fetch-pack: support negotiation tip whitelist
During negotiation, fetch-pack eventually reports as "have" lines all
commits reachable from all refs. Allow the user to restrict the commits
sent in this way by providing a whitelist of tips; only the tips
themselves and their ancestors will be sent.
Both globs and single objects are supported.
This feature is only supported for protocols that support connect or
stateless-connect (such as HTTP with protocol v2).
This will speed up negotiation when the repository has multiple
relatively independent branches (for example, when a repository
interacts with multiple repositories, such as with linux-next [1] and
torvalds/linux [2]), and the user knows which local branch is likely to
have commits in common with the upstream branch they are fetching.
[1] https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next/
[2] https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux/
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/fetch.c b/builtin/fetch.c
index ea5b966..49ab6ac 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -63,6 +63,7 @@ static int shown_url = 0;
static struct refspec refmap = REFSPEC_INIT_FETCH;
static struct list_objects_filter_options filter_options;
static struct string_list server_options = STRING_LIST_INIT_DUP;
+static struct string_list negotiation_tip = STRING_LIST_INIT_NODUP;
static int git_fetch_config(const char *k, const char *v, void *cb)
{
@@ -174,6 +175,8 @@ static struct option builtin_fetch_options[] = {
TRANSPORT_FAMILY_IPV4),
OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
TRANSPORT_FAMILY_IPV6),
+ OPT_STRING_LIST(0, "negotiation-tip", &negotiation_tip, N_("revision"),
+ N_("report that we have only objects reachable from this object")),
OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
OPT_END()
};
@@ -1049,6 +1052,40 @@ static void set_option(struct transport *transport, const char *name, const char
name, transport->url);
}
+
+static int add_oid(const char *refname, const struct object_id *oid, int flags,
+ void *cb_data)
+{
+ struct oid_array *oids = cb_data;
+
+ oid_array_append(oids, oid);
+ return 0;
+}
+
+static void add_negotiation_tips(struct git_transport_options *smart_options)
+{
+ struct oid_array *oids = xcalloc(1, sizeof(*oids));
+ int i;
+
+ for (i = 0; i < negotiation_tip.nr; i++) {
+ const char *s = negotiation_tip.items[i].string;
+ int old_nr;
+ if (!has_glob_specials(s)) {
+ struct object_id oid;
+ if (get_oid(s, &oid))
+ die("%s is not a valid object", s);
+ oid_array_append(oids, &oid);
+ continue;
+ }
+ old_nr = oids->nr;
+ for_each_glob_ref(add_oid, s, oids);
+ if (old_nr == oids->nr)
+ warning("Ignoring --negotiation-tip=%s because it does not match any refs",
+ s);
+ }
+ smart_options->negotiation_tips = oids;
+}
+
static struct transport *prepare_transport(struct remote *remote, int deepen)
{
struct transport *transport;
@@ -1075,6 +1112,12 @@ static struct transport *prepare_transport(struct remote *remote, int deepen)
filter_options.filter_spec);
set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
}
+ if (negotiation_tip.nr) {
+ if (transport->smart_options)
+ add_negotiation_tips(transport->smart_options);
+ else
+ warning("Ignoring --negotiation-tip because the protocol does not support it.");
+ }
return transport;
}
