxh_rotl32(seed, 13);
+	seed *= PRIME32_1;
+	return seed;
+}
+
+uint32_t xxh32(const void *input, const size_t len, const uint32_t seed)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *b_end = p + len;
+	uint32_t h32;
+
+	if (len >= 16) {
+		const uint8_t *const limit = b_end - 16;
+		uint32_t v1 = seed + PRIME32_1 + PRIME32_2;
+		uint32_t v2 = seed + PRIME32_2;
+		uint32_t v3 = seed + 0;
+		uint32_t v4 = seed - PRIME32_1;
+
+		do {
+			v1 = xxh32_round(v1, get_unaligned_le32(p));
+			p += 4;
+			v2 = xxh32_round(v2, get_unaligned_le32(p));
+			p += 4;
+			v3 = xxh32_round(v3, get_unaligned_le32(p));
+			p += 4;
+			v4 = xxh32_round(v4, get_unaligned_le32(p));
+			p += 4;
+		} while (p <= limit);
+
+		h32 = xxh_rotl32(v1, 1) + xxh_rotl32(v2, 7) +
+			xxh_rotl32(v3, 12) + xxh_rotl32(v4, 18);
+	} else {
+		h32 = seed + PRIME32_5;
+	}
+
+	h32 += (uint32_t)len;
+
+	while (p + 4 <= b_end) {
+		h32 += get_unaligned_le32(p) * PRIME32_3;
+		h32 = xxh_rotl32(h32, 17) * PRIME32_4;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h32 += (*p) * PRIME32_5;
+		h32 = xxh_rotl32(h32, 11) * PRIME32_1;
+		p++;
+	}
+
+	h32 ^= h32 >> 15;
+	h32 *= PRIME32_2;
+	h32 ^= h32 >> 13;
+	h32 *= PRIME32_3;
+	h32 ^= h32 >> 16;
+
+	return h32;
+}
+
+static uint64_t xxh64_round(uint64_t acc, const uint64_t input)
+{
+	acc += input * PRIME64_2;
+	acc = xxh_rotl64(acc, 31);
+	acc *= PRIME64_1;
+	return acc;
+}
+
+static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val)
+{
+	val = xxh64_round(0, val);
+	acc ^= val;
+	acc = acc * PRIME64_1 + PRIME64_4;
+	return acc;
+}
+
+uint64_t xxh64(const void *input, const size_t len, const uint64_t seed)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *const b_end = p + len;
+	uint64_t h64;
+
+	if (len >= 32) {
+		const uint8_t *const limit = b_end - 32;
+		uint64_t v1 = seed + PRIME64_1 + PRIME64_2;
+		uint64_t v2 = seed + PRIME64_2;
+		uint64_t v3 = seed + 0;
+		uint64_t v4 = seed - PRIME64_1;
+
+		do {
+			v1 = xxh64_round(v1, get_unaligned_le64(p));
+			p += 8;
+			v2 = xxh64_round(v2, get_unaligned_le64(p));
+			p += 8;
+			v3 = xxh64_round(v3, get_unaligned_le64(p));
+			p += 8;
+			v4 = xxh64_round(v4, get_unaligned_le64(p));
+			p += 8;
+		} while (p <= limit);
+
+		h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) +
+			xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18);
+		h64 = xxh64_merge_round(h64, v1);
+		h64 = xxh64_merge_round(h64, v2);
+		h64 = xxh64_merge_round(h64, v3);
+		h64 = xxh64_merge_round(h64, v4);
+
+	} else {
+		h64  = seed + PRIME64_5;
+	}
+
+	h64 += (uint64_t)len;
+
+	while (p + 8 <= b_end) {
+		const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p));
+
+		h64 ^= k1;
+		h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4;
+		p += 8;
+	}
+
+	if (p + 4 <= b_end) {
+		h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1;
+		h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h64 ^= (*p) * PRIME64_5;
+		h64 = xxh_rotl64(h64, 11) * PRIME64_1;
+		p++;
+	}
+
+	h64 ^= h64 >> 33;
+	h64 *= PRIME64_2;
+	h64 ^= h64 >> 29;
+	h64 *= PRIME64_3;
+	h64 ^= h64 >> 32;
+
+	return h64;
+}
+
+/*-**************************************************
+ * Advanced Hash Functions
+ ***************************************************/
+void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed)
+{
+	/* use a local state for memcpy() to avoid strict-aliasing warnings */
+	struct xxh32_state state;
+
+	memset(&state, 0, sizeof(state));
+	state.v1 = seed + PRIME32_1 + PRIME32_2;
+	state.v2 = seed + PRIME32_2;
+	state.v3 = seed + 0;
+	state.v4 = seed - PRIME32_1;
+	memcpy(statePtr, &state, sizeof(state));
+}
+
+void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed)
+{
+	/* use a local state for memcpy() to avoid strict-aliasing warnings */
+	struct xxh64_state state;
+
+	memset(&state, 0, sizeof(state));
+	state.v1 = seed + PRIME64_1 + PRIME64_2;
+	state.v2 = seed + PRIME64_2;
+	state.v3 = seed + 0;
+	state.v4 = seed - PRIME64_1;
