+static game_state *solve_game(game_state *state, game_aux_info *aux,
+ char **error)
+{
+ game_state *ret;
+ int c = state->c, r = state->r;
+ int rsolve_ret;
+
+ /*
+ * I could have stored the grid I invented in the game_aux_info
+ * and extracted it here where available, but it seems easier
+ * just to run my internal solver in all cases.
+ */
+
+ ret = dup_game(state);
+ ret->completed = ret->cheated = TRUE;
+
+ rsolve_ret = rsolve(c, r, ret->grid, NULL, 2);
+
+ if (rsolve_ret != 1) {
+ free_game(ret);
+ if (rsolve_ret == 0)
+ *error = "No solution exists for this puzzle";
+ else
+ *error = "Multiple solutions exist for this puzzle";
+ return NULL;
+ }
+
+ return ret;
+}
+