upload-pack: add a trigger for post-upload-pack hook

After upload-pack successfully finishes its operation, post-upload-pack
hook can be called for logging purposes.

The hook is passed various pieces of information, one per line, from its
standard input.  Currently the following items can be fed to the hook, but
more types of information may be added in the future:

    want SHA-1::
        40-byte hexadecimal object name the client asked to include in the
        resulting pack.  Can occur one or more times in the input.

    have SHA-1::
        40-byte hexadecimal object name the client asked to exclude from
        the resulting pack, claiming to have them already.  Can occur zero
        or more times in the input.

    time float::
        Number of seconds spent for creating the packfile.

    size decimal::
        Size of the resulting packfile in bytes.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 68 insertions, 2 deletions

diff --git a/upload-pack.c b/upload-pack.c
index 4d8be834ff..857440d579 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -141,8 +141,62 @@ static int do_rev_list(int fd, void *create_full_pack)
 	return 0;
 }
 
+static int feed_msg_to_hook(int fd, const char *fmt, ...)
+{
+	int cnt;
+	char buf[1024];
+	va_list params;
+
+	va_start(params, fmt);
+	cnt = vsprintf(buf, fmt, params);
+	va_end(params);
+	return write_in_full(fd, buf, cnt) != cnt;
+}
+
+static int feed_obj_to_hook(const char *label, struct object_array *oa, int i, int fd)
+{
+	return feed_msg_to_hook(fd, "%s %s\n", label,
+				sha1_to_hex(oa->objects[i].item->sha1));
+}
+
+static int run_post_upload_pack_hook(size_t total, struct timeval *tv)
+{
+	const char *argv[2];
+	struct child_process proc;
+	int err, i;
+
+	argv[0] = "hooks/post-upload-pack";
+	argv[1] = NULL;
+
+	if (access(argv[0], X_OK) < 0)
+		return 0;
+
+	memset(&proc, 0, sizeof(proc));
+	proc.argv = argv;
+	proc.in = -1;
+	proc.stdout_to_stderr = 1;
+	err = start_command(&proc);
+	if (err)
+		return err;
+	for (i = 0; !err && i < want_obj.nr; i++)
+		err |= feed_obj_to_hook("want", &want_obj, i, proc.in);
+	for (i = 0; !err && i < have_obj.nr; i++)
+		err |= feed_obj_to_hook("have", &have_obj, i, proc.in);
+	if (!err)
+		err |= feed_msg_to_hook(proc.in, "time %ld.%06ld\n",
+					(long)tv->tv_sec, (long)tv->tv_usec);
+	if (!err)
+		err |= feed_msg_to_hook(proc.in, "size %ld\n", (long)total);
+	if (close(proc.in))
+		err = 1;
+	if (finish_command(&proc))
+		err = 1;
+	return err;
+}
+
 static void create_pack_file(void)
 {
+	struct timeval start_tv, tv;
 	struct async rev_list;
 	struct child_process pack_objects;
 	int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
@@ -150,10 +204,12 @@ static void create_pack_file(void)
 	char abort_msg[] = "aborting due to possible repository "
 		"corruption on the remote side.";
 	int buffered = -1;
-	ssize_t sz;
+	ssize_t sz, total_sz;
 	const char *argv[10];
 	int arg = 0;
 
+	gettimeofday(&start_tv, NULL);
+	total_sz = 0;
 	if (shallow_nr) {
 		rev_list.proc = do_rev_list;
 		rev_list.data = 0;
@@ -262,7 +318,7 @@ static void create_pack_file(void)
 			sz = xread(pack_objects.out, cp,
 				  sizeof(data) - outsz);
 			if (0 < sz)
-					;
+				total_sz += sz;
 			else if (sz == 0) {
 				close(pack_objects.out);
 				pack_objects.out = -1;
@@ -314,6 +370,16 @@ static void create_pack_file(void)
 	}
 	if (use_sideband)
 		packet_flush(1);
+
+	gettimeofday(&tv, NULL);
+	tv.tv_sec -= start_tv.tv_sec;
+	if (tv.tv_usec < start_tv.tv_usec) {
+		tv.tv_sec--;
+		tv.tv_usec += 1000000;
+	}
+	tv.tv_usec -= start_tv.tv_usec;
+	if (run_post_upload_pack_hook(total_sz, &tv))
+		warning("post-upload-hook failed");
 	return;
 
  fail: