+static game_state *solve_game(game_state *state, game_aux_info *ai,
+ char **error)
+{
+ game_state *ret;
+
+ ret = dup_game(state);
+ ret->completed = ret->cheated = TRUE;
+
+ /*
+ * If we already have the solved state in an aux_info, copy it
+ * out.
+ */
+ if (ai) {
+
+ assert(ret->w == ai->w);
+ assert(ret->h == ai->h);
+ memcpy(ret->grid, ai->grid, ai->w * ai->h);
+
+ } else {
+ int w = state->w, h = state->h, i, j, done_any, max;
+ unsigned char *matrix, *workspace;
+ int *rowdata;
+
+ matrix = snewn(w*h, unsigned char);
+ max = max(w, h);
+ workspace = snewn(max*3, unsigned char);
+ rowdata = snewn(max+1, int);
+
+ memset(matrix, 0, w*h);
+
+ do {
+ done_any = 0;
+ for (i=0; i<h; i++) {
+ memcpy(rowdata, state->rowdata + state->rowsize*(w+i),
+ max*sizeof(int));
+ rowdata[state->rowlen[w+i]] = 0;
+ done_any |= do_row(workspace, workspace+max, workspace+2*max,
+ matrix+i*w, w, 1, rowdata);
+ }
+ for (i=0; i<w; i++) {
+ memcpy(rowdata, state->rowdata + state->rowsize*i, max*sizeof(int));
+ rowdata[state->rowlen[i]] = 0;
+ done_any |= do_row(workspace, workspace+max, workspace+2*max,
+ matrix+i, h, w, rowdata);
+ }
+ } while (done_any);
+
+ for (i = 0; i < h; i++) {
+ for (j = 0; j < w; j++) {
+ int c = (matrix[i*w+j] == BLOCK ? GRID_FULL :
+ matrix[i*w+j] == DOT ? GRID_EMPTY : GRID_UNKNOWN);
+ ret->grid[i*w+j] = c;
+ if (c == GRID_UNKNOWN)
+ ret->completed = FALSE;
+ }
+ }
+
+ if (!ret->completed) {
+ free_game(ret);
+ *error = "Solving algorithm cannot complete this puzzle";
+ return NULL;
+ }
+ }
+
+ return ret;
+}
+
+static char *game_text_format(game_state *state)
+{
+ return NULL;
+}
+