diff options
| author | Matthew Bauer <mjbauer95@gmail.com> | 2022-09-03 00:27:16 -0500 |
|---|---|---|
| committer | Matthew Bauer <mjbauer95@gmail.com> | 2022-09-03 00:27:16 -0500 |
| commit | 102434e4cbb8ed1b4075f99fb999f092fa068d5b (patch) | |
| tree | 2132cf66739f3b554d360e0862926d237166694a /src/libmain/shared.cc | |
| parent | 0c7f213c87c11c6c0f6b2fa07ba96548f6ea85ad (diff) | |
Disable SA_RESTART for some signals on macOS
Disables the SA_RESTART behavior on macOS which causes:
> Restarting of pending calls is requested by setting the SA_RESTART bit
> in sa_flags. The affected system calls include read(2), write(2),
> sendto(2), recvfrom(2), sendmsg(2) and recvmsg(2) on a communications
> channel or a slow device (such as a terminal, but not a regular file)
> and during a wait(2) or ioctl(2).
From: https://man.openbsd.org/sigaction#SA_RESTART
This being set on macOS caused a bug where read() calls to the daemon
socket were blocking after a SIGINT was received. As a result,
checkInterrupt was never reached even though the signal was received
by the signal handler thread.
On Linux, SA_RESTART is disabled by default. This probably effects
other BSDs but I don’t have the ability to test it there right now.
Diffstat (limited to 'src/libmain/shared.cc')
| -rw-r--r-- | src/libmain/shared.cc | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/src/libmain/shared.cc b/src/libmain/shared.cc index 31454e49d..0ee3fe772 100644 --- a/src/libmain/shared.cc +++ b/src/libmain/shared.cc @@ -194,9 +194,16 @@ void initNix() /* HACK: on darwin, we need can’t use sigprocmask with SIGWINCH. * Instead, add a dummy sigaction handler, and signalHandlerThread * can handle the rest. */ - struct sigaction sa; - sa.sa_handler = sigHandler; - if (sigaction(SIGWINCH, &sa, 0)) throw SysError("handling SIGWINCH"); + act.sa_handler = sigHandler; + if (sigaction(SIGWINCH, &act, 0)) throw SysError("handling SIGWINCH"); + + // Disable SA_RESTART for interrupts, so that system calls on this thread + // error with EINTR like they do on Linux, and we don’t hang forever. + act.sa_handler = SIG_DFL; + if (sigaction(SIGINT, &act, 0)) throw SysError("handling SIGINT"); + if (sigaction(SIGTERM, &act, 0)) throw SysError("handling SIGTERM"); + if (sigaction(SIGHUP, &act, 0)) throw SysError("handling SIGHUP"); + if (sigaction(SIGPIPE, &act, 0)) throw SysError("handling SIGPIPE"); #endif /* Register a SIGSEGV handler to detect stack overflows. */ |