+	memcpy(statePtr, &state, sizeof(state));
+}
+
+int xxh32_update(struct xxh32_state *state, const void *input, const size_t len)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *const b_end = p + len;
+
+	if (input == NULL)
+		return -EINVAL;
+
+	state->total_len_32 += (uint32_t)len;
+	state->large_len |= (len >= 16) | (state->total_len_32 >= 16);
+
+	if (state->memsize + len < 16) { /* fill in tmp buffer */
+		memcpy((uint8_t *)(state->mem32) + state->memsize, input, len);
+		state->memsize += (uint32_t)len;
+		return 0;
+	}
+
+	if (state->memsize) { /* some data left from previous update */
+		const uint32_t *p32 = state->mem32;
+
+		memcpy((uint8_t *)(state->mem32) + state->memsize, input,
+			16 - state->memsize);
+
+		state->v1 = xxh32_round(state->v1, get_unaligned_le32(p32));
+		p32++;
+		state->v2 = xxh32_round(state->v2, get_unaligned_le32(p32));
+		p32++;
+		state->v3 = xxh32_round(state->v3, get_unaligned_le32(p32));
+		p32++;
+		state->v4 = xxh32_round(state->v4, get_unaligned_le32(p32));
+		p32++;
+
+		p += 16-state->memsize;
+		state->memsize = 0;
+	}
+
+	if (p <= b_end - 16) {
+		const uint8_t *const limit = b_end - 16;
+		uint32_t v1 = state->v1;
+		uint32_t v2 = state->v2;
+		uint32_t v3 = state->v3;
+		uint32_t v4 = state->v4;
+
+		do {
+			v1 = xxh32_round(v1, get_unaligned_le32(p));
+			p += 4;
+			v2 = xxh32_round(v2, get_unaligned_le32(p));
+			p += 4;
+			v3 = xxh32_round(v3, get_unaligned_le32(p));
+			p += 4;
+			v4 = xxh32_round(v4, get_unaligned_le32(p));
+			p += 4;
+		} while (p <= limit);
+
+		state->v1 = v1;
+		state->v2 = v2;
+		state->v3 = v3;
+		state->v4 = v4;
+	}
+
+	if (p < b_end) {
+		memcpy(state->mem32, p, (size_t)(b_end-p));
+		state->memsize = (uint32_t)(b_end-p);
+	}
+
+	return 0;
+}
+
+uint32_t xxh32_digest(const struct xxh32_state *state)
+{
+	const uint8_t *p = (const uint8_t *)state->mem32;
+	const uint8_t *const b_end = (const uint8_t *)(state->mem32) +
+		state->memsize;
+	uint32_t h32;
+
+	if (state->large_len) {
+		h32 = xxh_rotl32(state->v1, 1) + xxh_rotl32(state->v2, 7) +
+			xxh_rotl32(state->v3, 12) + xxh_rotl32(state->v4, 18);
+	} else {
+		h32 = state->v3 /* == seed */ + PRIME32_5;
+	}
+
+	h32 += state->total_len_32;
+
+	while (p + 4 <= b_end) {
+		h32 += get_unaligned_le32(p) * PRIME32_3;
+		h32 = xxh_rotl32(h32, 17) * PRIME32_4;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h32 += (*p) * PRIME32_5;
+		h32 = xxh_rotl32(h32, 11) * PRIME32_1;
+		p++;
+	}
+
+	h32 ^= h32 >> 15;
+	h32 *= PRIME32_2;
+	h32 ^= h32 >> 13;
+	h32 *= PRIME32_3;
+	h32 ^= h32 >> 16;
+
+	return h32;
+}
+
+int xxh64_update(struct xxh64_state *state, const void *input, const size_t len)
+{
+	const uint8_t *p = (const uint8_t *)input;
+	const uint8_t *const b_end = p + len;
+
+	if (input == NULL)
+		return -EINVAL;
+
+	state->total_len += len;
+
+	if (state->memsize + len < 32) { /* fill in tmp buffer */
+		memcpy(((uint8_t *)state->mem64) + state->memsize, input, len);
+		state->memsize += (uint32_t)len;
+		return 0;
+	}
+
+	if (state->memsize) { /* tmp buffer is full */
+		uint64_t *p64 = state->mem64;
+
+		memcpy(((uint8_t *)p64) + state->memsize, input,
+			32 - state->memsize);
+
+		state->v1 = xxh64_round(state->v1, get_unaligned_le64(p64));
+		p64++;
+		state->v2 = xxh64_round(state->v2, get_unaligned_le64(p64));
+		p64++;
+		state->v3 = xxh64_round(state->v3, get_unaligned_le64(p64));
+		p64++;
+		state->v4 = xxh64_round(state->v4, get_unaligned_le64(p64));
+
+		p += 32 - state->memsize;
+		state->memsize = 0;
+	}
+
+	if (p + 32 <= b_end) {
+		const uint8_t *const limit = b_end - 32;
+		uint64_t v1 = state->v1;
+		uint64_t v2 = state->v2;
+		uint64_t v3 = state->v3;
+		uint64_t v4 = state->v4;
+
+		do {
+			v1 = xxh64_round(v1, get_unaligned_le64(p));
+			p += 8;
+			v2 = xxh64_round(v2, get_unaligned_le64(p));
+			p += 8;
+			v3 = xxh64_round(v3, get_unaligned_le64(p));
+			p += 8;
+			v4 = xxh64_round(v4, get_unaligned_le64(p));
+			p += 8;
+		} while (p <= limit);
