pv.h (empty)

- hist.c: add hist_next() - get next entry in history
- state_t: remove plycount, clock_50 -> ply50, add phase, repcount
- pos_t: add plycount, plyroot
- state_t moved to chessdefs.h
- perft-test: split perft from do_perft (todo for perft_alt)
- position.c: add pos_repcount()
- search.c: add is_draw()
- uci: set root position (after moves), adjust history moves repcount

Makefile

@@ -39,7 +39,9 @@ OBJ       := $(addprefix $(OBJDIR)/,$(SRC_FN:.c=.o))
 TSTSRC    := $(wildcard $(TSTDIR)/*.c)
 
 LIB       := br_$(shell uname -m)                           # library name
-LIBS      := $(strip -l$(LIB))
+LIB       := $(strip $(LIB))
+LIBFILE   := ${BRLIBDIR}/lib$(strip ${LIB}).a
+LIBS      := $(addprefix -l,$(strip $(LIB)))
 
 DEP_FN    := $(SRC_FN)
 DEP       := $(addprefix $(DEPDIR)/,$(DEP_FN:.c=.d))
@@ -102,7 +104,7 @@ endif
 # if no version, use last commit and date.
 # else, if last commit != last tag commit, add commit and date to version number
 ifeq ($(VERSION),)
-  VERSION := $(build)-$(COMMIT)-$(DATE)
+  VERSION := $(build)-git.$(COMMIT)-$(DATE)
 else ifneq ($(COMMIT), $(TAG_COMMIT))
   VERSION := $(VERSION)-next-$(build)-$(COMMIT)-$(DATE)
 endif
@@ -124,18 +126,18 @@ else # ifeq ($(build),dev)
         #        fen.c
         #CPPFLAGS  += -DDEBUG_FEN                           # FEN decoding
         #        hash / TT
-        #CPPFLAGS  += -DZOBRIST_VERIFY                      # double chk zobrist
+        #CPPFLAGS  += -DZOBRIST_VERIFY                      # incr. zobrist check
         #CPPFLAGS  += -DPERFT_MOVE_HISTORY                  # perft, keep prev moves
         #        attack.c
         #CPPFLAGS  += -DDEBUG_ATTACK_ATTACKERS              # sq_attackers
         #CPPFLAGS  += -DDEBUG_ATTACK_PINNERS                # sq_pinners details
         #        eval.c eval-simple.c
-        CPPFLAGS  += -DDEBUG_EVAL                           # eval
+        CPPFLAGS  += -DDEBUG_EVAL                          # eval
+        CPPFLAGS  += -DPHASE_VERIFY                        # incr. phase check
 
         #        old unused flags
         #CPPFLAGS  += -DDEBUG_POS                           # position.c
         #CPPFLAGS  += -DDEBUG_MOVE                          # move generation
-        #CPPFLAGS  += -DDEBUG_EVAL                          # eval functions
 endif
 
 # remove extraneous spaces (due to spaces before comments)
@@ -345,6 +347,7 @@ brlib:
 	$(info calling with build=$(build))
 	$(MAKE) -e -C $(BRLIB) lib-static
 unexport build
+
 ##################################### brchess binaries
 .PHONY: targets cleanbin cleanbindir
 
@@ -356,9 +359,9 @@ cleanbin:
 cleanbindir:
 	$(call rmdir,$(BINDIR),binaries)
 
-$(TARGET): libs $(OBJ) | $(BINDIR)
+$(TARGET): $(LIBFILE) $(OBJ) | $(BINDIR) libs
 	@echo linking $@.
-	$(CC) $(LDFLAGS) $(OBJ) $(LIBS) -o $@
+	$(CC) $(ALL_LDFLAGS) $(OBJ) -o $@
 
 ##################################### pre-processed (.i) and assembler (.s) output
 .PHONY: cleanasmcpp
@@ -415,12 +418,13 @@ TEST          += movedo-test perft-test tt-test
 
 PIECE_OBJS    := piece.o
 FEN_OBJS      := $(PIECE_OBJS) fen.o position.o bitboard.o board.o \
-	hq.o attack.o hash.o init.o misc.o alloc.o move.o eval-defs.o
+	hq.o attack.o hash.o init.o util.o alloc.o move.o \
+	eval.o eval-defs.o eval-simple.o hist.o
 BB_OBJS       := $(FEN_OBJS)
 MOVEGEN_OBJS  := $(BB_OBJS) move-gen.o
 ATTACK_OBJS   := $(MOVEGEN_OBJS)
 MOVEDO_OBJS   := $(ATTACK_OBJS) move-do.o
-PERFT_OBJS    := $(MOVEDO_OBJS) search.o
+PERFT_OBJS    := $(MOVEDO_OBJS) perft.o
 TT_OBJS       := $(MOVEDO_OBJS)
 
 TEST          := $(addprefix $(BINDIR)/,$(TEST))
@@ -490,6 +494,7 @@ wtf:
 	@#echo LIBSRC=$(LIBSRC)
 
 zob:
+	echo $(LIBFILE)
 	@#$(CC) $(LDFLAGS) $(CPPFLAGS) $(CFLAGS) $< $(LIBS) src/util.c -o util
 
 ##################################### End of multi-targets

scripts/fetch-all.sh

@@ -29,6 +29,9 @@ readarray -t orig_b  < <(git for-each-ref --format='%(refname:short)' \
 # bugs:
 #  - We only check local branch existence, not tracking information correctness.
 #  - What about sub-branches ? Like remote/a and remote/a/b not being tracked ?
+#for i in `git branch -a | grep remote | grep -v HEAD | grep -v master`; do
+#    git branch --track ${i#remotes/origin/} $i
+#done
 for remote_b in "${orig_b[@]}"; do
     short=${remote_b#"$origin"/};
     # OR (??): short=${remote_b##*/}

src/brchess.c

@@ -13,9 +13,6 @@
 
 
 #include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <ctype.h>
 #include <unistd.h>
 
 #include <brlib.h>
@@ -40,10 +37,10 @@ int main(int ac, char **av)
     pos_t *pos;
     int opt;
 
+    printf("brchess " VERSION "\n");
     init_all();
     pos = pos_new();
-    hist_link(pos);
-    printf("\nWelcome to brchess " VERSION "\nEngine ready.\n");
+    printf("Engine ready.\n");
 
     // size_t len = 0;
     // char *str = NULL;

src/chessdefs.h

@@ -85,9 +85,9 @@ typedef struct __movelist_s movelist_t;
 
 /* basic types
  */
-
 typedef u64 bitboard_t;
 typedef s16 eval_t;
+typedef s8 phase_t;
 
 /* forward enum definition is impossible in C11.
  * To simplify cross-dependancies, all important enum are moved here.
@@ -142,42 +142,6 @@ typedef u8 dir_t;
 #define sq_upwest(up)     ((up) - 1)
 #define sq_upeast(up)     ((up) + 1)
 
-#include <time.h>
-
-typedef struct mclock {
-    clockid_t clocktype;
-    ulong elapsed_l;
-    double elapsed_f;
-    struct timespec start;
-} mclock_t;
-
-#define CLOCK_WALL    CLOCK_REALTIME
-#define CLOCK_SYSTEM  CLOCK_MONOTONIC_RAW
-#define CLOCK_PROCESS CLOCK_PROCESS_CPUTIME_ID
-#define CLOCK_THREAD  CLOCK_THREAD_CPUTIME_ID
-
-/**
- * CLOCK_DEFINE - define a clock type.
- * @name: clock name
- * @type: clock type
- *
- * This macro is equivalent to:
- *   mclock_t name;
- *   clock_init(&name, type);
- */
-#define CLOCK_DEFINE(name, type) struct mclock name = { .clocktype = type }
-
-void clock_init(mclock_t *clock, clockid_t type);
-void clock_start(mclock_t *clock);
-s64 clock_elapsed_μs(mclock_t *clock);
-s64 clock_elapsed_ms(mclock_t *clock);
-double clock_elapsed_sec(mclock_t *clock);
-
-#define RAND_SEED_DEFAULT U64(0xb0d1ccea)
-
-void rand_init(u64 seed);
-u64 rand64(void);
-
 void init_all(void);
 
 #endif  /* _CHESSDEFS_H */

src/eval-defs.c

@@ -1,4 +1,4 @@
-/* eval-values.c - eval static definitions.
+/* eval-values.c - eval parameters
  *
  * Copyright (C) 2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -18,9 +18,74 @@
 #include "position.h"
 #include "piece.h"
 #include "eval-defs.h"
+#include "util.h"
 //#include "eval-simple.h"
 //#include "eval.h"
 
