Robin Jarry <robin.jarry@xxxxxxxxx> writes:
> 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, receive-pack will be killed via
> SIGPIPE and the push will be aborted. This only works when sideband*
> capabilities are advertised by the client.
>
> Signed-off-by: Robin Jarry <robin.jarry@xxxxxxxxx>
> ---
> v2 -> v3:
> I had missed Documentation/technical/pack-protocol.txt. Using
> sideband 2 to send the keepalive packet works.
Yes, as long as sideband capability is supported (which is true
everywhere these days), this would be good.
Simple and sensible.
Thanks.
> builtin/receive-pack.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
> index 9f4a0b816cf9..8b0d56897c9f 100644
> --- a/builtin/receive-pack.c
> +++ b/builtin/receive-pack.c
> @@ -1971,6 +1971,15 @@ static void execute_commands(struct command *commands,
> return;
> }
>
> + /*
> + * Send a keepalive packet on sideband 2 (progress info) to ensure that
> + * the client has not disconnected while pre-receive was running.
> + */
> + if (use_sideband) {
> + static const char buf[] = "0005\2";
> + write_or_die(1, buf, sizeof(buf) - 1);
> + }
> +
> /*
> * 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.