+
+		state->v1 = v1;
+		state->v2 = v2;
+		state->v3 = v3;
+		state->v4 = v4;
+	}
+
+	if (p < b_end) {
+		memcpy(state->mem64, p, (size_t)(b_end-p));
+		state->memsize = (uint32_t)(b_end - p);
+	}
+
+	return 0;
+}
+
+uint64_t xxh64_digest(const struct xxh64_state *state)
+{
+	const uint8_t *p = (const uint8_t *)state->mem64;
+	const uint8_t *const b_end = (const uint8_t *)state->mem64 +
+		state->memsize;
+	uint64_t h64;
+
+	if (state->total_len >= 32) {
+		const uint64_t v1 = state->v1;
+		const uint64_t v2 = state->v2;
+		const uint64_t v3 = state->v3;
+		const uint64_t v4 = state->v4;
+
+		h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) +
+			xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18);
+		h64 = xxh64_merge_round(h64, v1);
+		h64 = xxh64_merge_round(h64, v2);
+		h64 = xxh64_merge_round(h64, v3);
+		h64 = xxh64_merge_round(h64, v4);
+	} else {
+		h64  = state->v3 + PRIME64_5;
+	}
+
+	h64 += (uint64_t)state->total_len;
+
+	while (p + 8 <= b_end) {
+		const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p));
+
+		h64 ^= k1;
+		h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4;
+		p += 8;
+	}
+
+	if (p + 4 <= b_end) {
+		h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1;
+		h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+		p += 4;
+	}
+
+	while (p < b_end) {
+		h64 ^= (*p) * PRIME64_5;
+		h64 = xxh_rotl64(h64, 11) * PRIME64_1;
+		p++;
+	}
+
+	h64 ^= h64 >> 33;
+	h64 *= PRIME64_2;
+	h64 ^= h64 >> 29;
+	h64 *= PRIME64_3;
+	h64 ^= h64 >> 32;
+
+	return h64;
+}

c/brlib/todo/xxhash.h

@@ -0,0 +1,259 @@
+/*
+ * xxHash - Extremely Fast Hash algorithm
+ * Copyright (C) 2012-2016, Yann Collet.
+ *
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above
+ *     copyright notice, this list of conditions and the following disclaimer
+ *     in the documentation and/or other materials provided with the
+ *     distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation. This program is dual-licensed; you may select
+ * either version 2 of the GNU General Public License ("GPL") or BSD license
+ * ("BSD").
+ *
+ * You can contact the author at:
+ * - xxHash homepage: https://cyan4973.github.io/xxHash/
+ * - xxHash source repository: https://github.com/Cyan4973/xxHash
+ */
+
+/*
+ * Notice extracted from xxHash homepage:
+ *
+ * xxHash is an extremely fast Hash algorithm, running at RAM speed limits.
+ * It also successfully passes all tests from the SMHasher suite.
+ *
+ * Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2
+ * Duo @3GHz)
+ *
+ * Name            Speed       Q.Score   Author
+ * xxHash          5.4 GB/s     10
+ * CrapWow         3.2 GB/s      2       Andrew
+ * MumurHash 3a    2.7 GB/s     10       Austin Appleby
+ * SpookyHash      2.0 GB/s     10       Bob Jenkins
+ * SBox            1.4 GB/s      9       Bret Mulvey
+ * Lookup3         1.2 GB/s      9       Bob Jenkins
+ * SuperFastHash   1.2 GB/s      1       Paul Hsieh
+ * CityHash64      1.05 GB/s    10       Pike & Alakuijala
+ * FNV             0.55 GB/s     5       Fowler, Noll, Vo
+ * CRC32           0.43 GB/s     9
+ * MD5-32          0.33 GB/s    10       Ronald L. Rivest
+ * SHA1-32         0.28 GB/s    10
+ *
+ * Q.Score is a measure of quality of the hash function.
+ * It depends on successfully passing SMHasher test set.
+ * 10 is a perfect score.
+ *
+ * A 64-bits version, named xxh64 offers much better speed,
+ * but for 64-bits applications only.
+ * Name     Speed on 64 bits    Speed on 32 bits
+ * xxh64       13.8 GB/s            1.9 GB/s
+ * xxh32        6.8 GB/s            6.0 GB/s
+ */
+
+#ifndef XXHASH_H
+#define XXHASH_H
+
+#include <linux/types.h>
+
+/*-****************************
+ * Simple Hash Functions
+ *****************************/
+
+/**
+ * xxh32() - calculate the 32-bit hash of the input with a given seed.
+ *
+ * @input:  The data to hash.
+ * @length: The length of the data to hash.
+ * @seed:   The seed can be used to alter the result predictably.