+phase_t piece_phase[PIECE_TYPE_NB] = {
+    0, P_PHASE, N_PHASE, B_PHASE, R_PHASE, Q_PHASE, 0
+};
+
+/* eval parameters definition. */
+static const struct ev_params ev_param_def [EV_PARAMS_NB] = {
+    /*                type      setable def   min    max  name */
+    [WT_MAT]  =     { PAR_SPN,  true,   100,    0,   400, "material weight" },
+    [WT_PST]  =     { PAR_SPN,  true,   100,    0,   400, "pst weight" },
+    [TST_CHK] =     { PAR_CHK,  true,     1,    0,     0, "test check" },
+    [TST_SPN] =     { PAR_BTN,  true,     0,    0,     0, "test button" },
+
+};
+
+void param_init()
+{
+    for (int i = 0; i < EV_PARAMS_NB; ++i)
+        parameters[i] = ev_param_def[i].init;
+}
+
+int param_find_name(char *name)
+{
+    for (int i = 0; i < EV_PARAMS_NB; ++i)
+        if (str_eq_case(ev_param_def[i].name, name))
+            return i;
+    return -1;
+}
+char *param_name(const int num)
+{
+    return ev_param_def[num].name;
+}
+
+eval_t param_default(const int num)
+{
+    return ev_param_def[num].init;
+}
+eval_t param_min(const int num)
+{
+    return ev_param_def[num].min;
+}
+eval_t param_max(const int num)
+{
+    return ev_param_def[num].max;
+}
+bool param_setable(const int num)
+{
+    return ev_param_def[num].setable;
+}
+int param_type(const int num)
+{
+    return ev_param_def[num].type;
+}
+
+/* parameters in use */
+eval_t parameters[EV_PARAMS_NB];
+void param_set(int num, eval_t val)
+{
+    if (num >= 0 && num < EV_PARAMS_NB &&
+        val >= param_min(num) && val <= param_max(num)) {
+        parameters[num] = val;
+    }
+}
+
+
 /*
  * Piece-square tables. For easier reading, they are defined for black side:
  *
@@ -31,38 +96,46 @@
  *        A1 .... H1
  *      }
  */
-const struct pst pst_defs[] = {
-    {
+static const struct pst {
+    char *name;                                   /* one word only, no spaces */
+    int val[PIECE_TYPE_NB][PHASE_NB][SQUARE_NB];  /* MG then EG */
+} pst_defs[PST_NB] = {
+    [PST_ROFCHADE] = {
         /*
          * rofchade:
          * https://www.talkchess.com/forum3/viewtopic.php?f=2&t=68311&start=19
          */
-        "rofchade",
+        "Rofchade",
         {
+            /* A8 ..... H8
+             * ...........
+             * A1 ..... H1
+             */
             [PAWN] = {
                 {                                 /* midgame */
-                    0,   0,   0,   0,   0,   0,  0,   0,
-                    98, 134,  61,  95,  68, 126, 34, -11,
-                    -6,   7,  26,  31,  65,  56, 25, -20,
+                    + 0,   0,   0,   0,   0,   0,  0,   0,
+                    +98, 134,  61,  95,  68, 126, 34, -11,
+                    - 6,   7,  26,  31,  65,  56, 25, -20,
                     -14,  13,   6,  21,  23,  12, 17, -23,
                     -27,  -2,  -5,  12,  17,   6, 10, -25,
                     -26,  -4,  -4, -10,   3,   3, 33, -12,
                     -35,  -1, -20, -23, -15,  24, 38, -22,
-                    0,   0,   0,   0,   0,   0,  0,   0,
+                    + 0,   0,   0,   0,   0,   0,  0,   0,
                 },
                 {                                 /* endgame */
-                    0,   0,   0,   0,   0,   0,   0,   0,
+                    + 0,   0,   0,   0,   0,   0,   0,   0,
                     178, 173, 158, 134, 147, 132, 165, 187,
-                    94, 100,  85,  67,  56,  53,  82,  84,
-                    32,  24,  13,   5,  -2,   4,  17,  17,
-                    13,   9,  -3,  -7,  -7,  -8,   3,  -1,
-                    4,   7,  -6,   1,   0,  -5,  -1,  -8,
-                    13,   8,   8,  10,  13,   0,   2,  -7,
-                    0,   0,   0,   0,   0,   0,   0,   0,
+                    +94, 100,  85,  67,  56,  53,  82,  84,
+                    +32,  24,  13,   5,  -2,   4,  17,  17,
+                    +13,   9,  -3,  -7,  -7,  -8,   3,  -1,
+                    + 4,   7,  -6,   1,   0,  -5,  -1,  -8,
+                    +13,   8,   8,  10,  13,   0,   2,  -7,
+                    + 0,   0,   0,   0,   0,   0,   0,   0,
                 }
             },
             [KNIGHT] = {
-                {                                 /* midgame */
+                {
+                    /* midgame */
                     -167, -89, -34, -49,  61, -97, -15, -107,
                     -73, -41,  72,  36,  23,  62,   7,  -17,
                     -47,  60,  37,  65,  84, 129,  73,   44,
@@ -88,18 +161,18 @@ const struct pst pst_defs[] = {
                     -29,  4, -82, -37, -25, -42,   7,  -8,
                     -26, 16, -18, -13,  30,  59,  18, -47,
                     -16, 37,  43,  40,  35,  50,  37,  -2,
-                     -4,  5,  19,  50,  37,  37,   7,  -2,
-                     -6, 13,  13,  26,  34,  12,  10,   4,
-                      0, 15,  15,  15,  14,  27,  18,  10,
-                      4, 15,  16,   0,   7,  21,  33,   1,
+                    - 4,  5,  19,  50,  37,  37,   7,  -2,
+                    - 6, 13,  13,  26,  34,  12,  10,   4,
+                    + 0, 15,  15,  15,  14,  27,  18,  10,
+                    + 4, 15,  16,   0,   7,  21,  33,   1,
                     -33, -3, -14, -21, -13, -12, -39, -21,
                 },
                 {                                 /* endgame */
                     -14, -21, -11,  -8, -7,  -9, -17, -24,
-                     -8,  -4,   7, -12, -3, -13,  -4, -14,
-                      2,  -8,   0,  -1, -2,   6,   0,   4,
-                     -3,   9,  12,   9, 14,  10,   3,   2,
-                     -6,   3,  13,  19,  7,  10,  -3,  -9,
+                    - 8,  -4,   7, -12, -3, -13,  -4, -14,
+                    + 2,  -8,   0,  -1, -2,   6,   0,   4,
+                    - 3,   9,  12,   9, 14,  10,   3,   2,
+                    - 6,   3,  13,  19,  7,  10,  -3,  -9,
                     -12,  -3,   8,  10, 13,   3,  -7, -15,
                     -14, -18,  -7,  -1,  4,  -9, -15, -27,
                     -23,  -9, -23,  -5, -9, -16,  -5, -17,
@@ -107,9 +180,9 @@ const struct pst pst_defs[] = {
             },
             [ROOK] = {
                 {                                 /* midgame */
-                    32,  42,  32,  51, 63,  9,  31,  43,
-                    27,  32,  58,  62, 80, 67,  26,  44,
-                    -5,  19,  26,  36, 17, 45,  61,  16,
+                    +32,  42,  32,  51, 63,  9,  31,  43,
+                    +27,  32,  58,  62, 80, 67,  26,  44,
+                    - 5,  19,  26,  36, 17, 45,  61,  16,
                     -24, -11,   7,  26, 24, 35,  -8, -20,
                     -36, -26, -12,  -1,  9, -7,   6, -23,
                     -45, -25, -16, -17,  3,  0,  -5, -33,
@@ -119,9 +192,9 @@ const struct pst pst_defs[] = {
                 {                                 /* endgame */
                     13, 10, 18, 15, 12,  12,   8,   5,
                     11, 13, 13, 11, -3,   3,   8,   3,
-                    7,  7,  7,  5,  4,  -3,  -5,  -3,
-                    4,  3, 13,  1,  2,   1,  -1,   2,
-                    3,  5,  8,  4, -5,  -6,  -8, -11,
+                    +7,  7,  7,  5,  4,  -3,  -5,  -3,
+                    +4,  3, 13,  1,  2,   1,  -1,   2,
+                    +3,  5,  8,  4, -5,  -6,  -8, -11,
                     -4,  0, -5, -1, -7, -12,  -8, -16,
                     -6, -6,  0,  2, -9,  -9, -11,  -3,
                     -9,  2,  3, -1, -5, -13,   4, -20,
@@ -133,16 +206,16 @@ const struct pst pst_defs[] = {
                     -24, -39,  -5,   1, -16,  57,  28,  54,
                     -13, -17,   7,   8,  29,  56,  47,  57,
                     -27, -27, -16, -16,  -1,  17,  -2,   1,
-                    -9, -26,  -9, -10,  -2,  -4,   3,  -3,
+                    - 9, -26,  -9, -10,  -2,  -4,   3,  -3,
                     -14,   2, -11,  -2,  -5,   2,  14,   5,
                     -35,  -8,  11,   2,   8,  15,  -3,   1,
-                    -1, -18,  -9,  10, -15, -25, -31, -50,
+                    - 1, -18,  -9,  10, -15, -25, -31, -50,
                 },
                 {                                 /* endgame */
-                    -9,  22,  22,  27,  27,  19,  10,  20,
+                    - 9,  22,  22,  27,  27,  19,  10,  20,
                     -17,  20,  32,  41,  58,  25,  30,   0,
                     -20,   6,   9,  49,  47,  35,  19,   9,
-                    3,  22,  24,  45,  57,  40,  57,  36,
+                    + 3,  22,  24,  45,  57,  40,  57,  36,
                     -18,  28,  19,  47,  31,  34,  39,  23,
                     -16, -27,  15,   6,   9,  17,  10,   5,
                     -22, -23, -30, -16, -16, -23, -36, -32,
@@ -152,19 +225,19 @@ const struct pst pst_defs[] = {
             [KING] = {                            /* midgame */
                 {
                     -65,  23,  16, -15, -56, -34,   2,  13,
-                    29,  -1, -20,  -7,  -8,  -4, -38, -29,
-                    -9,  24,   2, -16, -20,   6,  22, -22,
+                    +29,  -1, -20,  -7,  -8,  -4, -38, -29,
+                    - 9,  24,   2, -16, -20,   6,  22, -22,
                     -17, -20, -12, -27, -30, -25, -14, -36,
                     -49,  -1, -27, -39, -46, -44, -33, -51,
                     -14, -14, -22, -46, -44, -30, -15, -27,
-                    1,   7,  -8, -64, -43, -16,   9,   8,
+                    + 1,   7,  -8, -64, -43, -16,   9,   8,
                     -15,  36,  12, -54,   8, -28,  24,  14,
                 },
                 {                                 /* endgame */
                     -74, -35, -18, -18, -11,  15,   4, -17,
                     -12,  17,  14,  17,  17,  38,  23,  11,
-                    10,  17,  23,  15,  20,  45,  44,  13,
-                    -8,  22,  24,  27,  26,  33,  26,   3,
+                    +10,  17,  23,  15,  20,  45,  44,  13,
+                    - 8,  22,  24,  27,  26,  33,  26,   3,
                     -18,  -4,  21,  24,  27,  23,   9, -11,
                     -19,  -3,  11,  21,  23,  16,   7,  -9,
                     -27, -11,   4,  13,  14,   4,  -5, -17,
@@ -172,35 +245,41 @@ const struct pst pst_defs[] = {
                 }
             }
         }
-    },                                            /* CPW */
-    {
+    },                                            /* rofchade end */
+
+    [PST_CPW] = {
         /*
          * CPW:
          * https://www.chessprogramming.org/Simplified_Evaluation_Function
          * Note: ≠ https://github.com/nescitus/cpw-engine
          */
-        "cpw",
+        "CPW",
         {
+            /* A8 ..... H8
+             * ...........
+             * A1 ..... H1
+             */
             [PAWN] = {
-                {                                 /* midgame */
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                { /* H1                                 H8 */
+                    /* midgame */
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                     50, 50,  50,  50,  50,  50, 50, 50,
                     10, 10,  20,  30,  30,  20, 10, 10,
-                    5,  5,  10,  25,  25,  10,  5,  5,
-                    0,  0,   0,  20,  20,   0,  0,  0,
-                    5, -5, -10,   0,   0, -10, -5,  5,
-                    5, 10,  10, -20, -20,  10, 10,  5,
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +5,  5,  10,  25,  25,  10,  5,  5,
+                    +0,  0,   0,  20,  20,   0,  0,  0,
+                    +5, -5, -10,   0,   0, -10, -5,  5,
+                    +5, 10,  10, -20, -20,  10, 10,  5,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                 },
                 {                                 /* endgame */
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                     50, 50,  50,  50,  50,  50, 50, 50,
                     10, 10,  20,  30,  30,  20, 10, 10,
-                    5,  5,  10,  25,  25,  10,  5,  5,
-                    0,  0,   0,  20,  20,   0,  0,  0,
-                    5, -5, -10,   0,   0, -10, -5,  5,
-                    5, 10,  10, -20, -20,  10, 10,  5,
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +5,  5,  10,  25,  25,  10,  5,  5,
+                    +0,  0,   0,  20,  20,   0,  0,  0,
+                    +5, -5, -10,   0,   0, -10, -5,  5,
+                    +5, 10,  10, -20, -20,  10, 10,  5,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                 },
             },
             [KNIGHT] = {
@@ -249,24 +328,24 @@ const struct pst pst_defs[] = {
             },
             [ROOK] = {
                 {                                 /* midgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
                 {                                 /* endgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
             },
             [QUEEN] = {
@@ -274,8 +353,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -10,   0,   5,  5,  5,   5,   0, -10,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
+                    - 5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   5,   5,  5,  5,   5,   0, -10,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -284,8 +363,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -10,   0,   5,  5,  5,   5,   0, -10,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
+                    - 5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   5,   5,  5,  5,   5,   0, -10,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -299,8 +378,8 @@ const struct pst pst_defs[] = {
                     -30, -40, -40, -50, -50, -40, -40, -30,
                     -20, -30, -30, -40, -40, -30, -30, -20,
                     -10, -20, -20, -20, -20, -20, -20, -10,
-                    20,  20,   0,   0,   0,   0,  20,  20,
-                    20,  30,  10,   0,   0,  10,  30,  20,
+                    +20,  20,   0,   0,   0,   0,  20,  20,
+                    +20,  30,  10,   0,   0,  10,  30,  20,
                 },
                 {                                 /* endgame */
                     -50, -40, -30, -20, -20, -30, -40, -50,
@@ -314,14 +393,19 @@ const struct pst pst_defs[] = {
                 }
             }
         }
-    },                                            /* CPW */
-    {
+    },                                            /* CPW end */
+
+    [PST_SJENG] = {
         /*
          * sjeng: https://github.com/gcp/sjeng
          * Rook and Queen from CPW.
          */
-        "sjeng",
+        "Sjeng",
         {
+            /* A8 ..... H8
+             * ...........
+             * A1 ..... H1
+             */
             [PAWN] = {
                 {                                 /* midgame */
                     0,  0,  0,  0,  0,  0,  0, 0,
@@ -390,24 +474,24 @@ const struct pst pst_defs[] = {
             },
             [ROOK] = {
                 {                                 /* midgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
                 {                                 /* endgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
             },
             [QUEEN] = {
@@ -415,8 +499,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -10,   5,   5,  5,  5,   5,   0, -10,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
+                    -05,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   0,   5,  5,  5,   5,   0, -10,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -425,8 +509,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -10,   5,   5,  5,  5,   5,   0, -10,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
+                    - 5,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   0,   5,  5,  5,   5,   0, -10,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -438,88 +522,78 @@ const struct pst pst_defs[] = {
                     -34, -34, -55, -55, -55, -55, -34, -34,
                     -21, -21, -34, -34, -34, -34, -21, -21,
                     -13, -13, -21, -21, -21, -21, -13, -13,
-                    -8,  -8, -13, -13, -13, -13,  -8,  -8,
-                    -5,  -5,  -8,  -8,  -8,  -8,  -5,  -5,
-                    -3,  -5,  -6,  -6,  -6,  -6,  -5,  -3,
-                    2,  14,   0,   0,   0,   9,  14,   2,
+                    - 8,  -8, -13, -13, -13, -13,  -8,  -8,
+                    - 5,  -5,  -8,  -8,  -8,  -8,  -5,  -5,
+                    - 3,  -5,  -6,  -6,  -6,  -6,  -5,  -3,
+                    + 2,  14,   0,   0,   0,   9,  14,   2,
                 },
                 {                                 /* endgame */
                     -5, -3, -1,  0,  0, -1, -3, -5,
                     -3, 10, 10, 10, 10, 10, 10, -3,
                     -1, 10, 25, 25, 25, 25, 10, -1,
-                    0, 10, 25, 30, 30, 25, 10,  0,
-                    0, 10, 25, 30, 30, 25, 10,  0,
+                    +0, 10, 25, 30, 30, 25, 10,  0,
+                    +0, 10, 25, 30, 30, 25, 10,  0,
                     -1, 10, 25, 25, 25, 25, 10, -1,
                     -3, 10, 10, 10, 10, 10, 10, -3,
                     -5, -3, -1,  0,  0, -1, -3, -5,
                 }
             }
         },
-    },                                            /* sjeng */
+    },                                            /* sjeng end */
 };
 
