[PATCH v4] receive-pack: check if client is alive before completing the push
- From
- Robin Jarry <robin.jarry@6wind.com>
- Date
- Jan 28, 2022, 19:48 UTC
- Message-ID
- <20220128194811.3396281-1-robin.jarry@6wind.com>
- In-Reply-To
- <20220127215553.1386024-1-robin.jarry@6wind.com>
Abort the push operation (i.e. do not migrate the objects from temporary to permanent storage) if the client has disconnected while the pre-receive hook was running.
This reduces the risk of inconsistencies on network errors or if the user hits ctrl-c while the pre-receive hook is running.
Send a keepalive packet (empty) on sideband 2 (the one to report progress). If the client has exited the write() operation should fail and the push will be aborted. This only works when sideband* capabilities are advertised by the client.
Note: if the write() operation fails, receive-pack will likely be killed via SIGPIPE and even so, since the client is likely gone already, the error strings will go nowhere. I only added them for code consistency.
Signed-off-by: Robin Jarry <robin.jarry@6wind.com> --- v3 -> v4: - reworded the comment block s/ensure/notice/ - used write_in_full() instead of write_or_die() - set error_string fields for code consistency
builtin/receive-pack.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index 9f4a0b816cf9..f8b9a9312733 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -1971,6 +1971,22 @@ static void execute_commands(struct command *commands, return; } + /* + * Send a keepalive packet on sideband 2 (progress info) to notice + * a client that has disconnected (e.g. killed with ^C) while + * pre-receive was running. + */ + if (use_sideband) { + static const char buf[] = "0005\2"; + if (write_in_full(1, buf, sizeof(buf) - 1) < 0) { + for (cmd = commands; cmd; cmd = cmd->next) { + if (!cmd->error_string) + cmd->error_string = "pusher went away"; + } + return; + } + } + /* * Now we'll start writing out refs, which means the objects need * to be in their final positions so that other processes can see them.
-- 2.35.0.4.g44a5d4affccf