+void (*report_garbage)(const char *desc, const char *path);
+
+static void report_helper(const struct string_list *list,
+ int seen_bits, int first, int last)
+{
+ const char *msg;
+ switch (seen_bits) {
+ case 0:
+ msg = "no corresponding .idx nor .pack";
+ break;
+ case 1:
+ msg = "no corresponding .idx";
+ break;
+ case 2:
+ msg = "no corresponding .pack";
+ break;
+ default:
+ return;
+ }
+ for (; first < last; first++)
+ report_garbage(msg, list->items[first].string);
+}
+
+static void report_pack_garbage(struct string_list *list)
+{
+ int i, baselen = -1, first = 0, seen_bits = 0;
+
+ if (!report_garbage)
+ return;
+
+ sort_string_list(list);
+
+ for (i = 0; i < list->nr; i++) {
+ const char *path = list->items[i].string;
+ if (baselen != -1 &&
+ strncmp(path, list->items[first].string, baselen)) {
+ report_helper(list, seen_bits, first, i);
+ baselen = -1;
+ seen_bits = 0;
+ }
+ if (baselen == -1) {
+ const char *dot = strrchr(path, '.');
+ if (!dot) {
+ report_garbage("garbage found", path);
+ continue;
+ }
+ baselen = dot - path + 1;
+ first = i;
+ }
+ if (!strcmp(path + baselen, "pack"))
+ seen_bits |= 1;
+ else if (!strcmp(path + baselen, "idx"))
+ seen_bits |= 2;
+ }
+ report_helper(list, seen_bits, first, list->nr);
+}
+