-const int nb_pc_sq = ARRAY_SIZE(pst_defs);        /* # of predefined pc_sq tables */
-int pst_current = 0;
-int pst_mg[COLOR_NB][PT_NB][SQUARE_NB];
-int pst_eg[COLOR_NB][PT_NB][SQUARE_NB];
+int pst_current = PST_DEFAULT;
+eval_t pst_mg[COLOR_NB][PT_NB][SQUARE_NB];
+eval_t pst_eg[COLOR_NB][PT_NB][SQUARE_NB];
 
-/* phase calculation from Fruit:
- * https://github.com/Warpten/Fruit-2.1
-*/
-
-/**
- * calc_phase - calculate position phase
- * @pos: &position
- *
- * This function should be calculated when a new position is setup, or as
- * a verification of an incremental one.
- * phase is clamped between 0 (opening) and 24 (ending).
- *
- * @return:
- */
-s16 calc_phase(pos_t *pos)
+void pst_set(char *str)
 {
-    int phase = ALL_PHASE;
-    phase -= P_PHASE * popcount64(pos->bb[WHITE][PAWN] | pos->bb[BLACK][PAWN]);
-    phase -= N_PHASE * popcount64(pos->bb[WHITE][KNIGHT] | pos->bb[BLACK][KNIGHT]);
-    phase -= B_PHASE * popcount64(pos->bb[WHITE][BISHOP] | pos->bb[BLACK][BISHOP]);
-    phase -= R_PHASE * popcount64(pos->bb[WHITE][ROOK] | pos->bb[BLACK][ROOK]);
-    phase -= Q_PHASE * popcount64(pos->bb[WHITE][QUEEN] | pos->bb[BLACK][QUEEN]);
-
-    phase = clamp(phase, 0, ALL_PHASE);
-#   ifdef DEBUG_EVAL
-    printf("calc phase:%d\n", phase);
-#   endif
-    return phase;
+    pst_init(pst_find(str));
 }
 
-static int pst_find(char *str)
+int pst_find(char *str)
 {
-    for (int i = 0; i < nb_pc_sq; ++i)
-        if (!strcmp(pst_defs[i].name, str))
+    for (int i = 0; i < PST_NB; ++i) {
+        if (str_eq_case(pst_defs[i].name, str))
             return i;
+    }
     return -1;
 }
 
-void pst_init(char *name)
+void pst_init(int set)
 {
-    const struct pst *cur;
-    int set = pst_find(name);
-#   ifdef DEBUG_EVAL
-    printf("initializing piece-square tables `%s`(%d)\n", name, set);
-#   endif
-    if (set < 0)
+    const struct pst *pst;
+
+    if (warn(set < 0 || set >= PST_NB, "wrong PST, defaulting to zero."))
         set = 0;
 
-    cur = pst_defs + set;
-    pst_current = set;
-    for (piece_type_t pt = PAWN; pt < PT_NB; ++pt) {
-        for (square_t sq = 0; sq < SQUARE_NB; ++sq) {
-            pst_mg[BLACK][pt][sq] = cur->val[MIDGAME][pt][sq];
-            pst_mg[WHITE][pt][sq] = cur->val[MIDGAME][pt][FLIP_V(sq)];
+#   ifdef DEBUG_EVAL2
+    printf("initializing piece-square tables %d ('%s')\n", set, pst_defs[set].name);
+#   endif
 
-            pst_eg[BLACK][pt][sq] = cur->val[ENDGAME][pt][sq];
-            pst_eg[WHITE][pt][sq] = cur->val[ENDGAME][pt][FLIP_V(sq)];
+    pst = pst_defs + set;
+    pst_current = set;
+    int wmat = param(WT_MAT);
+    int wpst = param(WT_PST);
+    for (piece_type_t pt = PAWN; pt < PT_NB; ++pt) {
+        eval_t mid_pc = piece_midval(pt);
+        eval_t end_pc = piece_endval(pt);
+        for (square_t sq = 0; sq < SQUARE_NB; ++sq) {
+            eval_t mid_pst = pst->val[MIDGAME][pt][sq];
+            eval_t end_pst = pst->val[ENDGAME][pt][sq];
+
+            pst_mg[BLACK][pt][sq] = (mid_pc * wmat + mid_pst * wpst) / 100;
+            pst_eg[BLACK][pt][sq] = (end_pc * wmat + end_pst * wpst) / 100;
+
+            pst_mg[WHITE][pt][FLIP_V(sq)] =  pst_mg[BLACK][pt][sq];
+            pst_eg[WHITE][pt][FLIP_V(sq)] =  pst_eg[BLACK][pt][sq];
         }
     }
 }
+
+char *pst_name(int i)
+{
+    if (i >= 0 && i < PST_NB)
+        return pst_defs[i].name;
+    return "undef";
+}

src/eval-defs.h

@@ -0,0 +1,125 @@
+/* eval-defs.h - eval parameters
+ *
+ * Copyright (C) 2024 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 EVAL_DEFS_H
+#define EVAL_DEFS_H
+
+#include "chessdefs.h"
+#include "piece.h"
+#include "eval.h"
+
+/* game phases
+ */
+enum {
+    MIDGAME,
+    ENDGAME,
+    PHASE_NB
+};
+
+/* pieces weight in phase calculation.
+ */
+enum {
+    P_PHASE = 0,
+    N_PHASE = 1,
+    B_PHASE = 1,
+    R_PHASE = 2,
+    Q_PHASE = 4,
+    ALL_PHASE = P_PHASE*16 + N_PHASE*4 + B_PHASE*4 + R_PHASE*4 + Q_PHASE*2
+};
+extern phase_t piece_phase[PIECE_TYPE_NB];
+
+static inline phase_t pt_phase(piece_type_t pt)
+{
+    return piece_phase[pt];
+}
+
+/* max pieces eval is 9*QUEEN_VALUE + 2*ROOK_VALUE + 2*BISHOP_VALUE
+ * + 2*KNIGHT_VALUE which is (for a pawn valued at 100) well less than 15,000.
+ */
+#define EVAL_MAX     (SHRT_MAX)                   /* 32767 */
+#define EVAL_MIN     (-EVAL_MAX)
+#define EVAL_DRAW    0
+#define EVAL_INV     EVAL_MIN
+
+#define EVAL_MATE    30000
+
+/* engine parameters */
+enum {
+    WT_MAT,
+    WT_PST,
+
+    TST_SPN,
+    TST_CHK,
+
+    EV_PARAMS_NB
+};
+
+enum {
+    PAR_CHK,
+    PAR_SPN,
+    PAR_BTN,
+    PAR_STR,
+};
+
+/**
+ * ev_params - parameters definition
+ * @init: eval_t default value
+ * @min, @max: eval_t min and max values
+ * @type: variable type (PARAM_CHECK, etc...)
+ * @setable: bool setable (proposed in UCI options)
+ * @name: char * human readable name
+ */
+struct ev_params {
+    int type;
+    bool setable;                                 /* true: proposed in UCI options */
+    eval_t init, min, max;
+    char *name;
+};
+void param_init(void);
+int param_find_name(char *name);                  /* find parameter number by name */
+char *param_name(const int num);
+
+eval_t param_default(const int num);              /* get default param value */
+eval_t param_min(const int num);
+eval_t param_max(const int num);
+bool param_setable(const int num);
+int param_type(const int num);
+
+/* parameters in use */
+extern eval_t parameters[EV_PARAMS_NB];
+#define param(n) parameters[n]
+void param_set (int num, eval_t val);
+
+/* PST data */
+/**
+ * pst_defs - pre-defined piece-square tables.
+ */
+enum {
+    PST_ROFCHADE,
+    PST_CPW,
+    PST_SJENG,
+    PST_NB
+};
+
+#define PST_DEFAULT PST_CPW
+extern int pst_current;
+extern eval_t pst_mg[COLOR_NB][PT_NB][SQUARE_NB];
+extern eval_t pst_eg[COLOR_NB][PT_NB][SQUARE_NB];
+
+void pst_set(char *str);
+int pst_find(char *str);
+void pst_init(int pst);
+
+char *pst_name(int i);
+
+#endif  /* EVAL_DEFS_H */

src/eval-simple.c

@@ -48,19 +48,15 @@ eval_t eval_material(pos_t *pos)
  * eval_simple() - simple and fast position evaluation
  * @pos: &position to evaluate
  *
- * This function is normally used only during initialization,
- * or when changing phase (middlegame <--> endgame), as the eval
- * will be done incrementally when doing moves.
- *
  * @return: the @pos evaluation in centipawns
  */
 eval_t eval_simple(pos_t *pos)
 {
-    eval_t eval[2] = { 0, 0 };
+    eval_t eval[2] = { 0, 0 }, res;
     eval_t mg_eval[2], eg_eval[2];
-    //struct pc_sq = sq_ int (*gg)[6 + 2][64] = eg? pc_sq_eg: pc_sq_mg;
 
-    //pos->eval_simple_phase = ENDGAME;
+    int eg_weight = clamp((int) pos->phase, ALL_PHASE, 0);
+    int mg_weight = ALL_PHASE - pos->phase;
 
     for (color_t color = WHITE; color < COLOR_NB; ++color) {
         mg_eval[color] = 0;
@@ -70,7 +66,7 @@ eval_t eval_simple(pos_t *pos)
             while (bb) {
                 square_t sq = bb_next(&bb);
                 mg_eval[color] += pst_mg[color][pt][sq];
-                eg_eval[color] += pst_mg[color][pt][sq];
+                eg_eval[color] += pst_eg[color][pt][sq];
             }
 
