[RFC PATCH] receive-pack: run post-receive before reporting status
- From
- Robin Jarry <robin.jarry@6wind.com>
- Date
- Nov 4, 2021, 13:35 UTC
- Message-ID
- <20211104133546.1967308-1-robin.jarry@6wind.com>
When a remote client exits while the pre-receive hook is running, receive-pack is not killed by SIGPIPE because the signal is ignored. This is a side effect of commit ec7dbd145bd8 ("receive-pack: allow hooks to ignore its standard input stream").
The pre-receive hook is not interrupted and does not receive any error since its stdout is a pipe which is read in an async thread and output back to the client socket in a side band channel. When writing the data in the socket, the async thread gets a SIGPIPE which also seems ignored. This may be a race between the main and the async threads. I do not know the code well enough to be sure.
After the pre-receive has exited the SIGPIPE default handler is restored and if the hook did not report any error, objects are migrated from temporary to permanent storage.
Before running the post-receive hook, status info is reported back to the client. Since the client has died, receive-pack is killed by SIGPIPE and post-receive is never executed.
The post-receive hook is often used to send email notifications (see contrib/hooks/post-receive-email), update bug trackers, start automatic builds, etc. Not executing it after an interrupted yet "successful" push can lead to inconsistencies.
Execute the post-receive hook before reporting status to the client to avoid this issue. This is not an ideal solution but I don't know if allowing hooks to be killed when a client exits is a good idea. Maybe for pre-receive but definitely not for post-receive.
Signed-off-by: Robin Jarry <robin.jarry@6wind.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> --- builtin/receive-pack.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index 49b846d96052..df8bedf71319 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -2564,14 +2564,14 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix) use_keepalive = KEEPALIVE_ALWAYS; execute_commands(commands, unpack_status, &si, &push_options); + run_receive_hook(commands, "post-receive", 1, + &push_options); if (pack_lockfile) unlink_or_warn(pack_lockfile); if (report_status_v2) report_v2(commands, unpack_status); else if (report_status) report(commands, unpack_status); - run_receive_hook(commands, "post-receive", 1, - &push_options); run_update_post_hook(commands); string_list_clear(&push_options, 0); if (auto_gc) {
-- 2.30.2