pseudo-moves for pieces (not pawns nor special moves)

.gitignore

@@ -5,3 +5,4 @@ GTAGS
 fen
 pool
 piece
+move

Makefile

@@ -6,7 +6,7 @@ SRCDIR=./src
 SRC=$(wildcard $(SRCDIR)/*.c)
 INC=$(wildcard $(SRCDIR)/*.h)
 
-BIN=fen pool piece
+BIN=fen pool piece move
 
 CFLAGS += -std=gnu99
 CFLAGS += -g
@@ -37,3 +37,8 @@ piece: CFLAGS+=-DPIECEBIN
 piece: $(SRC)
 	echo SRC=$(SRC)
 	$(CC) $(CFLAGS) $? -o $@
+
+move: CFLAGS+=-DMOVEBIN
+move: $(SRC)
+	echo SRC=$(SRC)
+	$(CC) $(CFLAGS) $? -o $@

dir-locals.el

@@ -0,0 +1 @@
+((c-mode . ((compile-command . "make -C ../build -j2 whatever"))))

src/board.h

@@ -27,7 +27,10 @@ typedef struct {
  */
 #define SQ88(f, r)   (16 * (r) + (f))             /* from rank,file to sq88 */
 #define FILE88(s)    ((s) & 7)                    /* from sq88 to file */
-#define RANK88(s)    ((s) >> 8)                   /* from sq88 to rank */
+#define RANK88(s)    ((s) >> 4)                   /* from sq88 to rank */
+
+#define SQ88_NOK(s)  ((s) & 0x88)                 /* invalid square */
+#define SQ88_OK(s)   (!SQ88_NOK(s))
 
 /* piece human notation
  */

src/move.c

@@ -0,0 +1,222 @@
+/* move.c - move management.
+ *
+ * Copyright (C) 2021 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.htmlL>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#include <malloc.h>
+#include <ctype.h>
+#include "chessdefs.h"
+#include "piece.h"
+#include "move.h"
+#include "list.h"
+
+static pool_t *moves_pool;
+
+static struct vector {
+    unsigned char ndirs;
+    char slide;
+    char dir[8];
+} vectors[] = {
+    [KNIGHT] = { 8, 0, { -33, -31, -18, -14, 14, 18, 31, 33}},
+    [BISHOP] = { 4, 1, { -15, -17, 15, 17}},
+    [ROOK]   = { 4, 1, { -1, -16, 1, 16}},
+    [QUEEN] =  { 8, 1, { -1, -16, 1, 16, -15, -17, 15, 17}},
+    [KING] =   { 8, 0, { -1, -16, 1, 16, -15, -17, 15, 17}},
+};
+
+inline static char piece2char(piece_t p)
+{
+    piece_t piece = PIECE(p);
+    char res;
+
+    //printf("%#x p=%#x\n", p, PIECE(p));
+    switch (piece) {
+        case PAWN:
+            res = CHAR_PAWN;
+            break;
+        case KNIGHT:
+            res = CHAR_KNIGHT;
+            break;
+        case BISHOP:
+            res = CHAR_BISHOP;
+            break;
+        case ROOK:
+            res = CHAR_ROOK;
+            break;
+        case QUEEN:
+            res = CHAR_QUEEN;
+            break;
+        case KING:
+            res = CHAR_KING;
+            break;
+        default:
+            res = CHAR_EMPTY;
+    }
+    return res;
+
+}
+
+pool_t *moves_pool_init()
+{
+    if (!moves_pool)
+        moves_pool = pool_init("moves", 128, sizeof(piece_list_t));
+    return moves_pool;
+}
+
+
+
+void move_print(move_t *move)
+{
+    printf("%c%c%c", piece2char(move->piece),
+           FILE2C(GET_F(move->from)),
+           RANK2C(GET_R(move->from)));
+    if (move->taken)
+        printf("x%c", piece2char(move->taken));
+    else
+        printf("-");
+    printf("%c%c",
+           FILE2C(GET_F(move->to)),
+           RANK2C(GET_R(move->to)));
+    printf(" ");
+}
+
+void moves_print(pos_t *pos)
+{
+    struct list_head *p_cur, *tmp;
+    move_t *move;
+    int i = 0;
+
+    printf("%s pseudo-moves: ", pos->turn == WHITE? "White": "Black");
+    list_for_each_safe(p_cur, tmp, &pos->moves) {
+        move = list_entry(p_cur, move_t, list);
+
+        move_print(move);
+        i++;
+    }
+    printf("Total moves = %d\n", i);
+}
+
+/* generate moves for non pawn pieces
+ */
+int pseudo_moves_get(pos_t *pos, piece_list_t *ppiece)
+{
+    piece_t piece = PIECE(ppiece->piece);
+    struct vector *vector = vectors+piece;
+    square_t square = ppiece->square;
+    unsigned char ndirs = vector->ndirs;
+    char slide = vector->slide;
+    board_t *board = pos->board;
+    char color = COLOR(piece);
+    move_t *move;
+    int count = 0;
+
+    /*printf("%s: pos:%p piece:%d [%s] at %#04x[%c%c]\n", __func__, pos, piece,
+           piece2string(piece),
+           square,
+           FILE2C(GET_F(square)),
+           RANK2C(GET_R(square)));
+    printf("\tvector=%ld ndirs=%d slide=%d\n", vector-vectors, ndirs, slide);
+    */
+    for (int curdir = 0; curdir < ndirs; ++curdir) {
+        char dir = vector->dir[curdir];
+        for (square_t new = square + dir; ; new = new + dir) {
+            /* outside board */
+            if (SQ88_NOK(new)) {
+                //printf("\t\tskipping %04x (invalid square)\n", new);
+                break;
+            }
+            //printf("\ttrying %c%c", FILE2C(GET_F(new)), RANK2C(GET_R(new)));
+            /* own color on dest square */
+            if (board[new].piece && COLOR(board[new].piece) == color) {
+                //printf("\t\tskipping %04x (same color piece)\n", new);
+                break;
+            }
+
+            /* we are sure the move is valid : we create move */
+            if (!(move = pool_get(moves_pool))) {
+                //printf("\t\tmem error\n");
+                return count;
+            }
+            move->piece = piece;
+            move->from = square;
+            move->to = new;
+            move->taken = board[new].piece;
+            //move_print(move);
+            list_add(&move->list, &pos->moves);
+            count++;
+            if (move->taken)
+                break;
+            if (!slide)
+                break;
+        }
+    }
+    return count;
+}
+
+int moves_get(pos_t *pos)
+{
+    struct list_head *p_cur, *tmp, *piece_list;
+    piece_list_t *piece;
+    int count = 0;
+
+    piece_list = pos->turn == WHITE? &pos->pieces_white: &pos->pieces_black;
+
+    list_for_each_safe(p_cur, tmp, piece_list) {
+        piece = list_entry(p_cur, piece_list_t, list);
+        if (PIECE(piece->piece) != PAWN)
+            pseudo_moves_get(pos, piece);
+
+        count++;
+    }
+    return count;
+}
+
+move_t *pseudo_moves_pawn(pos_t *pos)
+{
+    static short directions[] = {16};
+    if (!pos && *directions)
+        printf("for flycheck");
+    return NULL;
+}
+
+/* unused
+move_t *(*moves_fct[])(pos_t *) = {
+    [PAWN] = pseudo_moves_pawn,
+    [KNIGHT] = pseudo_moves_knight,
+    [BISHOP] = pseudo_moves_bishop,
+    [ROOK] = pseudo_moves_rook,
+    [QUEEN] = pseudo_moves_queen,
+    [KING] = pseudo_moves_king
+};
+*/
+
+#ifdef MOVEBIN
+#include "fen.h"
+int main(int ac, char**av)
+{
+    pos_t *pos;
+
+    pos = pos_create();
+    piece_pool_init();
+    moves_pool_init();
+
+
+    if (ac == 1) {
+        pos_startpos(pos);
+    } else {
+        fen2pos(pos, av[1]);
+    }
+    pos_print(pos);
+    pieces_print_pos_pieces(pos);
+    moves_get(pos);
+    moves_print(pos);
+}
+#endif