 #           ifdef DEBUG_EVAL
@@ -80,10 +76,15 @@ eval_t eval_simple(pos_t *pos)
 
         }
     }
+    eval[WHITE] = mg_eval[WHITE] * mg_weight + eg_eval[WHITE] * eg_weight;
+    eval[BLACK] = mg_eval[BLACK] * mg_weight + eg_eval[BLACK] * eg_weight;
+    res = (eval[WHITE] - eval[BLACK]) / ALL_PHASE;
 #   ifdef DEBUG_EVAL
-    printf("phase:%d mg[WHITE]:%d mg[BLACK]:%d eg[WHITE]:%d eg[BLACK]:%d\n",
-           pos->phase, mg_eval[WHITE], mg_eval[BLACK], eg_eval[WHITE], eg_eval[BLACK]);
+    printf("phase:%d mg:%d/%d eg:%d/%d ev:%d/%d RES=%d\n",
+           pos->phase, mg_eval[WHITE], mg_eval[BLACK],
+           eg_eval[WHITE], eg_eval[BLACK],
+           eval[WHITE], eval[BLACK], res
+        );
 #   endif
-
-    return eval[WHITE] - eval[BLACK];
+    return res;
 }

src/eval.c

@@ -19,6 +19,91 @@
 #include "position.h"
 #include "eval.h"
 #include "eval-simple.h"
+#include "hist.h"
+
+/**
+ * calc_phase - calculate position phase
+ * @pos: &position
+ *
+ * This function should be calculated when a new position is setup, or as
+ * a verification of an incremental one.
+ * Note: phase is *not* clamped, to avoid update errors.
+ *
+ * @return: phase value
+ */
+phase_t calc_phase(pos_t *pos)
+{
+    int phase = ALL_PHASE;
+    for (piece_type_t pt = PAWN; pt < KING; ++pt)
+        phase -= piece_phase[pt] * popcount64(pos->bb[WHITE][pt] | pos->bb[BLACK][pt]);
+#   ifdef DEBUG_PHASE
+    printf("calc phase:%d\n", phase);
+#   endif
+    return phase;
+}
+
+/**
+ * phase_verify() - verify position phase.
+ * @pos: &position
+ *
+ * Verify that position phase is correct (a full recalculation is performed).
+ * This function is inactive if PHASE_VERIFY is not set.
+ *
+ * @return: True if phase key is OK, no return otherwise.
+ */
+#ifdef PHASE_VERIFY
+bool phase_verify(pos_t *pos)
+{
+    phase_t verif = calc_phase(pos);
+    if (pos->phase != verif) {
+        warn(true, "warn phase=%d verif=%d\n", pos->phase, verif);
+        hist_print(pos);
+        bug_on(pos->phase != verif);
+    }
+    return true;
+}
+#endif
+
+/**
+ * calc_phase - calculate position phase
+ * @pos: &position
+ *
+ * This function should be calculated when a new position is setup, or as
+ * a verification of an incremental one.
+ * phase is clamped between 0 (opening) and 24 (ending).
+ *
+ * @return:
+ */
+__unused static phase_t calc_phase2(pos_t *pos)
+{
+    int phase = ALL_PHASE;
+    phase -= P_PHASE * popcount64(pos->bb[WHITE][PAWN]   | pos->bb[BLACK][PAWN]);
+    phase -= N_PHASE * popcount64(pos->bb[WHITE][KNIGHT] | pos->bb[BLACK][KNIGHT]);
+    phase -= B_PHASE * popcount64(pos->bb[WHITE][BISHOP] | pos->bb[BLACK][BISHOP]);
+    phase -= R_PHASE * popcount64(pos->bb[WHITE][ROOK]   | pos->bb[BLACK][ROOK]);
+    phase -= Q_PHASE * popcount64(pos->bb[WHITE][QUEEN]  | pos->bb[BLACK][QUEEN]);
+
+    phase = max(phase, 0);
+#   ifdef DEBUG_EVAL
+    printf("calc phase:%d verif=%d\n", phase, calc_phase(pos));
+#   endif
+    return phase;
+}
+
+
+
+/*
+ * inline eval_t eval_mobility(pos_t *pos, bool color)
+ * {
+ *     return pos->mobility[color];
+ * }
+ *
+ *
+ * inline eval_t eval_square_control(pos_t *pos, bool color)
+ * {
+ *     return popcount64(pos->controlled[color]);
+ * }
+ */
 
 /*
  * inline eval_t eval_mobility(pos_t *pos, bool color)

src/eval.h

@@ -19,6 +19,13 @@
 #include "chessdefs.h"
 #include "eval-defs.h"
 
+phase_t calc_phase(pos_t *pos);
+#ifdef PHASE_VERIFY
+bool phase_verify(pos_t *pos);
+#else
+#define phase_verify(p) true
+#endif
+
 eval_t eval_mobility(pos_t *pos, bool color);
 eval_t eval_square_control(pos_t *pos, bool color);
 

src/fen.c

@@ -230,12 +230,12 @@ pos_t *fen2pos(pos_t *pos, const char *fen)
 
     /* 5) half moves since last capture or pawn move (50 moves rule)
      */
-    tmppos.clock_50 = 0;
+    tmppos.ply50 = 0;
     tmppos.plycount = 1;
     if (sscanf(cur, "%hd%n", &tmp, &consumed) != 1)
         goto end;                                 /* early end, ignore w/o err */
 
-    tmppos.clock_50 = tmp;
+    tmppos.ply50 = tmp;
     cur += consumed;
     SKIP_BLANK(cur);
 
@@ -350,7 +350,7 @@ char *pos2fen(const pos_t *pos, char *fen)
     /* 5) moves since last capture or pawn move (50 moves rule)
      * 6) current full move number, starting with 1
      */
-    sprintf(fen+cur, "%d %d", pos->clock_50,
+    sprintf(fen+cur, "%d %d", pos->ply50,
             1 + (pos->plycount - (pos->turn == BLACK)) / 2);
     return fen;
 }

src/hash.c

@@ -19,6 +19,7 @@
 #include <bug.h>
 
 #include "chessdefs.h"
+#include "util.h"
 #include "alloc.h"
 #include "position.h"
 #include "piece.h"
@@ -96,12 +97,11 @@ hkey_t zobrist_calc(pos_t *pos)
  * @pos: &position
  *
  * Verify that position Zobrist key matches a full Zobrist calculation.
- * This function cannot be called if ZOBRIST_VERIFY is not set.
+ * This function is inactive if ZOBRIST_VERIFY is not set.
  *
- * @return: True if Zobrist key is OK.
+ * @return: True if Zobrist key is OK, no return otherwise.
  */
 #ifdef ZOBRIST_VERIFY
-
 bool zobrist_verify(pos_t *pos)
 {
     hkey_t diff, key = zobrist_calc(pos);
@@ -266,10 +266,8 @@ hentry_t *tt_probe(hkey_t key)
     for (i = 0; i < ENTRIES_PER_BUCKET; ++i) {
         entry = bucket->entry + i;
         if (key == entry->key)
-            break;
+            return entry;
     }
-    if (i < ENTRIES_PER_BUCKET)
-        return entry;
     return NULL;
 }
 

src/hash.h

@@ -44,14 +44,16 @@ typedef u64 hkey_t;                               /* cannot use typedef for key_
  * 16 bytes in future, it should be updated to be exactly 32 bytes.
  */
 typedef struct {
-    hkey_t key;                                   /* zobrist */
+    hkey_t key;                                   /* position key */
     union {
         u64 data;
         struct {
-            u16 depth;                            /* ply in search */
-            s16 eval;
-            move_t move;
-            //u8 flags;                             /* maybe for locking, etc... */
+            s16 eval;                             /* 16: eval */
+            move_t move;                          /* 16: best move */
+            u8 depth;                             /*  8: search depth */
+            u8 gen8;                              /*  8: search generation */
+
+            //flags;                             /* maybe for locking, etc... */
             //u8 filler;
         };
     };

src/hist.c

@@ -37,6 +37,16 @@ void hist_init(void)
     hist.state[0].prev = &hist.state[0];
 }
 
+/**
+ * hist_next() - get next history slot.
+ *
+ * return: @state_t next history slot.
+ */
+state_t *hist_next(void)
+{
+    return hist.state + hist.nstates++;
+}
+
 /**
  * hist_push() - add a state to hist list
  * @st:   &state_t to add
@@ -134,9 +144,10 @@ void hist_static_print(void)
 
     printf("UCI state history: ");
     while (true) {
-        printf("%s(#%lx) ",
+        printf("%s(#%lx r=%d) ",
                move_to_str(movestr, st->move, 0),
-               hash_short(st->key));
+               hash_short(st->key),
+               st->repcount);
         if (st == HIST_START)
             break;
         st = hist_prev(st);
@@ -154,9 +165,10 @@ void hist_print(pos_t *pos)
     state_t *st = &pos->state;
     printf("position states history: ");
     while (true) {
-        printf("%s(#%lx) ",
+        printf("%s(#%lx r=%d) ",
                move_to_str(movestr, st->move, 0),
-               hash_short(st->key));
+               hash_short(st->key),
+               st->repcount);
         if (st == HIST_START)
             break;
         st = hist_prev(st);

src/hist.h

@@ -48,6 +48,7 @@ extern hist_t hist;
 #define HIST_START  (hist.state)
 
 void hist_init(void);
+state_t *hist_next(void);
 void hist_push(state_t *st); //, move_t *move);
 void hist_link(pos_t *pos);
 state_t *hist_pop(void);

src/init.c

@@ -16,7 +16,7 @@
 #include <locale.h>
 
 #include "chessdefs.h"
-
+#include "util.h"
 #include "bitboard.h"
 #include "hq.h"
 #include "eval-defs.h"
@@ -27,18 +27,23 @@
 
 void init_all(void)
 {
+    printff("initiazing system: ");
     /* line-buffered stdout */
-    printff("initiazing stdout buffering... ");
+    printff("stdout buffering... ");
     setlinebuf(stdout);
 
-    /* for printf() numeric thousands separator */
     printff("locale... ");
+    /* for printf() thousands separator */
     setlocale(LC_NUMERIC, "");
+    setlocale(LC_CTYPE, "C");
 
     /* pseudo random generator seed */
     printff("random generator... ");
     rand_init(RAND_SEED_DEFAULT);
 
+    printf("done.\n");
+
+    printff("initiazing board data: ");
     /* bitboards & hq */
     printff("bitboards... ");
     bitboard_init();
@@ -46,16 +51,25 @@ void init_all(void)
     printff("hq bitboards... ");
     hq_init();
 
+    printf("done.\n");
+
+    printff("initiazing move data: ");
     /* zobrist tables & default tt hashtable */
     printff("zobrist tables... ");
     zobrist_init();
 
-    printff("hash tables... ");
+    printff("transposition tables... ");
     tt_create(HASH_SIZE_DEFAULT);
 
+    printf("done.\n");
+
+    printff("initiazing eval data: ");
+    printf("parameters... ");
+    param_init();
+
     /* eval tables */
-    printf("pst data... ");
-    pst_init("cpw");
+    printf("pst tables... ");
+    pst_init(PST_DEFAULT);
 
     printf("done.\n");
 }

src/move-do.c

@@ -24,6 +24,7 @@
 #include "position.h"
 #include "move-do.h"
 #include "hash.h"
+#include "hist.h"
 
 /**
  * move_do() - do move.
@@ -59,14 +60,16 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
     hkey_t key = pos->key;
 
     *state = pos->state;                          /* save irreversible changes */
+    pos->prev = state;
 
     /* update key: switch turn, reset castling and ep */
     key ^= zobrist_turn;
     key ^= zobrist_castling[pos->castle];
     key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
 
-    ++pos->clock_50;
+    ++pos->ply50;
     ++pos->plycount;
+    ++pos->plyroot;
     pos->en_passant = SQUARE_NONE;
     pos->turn = them;
     pos->captured = captured;
@@ -76,16 +79,21 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
 
     if (is_promotion(move)) {
         bug_on(sq_rank(to) != sq_rel_rank(RANK_8, us));
-        new_piece = MAKE_PIECE(move_promoted(move), us);
+        piece_t promoted = move_promoted(move);
+        new_piece = MAKE_PIECE(promoted, us);
+        pos->phase += pt_phase(PAWN) - pt_phase(promoted);
     }
 
     if (captured != EMPTY) {
-        pos->clock_50 = 0;
-        bug_on(pos->board[to] == EMPTY || COLOR(pos->captured) != them);
+        pos->ply50 = 0;
+        pos->phase += pt_phase(PIECE(captured));
+
+        bug_on(COLOR(captured) != them);
         key ^= zobrist_pieces[captured][to];
         pos_clr_sq(pos, to);                      /* clear square */
     } else if (is_castle(move)) {                 /* handle rook move */
         square_t rookfrom, rookto;
+
         if (to > from) {
             rookfrom = sq_rel(H1, us);
             rookto = sq_rel(F1, us);
@@ -99,9 +107,10 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
         pos_clr_sq(pos, rookfrom);
         pos->castle = clr_castle(pos->castle, us);
     } else if (ptype == PAWN) {                   /* pawn non capture or e.p. */
-        pos->clock_50 = 0;
+        pos->ply50 = 0;
         if (from + up + up == to) {               /* if pawn double push, set e.p. */
             square_t ep = from + up;
+
             if (bb_pawn_attacks[us][ep] & pos->bb[them][PAWN]) {
                 pos->en_passant = ep;
                 key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
@@ -109,6 +118,8 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
         } else if (is_enpassant(move)) {          /* clear grabbed pawn */
             square_t grabbed = to - up;
             piece_t pc = pos->board[grabbed];
+
+            pos->phase += pt_phase(PAWN);
             key ^= zobrist_pieces[pc][grabbed];
             pos_clr_sq(pos, grabbed);
         }
@@ -151,7 +162,13 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
 
     pos->key = key;
 
