+ } while ((dst = dst->next) != NULL);
+ return renames;
+}
+
+static void free_similarity_list(struct file_similarity *p)
+{
+ while (p) {
+ struct file_similarity *entry = p;
+ p = p->next;
+ free(entry);
+ }
+}
+
+static int find_same_files(void *ptr)
+{
+ int ret;
+ struct file_similarity *p = ptr;
+ struct file_similarity *src = NULL, *dst = NULL;
+
+ /* Split the hash list up into sources and destinations */
+ do {
+ struct file_similarity *entry = p;
+ p = p->next;
+ if (entry->src_dst < 0) {
+ entry->next = src;
+ src = entry;
+ } else {
+ entry->next = dst;
+ dst = entry;
+ }
+ } while (p);
+
+ /*
+ * If we have both sources *and* destinations, see if
+ * we can match them up
+ */
+ ret = (src && dst) ? find_identical_files(src, dst) : 0;
+
+ /* Free the hashes and return the number of renames found */
+ free_similarity_list(src);
+ free_similarity_list(dst);
+ return ret;
+}
+
+static unsigned int hash_filespec(struct diff_filespec *filespec)
+{
+ unsigned int hash;
+ if (!filespec->sha1_valid) {
+ if (diff_populate_filespec(filespec, 0))
+ return 0;
+ hash_sha1_file(filespec->data, filespec->size, "blob", filespec->sha1);
+ }
+ memcpy(&hash, filespec->sha1, sizeof(hash));
+ return hash;
+}
+
+static void insert_file_table(struct hash_table *table, int src_dst, int index, struct diff_filespec *filespec)
+{
+ void **pos;
+ unsigned int hash;
+ struct file_similarity *entry = xmalloc(sizeof(*entry));
+
+ entry->src_dst = src_dst;
+ entry->index = index;
+ entry->filespec = filespec;
+ entry->next = NULL;
+
+ hash = hash_filespec(filespec);
+ pos = insert_hash(hash, entry, table);
+
+ /* We already had an entry there? */
+ if (pos) {
+ entry->next = *pos;
+ *pos = entry;