+ *
+ * Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s
+ *
+ * Return:  The 32-bit hash of the data.
+ */
+uint32_t xxh32(const void *input, size_t length, uint32_t seed);
+
+/**
+ * xxh64() - calculate the 64-bit hash of the input with a given seed.
+ *
+ * @input:  The data to hash.
+ * @length: The length of the data to hash.
+ * @seed:   The seed can be used to alter the result predictably.
+ *
+ * This function runs 2x faster on 64-bit systems, but slower on 32-bit systems.
+ *
+ * Return:  The 64-bit hash of the data.
+ */
+uint64_t xxh64(const void *input, size_t length, uint64_t seed);
+
+/**
+ * xxhash() - calculate wordsize hash of the input with a given seed
+ * @input:  The data to hash.
+ * @length: The length of the data to hash.
+ * @seed:   The seed can be used to alter the result predictably.
+ *
+ * If the hash does not need to be comparable between machines with
+ * different word sizes, this function will call whichever of xxh32()
+ * or xxh64() is faster.
+ *
+ * Return:  wordsize hash of the data.
+ */
+
+static inline unsigned long xxhash(const void *input, size_t length,
+				   uint64_t seed)
+{
+#if BITS_PER_LONG == 64
+       return xxh64(input, length, seed);
+#else
+       return xxh32(input, length, seed);
+#endif
+}
+
+/*-****************************
+ * Streaming Hash Functions
+ *****************************/
+
+/*
+ * These definitions are only meant to allow allocation of XXH state
+ * statically, on stack, or in a struct for example.
+ * Do not use members directly.
+ */
+
+/**
+ * struct xxh32_state - private xxh32 state, do not use members directly
+ */
+struct xxh32_state {
+	uint32_t total_len_32;
+	uint32_t large_len;
+	uint32_t v1;
+	uint32_t v2;
+	uint32_t v3;
+	uint32_t v4;
+	uint32_t mem32[4];
+	uint32_t memsize;
+};
+
+/**
+ * struct xxh32_state - private xxh64 state, do not use members directly
+ */
+struct xxh64_state {
+	uint64_t total_len;
+	uint64_t v1;
+	uint64_t v2;
+	uint64_t v3;
+	uint64_t v4;
+	uint64_t mem64[4];
+	uint32_t memsize;
+};
+
+/**
+ * xxh32_reset() - reset the xxh32 state to start a new hashing operation
+ *
+ * @state: The xxh32 state to reset.
+ * @seed:  Initialize the hash state with this seed.
+ *
+ * Call this function on any xxh32_state to prepare for a new hashing operation.
+ */
+void xxh32_reset(struct xxh32_state *state, uint32_t seed);
+
+/**
+ * xxh32_update() - hash the data given and update the xxh32 state
+ *
+ * @state:  The xxh32 state to update.
+ * @input:  The data to hash.
+ * @length: The length of the data to hash.
+ *
+ * After calling xxh32_reset() call xxh32_update() as many times as necessary.
+ *
+ * Return:  Zero on success, otherwise an error code.
+ */
+int xxh32_update(struct xxh32_state *state, const void *input, size_t length);
+
+/**
+ * xxh32_digest() - produce the current xxh32 hash
+ *
+ * @state: Produce the current xxh32 hash of this state.
+ *
+ * A hash value can be produced at any time. It is still possible to continue
+ * inserting input into the hash state after a call to xxh32_digest(), and
+ * generate new hashes later on, by calling xxh32_digest() again.
+ *
+ * Return: The xxh32 hash stored in the state.
+ */
+uint32_t xxh32_digest(const struct xxh32_state *state);
+
+/**
+ * xxh64_reset() - reset the xxh64 state to start a new hashing operation
+ *
+ * @state: The xxh64 state to reset.
+ * @seed:  Initialize the hash state with this seed.
+ */
+void xxh64_reset(struct xxh64_state *state, uint64_t seed);
+
+/**
+ * xxh64_update() - hash the data given and update the xxh64 state
+ * @state:  The xxh64 state to update.
+ * @input:  The data to hash.
+ * @length: The length of the data to hash.
+ *
+ * After calling xxh64_reset() call xxh64_update() as many times as necessary.
+ *
+ * Return:  Zero on success, otherwise an error code.
+ */
+int xxh64_update(struct xxh64_state *state, const void *input, size_t length);
+
+/**
+ * xxh64_digest() - produce the current xxh64 hash
+ *
+ * @state: Produce the current xxh64 hash of this state.
+ *
+ * A hash value can be produced at any time. It is still possible to continue
+ * inserting input into the hash state after a call to xxh64_digest(), and
+ * generate new hashes later on, by calling xxh64_digest() again.
+ *
+ * Return: The xxh64 hash stored in the state.
+ */
+uint64_t xxh64_digest(const struct xxh64_state *state);
+
+/*-**************************
+ * Utils
+ ***************************/
+
+/**
+ * xxh32_copy_state() - copy the source state into the destination state
+ *
+ * @src: The source xxh32 state.
+ * @dst: The destination xxh32 state.
+ */
+void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src);
+
+/**
+ * xxh64_copy_state() - copy the source state into the destination state
+ *
+ * @src: The source xxh64 state.