+    pos->repcount = pos_repcount(pos);
+
+    /* consistency checks.
+     * Checks done only if compiled with '-DZOBRIST_VERIFY' or '-DPHASE_VERIFY'
+     */
     zobrist_verify(pos);
+    phase_verify(pos);
 
     return pos;
 }
@@ -209,6 +226,8 @@ pos_t *move_undo(pos_t *pos, const move_t move, const state_t *state)
 
     pos->state = *state;                          /* restore irreversible changes */
     pos->turn = us;
+    --pos->plycount;
+    --pos->plyroot;
     return pos;
 }
 
@@ -227,14 +246,16 @@ pos_t *move_do_alt(pos_t *pos, const move_t move, state_t *state)
     hkey_t key = pos->key;
 
     *state = pos->state;                          /* save irreversible changes */
+    pos->prev = state;
 
     /* update key: switch turn, reset castling and ep */
     key ^= zobrist_turn;
     key ^= zobrist_castling[pos->castle];
     key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
 
-    ++pos->clock_50;
+    ++pos->ply50;
     ++pos->plycount;
+    ++pos->plyroot;
     pos->en_passant = SQUARE_NONE;
     pos->turn = them;
     pos->captured = captured;
@@ -248,8 +269,7 @@ pos_t *move_do_alt(pos_t *pos, const move_t move, state_t *state)
     }
 
     if (captured != EMPTY) {
-        pos->clock_50 = 0;
-        //pos->captured = pos->board[to];           /* save capture info */
+        pos->ply50 = 0;
         bug_on(pos->board[to] == EMPTY || COLOR(pos->captured) != them);
         key ^= zobrist_pieces[captured][to];
         pos_clr_sq(pos, to);                      /* clear square */
@@ -268,7 +288,7 @@ pos_t *move_do_alt(pos_t *pos, const move_t move, state_t *state)
         pos_clr_sq(pos, rookfrom);
         pos->castle = clr_castle(pos->castle, us);
     } else if (ptype == PAWN) {                   /* pawn non capture or e.p. */
-        pos->clock_50 = 0;
+        pos->ply50 = 0;
         if (from + up + up == to) {               /* if pawn double push, set e.p. */
             square_t ep = from + up;
             if (bb_pawn_attacks[us][ep] & pos->bb[them][PAWN]) {
@@ -320,6 +340,7 @@ pos_t *move_do_alt(pos_t *pos, const move_t move, state_t *state)
 
     pos->key = key;
 
+    pos->repcount = pos_repcount(pos);
     zobrist_verify(pos);
 
     return pos;
@@ -361,5 +382,7 @@ pos_t *move_undo_alt(pos_t *pos, const move_t move, const state_t *state)
 
     pos->state = *state;                          /* restore irreversible changes */
     pos->turn = us;
+    --pos->plycount;
+    --pos->plyroot;
     return pos;
 }

src/move-gen.c

@@ -480,3 +480,18 @@ finish:
     return movelist;
     //return movelist->nmoves = moves - movelist->move;
 }
+
+/**
+ * pos_gen_legal() - generate position legal moves
+ * @pos: position
+ * @movelist: &movelist_t array to store moves
+ *
+ * Generate all @pos legal moves for player-to-move.
+ * @movelist is filled with the moves.
+ *
+ * @Return: movelist
+ */
+movelist_t *pos_gen_legal(pos_t *pos, movelist_t *movelist)
+{
+    return pos_legal(pos, pos_gen_pseudo(pos, movelist));
+}

src/move-gen.h

@@ -27,5 +27,6 @@ movelist_t *pos_legal_dup(const pos_t *pos, movelist_t *pseudo, movelist_t *lega
 movelist_t *pos_legal(const pos_t *pos, movelist_t *list);
 
 movelist_t *pos_gen_pseudo(pos_t *pos, movelist_t *movelist);
+movelist_t *pos_gen_legal(pos_t *pos, movelist_t *movelist);
 
 #endif  /* MOVEGEN_H */

src/perft.c

@@ -0,0 +1,194 @@
+/* perft.c - perft functions.
+ *
+ * Copyright (C) 2023-2024 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 <brlib.h>
+
+#include "perft.h"
+#include "move-gen.h"
+#include "move-do.h"
+
+/**
+ * do_perft() - perft engine
+ * @pos:    &position to search
+ * @depth:  Wanted depth.
+ *
+ * Run perft on a position.
+ *
+ * This version uses the algorithm:
+ *    gen legal moves
+ *    if last depth
+ *      return number of legal move
+ *    loop for legal move
+ *      do-move
+ *      if depth == 2
+ *
+ *      do_perft (depth -1)
+ *      undo-move
+ *
+ * @return: total moves found at @depth level.
+ */
+static u64 do_perft(pos_t *pos, int depth)
+{
+    u64 nodes = 0;
+    movelist_t movelist;
+    move_t *move, *last;
+    state_t state;
+
+    pos_set_checkers_pinners_blockers(pos);
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+
+    //if (depth == 1)
+    //    return movelist.nmoves;
+
+    last = movelist.move + movelist.nmoves;
+    switch (depth) {
+        case 1:
+            /* This case could be removed if 'case 2' is handled in perft()
+             */
+            return movelist.nmoves;
+            break;
+        case 2:
+            /* For depth 2, we directly calculate the possible legal moves
+             * after each possible moves.
+             */
+            for (move = movelist.move; move < last; ++move) {
+                move_do(pos, *move, &state);
+                movelist_t movelist2;
+                pos_set_checkers_pinners_blockers(pos);
+                nodes += pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
+                move_undo(pos, *move, &state);
+            }
+            break;
+        default:
+            /* Default: Search in TT for same key+depth. Use it if found, create
+             * it otherwise.
+             */
+            for (move = movelist.move; move < last; ++move) {
+                move_do(pos, *move, &state);
+                hentry_t *entry = tt_probe_perft(pos->key, depth);
+                if (entry != TT_MISS) {
+                    nodes += HASH_PERFT_VAL(entry->data);
+                } else {
+                    u64 subnodes = do_perft(pos, depth - 1);
+                    tt_store_perft(pos->key, depth, subnodes);
+                    nodes += subnodes;
+                }
+                move_undo(pos, *move, &state);
+            }
+            //} else {
+            //subnodes = do_perft(pos, depth - 1);
+    }
+        //move_undo(pos, *move, &state);
+        //nodes += subnodes;
+    //}
+
+    return nodes;
+}
+
+/**
+ * perft() - Perform perft on position
+ * @pos:    &position to search
+ * @depth:  Wanted depth.
+ * @ply:    current perft depth level (root = 1)
+ * @divide: output total for 1st level moves.
+ *
+ * Run perft on a position. This function displays the available moves at @depth
+ * level for each possible first move, and the total of moves.
+ *
+ * This version uses the algorithm:
+ *    if last depth
+ *      return 1;
+ *    gen legal moves
+ *    loop for legal move
+ *      do-move
+ *      perft (depth -1)
+ *      undo-move
+ *
+ * @return: total moves found at @depth level.
+ */
+u64 perft(pos_t *pos, int depth, bool divide)
+{
+    u64 subnodes = 0, nodes = 0;
+    movelist_t movelist;
+    move_t *move, *last;
+    state_t state;
+
+    pos_set_checkers_pinners_blockers(pos);
+
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+    last = movelist.move + movelist.nmoves;
+    for (move = movelist.move; move < last; ++move) {
+        if (depth == 1) {
+            subnodes = 1;
+        } else {
+            move_do(pos, *move, &state);
+            subnodes = do_perft(pos, depth - 1);
+            move_undo(pos, *move, &state);
+        }
+        if (divide) {
+            char movestr[8];
+            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
+        }
+        nodes += subnodes;
+    }
+    return nodes;
+}
+
+/**
+ * perft_alt() - Perform perft on position, experimental version.
+ * @pos:    &position to search
+ * @depth:  Wanted depth.
+ * @ply:    current perft depth level (root = 1)
+ * @divide: output total for 1st level moves.
+ *
+ * Run perft on a position. This function displays the available moves at @depth
+ * level for each possible first move, and the total of moves.
+ *
+ * @return: total moves found at @depth level.
+ */
+u64 perft_alt(pos_t *pos, int depth, int ply, bool divide)
+{
+    u64 subnodes = 0, nodes = 0;
+    movelist_t movelist;
+    move_t *move, *last;
+    state_t state;
+
+    pos_set_checkers_pinners_blockers(pos);
+
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+    last = movelist.move + movelist.nmoves;
+    for (move = movelist.move; move < last; ++move) {
+        if (depth == 1) {
+            subnodes = 1;
+        } else {
+            move_do_alt(pos, *move, &state);
+            if (depth == 2) {
+                movelist_t movelist2;
+                pos_set_checkers_pinners_blockers(pos);
+                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
+            } else {
+                subnodes = perft_alt(pos, depth - 1, ply + 1, divide);
+            }
+            move_undo_alt(pos, *move, &state);
+        }
+        nodes += subnodes;
+        if (ply == 1 && divide) {
+            char movestr[8];
+            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
+        }
+    }
+
+    return nodes;
+}

src/perft.h

@@ -0,0 +1,22 @@
+/* perft.h.h - perft.
+ *
+ * Copyright (C) 2021-2024 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 PERFT_H
+#define PERFT_H
+
+#include "position.h"
+
+u64 perft(pos_t *pos, int depth,/* int ply,*/ bool divide);
+u64 perft_alt(pos_t *pos, int depth, int ply, bool output);
+
+#endif  /* PERFT_H */

src/piece.h

@@ -47,6 +47,7 @@ enum __piece_e {
     PIECE_NB
 };
 typedef u8  piece_t;
+
 /* default values for midgame, endgame
  */
 #define E_VAL_MID    0
@@ -103,15 +104,14 @@ extern const char pieces_str[6+6+1];              /* to search from fen/user inp
 #define SET_BLACK(p)      (piece_t)((p) |= MASK_COLOR)
 #define SET_COLOR(p, c)   (piece_t)(!(c)? SET_WHITE(p): SET_BLACK(p))
 
-static __inline s16 piece_midval(piece_type_t pt)
+static __inline eval_t piece_midval(piece_type_t pt)
 {
     return piece_details[pt].mid_value;
 }
-static __inline s16 piece_endval(piece_type_t pt)
+static __inline eval_t piece_endval(piece_type_t pt)
 {
-    return piece_details[pt].mid_value;
+    return piece_details[pt].end_value;
 }
-#define piece_val(pt) piece_midval(pt)
 
 bool piece_ok(piece_t p);
 

src/position.c

@@ -100,31 +100,15 @@ pos_t *pos_clear(pos_t *pos)
 #   ifdef DEBUG_POS
     printf("size(pos_board=%lu elt=%lu\n", sizeof(pos->board), sizeof(int));
 #   endif
-    pos->node_count = 0;
-    pos->turn = WHITE;
+    memset(pos, 0, sizeof (pos_t));
 
-    /* move_do/undo position state */
-    pos->key = 0;
+    /* non-zero values */
     pos->en_passant = SQUARE_NONE;
-    pos->castle = 0;
-    pos->clock_50 = 0;
-    pos->plycount = 0;
     pos->move = MOVE_NONE;
-    pos->captured = NO_PIECE;
 
-    for (square_t sq = A1; sq <= H8; ++sq)
-        pos->board[sq] = EMPTY;
-
-    for (color_t color = WHITE; color <= BLACK; ++color) {
-        for (piece_type_t piece = 0; piece <= KING; ++piece)
-            pos->bb[color][piece] = 0;
-        //pos->controlled[color] = 0;
-        pos->king[color] = SQUARE_NONE;
-    }
-
-    pos->checkers = 0;
-    pos->pinners = 0;
-    pos->blockers = 0;
+    pos->king[WHITE] = SQUARE_NONE;
+    pos->king[BLACK] = SQUARE_NONE;
+    pos->prev = HIST_START;
 
     return pos;
 }
@@ -147,7 +131,7 @@ bool pos_cmp(const pos_t *pos1, const pos_t *pos2)
 
