Do not pass board around

Instead use the get_board() function to get a reference to the board.

6 files changed, 47 insertions, 46 deletions

diff --git a/cmd/main.c b/cmd/main.c
index 8b3e521..e751856 100644
--- a/cmd/main.c
+++ b/cmd/main.c
@@ -28,10 +28,8 @@
 int main(int argc, char **argv) {
   (void)argc;
   (void)argv;
-  enum player_color board[8][8];
-  initialize_board(board);
 
-  enum player_color winner = game_loop(board);
+  enum player_color winner = game_loop();
 
   switch (winner) {
   case WHITE:
@@ -45,7 +43,7 @@ int main(int argc, char **argv) {
   }
 
   puts("Here was the final board:");
-  print_board(board);
+  print_board();
 
   return EXIT_SUCCESS;
 }
diff --git a/include/othello.h b/include/othello.h
index e6c7796..acf09a0 100644
--- a/include/othello.h
+++ b/include/othello.h
@@ -40,24 +40,22 @@ extern struct move (*player_two_get_move)(enum player_color board[8][8],
                                           enum player_color current_player);
 
 // Set a board to a new game state.
-void initialize_board(enum player_color board[8][8]);
+void initialize_board(enum player_color ***board);
 
 // True if move is valid for current_player.
 // Otherwise false.
-bool is_valid_move(enum player_color board[8][8],
-                   const enum player_color current_player,
+bool is_valid_move(const enum player_color current_player,
                    const struct move move);
 
 // True if current_player has any valid moves.
 // Otherwise false.
-bool has_valid_moves(enum player_color board[8][8],
-                     const enum player_color current_player);
+bool has_valid_moves(const enum player_color current_player);
 
 // Plays a game to completion, starting with board.
-enum player_color game_loop(enum player_color board[8][8]);
+enum player_color game_loop(void);
 
 // Prints the current state of the board, including coordinates in the margins.
-void print_board(enum player_color board[8][8]);
+void print_board(void);
 
 // Returns the color of the player whose turn it is.
 enum player_color get_current_player(void);
diff --git a/src/game_loop.c b/src/game_loop.c
index 4674e44..c11f473 100644
--- a/src/game_loop.c
+++ b/src/game_loop.c
@@ -31,10 +31,18 @@
 
 #define STREQ(a, b) (strcmp(a, b) == 0)
 
-struct move (*player_one_get_move)(enum player_color board[8][8],
-                                   enum player_color current_player);
-struct move (*player_two_get_move)(enum player_color board[8][8],
-                                   enum player_color current_player);
+static enum player_color current_player;
+
+enum player_color get_current_player(void) { return current_player; }
+
+static enum player_color **board;
+
+const enum player_color **get_board(void) {
+  return (const enum player_color **)board;
+}
+
+struct move (*player_one_get_move)();
+struct move (*player_two_get_move)();
 
 static enum player_color other_player(enum player_color current_player) {
   switch (current_player) {
@@ -76,8 +84,7 @@ static void inner_main(void *closure, int argc, char **argv) {
   scm_shell(argc, argv);
 }
 
-static struct move prompt_get_move(enum player_color board[8][8],
-                                   enum player_color current_player) {
+static struct move prompt_get_move(enum player_color current_player) {
   // Initialize move to an invalid move.
   struct move move = {-1, -1};
 
@@ -90,7 +97,7 @@ static struct move prompt_get_move(enum player_color board[8][8],
       if (STREQ(input, "h")) {
         print_help();
       } else if (STREQ(input, "p")) {
-        print_board(board);
+        print_board();
       } else if (STREQ(input, "g")) {
         int argc = 1;
         char **argv = calloc(1, sizeof(char *));
@@ -108,14 +115,13 @@ static struct move prompt_get_move(enum player_color board[8][8],
     }
 
     free(input);
-  } while (!is_valid_move(board, current_player, move));
+  } while (!is_valid_move(current_player, move));
 
   return move;
 }
 
 /* Returns true if the move was valid */
-static bool apply_move(enum player_color board[8][8],
-                       enum player_color current_player, struct move move) {
+static bool apply_move(enum player_color current_player, struct move move) {
 
