Hi Jon, On Jul 17 12:58, Jon Turney wrote: > On 13/07/2023 12:38, Jon Turney wrote: > > > > cancel11: some funkiness I can't work out, causing the save/restoring > > signal handlers around system() to not > > work correctly > > So, the test here: is the SIGINT handle restored correctly if the thread > executing system() is cancelled. This test fails, because it's not. > > It seems like that scenario was explicitly considered when this test was > added in https://cygwin.com/pipermail/cygwin-patches/2003q1/003378.html > > I think maybe this is a regression introduced in > https://cygwin.com/cgit/newlib-cygwin/commit/?id=3cb9da14617c58c2821c80d48f0bd80a2deb5fdf > > child_info_spawn::worker calls waitpid() which ultimately calls cygwait() > which notices the thread's cancel event is signalled and acts as a > cancellation point. > > Attached is a patch which adds back the restoration of signal handlers on > thread cancellation. > > I can't find any hints in the mailing lists around 2013-04 about what > problem that change is fixing, but given the commentary, this might be > reintroducing another problem, though.
Maybe, but the patch is slim enough so we might get away with it. > From a798750d271e20402a0a5efc4ac073f5948ad5b7 Mon Sep 17 00:00:00 2001 > From: Jon Turney <jon.tur...@dronecode.org.uk> > Date: Sun, 16 Jul 2023 14:46:00 +0100 > Subject: [PATCH] Cygwin: Restore pthread cleanup of signal handlers during > system() > > Removed in 3cb9da14 which describes it as 'ill-advised' (additional > context doesn't appear to be available). Actually, "ill-conceived". Beats my why, though. > We can't neatly tuck the pthread_cleanup_push/pop inside the object, as > they are implemented as macros which must appear in the same lexical > scope. You could do it if you call the underlying functions instead. pthread_cleanup_push is just a convenience macro which initializes a local __pthread_cleanup_handler, see include/pthread.h. If you add a __pthread_cleanup_handler to system_call_handle, you could use it the same way as the macro and encapsulate the whole thing inside the object. If you want to... Fixes and Signed-off-by tags? Thanks, Corinna