     /* move_do/undo position state */
     if (_cmpf(key) || _cmpf(en_passant) || _cmpf(castle) ||
-        _cmpf(clock_50) || _cmpf(plycount) || _cmpf(captured))
+        _cmpf(ply50) || _cmpf(plycount) || _cmpf(captured))
         goto end;
 
     if (_cmpf(checkers) || _cmpf(pinners) || _cmpf(blockers))
@@ -197,6 +181,36 @@ bitboard_t pos_checkers(const pos_t *pos, const color_t color)
     return sq_attackers(pos, occ, pos->king[color], OPPONENT(color));
 }
 
+/**
+ * pos_repcount() - return position repetition count.
+ * @pos: &position to search
+ *
+ * Attention: positions before (and including) root position repcount are
+ * already decreased by one. See do_moves() in uci.c.
+ *
+ * @return: The number of repetitions in history, zero otherwise.
+ */
+u8 pos_repcount(pos_t *pos)
+{
+    int c50 = pos->ply50;
+    state_t *st = &pos->state;
+    hkey_t key = pos->key;
+
+    st = hist_prev4(st);
+    //printf("is rep: START=%p ", HIST_START);
+    //printf("state=%p diff=%zd c50=%d k1=%#lx k2=%#lx\n",
+    //       st, st - HIST_START, c50, hash_short(pos->key), hash_short(st->key));
+
+    /* attention, what about root position ? Isn't it dangerous to compare with
+     * its key ? like: st->prev != HIST_START
+     */
+    for (; c50 >= 0 && st != HIST_START; st = hist_prev2(st), c50 -= 2) {
+        if (key == st->key)
+            return st->repcount + 1;
+    }
+    return false;
+}
+
 /**
  * pos_set_checkers_pinners_blockers() - calculate checkers, pinners and blockers.
  * @pos:   &position

src/position.h

@@ -27,6 +27,7 @@
 #include "piece.h"
 #include "move.h"
 #include "board.h"
+#include "eval-defs.h"
 
 typedef struct __pos_s {
     u64 node_count;                               /* evaluated nodes */
@@ -50,14 +51,14 @@ typedef struct __pos_s {
 
                         /* 16 bits */
                         move_t move;
-                        u16 plycount;             /* plies so far, start from 1 */
-                        s16 phase;
 
                         /* 8 bits */
                         square_t en_passant;
                         castle_rights_t castle;
                         piece_t captured;         /* only used in move_undo */
-                        u8 clock_50;
+                        phase_t phase;
+                        u8 ply50;
+                        u8 repcount;              /* repetition count */
         );
     eval_t eval;
     bitboard_t checkers;                          /* opponent checkers */
@@ -66,6 +67,8 @@ typedef struct __pos_s {
     piece_t board[BOARDSIZE];
     bitboard_t bb[2][PT_NB];                      /* bb[0][PAWN], bb[1][ALL_PIECES] */
     square_t king[2];                             /* dup with bb, faster retrieval */
+    u16 plycount;                                 /* plies in game, start from 1 */
+    u8 plyroot;                                   /* plies since search root. root=0 */
 } pos_t;
 
 typedef struct state_s state_t;
@@ -183,6 +186,7 @@ void pos_del(pos_t *pos);
 pos_t *pos_clear(pos_t *pos);
 bool pos_cmp(const pos_t *pos1, const pos_t *pos2);
 
+u8 pos_repcount(pos_t *pos);
 void pos_set_checkers_pinners_blockers(pos_t *pos);
 void pos_set_pinners_blockers(pos_t *pos);
 bitboard_t pos_checkers(const pos_t *pos, const color_t color);

src/pv.h

@@ -0,0 +1,53 @@
+/* pv.c - Principal variation.
+ *
+ * Copyright (C) 2024 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 <ctype.h>
+
+#include <brlib.h>
+
+#include "move.h"
+
+/*
+ * For PV, we use a triangular structure. The following table is adapted from
+ * https://www.chessprogramming.org/Triangular_PV-Table.
+ *
+ * ply     Search   maxLengthPV
+ *         Depth
+ *                  +--------------------------------------------+
+ * 0=root  N        |N                                           |
+ *                  +------------------------------------------+-+
+ * 1       N-1      |N-1                                       |
+ *                  +----------------------------------------+-+
+ * 2       N-2      |N-2                                     |
+ *                  +----------------------------------------+-+
+ * ...                                     /
+ *                  +-----+-+
+ * N-3     3        |3    |
+ *                  +---+-+
+ * N-2     2        |2  |
+ *                  +-+-+
+ * N-1     1        |1|
+ *                  +-+
+ *
+ * The offsets will be:
+ * Depth (=size):  1  2  3  4  5  6  7 ...
+ * Offset:         0  1  3  6 10 15 21 ...
+ *
+ * Off(n)     = n * (n - 1) / 2      (direct calc)
+ * Off(n + 1) = Off(n) + n           (calc from previous)
+ */
+
+typedef struct {
+    move[];
+} foo;

src/search.c

@@ -1,4 +1,4 @@
-/* search.c - perft + search.
+/* search.c - search for perfect move.
  *
  * Copyright (C) 2023-2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -15,121 +15,29 @@
 
 #include <brlib.h>
 
+#include "chessdefs.h"
+
 #include "position.h"
 #include "move-gen.h"
 #include "move-do.h"
 #include "search.h"
 #include "attack.h"
+#include "hist.h"
+
+search_uci_t search_uci;
 
 /**
- * perft() - Perform perft on position
- * @pos:    &position to search
- * @depth:  Wanted depth.
- * @ply:    current perft depth level (root = 1)
- * @divide: output total for 1st level moves.
+ * is_draw() - check if position is draw by 50 or repetition rule.
+ * @pos: &position to search
  *
- * Run perft on a position. This function displays the available moves at @depth
- * level for each possible first move, and the total of moves.
+ * Note that states before (and including) root position state have
+ * their repcount decreased by one.
  *
- * This version uses the algorithm:
- *    if last depth
- *      return 1;
- *    gen legal moves
- *    loop for legal move
- *      do-move
- *      perft (depth -1)
- *      undo-move
- *
- * @return: total moves found at @depth level.
+ * @return: The @pos negamax evaluation.
  */
-u64 perft(pos_t *pos, int depth, int ply, bool divide)
+bool is_draw(pos_t *pos)
 {
-    u64 subnodes = 0, nodes = 0;
-    movelist_t movelist;
-    move_t *move, *last;
-    state_t state;
-
-    pos_set_checkers_pinners_blockers(pos);
-
-    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
-    last = movelist.move + movelist.nmoves;
-    for (move = movelist.move; move < last; ++move) {
-        if (depth == 1) {
-            subnodes = 1;
-        } else {
-            move_do(pos, *move, &state);
-            if (depth == 2) {
-                movelist_t movelist2;
-                pos_set_checkers_pinners_blockers(pos);
-                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
-            } else if (ply >= 3) {
-                hentry_t *entry = tt_probe_perft(pos->key, depth);
-                if (entry != TT_MISS) {
-                    subnodes = HASH_PERFT_VAL(entry->data);
-                } else {
-                    subnodes = perft(pos, depth - 1, ply + 1, divide);
-                    tt_store_perft(pos->key, depth, subnodes);
-                }
-            } else {
-                subnodes = perft(pos, depth - 1, ply + 1, divide);
-            }
-            move_undo(pos, *move, &state);
-        }
-        nodes += subnodes;
-        if (ply == 1 && divide) {
-            char movestr[8];
-            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
-        }
-    }
-
-    return nodes;
-}
-
-/**
- * perft_alt() - Perform perft on position, experimental version.
- * @pos:    &position to search
- * @depth:  Wanted depth.
- * @ply:    current perft depth level (root = 1)
- * @divide: output total for 1st level moves.
- *
- * Run perft on a position. This function displays the available moves at @depth
- * level for each possible first move, and the total of moves.
- *
- * @return: total moves found at @depth level.
- */
-u64 perft_alt(pos_t *pos, int depth, int ply, bool divide)
-{
-    u64 subnodes = 0, nodes = 0;
-    movelist_t movelist;
-    move_t *move, *last;
-    state_t state;
-
-    pos_set_checkers_pinners_blockers(pos);
-
-    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
-    last = movelist.move + movelist.nmoves;
-    for (move = movelist.move; move < last; ++move) {
-        if (depth == 1) {
-            subnodes = 1;
-        } else {
-            move_do_alt(pos, *move, &state);
-            if (depth == 2) {
-                movelist_t movelist2;
-                pos_set_checkers_pinners_blockers(pos);
-                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
-            } else {
-                subnodes = perft_alt(pos, depth - 1, ply + 1, divide);
-            }
-            move_undo_alt(pos, *move, &state);
-        }
-        nodes += subnodes;
-        if (ply == 1 && divide) {
-            char movestr[8];
-            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
-        }
-    }
-
-    return nodes;
+    return (pos->ply50 > 100 || pos->repcount);
 }
 
 /**
@@ -143,35 +51,57 @@ u64 perft_alt(pos_t *pos, int depth, int ply, bool divide)
  *
  * @return: The @pos negamax evaluation.
  */
-/*
- * eval_t negamax(pos_t *pos, int depth, int color)
- * {
- *     move_t *move;
- *     pos_t *newpos;
- *     eval_t best = EVAL_MIN, score;
- *
- *     pos->node_count++;
- *     if (depth == 0) {
- *         moves_gen_all_nomoves(pos);
- *         score = eval(pos) * color;
- *         return score;
- *     }
- *     moves_gen_all(pos);
- *     list_for_each_entry(move, &pos->moves[pos->turn], list) {
- *         newpos = move_do(pos, move);
- *         score = -negamax(newpos, depth - 1, -color);
- *         pos->node_count += newpos->node_count;
- *         move->negamax = score;
- *         if (score > best) {
- *             best = score;
- *             pos->bestmove = move;
- *         }
- *         move_undo(newpos, move);
- *     }
- *     return best;
- * }
- */
+eval_t negamax(pos_t *pos, int depth, int color)
+{
+    move_t *move, *last;
+    state_t state;
+    eval_t best = EVAL_MIN, score;
+    movelist_t movelist;
 
+    pos->node_count++;
+
+    if (pos_repcount(pos))                        /* repetition */
+        return EVAL_DRAW * color;
+
+    pos_set_checkers_pinners_blockers(pos);
+    pos_gen_legal(pos, &movelist);
+
+    if (!movelist.nmoves)                         /* no move: mate ot draw */
+        return (pos->checkers? EVAL_MATE: EVAL_DRAW) * color;
+
+    if (depth == 0) {
+        score = eval(pos) * color;
+        return score;
+    }
+
+    last = movelist.move + movelist.nmoves;
+    for (move = movelist.move; move < last; ++move) {
+        move_do(pos, *move, &state);
+        score = -negamax(pos, depth - 1, -color);
+        if (score > best) {
+            best = score;
+            pos->eval = best;
+        }
+        move_undo(pos, *move, &state);
+    }
+    return best;
+}
+
+/**
+ * search() - do (iterative) search.
+ * @pos: &position to search
+ * @depth: wanted depth.
+ * @alpha: alpha.
+ * @beta: beta.
+ * @color: 1 for white, -1 for black.
+ *
+ *
+ * @return: The @pos PVS evaluation.
+ */
+void search(__unused pos_t *pos)
+{
+
+}
 
 /**
  * pvs() - Principal Variation Search.

src/search.h

@@ -16,10 +16,21 @@
 
 #include "position.h"
 
-//eval_t negamax(pos_t *pos, int depth, int color);
+/**
+ * search_values_t - search values given by "go" command
+ * @depth: max depth "go depth X", MAX_DEPTH for no limit
+ *
+ *
+ */
+typedef struct {
+    u16 depth;                                    /* go depth X */
+} search_uci_t;
+
+extern search_uci_t search_uci;
+
+bool is_draw(pos_t *pos);
+eval_t negamax(pos_t *pos, int depth, int color);
+void search(pos_t *pos);
 //eval_t pvs(pos_t *pos, int depth, int alpha, int beta, int color);
 
