brlib repo creation

This commit is contained in:
2023-12-24 18:17:38 +01:00
parent e794bdf9c4
commit f9318ce49b
34 changed files with 0 additions and 0 deletions

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/* 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 */

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/* 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));
}

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/* 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 */

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#include <stdio.h>
#include "hash.h"
int main()
{
printf("foo\n");
return 1;
}

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// 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);
}

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/* 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 */

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#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 */

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/*
* 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;
}

259
todo/xxhash.h Normal file
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/*
* 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 */