+static int handle_one_ref(const char *path,
+ const unsigned char *sha1, int flag, void *cb_data)
+{
+ struct commit_list **list = cb_data;
+ struct object *object = parse_object(sha1);
+ if (!object)
+ return 0;
+ if (object->type == OBJ_TAG)
+ object = deref_tag(object, path, strlen(path));
+ if (object->type != OBJ_COMMIT)
+ return 0;
+ insert_by_date((struct commit *)object, list);
+ return 0;
+}
+
+/*
+ * This interprets names like ':/Initial revision of "git"' by searching
+ * through history and returning the first commit whose message starts
+ * with the given string.
+ *
+ * For future extension, ':/!' is reserved. If you want to match a message
+ * beginning with a '!', you have to repeat the exclamation mark.
+ */
+
+#define ONELINE_SEEN (1u<<20)
+static int get_sha1_oneline(const char *prefix, unsigned char *sha1)
+{
+ struct commit_list *list = NULL, *backup = NULL, *l;
+ int retval = -1;
+
+ if (prefix[0] == '!') {
+ if (prefix[1] != '!')
+ die ("Invalid search pattern: %s", prefix);
+ prefix++;
+ }
+ if (!save_commit_buffer)
+ return error("Could not expand oneline-name.");
+ for_each_ref(handle_one_ref, &list);
+ for (l = list; l; l = l->next)
+ commit_list_insert(l->item, &backup);
+ while (list) {
+ char *p;
+ struct commit *commit;
+
+ commit = pop_most_recent_commit(&list, ONELINE_SEEN);
+ parse_object(commit->object.sha1);
+ if (!commit->buffer || !(p = strstr(commit->buffer, "\n\n")))
+ continue;
+ if (!prefixcmp(p + 2, prefix)) {
+ hashcpy(sha1, commit->object.sha1);
+ retval = 0;
+ break;
+ }
+ }
+ free_commit_list(list);
+ for (l = backup; l; l = l->next)
+ clear_commit_marks(l->item, ONELINE_SEEN);
+ return retval;
+}
+