[pacman-dev] [PATCH 1/1] signhandler: add SIGQUIT soft_interrupt_handler

[Allan McRae]

On 7/4/21 8:47 pm, ZheNing Hu wrote:
> When we downloading with pacman. If we want to
> stop downloading, use `Ctrl +C` can exit normally,
> and "Interrupt signal received" will be print
> on the terminal. But if we accidentally use
> `Ctrl + \` to exit the download, it's not quite
> so perfect. The program exits with a segment
> fault, the database lock file was not deleted
> in time. The next time we use pacman downloading,
> the error will appear.
> 
> So we can add signal handler with SIGQUIT, just
> like we did with SIGINT and SIGHUP. This way the
> user doesn't have to delete lock file manually.
> 
> Signed-off-by: ZheNing Hu <adlternative at gmail.com>
> ---

>From the glibc manual:

"Certain kinds of cleanups are best omitted in handling SIGQUIT. For
example, if the program creates temporary files, it should handle the
other termination requests by deleting the temporary files. But it is
better for SIGQUIT not to delete them, so that the user can examine them
in conjunction with the core dump. "

https://www.gnu.org/software/libc/manual/html_node/Termination-Signals.html


>  src/pacman/sighandler.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/src/pacman/sighandler.c b/src/pacman/sighandler.c
> index ff54dce8..9fdbf917 100644
> --- a/src/pacman/sighandler.c
> +++ b/src/pacman/sighandler.c
> @@ -81,15 +81,18 @@ void install_soft_interrupt_handler(void)
>  	new_action.sa_flags = SA_RESTART;
>  	sigemptyset(&new_action.sa_mask);
>  	sigaddset(&new_action.sa_mask, SIGINT);
> +	sigaddset(&new_action.sa_mask, SIGQUIT);
>  	sigaddset(&new_action.sa_mask, SIGHUP);
>  
>  	sigaction(SIGINT, &new_action, NULL);
> +	sigaction(SIGQUIT, &new_action, NULL);
>  	sigaction(SIGHUP, &new_action, NULL);
>  }
>  
>  void remove_soft_interrupt_handler(void)
>  {
>  	_reset_handler(SIGINT);
> +	_reset_handler(SIGQUIT);
>  	_reset_handler(SIGHUP);
>  }
>  
>