-u64 perft(pos_t *pos, int depth, int ply, bool output);
-u64 perft_alt(pos_t *pos, int depth, int ply, bool output);
-
 #endif  /* SEARCH_H */

src/thread.c

@@ -0,0 +1,70 @@
+/* thread.c - thread management.
+ *
+ * Copyright (C) 2024 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 <brlib.h>
+#include <pthread.h>
+#include <poll.h>
+#include <sys/socket.h>
+
+#include "thread.h"
+
+/* Still have to decide: thread or process ?
+ *
+ */
+thread_pool_t threadpool;
+
+
+/**
+ * thrd_create - initialize thrd.
+ */
+int thrd_create(__unused int num)
+{
+    int fd[2];
+    /* shall we make a communication channel via a pipe or socket ? */
+    int __unused ret = socketpair(AF_LOCAL, SOCK_SEQPACKET, PF_LOCAL, fd);
+    return 1;
+}
+
+/**
+ * thread_init - initialize thread pool.
+ */
+int thread_init(int nb)
+{
+    nb = clamp(nb, MIN_THRDS, MAX_THRDS);
+
+    /* stop unwanted threads, always keep 1 */
+    for (int i = nb + 1; i < threadpool.nb; ++i) {
+        printf("stopping thread %d - status = \n", i);
+        threadpool.thread[i].cmd = THRD_DO_QUIT;
+    }
+    for (int i = threadpool.nb; i < nb; ++i) {
+        printf("creating thread %d - status = \n", i);
+        thrd_create(i);
+
+    }
+
+    return nb;
+}
+
+/*
+  communication:
+  main thread -> thread
+           commands via memory
+  thread -> main thread
+           status via memory
+           output via pipe/socket
+  thread output will be output/filtered by main thread
+
+ */

src/thread.h

@@ -0,0 +1,55 @@
+/* thread.h - thread management.
+ *
+ * Copyright (C) 2021-2024 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 THREAD_H
+#define THREAD_H
+
+#include <pthread.h>
+
+#include <brlib.h>
+
+#include "position.h"
+
+#define MIN_THRDS 1
+#define MAX_THRDS 16
+
+typedef enum {
+    THRD_DEAD,
+    THRD_IDLE,
+    THRD_WORKING,
+} thread_status_t;
+
+typedef enum {
+    /* main thread to subs */
+    THRD_DO_SEARCH,
+    THRD_DO_STOP,
+    THRD_DO_QUIT,
+} thread_cmd_t;
+
+typedef struct {
+    int id;
+    thread_status_t status;
+    thread_cmd_t cmd;
+    int fd[2];
+    pos_t pos;
+} thread_t;
+
+typedef struct {
+    int nb;
+    thread_t thread[MAX_THRDS + 1];
+} thread_pool_t;
+
+int thrd_create(__unused int num);
+int thread_init(int nb);
+
+#endif  /* THREAD_H */

src/uci.c

@@ -1,6 +1,6 @@
 /* uci.c - uci protocol
  *
- * Copyright (C) 2024 Bruno Raoult ("br")
+ * Copyright (C) 2021-2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
  * Some rights reserved. See COPYING.
  *
@@ -11,43 +11,47 @@
  *
  */
 
-
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
-#include <ctype.h>
 #include <unistd.h>
+#include <ctype.h>
 
 #include <brlib.h>
+#include <bug.h>
 
 #include "chessdefs.h"
+#include "util.h"
 #include "position.h"
-#include "uci.h"
 #include "hist.h"
 #include "fen.h"
 #include "move-gen.h"
 #include "move-do.h"
 #include "search.h"
+#include "perft.h"
+#include "eval-defs.h"
+#include "uci.h"
 
 struct command {
-    char *name;                                   /* User printable name */
+    char *name;                                   /* command name */
     int (*func)(pos_t *, char *);                 /* function doing the job */
     char *doc;                                    /* function doc */
 };
 
 int execute_line (pos_t *, struct command *, char *);
-
 struct command *find_command (char *);
-int string_trim (char *str);
 
-/* The names of functions that actually do the manipulation. */
+/* The names of functions that actually do the stuff.
+ */
 
 /* standard UCI commands */
 int do_ucinewgame(pos_t *, char *);
 int do_uci(pos_t *, char *);
 int do_isready(pos_t *, char *);
+int do_quit(pos_t *, char *);
 
+int do_setoption(pos_t *, char *);
 int do_position(pos_t *, char *);
+int do_go(pos_t *, char *);
 
 /* commands *NOT* in UCI standard */
 int do_moves(pos_t *, char *);
@@ -56,54 +60,27 @@ int do_perft(pos_t *, char *);
 
 int do_hist(pos_t *, char *);
 int do_help(pos_t *, char *);
-int do_quit(pos_t *, char *);
 
 struct command commands[] = {
-    { "help",       do_help, "(not UCI) This help" },
-    { "?",          do_help, "(not UCI) This help" },
     { "quit",       do_quit, "Quit" },
-
     { "uci",        do_uci, "" },
     { "ucinewgame", do_ucinewgame, "" },
     { "isready",    do_isready, "" },
-
+    { "setoption",  do_setoption, ""},
     { "position",   do_position, "position startpos|fen [moves ...]" },
+    { "go",         do_go, "go" },
+
 
     { "perft",      do_perft, "(not UCI) perft [divide] [alt] depth" },
     { "moves",      do_moves, "(not UCI) moves ..." },
     { "diagram",    do_diagram, "(not UCI) print current position diagram" },
     { "hist",       do_hist, "(not UCI) print history states" },
+    { "help",       do_help, "(not UCI) This help" },
+    { "?",          do_help, "(not UCI) This help" },
 
     { NULL, (int(*)()) NULL, NULL }
 };
 
-static int done = 0;
-
-int uci(pos_t *pos)
-{
-    char *str = NULL, *saveptr, *token, *args;
-    int len;
-    size_t lenstr = 0;
-    struct command *command;
-
-    while (!done && getline(&str, &lenstr, stdin) >= 0) {
-        if (!(len = string_trim(str)))
-            continue;
-        token = strtok_r(str, " ", &saveptr);
-        if (! (command= find_command(token))) {
-            fprintf(stderr, "Unknown [%s] command. Try 'help'.\n", token);
-            continue;
-        }
-        args = strtok_r(NULL, "", &saveptr);
-        execute_line(pos, command, args);
-    }
-
-    if (str)
-        free(str);
-
-    return 0;
-}
-
 /* Execute a command line. */
 int execute_line(pos_t *pos, struct command *command, char *args)
 {
@@ -115,7 +92,7 @@ int execute_line(pos_t *pos, struct command *command, char *args)
  * @name: &command string
  *
  * Look up NAME as the name of a command, and return a pointer to that
- *   command.  Return a NULL pointer if NAME isn't a command name.
+ * command.  Return a NULL pointer if NAME isn't a command name.
  */
 struct command *find_command(char *name)
 {
@@ -252,8 +229,37 @@ int do_uci(__unused pos_t *pos, __unused char *arg)
 {
     printf("id name brchess " VERSION "\n");
     printf("id author Bruno Raoult\n");
-    printf("option option name Hash type spin default %d min %d max %d\n",
+    printf("option name Hash type spin default %d min %d max %d\n",
            hash_tt.mb, HASH_SIZE_MIN, HASH_SIZE_MAX);
+
+    if (PST_NB > 1) {
+        printf("option name pst type combo default %s",
+               pst_name(pst_current));
+        for (int i = 0; i < PST_NB; ++i)
+            printf(" var %s", pst_name(i));
+    }
+    printf("\n");
+    for (int var = 0; var < EV_PARAMS_NB; ++var) {
+        if (param_setable(var)) {
+            int ptyp = param_type(var);
+            int pmin = param_min(var);
+            int pmax = param_max(var);
+            int pval = parameters[var];
+
+            printf("option name %s ", param_name(var));
+            switch(ptyp) {
+                case PAR_BTN:
+                    printf("type button\n");
+                    break;
+                case PAR_CHK:
+                    printf("type check default %s\n", pval? "true": "false");
+                    break;
+                case PAR_SPN:
+                    printf("type spin default %d min %d max %d\n", pval, pmin, pmax);
+                    break;
+            };
+        }
+    }
     printf("uciok\n");
     return 1;
 }
@@ -264,17 +270,80 @@ int do_isready(__unused pos_t *pos, __unused char *arg)
     return 1;
 }
 
+int do_setoption(__unused pos_t *pos, __unused char *arg)
+{
+    char *name, *value = NULL;
+
+    if (str_token(arg, "name") != arg)
+        return 1;
+    if (!(name = str_skip_word(arg)))
+        return 1;
+    /* at this point, we got a valid parameter name */
+    value = str_token(name, "value");             /* put '\0' at name end */
+    if (value) {
+        value = str_skip_word(value);
+        if (!value)
+            return 1;
+    }
+    if (str_eq_case(name, "hash") && value) {
+        tt_create(atoi(value));
+    } else if (str_eq_case(name, "pst")) {
+        pst_set(value);
+    } else {
+        int var = param_find_name(name);
+        if (var < 0) {
+            printf("wrong parameter '%s'\n", name);
+            return 1;
+        }
+        char *pname = param_name(var);
+        printf("found param <%s> = %d\n", pname, var);
+        if (param_setable(var)) {
+            int ptyp = param_min(var);
+            int pmin = param_min(var);
+            int pmax = param_max(var);
+            int pval;
+
+            switch(ptyp) {
+                case PAR_BTN:
+                    bug_on (value);
+                    printf("do button '%s'\n", pname);
+                    break;
+                case PAR_CHK:
+                    bug_on (!value);
+                    if (str_eq_case(value, "true"))
+                        pval = 1;
+                    else if (str_eq_case(value, "false"))
+                        pval = 0;
+                    else {
+                        printf("wrong value '%s' to '%s' boolean parameter\n",
+                               value, pname);
+                        return 1;
+                    }
+                    printf("set '%s' to %s\n", pname, pval? "true": "false");
+                    param_set(var, pval);
+                    break;
+                case PAR_SPN:
+                    bug_on (!value);
+                    pval = clamp(atoi(value), pmin, pmax);
+                    printf("set '%s' to %d\n", param_name(var), pval);
+                    param_set(var, pval);
+                    break;
+            }
+        }
+    }
+
+    return 0;
+}
+
+
 int do_position(pos_t *pos, char *arg)
 {
-    char *saveptr, *token, *fen, *moves;
+    char *saveptr = NULL, *token, *fen, *moves;
 
     hist_init();
 
     /* separate "moves" section */
-    if ((moves = strstr(arg, "moves"))) {
-        *(moves - 1) = 0;
-    }
-    saveptr = NULL;
+    moves = str_token(arg, "moves");
     token = strtok_r(arg, " ", &saveptr);
     if (!strcmp(token, "startpos")) {
         startpos(pos);
@@ -304,7 +373,51 @@ int do_position(pos_t *pos, char *arg)
     }
     /* link last position t history */
     //hist_pop();
-    hist_link(pos);
+    //hist_link(pos);
+    return 1;
+}
+
+
+int do_go(pos_t *pos, char *arg)
+{
+    char *ptr = NULL, *tok, *val;
+
+    //token = strtok_r(arg, " ", &saveptr);
+    for (tok = strtok_r(arg, " ", &ptr); tok; tok = strtok_r(arg, " ", &ptr)) {
+        /* TODO: Find a "clever" way to get the different values without
+         * multiple "strcmp"
+         */
+
+        if (!strcmp(tok, "searchmoves")) {        /* moves list */
+            ;
+        } else if (!strcmp(tok, "wtime")) {       /* integer */
+            ;
+        } else if (!strcmp(tok, "btime")) {       /* integer */
+            ;
+        } else if (!strcmp(tok, "winc")) {        /* integer */
+            ;
+        } else if (!strcmp(tok, "binc")) {        /* integer */
+            ;
+        } else if (!strcmp(tok, "movestogo")) {   /* integer */
+            ;
+        } else if (!strcmp(tok, "depth")) {       /* integer */
+            if ((val = strtok_r(arg, " ", &ptr)))
+                search_uci.depth = atoi(val);
+            ;
+        } else if (!strcmp(tok, "nodes")) {       /* integer */
+            ;
+        } else if (!strcmp(tok, "mate")) {        /* integer */
+            ;
+        } else if (!strcmp(tok, "movetime")) {    /* integer */
+            ;
+        } else if (!strcmp(tok, "ponder")) {      /* no param */
+            ;
+        } else if (!strcmp(tok, "infinite")) {    /* no param */
+            ;
+        }
+
+    }
+    search(pos);
     return 1;
 }
 