+ * @dst: The destination xxh64 state.
+ */
+void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src);
+
+#endif /* XXHASH_H */

config/home/.bashrc.br

@@ -0,0 +1,258 @@
+#!/usr/bin/env bash
+#
+# ~/.bashrc.br - user specific initialization
+#
+# (C) Bruno Raoult ("br"), 2001-2023
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+# Usage: to be invoked from .bashrc.
+# i.e., add at the end of .bashrc:
+# [ -f "$HOME/.bashrc.$USER" ] && . "$HOME/.bashrc.$USER"
+
+# _var_del() - remove an element from a colon-separated list.
+# $1: name (reference) of a colon separated list
+# $2: element to remove (string)
+#
+# _var_del() removes every occurrence of $2, if there are more than 1,
+# and leaves $1 unchanged if $2 is not present.
+#
+# Example:
+# With VAR's value being "foo:bar:quax:bar". Using "_var_del VAR bar" will
+# leave VAR with the value "foo:quax".
+_var_del() {
+    local -n _p_del=$1
+    local _l=":$_p_del:"
+
+    while [[ $_l =~ :$2: ]]; do
+          _l=${_l//:$2:/:}
+    done
+    _l=${_l%:}
+    _l=${_l#:}
+    _p_del="$_l"
+}
+
+# _var_prepend() - prepend element to colon-separated variable.
+# $1: variable name (reference)
+# $2: element to add (string)
+#
+# Any occurrence of $2 in $1 is first removed, then $2 is added at $1 beginning.
+#
+# Example:
+# With VAR's value being "foo:bar:quax:bar". Using "_var_prepend VAR bar"
+# will leave VAR with the value "bar:foo:quax".
+_var_prepend() {
+    local -n _p_prepend=$1
+
+    _var_del _p_prepend "$2"
+    [[ -z $_p_prepend ]] && _p_prepend="$2" && return
+    _p_prepend="$2:$_p_prepend"
+}
+
+# _var_append() - append element to colon-separated variable.
+# $1: variable name (reference)
+# $2: element to add (string)
+#
+# Any occurrence of $2 in $1 is first removed, then $2 is added at $1 end.
+#
+# Example:
+# With VAR's value being "foo:bar:quax:bar". Using "_var_append VAR bar"
+# will leave VAR with the value "foo:quax:bar".
+_var_append() {
+    local -n _p_append=$1
+
+    _var_del _p_append "$2"
+    [[ -z $_p_append ]] && _p_append="$2" && return
+    _p_append="$_p_append:$2"
+}
+
+# adjust PATH. Below paths will be added at beginning.
+_lpath=("$HOME/bin/$(uname -s)-$(uname -m)"
+        "$HOME/bin"
+        #"$HOME/.cargo/bin"
+        "/usr/local/bin")
+
+# loop array in reverse order. Note: We do not test for path existence and add it
+# unconditionally, to avoid automounter interference.
+for (( _i = ${#_lpath[@]} - 1; _i >= 0; --_i )); do
+    _var_prepend PATH "${_lpath[_i]}"
+done
+unset _lpath
+
+# why is it in default Ubuntu path ?
+_var_del PATH /snap/bin
+
+# enable core file
+ulimit -Sc 102400                                 # in 1024 bytes, 100Mb
+
+# ... and set PAGER to less (for man(1) and others)
+if hash less 2>/dev/null; then
+    export PAGER=less
+    # do not clear screen after "less", exit immediately if one page only
+    export LESS="-XFB"
+    # ... and just alias more... to less ;-)
+    alias more=less
+fi
+
+# no output split for dc and bc / make bc silent
+export DC_LINE_LENGTH=0
+export BC_LINE_LENGTH=0
+export BC_ENV_ARGS=--quiet
+
+# both ubuntu and debian assume we want colors if TERM contains "color"
+# this is surely not true, as TERM is often forced by terminal emulator
+# shellcheck disable=SC2154
+PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
+case "$TERM" in
+    xterm*|rxvt*)
+        PS1="\[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\]$PS1"
+        ;;
+    *)
+        ;;
+esac
+
+# trim prompt path
+export PROMPT_DIRTRIM=3
+
+# find a suitable editor
+e() {
+    $VISUAL "$@"
+}
+export -f e
+if hash emacs 2>/dev/null; then
+    # uncomment below to use full emacs
+    #export EDITOR=emacs
+    # ... OR: uncomment below to use emacsclient
+    #export ALTERNATE_EDITOR="/usr/bin/emacs"
+    #export EDITOR="emacs.sh"
+    #alias emacs="emacs.sh"
+    export ALTERNATE_EDITOR=""
+    export VISUAL="emacsclient -c"
+    alias emacs="emacsclient -c"
+    #alias crontab="VISUAL=emacsclient crontab -e"
+    #alias crontab="emacs-crontab.sh"
+else
+    # emacs clones, then vim/vi, then... whatever left.
