implement fetching of moved submodules

diff --git a/refs/iterator.c b/refs/iterator.c
index c475360f0a8c6bc5aa26876f8fd8d2ca5ebc3ebd..bd35da4e622ca4016194177ce97594b46c5aafe7 100644 (file)
--- a/refs/iterator.c
+++ b/refs/iterator.c
@@ -287,6 +287,20 @@ struct prefix_ref_iterator {
        int trim;
 };
 
+/* Return -1, 0, 1 if refname is before, inside, or after the prefix. */
+static int compare_prefix(const char *refname, const char *prefix)
+{
+       while (*prefix) {
+               if (*refname != *prefix)
+                       return ((unsigned char)*refname < (unsigned char)*prefix) ? -1 : +1;
+
+               refname++;
+               prefix++;
+       }
+
+       return 0;
+}
+
 static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
 {
        struct prefix_ref_iterator *iter =
@@ -294,9 +308,25 @@ static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
        int ok;
 
        while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) {
-               if (!starts_with(iter->iter0->refname, iter->prefix))
+               int cmp = compare_prefix(iter->iter0->refname, iter->prefix);
+
+               if (cmp < 0)
                        continue;
 
+               if (cmp > 0) {
+                       /*
+                        * If the source iterator is ordered, then we
+                        * can stop the iteration as soon as we see a
+                        * refname that comes after the prefix:
+                        */
+                       if (iter->iter0->ordered) {
+                               ok = ref_iterator_abort(iter->iter0);
+                               break;
+                       } else {
+                               continue;
+                       }
+               }
+
                if (iter->trim) {
                        /*
                         * It is nonsense to trim off characters that