@@ -312,9 +425,8 @@ int do_moves(__unused pos_t *pos, char *arg)
 {
     char *saveptr = NULL, *token, check[8];
     move_t move;
-    state_t state;
     movelist_t movelist;
-    saveptr = NULL;
+
     token = strtok_r(arg, " ", &saveptr);
     while (token) {
         move = move_from_str(token);
@@ -329,13 +441,26 @@ int do_moves(__unused pos_t *pos, char *arg)
             return 1;
         }
         //printf("move: %s\n", move_to_str(check, move, 0));
-        hist_push(&pos->state);                   /* push previous state */
-        move_do(pos, move, &state);
-        pos_print(pos);
+        //hist_push(&pos->state);                   /* push previous state */
+        move_do(pos, move, hist_next());
+        printf("repet=%d\n", pos->repcount);
+        //if (is_repetition(pos))
+        //    printf("rep detected\n");
+        //else if(is_draw(pos))
+        //    printf("draw detected\n");
         hist_static_print();
         token = strtok_r(NULL, " ", &saveptr);
     }
-    //hist_static_print();
+    /* reset position root, and decrease history moves repcounts.
+     * TODO: Maybe use "ucinewgame" to decide when to perform this decrease ?
+     */
+    pos->plyroot = 0;
+    for (state_t *st = &pos->state; st != HIST_START; st = hist_prev(st)) {
+        //printf("adjust rep=%d->\n");
+        st->repcount = max(0, st->repcount - 1);
+    }
+    pos_print(pos);
+    hist_print(pos);
     return 1;
 }
 
@@ -363,17 +488,16 @@ int do_perft(__unused pos_t *pos, __unused char *arg)
     printf("perft: divide=%d alt=%d depth=%d\n", divide, alt, depth);
     if (depth > 0) {
         if (!alt)
-            perft(pos, depth, 1, divide);
+            perft(pos, depth, divide);
         else
             perft_alt(pos, depth, 1, divide);
     }
     return 1;
 }
 
-
 int do_hist(__unused pos_t *pos, __unused char *arg)
 {
-    hist_static_print();
+    hist_print(pos);
     return 0;
 }
 
@@ -387,11 +511,6 @@ int do_help(__unused pos_t *pos, __unused char *arg)
     return 0;
 }
 
-int do_quit(__unused pos_t *pos, __unused char *arg)
-{
-    return done = 1;
-}
-
 /*
  * int do_depth(__unused pos_t *pos, char *arg)
  * {
@@ -448,45 +567,35 @@ int do_quit(__unused pos_t *pos, __unused char *arg)
  * }
  */
 
-/**
- * string_trim - cleanup (trim) blank characters in string.
- * @str: &string to clean
- *
- * str is cleaned and packed with the following rules:
- * - Leading and trailing blank characters are removed.
- * - consecutive blank characters are replaced by one space.
- * - non printable characters are removed.
- *
- * "blank" means characters as understood by isspace(3): space, form-feed ('\f'),
- * newline ('\n'), carriage return ('\r'), horizontal tab  ('\t'), and vertical
- * tab ('\v').
- *
- * @return: new @str len.
- */
-int string_trim(char *str)
-{
-    char *to = str, *from = str;
-    int state = 1;
 
-    while (*from) {
-        switch (state) {
-            case 1:                               /* blanks */
-                while (*from && isspace(*from))
-                    from++;
-                state = 0;
-                break;
-            case 0:                               /* token */
-                while (*from && !isspace(*from)) {
-                    if (isprint(*from))
-                        *to++ = *from;
-                    from++;
-                }
-                *to++ = ' ';
-                state = 1;
-        }
-    }
-    if (to > str)
-        to--;
-    *to = 0;
-    return to - str;
+static int done = 0;
+
+int do_quit(__unused pos_t *pos, __unused char *arg)
+{
+    return done = 1;
+}
+
+int uci(pos_t *pos)
+{
+    char *str = NULL, *saveptr, *token, *args;
+    size_t lenstr = 0;
+    struct command *command;
+
+    while (!done && getline(&str, &lenstr, stdin) >= 0) {
+        str = str_trim(str);
+        if (! *str)
+            continue;
+        token = strtok_r(str, " ", &saveptr);
+        if (! (command = find_command(token))) {
+            fprintf(stderr, "Unknown [%s] command. Try 'help'.\n", token);
+            continue;
+        }
+        args = strtok_r(NULL, "", &saveptr);
+        execute_line(pos, command, args);
+    }
+
+    if (str)
+        free(str);
+
+    return 0;
 }

src/uci.h

@@ -1,4 +1,4 @@
-/* util.h - various util functions.
+/* uci.h - main loop.
  *
  * Copyright (C) 2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -11,8 +11,11 @@
  *
  */
 
-#ifndef _UTIL_H
-#define _UTIL_H
+#ifndef UCI_H
+#define UCI_H
 
+#include "position.h"
 
-#endif  /* UTIL_H */
+int uci(pos_t *pos);
+
+#endif  /* UCI_H */

src/util.c

@@ -1,4 +1,4 @@
-/* misc.c - generic/catchall functions.
+/* util.c - generic/catchall functions.
  *
  * Copyright (C) 2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -11,12 +11,15 @@
  *
  */
 
-#include <time.h>
-#include <stdlib.h>
+//#include <time.h>
+//#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
 
 #include <bug.h>
 
 #include "chessdefs.h"
+#include "util.h"
 
 /*
  * 1 sec      = 1000 millisec
@@ -34,10 +37,6 @@
 
 #define MICRO_IN_MILLI 1000ll
 
-//#define NANO_IN_MILLI  1000000ll                         /* nanosecond in millisecond */
-//#define NANO_IN_SEC    (NANOS_IN_MS * MS_IN_SEC)
-
-
 /**
  * clock_start - start or restart a clock.
  * @clock: &mclock_t clock
@@ -150,3 +149,126 @@ u64 rand64(void)
     rand_seed ^= rand_seed >> 27;
     return rand_seed * 0x2545f4914f6cdd1dull;
 }
+
+/**
+ * str_eq_case - test if two strings are equal ignoring case
+ * @str1: string1
+ * @str2: string2
+ *
+ * Compare @str1 and @str2 byte-by-byte, ignoring case.
+ *
+ * @return: true is equal, false otherwise.
+ */
+bool str_eq_case(char *str1, char *str2)
+{
+    uchar *s1 = (uchar *) str1;
+    uchar *s2 = (uchar *) str2;
+
+    for (; *s1 && *s2; ++s1, ++s2) {
+        if (tolower(*s1) != tolower(*s2))
+            break;
+    }
+    //printf("d=%lu *s1=%d *s2=%d\n", s1 - (uchar *) str1, *s1, *s2);
+    return *s2 == *s1;
+}
+
+/**
+ * str_trim - cleanup (trim) blank characters in string.
+ * @str: &string to clean
+ *
+ * str is cleaned and packed with the following rules:
+ * - Leading and trailing blank characters are removed.
+ * - consecutive blank characters are replaced by one space.
+ * - non printable characters are removed.
+ *
+ * "blank" means characters as understood by isspace(3): space, form-feed ('\f'),
+ * newline ('\n'), carriage return ('\r'), horizontal tab  ('\t'), and vertical
+ * tab ('\v').
+ *
+ * @return: new @str len.
+ */
+char *str_trim(char *str)
+{
+    char *to = str, *from = str;
+    int state = 1;
+
+    bug_on(!str);
+    while (*from) {
+        switch (state) {
+            case 1:                               /* blanks */
+                while (*from && isspace(*from))
+                    from++;
+                state = 0;
+                break;
+            case 0:                               /* token */
+                while (*from && !isspace(*from)) {
+                    if (isprint(*from))
+                        *to++ = *from;
+                    from++;
+                }
+                *to++ = ' ';
+                state = 1;
+        }
+    }
+    if (to > str)
+        to--;
+    *to = 0;
+    return str;
+}
+
+/**
+ * str_token - split a string from next token.
+ * @str:   string to search
+ * @token: token to look for
+ *
+ * Look for token @token in string @str, and if found, split @str just before it.
+ * A token is a string delimited by one space character. However, it may contain
+ * space characters itself.
+ * @str should normally be normalized with @str_trim(), so that all consecutive
+ * blank characters are replaced by one, and leading/trailing ones removed.
+ *
+ * @return: @token address if found, NULL otherwise.
+ */
+char *str_token(char *str, const char *token)
+{
+    int len = strlen(token);
+    char *found = str;
+
+    bug_on(!str || !token);
+    if (!*token)                                  /* nothing to search */
+        return str;
+
+    while (found && *found) {
+        //printf("trying pos=%ld\n", found - str);
+        found = strstr(found, token);
+        if (found) {
+            if (!found[len] || isspace(found[len]))
+                break;
+            found = strchr(found, ' ') + 1;
+            //printf("new pos=%ld\n", found - str);
+        }
+    }
+    if (found > str)                              /* split string */
+        *(found - 1) = 0;
+    return found;
+}
+
+/**
+ * str_skip_word - find next word in a string.
+ * @str:   input string
+ *
+ * skip current word and following blank char.
+ * @str must be normalized with @str_trim(), so that all consecutive blank
+ * characters are already replaced by one, and leading/trailing ones removed.
+ * Note that 'word' means any sequence of non-space character.
+ *
+ * @str is not modified.
+ *
+ * @return: next word if found, NULL otherwise.
+ */
+char *str_skip_word(char *str)
+{
+    bug_on(!str);
+    str = strchr(str, ' ');
+    return str? str + 1: NULL;
+}

src/util.h

@@ -0,0 +1,61 @@
+/* util.h - various util functions.
+ *
+ * Copyright (C) 2024 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 _UTIL_H
+#define _UTIL_H
+
+#include <brlib.h>
+
+#include <time.h>
+
+typedef struct mclock {
+    clockid_t clocktype;
+    ulong elapsed_l;
+    double elapsed_f;
+    struct timespec start;
+} mclock_t;
+
+#define CLOCK_WALL    CLOCK_REALTIME
+#define CLOCK_SYSTEM  CLOCK_MONOTONIC_RAW
+#define CLOCK_PROCESS CLOCK_PROCESS_CPUTIME_ID
+#define CLOCK_THREAD  CLOCK_THREAD_CPUTIME_ID
+
+/**
+ * CLOCK_DEFINE - define a clock type.
+ * @name: clock name
+ * @type: clock type
+ *
+ * This macro is equivalent to:
+ *   mclock_t name;
+ *   clock_init(&name, type);
+ */
+#define CLOCK_DEFINE(name, type) struct mclock name = { .clocktype = type }
+
+void clock_init(mclock_t *clock, clockid_t type);
+void clock_start(mclock_t *clock);
+s64 clock_elapsed_μs(mclock_t *clock);
+s64 clock_elapsed_ms(mclock_t *clock);
+double clock_elapsed_sec(mclock_t *clock);
+
+#define RAND_SEED_DEFAULT U64(0xb0d1ccea)
+
+void rand_init(u64 seed);
+u64 rand64(void);
+
+
+bool str_eq_case(char *str1, char *str2);
+char *str_trim(char *str);
+char *str_token(char *str, const char *token);
+char *str_skip_word(char *str);
+
+#endif  /* UTIL_H */

test/perft-test.c

@@ -19,12 +19,13 @@
 #include <limits.h>
 
 #include "chessdefs.h"
+#include "util.h"
 #include "fen.h"
 #include "position.h"
 #include "move.h"
 #include "move-do.h"
 #include "move-gen.h"
-#include "search.h"
+#include "perft.h"
 
 #include "common-test.h"
 
@@ -363,7 +364,7 @@ int main(int ac, char**av)
 
         if (run & 1) {
             clock_start(&clock);
-            my_count = perft(pos, depth, 1, divide);
+            my_count = perft(pos, depth, divide);
             ms = clock_elapsed_ms(&clock);
             if (!ms) {
                 res[0].skipped++;