+    _VISUALS=(zile jed mg e3em vim vi nano ed)
+
+    for e in "${_VISUALS[@]}"; do
+        if hash "$e" 2>/dev/null; then
+            export VISUAL="$e"
+            break
+        fi
+    done
+    unset _VISUALS
+fi
+export EDITOR=$VISUAL
+
+# append to the history file, don't overwrite it
+shopt -s histappend
+# write history after each command
+export PROMPT_COMMAND="history -a"
+# Add timestamp in history
+export HISTTIMEFORMAT="%d/%m %H:%M "
+# ignore history dups, delete all previous dups
+export HISTCONTROL="ignorespace:ignoredups:erasedups"
+# ignore these in history
+export HISTIGNORE="history *:h:hl:hll:hlll"
+# history size
+HISTSIZE=5000
+HISTFILESIZE=5000
+
+# remove new stupid Debian "ls" quoting, and colors...
+# Many complains, one of them:
+#    https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=813164#226
+export QUOTING_STYLE=literal
+[[ -v BASH_ALIASES[ls] ]] && unalias ls
+
+# avoid these stupid systemd defaults (horizontal scroll and pager)
+alias systemctl="systemctl --no-pager --full"
+
+# aliases for ls and history
+alias l='ls -F'
+alias ls='ls -F'
+alias l1='ls -1F'
+alias la='ls -AF'
+alias ll='ls -lF'
+alias lla='ls -lAF'
+alias ldl='ls -l | grep ^d'
+[[ -v BASH_ALIASES[lrt] ]] && unalias lrt
+lrt() {
+    local -i _l=20
+    if (( $# > 0 )) && [[ $1 =~ [[:digit:]]+ ]]; then
+        _l="$1"
+        shift
+    fi
+    # shellcheck disable=2012
+    ls -lrt "${1:-.}" | tail -"$_l"
+}
+[[ -v BASH_ALIASES[lart] ]] && unalias lart
+lart() {
+    local -i _l=20
+    if (( $# > 0 )) && [[ $1 =~ [[:digit:]]+ ]]; then
+        _l="$1"
+        shift
+    fi
+    # shellcheck disable=2012
+    ls -laFrt "${1:-.}" | tail -"$_l"
+}
+
+alias h="history   10"                            # short
+alias hl="history  25"                            # long
+alias hll="history 100"                           # very long
+alias hlll="history"                              # all history
+
+# user temp directory
+export USERTMP=~/tmp
+
+# misc aliases
+alias fuck='sudo $(history -p \!\!)'
+alias diff='diff -u'
+# fdiff() - compare two files with same name
+# parameters:
+# $1: first file
+# $2: second file directory
+#
+# fdiff will compare (diff) $1 with a file of basename $1 in $2 directory.
+# Examples:
+# % fdiff .bashrc ~                # compare .bashrc with ~/.bashrc
+# % fdiff /tmp/.bashrc /home/br/   # compare /tmp/.bashrc with /home/br/.bashrc
+
+fdiff () {
+    local file1="$1"                              # file to compare
+    local file2="$2/${file1##*/}"                 # file2 with path
+
+    diff "$file1" "$file2"
+}
+
+# I am used to rehash...
+# rehash - manage bash's remembered commands paths
+# $1...: Only forget those commands
+rehash() {
+    if (($#)); then
+        hash -d "$@"
+    else
+        hash -r
+    fi
+}
+
+# french-> english and english->french translation
+alias trans="trans.sh"
+alias rtrans="trans.sh -fen -tfr"
+
+# host specific initialization
+# shellcheck disable=SC1090
+[ -f "$HOME/.bashrc.$USER.$(hostname)" ] && . "$HOME/.bashrc.$USER.$(hostname)"
+
+# Indent style for emacs
+# Local Variables:
+# mode: shell-script
+# sh-basic-offset: 4
+# sh-indentation: 4
+# indent-tabs-mode: nil
+# End:

config/home/.bashrc.br.lorien

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+#
+# ~/.bashrc.br.lorien - host specific initialization
+#
+# (C) Bruno Raoult ("br"), 2001-2023
+# Licensed under the GNU General Public License v3.0 or later.
+# Some rights reserved. See COPYING.
+#
+# You should have received a copy of the GNU General Public License along with this
+# program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+#
+# SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+#
+# Usage: to be invoked from .bashrc.$USER
+# i.e., add at the end of .bashrc.$USER:
+# [ -f "$HOME/.bashrc.$USER.$(hostname)" ] && . "$HOME/.bashrc.$USER.$(hostname)"
+
+# look for a pdf viewer
+hash atril 2> /dev/null && alias acroread=atril
+
+# mysql aliases. Will match any "[client-XXX]" lines in ~/.my.cnf
+# and generate "myXXX" aliases.
