fetch-pack: implement ref-in-want

diff --git a/fetch-pack.c b/fetch-pack.c
index 73890b8943595b2fe31a5b56cd390539ed26c23e..0b4a9f288f973a13ab8c55b420d52143ee1d026d 100644 (file)
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -1102,9 +1102,10 @@ static void add_shallow_requests(struct strbuf *req_buf,
 
 static void add_wants(const struct ref *wants, struct strbuf *req_buf)
 {
+       int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0);
+
        for ( ; wants ; wants = wants->next) {
                const struct object_id *remote = &wants->old_oid;
-               const char *remote_hex;
                struct object *o;
 
                /*
@@ -1122,8 +1123,10 @@ static void add_wants(const struct ref *wants, struct strbuf *req_buf)
                        continue;
                }
 
-               remote_hex = oid_to_hex(remote);
-               packet_buf_write(req_buf, "want %s\n", remote_hex);
+               if (!use_ref_in_want || wants->exact_oid)
+                       packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote));
+               else
+                       packet_buf_write(req_buf, "want-ref %s\n", wants->name);
        }
 }
 
@@ -1334,6 +1337,32 @@ static void receive_shallow_info(struct fetch_pack_args *args,
        args->deepen = 1;
 }
 
+static void receive_wanted_refs(struct packet_reader *reader, struct ref *refs)
+{
+       process_section_header(reader, "wanted-refs", 0);
+       while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
+               struct object_id oid;
+               const char *end;
+               struct ref *r = NULL;
+
+               if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
+                       die("expected wanted-ref, got '%s'", reader->line);
+
+               for (r = refs; r; r = r->next) {
+                       if (!strcmp(end, r->name)) {
+                               oidcpy(&r->old_oid, &oid);
+                               break;
+                       }
+               }
+
+               if (!r)
+                       die("unexpected wanted-ref: '%s'", reader->line);
+       }
+
+       if (reader->status != PACKET_READ_DELIM)
+               die("error processing wanted refs: %d", reader->status);
+}
+
 enum fetch_state {
        FETCH_CHECK_LOCAL = 0,
        FETCH_SEND_REQUEST,
@@ -1408,6 +1437,9 @@ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
                        if (process_section_header(&reader, "shallow-info", 1))
                                receive_shallow_info(args, &reader);
 
+                       if (process_section_header(&reader, "wanted-refs", 1))
+                               receive_wanted_refs(&reader, ref);
+
                        /* get the pack */
                        process_section_header(&reader, "packfile", 0);
                        if (get_pack(args, fd, pack_lockfile))