- if (!base)
- die("failed to read delta base object"
- " at %"PRIuMAX" from %s",
- (uintmax_t)base_offset, p->pack_name);
+ if (!base) {
+ /*
+ * We're probably in deep shit, but let's try to fetch
+ * the required base anyway from another pack or loose.
+ * This is costly but should happen only in the presence
+ * of a corrupted pack, and is better than failing outright.
+ */
+ struct revindex_entry *revidx = find_pack_revindex(p, base_offset);
+ const unsigned char *base_sha1 =
+ nth_packed_object_sha1(p, revidx->nr);
+ error("failed to read delta base object %s"
+ " at offset %"PRIuMAX" from %s",
+ sha1_to_hex(base_sha1), (uintmax_t)base_offset,
+ p->pack_name);
+ mark_bad_packed_object(p, base_sha1);
+ base = read_object(base_sha1, type, &base_size);
+ if (!base)
+ return NULL;
+ }