+if [[ -r ~/.my.cnf ]]; then
+    mapfile -t MYSQL_ARRAY < ~/.my.cnf
+
+    for line in "${MYSQL_ARRAY[@]}"; do
+        if [[ $line =~ ^\[client-(.+)\]$ ]]; then
+            SUFFIX="${BASH_REMATCH[1]}"
+            # shellcheck disable=SC2139,SC2140
+            alias my"$SUFFIX"="mysql --defaults-group-suffix=-$SUFFIX"
+        fi
+    done
+fi
+
+# shortcuts to commonly used directories
+# alias dev="cd ~/dev/www/cf.bodi"                     # Clash of Clans
+alias eud="cd ~/dev/eudyptula; . ./bin/ENV.sh"         # Eudyptula
+alias aoc="cd ~/dev/advent-of-code/2022/; . ../env.sh" # Advent of Code
+alias wchess="cd ~/dev/www/com.raoult/devs/chess"      # raoult.com chess
+alias chess="cd ~/dev/brchess; . env.sh"               # brchess
+alias tools="cd ~/dev/tools"                           # tools
+alias brlib="cd ~/dev/tools/c/brlib"                   # brlib dir/repo
+
+# Indent style for emacs
+# Local Variables:
+# mode: shell-script
+# sh-basic-offset: 4
+# sh-indentation: 4
+# indent-tabs-mode: nil
+# End:

config/home/.emacs.d/eowyn.el

@@ -0,0 +1,58 @@
+;; ~/.emacs.d/lorien.el
+;;
+;; emacs configuration - this file will be loaded only when emacs runs on lorien.
+;;
+;; br, 2010-2019
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; pre-load often-visited files
+
+;; avoids calling this twice
+(when (not (boundp 'my/eowyn-loaded))
+  ;; I put mainfile (current project) in variable.
+  (setq
+    my/mainfile "~/dev/advent-of-code/2019/RESULTS.txt"
+    my/eowyn-loaded t)
+
+  ;; mysql CoC connection
+  (defun my/connect-coc ()
+    (interactive)
+    (my/sql-connect-preset 'coc))
+
+  ;; shortcuts for tramp
+  ;; (my/add-to-list
+  ;;   'directory-abbrev-alist
+  ;;   '(("^/root" . "/su:/")
+  ;;      ("^/rebel" . "/ssh:arwen:www/cf.bodi/rebels21/")
+  ;;      ("^/strat" . "/ssh:arwen:www/cf.bodi/strat-dom/")))
+
+  (defconst my/loaded-files-at-startup
+    (list
+      my/mainfile
+      user-init-file
+      (concat user-emacs-directory "emacs-cheatsheet.org"))
+      ;; (concat (getenv "HOME") "/dev/g910-gkey-macro-support/lib/data_mappers/char_uinput_mapper.py")
+      ;; (concat (getenv "HOME") "/Documents/org/boot-disk.org"))
+    "personal files always loaded at startup (no visible window).")
+
+  (let ((num 1))
+    (dolist
+      (filename my/loaded-files-at-startup)
+      (if (file-exists-p filename)
+        (progn
+          ;; set variable "my/buffer-1" to buffer returned by find-file
+          (set
+            (intern (concat "my/buffer-" (number-to-string num)))
+            (find-file-noselect filename nil nil nil))
+          (message "file: [%s] loaded." filename))
+        (message "cannot load file: [%s]." filename))
+        (cl-incf num)))
+
+  ;; set windows for current work buffers
+  (when (boundp 'my/graphic-loaded)
+    (set-window-buffer my/main-window my/buffer-1)
+    ;;(set-window-buffer my/upper-window (get-buffer "*Messages*"))
+    (set-window-buffer my/upper-window "*Messages*")
+    (set-window-buffer my/below-window my/buffer-3)))
+
+;; (set-window-buffer current-buffer (get-buffer "*messages*"))))
+;; (set-window-buffer "*messages*")

config/home/.emacs.d/graphic.el

@@ -0,0 +1,22 @@
+;; ~/.emacs.d/graphic.el
+;;
+;; emacs configuration - this file will be loaded only when emacs runs on graphic
+;; system.
+;;
+;; br, 2010-2019
+
+;; avoids calling this twice
+(when (not (boundp 'my/graphic-loaded))
+  ;; disable toolbar
+  (tool-bar-mode -1)
+
+  ;; initial frame size
+  (set-frame-size (selected-frame) 180 50)
+
+  (setq
+    ;; split windows and assign them references
+    my/upper-window (selected-window)
+    my/main-window  (split-window-right)
+    my/below-window (split-window-below)
+
+    my/graphic-loaded t))

config/home/.emacs.d/lorien.el

@@ -0,0 +1,141 @@
+;; ~/.emacs.d/lorien.el
+;;
+;; Emacs configuration - this file will be loaded only when run on lorien.
