New capability "report-status-v2" for git-push

The new introduced "proc-receive" hook may handle a command for a
pseudo-reference with a zero-old as its old-oid, while the hook may
create or update a reference with different name, different new-oid,
and different old-oid (the reference may exist already with a non-zero
old-oid).  Current "report-status" protocol cannot report the status for
such reference rewrite.

Add new capability "report-status-v2" and new report protocol which is
not backward compatible for report of git-push.

If a user pushes to a pseudo-reference "refs/for/master/topic", and
"receive-pack" creates two new references "refs/changes/23/123/1" and
"refs/changes/24/124/1", for client without the knowledge of
"report-status-v2", "receive-pack" will only send "ok/ng" directives in
the report, such as:

    ok ref/for/master/topic

But for client which has the knowledge of "report-status-v2",
"receive-pack" will use "option" directives to report more attributes
for the reference given by the above "ok/ng" directive.

    ok refs/for/master/topic
    option refname refs/changes/23/123/1
    option new-oid <new-oid>
    ok refs/for/master/topic
    option refname refs/changes/24/124/1
    option new-oid <new-oid>

The client will report two new created references to the end user.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/builtin/send-pack.c b/builtin/send-pack.c
index f2c5a34402..2777cc4371 100644
--- a/builtin/send-pack.c
+++ b/builtin/send-pack.c
@@ -29,10 +29,12 @@ static struct send_pack_args args;
 static void print_helper_status(struct ref *ref)
 {
 	struct strbuf buf = STRBUF_INIT;
+	struct ref_push_report *report;
 
 	for (; ref; ref = ref->next) {
 		const char *msg = NULL;
 		const char *res;
+		int count = 0;
 
 		switch(ref->status) {
 		case REF_STATUS_NONE:
@@ -94,6 +96,23 @@ static void print_helper_status(struct ref *ref)
 		}
 		strbuf_addch(&buf, '\n');
 
+		if (ref->status == REF_STATUS_OK) {
+			for (report = ref->report; report; report = report->next) {
+				if (count++ > 0)
+					strbuf_addf(&buf, "ok %s\n", ref->name);
+				if (report->ref_name)
+					strbuf_addf(&buf, "option refname %s\n",
+						report->ref_name);
+				if (report->old_oid)
+					strbuf_addf(&buf, "option old-oid %s\n",
+						oid_to_hex(report->old_oid));
+				if (report->new_oid)
+					strbuf_addf(&buf, "option new-oid %s\n",
+						oid_to_hex(report->new_oid));
+				if (report->forced_update)
+					strbuf_addstr(&buf, "option forced-update\n");
+			}
+		}
 		write_or_die(1, buf.buf, buf.len);
 	}
 	strbuf_release(&buf);