Cleaned up execute_move a little

diff --git a/towers.c b/towers.c
index 011a4068bf63ba001f046f6619a95bb64a10f267..2b9e4e7ba4690ee8086ed2e39123f4bcc0c861a9 100644 (file)
--- a/towers.c
+++ b/towers.c
@@ -1391,35 +1391,29 @@ static char *interpret_move(const game_state *state, game_ui *ui,
 static game_state *execute_move(const game_state *from, const char *move)
 {
     int w = from->par.w, a = w*w;
-    game_state *ret;
+    game_state *ret = dup_game(from);
     int x, y, i, n;
 
     if (move[0] == 'S') {
-       ret = dup_game(from);
        ret->completed = ret->cheated = TRUE;
 
        for (i = 0; i < a; i++) {
-           if (move[i+1] < '1' || move[i+1] > '0'+w) {
-               free_game(ret);
-               return NULL;
-           }
+            if (move[i+1] < '1' || move[i+1] > '0'+w)
+                goto badmove;
            ret->grid[i] = move[i+1] - '0';
            ret->pencil[i] = 0;
        }
 
-       if (move[a+1] != '\0') {
-           free_game(ret);
-           return NULL;
-       }
+        if (move[a+1] != '\0')
+            goto badmove;
 
        return ret;
     } else if ((move[0] == 'P' || move[0] == 'R') &&
        sscanf(move+1, "%d,%d,%d", &x, &y, &n) == 3 &&
        x >= 0 && x < w && y >= 0 && y < w && n >= 0 && n <= w) {
        if (from->clues->immutable[y*w+x])
-           return NULL;
+            goto badmove;
 
-       ret = dup_game(from);
         if (move[0] == 'P' && n > 0) {
             ret->pencil[y*w+x] ^= 1L << n;
         } else {
@@ -1437,14 +1431,17 @@ static game_state *execute_move(const game_state *from, const char *move)
         * starting point when following through a set of
         * diagnostics output by the standalone solver.)
         */
-       ret = dup_game(from);
        for (i = 0; i < a; i++) {
            if (!ret->grid[i])
                ret->pencil[i] = (1L << (w+1)) - (1L << 1);
        }
        return ret;
-    } else
-       return NULL;                   /* couldn't parse move string */
+    }
+
+  badmove:
+    /* couldn't parse move string */
+    free_game(ret);
+    return NULL;
 }
 
 /* ----------------------------------------------------------------------