+;;
+;; br, 2010-2019
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; pre-load often-visited files
+
+;; avoids calling this twice
+(when (not (boundp 'my/lorien-loaded))
+  (setq my/lorien-loaded t)
+
+  ;; use ESC as C-g
+  ;; (global-set-key [escape] 'keyboard-escape-quit)
+  ;; (global-unset-key [escape])
+  (define-key key-translation-map (kbd "ESC") (kbd "C-g"))
+
+  ;; mail
+  (require 'message)
+  (setq message-send-mail-function 'smtpmail-send-it
+        smtpmail-default-smtp-server "localhost"
+        smtpmail-smtp-server "localhost"
+        smtpmail-debug-info t
+        mail-signature "\n\n-- \n2 + 2 = 5, for very large values of 2.\n"
+        mail-default-headers "CC: \n"
+        send-mail-function 'smtpmail-send-it
+        )
+
+  ;; shortcuts for tramp
+  ;; (my/add-to-list
+  ;;   'directory-abbrev-alist
+  ;;   '(("^/root" . "/su:/")
+  ;;      ("^/rebel" . "/ssh:arwen:www/cf.bodi/rebels21/")
+  ;;      ("^/strat" . "/ssh:arwen:www/cf.bodi/strat-dom/")))
+
+  (defconst my/loaded-files-at-startup
+    (list
+     "~/dev/brchess/Makefile"
+     "~/dev/tools/c/Makefile"
+     "~/org/boot-disk.org"
+     "~/org/beaglebone-buster-setup.org"
+     ;;"~/dev/www/cf.bodi/sql/coc.sql"
+     ;;"~/dev/www/cf.bodi/sql/coc-sql.org"
+      user-init-file
+      "~/org/emacs-cheatsheet.org"
+      ;;"~/dev/g910/g910-gkey-macro-support/lib/data_mappers/char_uinput_mapper.py"
+      "~/dev/advent-of-code/2022/Makefile"
+      "~/dev/www/com.raoult/devs/php/chess/list-pgn-games.php")
+      ;; "~/dev/eudyptula/ID")
+    "personal files always loaded at startup (no visible window).")
+
+  (let ((num 1))
+    (dolist
+      (filename my/loaded-files-at-startup)
+      (if (file-exists-p filename)
+        (progn
+          ;; set variable "my/buffer-1" to buffer returned by find-file
+          (set
+            (intern (concat "my/buffer-" (number-to-string num)))
+            (find-file-noselect filename nil nil nil))
+          (message "file: [%s] loaded." filename))
+        (message "cannot load file: [%s]." filename))
+        (cl-incf num)))
+
+  ;; set windows for current work buffers
+  (when (boundp 'my/graphic-loaded)
+    (set-window-buffer my/main-window my/buffer-1)
+    (set-window-buffer my/upper-window "*Messages*")
+    (set-window-buffer my/below-window my/buffer-2))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Coc sync
+  ;; mysql CoC connection (dev)
+  ;;(defun my/connect-coc ()
+    ;;(interactive)
+    ;;(my/sql-connect-preset 'coc))
+
+  (defun my/connect-coc ()
+    (interactive)
+    (sql-connect "coc"))
+
+  ;; sync from/to idril
+  (defun my/coc-get-db ()
+    "get last coc db from arwen"
+    (interactive)
+    ;; force run on local machine when in tramp buffer
+    (with-current-buffer (get-buffer "*scratch*")
+      (async-shell-command "sync-coc-db-from-idril.sh")))
+  (defun my/sync-www ()
+    "sync www to arwen - dry run"
+    (interactive)
+    (with-current-buffer (get-buffer "*scratch*")
+      (async-shell-command "sync-www-to-idril.sh")))
+  (defun my/sync-www-doit ()
+    "sync www to arwen"
+    (interactive)
+    (with-current-buffer (get-buffer "*scratch*")
+      (async-shell-command "sync-www-to-idril.sh -d")))
+
+  (setq org-publish-project-alist
+        '(("org"
+           :base-directory "~/org"
+           :base-extension "org"
+           :publishing-directory "~/dev/www/cf.bodi/org"
+           :recursive t
+           :publishing-function org-html-publish-to-html
+           ;;:headline-levels 4
+           ;;:section-numbers nil
+           ;;:html-head nil
+           :html-head-include-default-style nil
+           :html-head-include-scripts nil
+           ;; :html-preamble my-blog-header
+           ;;:html-postamble my-blog-footer
+           )
+          ("static"
+           :base-directory "~/org/"
+           :base-extension "css\\|js\\|png\\|jpg\\|gif\\|pdf\\|mp3\\|ogg\\|swf"
+           :publishing-directory "~/dev/www/cf.bodi/org/"
+           :recursive t
+           :publishing-function org-publish-attachment)
+
+        ;; Define any other projects here...
+        ))
+
+  (global-set-key (kbd "s-c c c") 'my/connect-coc)
+  (global-set-key (kbd "s-c c g") 'my/coc-get-db)
+  (global-set-key (kbd "s-c c s") 'my/sync-www)
+  (global-set-key (kbd "s-c c w") 'my/sync-www-doit))
+
+;; (Define-key my/keys-mode-map
+;;   (kbd "s-c c g") 'my/coc-gewt-db)
+;; (define-key my/keys-mode-map
+;;   (kbd "s-c c s") 'my/coc-sync-www)
+
+
+
+;; (set-window-buffer current-buffer (get-buffer "*messages*"))))
+;; (set-window-buffer "*messages*")
+
+;; Local Variables:
+;; flycheck-disabled-checkers: (emacs-lisp-checkdoc)
+;; End:

config/home/.emacs.d/term.el

@@ -0,0 +1,9 @@
+;; ~/.emacs.d/term.el
+;;
+;; emacs configuration - this file will be loaded only in terminal mode
+;;
+;; br, 2010-2018
+
+;;(print "loading term.el")
+
+