Allow for having for_each_ref() list extra refs

These refs can be anything, but they are most likely useful as
pointing to objects that you know are in the object database but don't
have any regular refs for. For example, when cloning with --reference,
the refs in this repository should be listed as objects that we have,
even though we don't have refs in our newly-created repository for
them yet.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/refs.c b/refs.c
index 4db73ed8f0..8300cc1b54 100644
--- a/refs.c
+++ b/refs.c
@@ -159,6 +159,8 @@ static struct cached_refs {
 } cached_refs;
 static struct ref_list *current_ref;
 
+static struct ref_list *extra_refs;
+
 static void free_ref_list(struct ref_list *list)
 {
 	struct ref_list *next;
@@ -215,6 +217,17 @@ static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
 	cached_refs->packed = sort_ref_list(list);
 }
 
+void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
+{
+	extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
+}
+
+void clear_extra_refs(void)
+{
+	free_ref_list(extra_refs);
+	extra_refs = NULL;
+}
+
 static struct ref_list *get_packed_refs(void)
 {
 	if (!cached_refs.did_packed) {
@@ -536,6 +549,11 @@ static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
 	struct ref_list *packed = get_packed_refs();
 	struct ref_list *loose = get_loose_refs();
 
+	struct ref_list *extra;
+
+	for (extra = extra_refs; extra; extra = extra->next)
+		retval = do_one_ref(base, fn, trim, cb_data, extra);
+
 	while (packed && loose) {
 		struct ref_list *entry;
 		int cmp = strcmp(packed->name, loose->name);