threads / patch / 52859

patchrun-command.c: ensure signaled hook scripts are waited upon

Subject: [PATCH] run-command.c: ensure signaled hook scripts are waited upon

## tl;dr

3 messages between Feb 21, 2020 and Feb 22, 2020. Diffs are folded; open one to read it.

replies: 2people: 3as markdown or json

Anthony Sottile· Feb 21, 2020, 06:06 UTC · lore

In the event of a `^C` while hook scripts are running, ensure that the hook processes are cleaned up and do not become zombies. This also ensures that upon `^C` execution is not handed back to the terminal until the processes have been waited upon.

Signed-off-by: Anthony Sottile <asottile@umich.edu>
---
 run-command.c | 2 ++
 1 file changed, 2 insertions(+)

Show changes to run-command.c +2 −0

diff --git a/run-command.c b/run-command.c
index f5e1149..75d3b73 100644
--- a/run-command.c
+++ b/run-command.c
@@ -1358,6 +1358,8 @@ int run_hook_ve(const char *const *env, const char *name, va_list args)
 	hook.no_stdin = 1;
 	hook.stdout_to_stderr = 1;
 	hook.trace2_hook_name = name;
+	hook.clean_on_exit = 1;
+	hook.wait_after_clean = 1;
 
 	return run_command(&hook);
 }

-- 
2.25.GIT

Jeff King· Feb 21, 2020, 06:39 UTC · re: Anthony Sottile · lore

Re: [PATCH] run-command.c: ensure signaled hook scripts are waited upon

On Thu, Feb 20, 2020 at 10:06:36PM -0800, Anthony Sottile wrote:

> In the event of a `^C` while hook scripts are running, ensure that the
> hook processes are cleaned up and do not become zombies.  This also ensures
> that upon `^C` execution is not handed back to the terminal until the
> processes have been waited upon.

If we assume that most people would prefer this "wait until the hook has died" behavior, I think this shouldn't have any unwanted secondary effects. I'm on the fence on whether it's what most people would want or not (I guess most people don't care either way, because their scripts don't ignore SIGINT).

(Earlier in the thread, we discussed possibly swapping the order of the cleanup code and dropping the signal handler, which could have more unexpected effects, but that part isn't in this patch).

-Peff

Junio C Hamano· Feb 22, 2020, 17:12 UTC · re: Jeff King · lore

Re: [PATCH] run-command.c: ensure signaled hook scripts are waited upon

Jeff King <peff@peff.net> writes:

Show 5 quoted lines

> If we assume that most people would prefer this "wait until the hook has
> died" behavior, I think this shouldn't have any unwanted secondary
> effects. I'm on the fence on whether it's what most people would want or
> not (I guess most people don't care either way, because their scripts
> don't ignore SIGINT).

Yeah, and imagining why they deliberately ignore INT (i.e. "because I want this hook not be interrupted and run to its completion") does not help guess if they want git to wait for hook's completion or just go ahead and die of its own signal death. We could timeout the waiting and kill such a child forcibly, and that may avoid these hook script that ignore INT to hang around, but I do not know if that is desirable.