Refactor

include/common.h

@@ -0,0 +1,26 @@
+
+#include <stdbool.h> /* true, false, bool */
+#include <stddef.h>  /* ptrdiff_t */
+#include <stdint.h>  /* int32_t */
+
+/** Type representing piece/tile on a chessboard */
+typedef int32_t tile_t;
+
+/** Type representing index of a chessboard tile */
+typedef ptrdiff_t index_t;
+
+#define BOARD_SIZE ((index_t)(8 * 8))
+
+#define WHITE 1
+#define BLACK -1
+
+#define E ((tile_t)0) ///< empty tile
+#define K ((tile_t)1) ///< king
+#define Q ((tile_t)2) ///< queen
+#define R ((tile_t)3) ///< rook
+#define B ((tile_t)4) ///< bishop
+#define N ((tile_t)5) ///< knight
+#define P ((tile_t)6) ///< pawn
+
+#define ROW ((index_t)8)
+#define COL ((index_t)1)

include/graphics.h

@@ -0,0 +1,8 @@
+#ifndef GRAPHICS_H
+#define GRAPHICS_H
+
+#include "common.h"
+
+void print_board(const tile_t board[BOARD_SIZE]);
+
+#endif

include/pieces.h

@@ -0,0 +1,12 @@
+
+#ifndef PIECES_H
+#define PIECES_H
+
+#include "common.h"
+
+bool move_ok(const tile_t board[BOARD_SIZE],
+             index_t      from,
+             index_t      to,
+             int    player);
+
+#endif

include/util.h

@@ -0,0 +1,9 @@
+#include "common.h"
+
+bool    tile_empty(tile_t t);
+index_t abs_pos(index_t p);
+index_t column(index_t i);
+index_t row(index_t i);
+tile_t  abs_tile(tile_t t);
+bool    same_color(tile_t a, tile_t b);
+bool    opposite_color(tile_t a, tile_t b);