   // Flip in up direction
   bool flipped_up = false;
@@ -168,24 +174,16 @@ static bool apply_move(enum player_color board[8][8],
   return flipped_up || flipped_down || flipped_left || flipped_right;
 }
 
-static enum player_color current_player;
-
-enum player_color get_current_player(void) { return current_player; }
-
-static enum player_color board[8][8];
-
-const enum player_color **get_board(void) {
-  return (const enum player_color **)board;
-}
 
-enum player_color game_loop(enum player_color init_board[8][8]) {
+enum player_color game_loop() {
+  initialize_board(&board);
   using_history();
 
   current_player = WHITE;
 
-  while (has_valid_moves(board, current_player)) {
-    struct move move = prompt_get_move(board, current_player);
-    apply_move(board, current_player, move);
+  while (has_valid_moves(current_player)) {
+    struct move move = prompt_get_move(current_player);
+    apply_move(current_player, move);
     current_player = other_player(current_player);
   }
 
diff --git a/src/initialize_board.c b/src/initialize_board.c
index 2e037c3..18b1468 100644
--- a/src/initialize_board.c
+++ b/src/initialize_board.c
@@ -18,20 +18,26 @@
 
 #define _GNU_SOURCE
 
+#include <stdlib.h>
+
 #include "othello.h"
 
-void initialize_board(enum player_color board[8][8]) {
+void initialize_board(enum player_color ***board) {
+  *board = malloc(8 * sizeof(enum player_color *));
+  for (int i = 0; i < 8; i++) {
+      (*board)[i] = malloc(8 * sizeof(enum player_color));
+  }
 
   // Set all the positions to empty
   for (int i = 0; i < 8; i++) {
     for (int j = 0; j < 8; j++) {
-      board[i][j] = EMPTY;
+      (*board)[i][j] = EMPTY;
     }
   }
 
   // Fill the starting positions
-  board[3][3] = WHITE;
-  board[3][4] = BLACK;
-  board[4][3] = BLACK;
-  board[4][4] = WHITE;
+  (*board)[3][3] = WHITE;
+  (*board)[3][4] = BLACK;
+  (*board)[4][3] = BLACK;
+  (*board)[4][4] = WHITE;
 }
diff --git a/src/print_board.c b/src/print_board.c
index 4256e7e..98280fd 100644
--- a/src/print_board.c
+++ b/src/print_board.c
@@ -22,7 +22,9 @@
 
 #include "othello.h"
 
-void print_board(enum player_color board[8][8]) {
+void print_board() {
+  const enum player_color **board = get_board();
+
   puts("  0 1 2 3 4 5 6 7");
 
   for (int row = 0; row < 8; row++) {
diff --git a/src/valid_moves.c b/src/valid_moves.c
index d37de3c..bd53833 100644
--- a/src/valid_moves.c
+++ b/src/valid_moves.c
@@ -22,9 +22,9 @@
 
 #include "othello.h"
 
-bool is_valid_move(enum player_color board[8][8],
-                   const enum player_color current_player,
+bool is_valid_move(const enum player_color current_player,
                    const struct move move) {
+  const enum player_color **board = get_board();
   // The move must be a positive position.
   if (move.row < 0 || move.col < 0) {
     return false;
@@ -81,13 +81,12 @@ bool is_valid_move(enum player_color board[8][8],
   return is_valid_up || is_valid_down || is_valid_left || is_valid_right;
 }
 
-bool has_valid_moves(enum player_color board[8][8],
-                     const enum player_color current_player) {
+bool has_valid_moves(const enum player_color current_player) {
   bool result = false;
   struct move move;
   for (move.row = 0; move.row < 8 && !result; move.row++) {
     for (move.col = 0; move.col < 8 && !result; move.col++) {
-      result = is_valid_move(board, current_player, move);
+      result = is_valid_move(current_player, move);
     }
   }