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 --- 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); } -- 2.31.0

On 4/7/21 6:47 AM, 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.

The entire point of SIGQUIT is to let users kill a program in such a way that it produces a coredump. "You can think of this as a program error condition 'detected' by the user." I'm curious how one might accidentally do this.

Signed-off-by: ZheNing Hu --- 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); }

-- Eli Schwartz Bug Wrangler and Trusted User