[PATCH stable] chg: forward SIGWINCH to worker

[Jun Wu]

I notice that setupsignalhandler() can be cleaned up a bit (remove
duplicated "sa.sa_flags = SA_RESTART;", "sa.sa_handler = forwardsignal;"
and add a comment for SIGHUP, SIGINT, besides, explain why handlestopsignal
is used instead of just forwardsignal).

I will do that after the freeze.

On 04/17/2016 12:22 AM, Jun Wu wrote:
> # HG changeset patch
> # User Jun Wu <quark at fb.com>
> # Date 1460248132 -3600
> #      Sun Apr 10 01:28:52 2016 +0100
> # Node ID 9e798e2ead7cc52a8a199d2ef89cf05fc6af5645
> # Parent  7b008530793234393f512275ebca12df4d9fd394
> chg: forward SIGWINCH to worker
>
> Before this patch, if the user uses chg and ncurses interface, resizing the
> terminal window will mess up its content.
>
> This patch fixes the issue by forwarding SIGWINCH to the worker process.
>
> diff --git a/contrib/chg/chg.c b/contrib/chg/chg.c
> --- a/contrib/chg/chg.c
> +++ b/contrib/chg/chg.c
> @@ -397,6 +397,10 @@
>   	if (sigaction(SIGTERM, &sa, NULL) < 0)
>   		goto error;
>
> +	/* notify the worker about window resize events */
> +	sa.sa_flags = SA_RESTART;
> +	if (sigaction(SIGWINCH, &sa, NULL) < 0)
> +		goto error;
>   	/* propagate job control requests to worker */
>   	sa.sa_handler = forwardsignal;
>   	sa.sa_flags = SA_RESTART;