src/move.h

@@ -16,12 +16,24 @@
 
 #include "chessdefs.h"
 #include "position.h"
+#include "pool.h"
+#include "piece.h"
 
-typedef struct {
-    piece_t t;
+typedef struct move_s {
+    piece_t piece;
     square_t from, to;
-} MOVE;
+    piece_t taken;                                /* removed piece */
 
-extern MOVE *moves_rook(POS *pos);
+    struct list_head list;
+} move_t;
+
+pool_t *moves_pool_init();
+void move_print(move_t *move);
+void moves_print(pos_t *move);
+int pseudo_moves_get(pos_t *pos, piece_list_t *piece);
+int moves_get(pos_t *pos);
+
+/* not used */
+move_t *pseudo_moves_pawn(pos_t *pos);
 
 #endif

src/piece.c

@@ -14,9 +14,42 @@
 #include <malloc.h>
 #include "chessdefs.h"
 #include "piece.h"
+#include "ctype.h"
 
 static pool_t *pieces_pool;
 
+inline static char piece2char(piece_t p)
+{
+    piece_t piece = PIECE(p);
+    char res;
+
+    //printf("%#x p=%#x\n", p, PIECE(p));
+    switch (piece) {
+        case PAWN:
+            res = CHAR_PAWN;
+            break;
+        case KNIGHT:
+            res = CHAR_KNIGHT;
+            break;
+        case BISHOP:
+            res = CHAR_BISHOP;
+            break;
+        case ROOK:
+            res = CHAR_ROOK;
+            break;
+        case QUEEN:
+            res = CHAR_QUEEN;
+            break;
+        case KING:
+            res = CHAR_KING;
+            break;
+        default:
+            res = CHAR_EMPTY;
+    }
+    return res;
+
+}
+
 void piece_list_print(struct list_head *list)
 {
     struct list_head *p_cur, *tmp;
@@ -26,7 +59,7 @@ void piece_list_print(struct list_head *list)
     list_for_each_safe(p_cur, tmp, list) {
         piece = list_entry(p_cur, piece_list_t, list);
 
-        printf("%c%c%c ", *piece2string(piece->piece),
+        printf("%c%c%c ", piece2char(piece->piece),
                FILE2C(GET_F(piece->square)),
                RANK2C(GET_R(piece->square)));
         /*printf("\t%d: %s on %c%c\n", i,

src/position.c

@@ -145,6 +145,7 @@ pos_t *pos_init(pos_t *pos)
     pos->en_passant = 0;
     INIT_LIST_HEAD(&pos->pieces_white);
     INIT_LIST_HEAD(&pos->pieces_black);
+    INIT_LIST_HEAD(&pos->moves);
 
     return pos;
 }

src/position.h

@@ -28,6 +28,7 @@ typedef struct position {
     eval_t eval;
     struct list_head pieces_white;
     struct list_head pieces_black;
+    struct list_head moves;
     board_t *board;
 } pos_t;