cosmopolitan/libc/calls/sigsuspend.c
Justine Tunney 6f7d0cb1c3
Pay off more technical debt
This makes breaking changes to add underscores to many non-standard
function names provided by the c library. MODE=tiny is now tinier and
we now use smaller locks that are better for tiny apps in this mode.
Some headers have been renamed to be in the same folder as the build
package, so it'll be easier to know which build dependency is needed.
Certain old misguided interfaces have been removed. Intel intrinsics
headers are now listed in libc/isystem (but not in the amalgamation)
to help further improve open source compatibility. Header complexity
has also been reduced. Lastly, more shell scripts are now available.
2022-09-12 23:36:56 -07:00

100 lines
4.2 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/calls/sig.internal.h"
#include "libc/calls/struct/sigset.h"
#include "libc/calls/struct/sigset.internal.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/describeflags.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/log/backtrace.internal.h"
#include "libc/nt/errors.h"
#include "libc/nt/synchronization.h"
#include "libc/sysv/consts/sig.h"
#include "libc/sysv/errfuns.h"
/**
* Blocks until SIG ∉ MASK is delivered to process.
*
* This temporarily replaces the signal mask until a signal that it
* doesn't contain is delivered.
*
* @param ignore is a bitset of signals to block temporarily, which if
* NULL is equivalent to passing an empty signal set
* @return -1 w/ EINTR (or possibly EFAULT)
* @asyncsignalsafe
* @norestart
*/
int sigsuspend(const sigset_t *ignore) {
int rc;
long ms, totoms;
sigset_t save, mask, *arg;
STRACE("sigsuspend(%s) → ...", DescribeSigset(0, ignore));
if (IsAsan() && ignore && !__asan_is_valid(ignore, sizeof(*ignore))) {
rc = efault();
} else if (IsXnu() || IsOpenbsd()) {
// openbsd and xnu only support 32 signals
// they use a register calling convention for sigsuspend
if (ignore) {
arg = (sigset_t *)(uintptr_t)(*(uint32_t *)ignore);
} else {
arg = 0;
}
rc = sys_sigsuspend(arg, 8);
} else if (IsLinux() || IsFreebsd() || IsNetbsd() || IsWindows()) {
if (ignore) {
arg = ignore;
} else {
sigemptyset(&mask);
arg = &mask;
}
if (!IsWindows()) {
rc = sys_sigsuspend(arg, 8);
} else {
__sig_mask(SIG_SETMASK, arg, &save);
ms = 0;
totoms = 0;
do {
if (_check_interrupts(false, g_fds.p)) {
rc = eintr();
break;
}
if (SleepEx(__SIG_POLLING_INTERVAL_MS, true) == kNtWaitIoCompletion) {
POLLTRACE("IOCP EINTR");
continue;
}
#if defined(SYSDEBUG) && defined(_POLLTRACE)
ms += __SIG_POLLING_INTERVAL_MS;
if (ms >= __SIG_LOGGING_INTERVAL_MS) {
totoms += ms, ms = 0;
POLLTRACE("... sigsuspending for %'lums...", totoms);
}
#endif
} while (1);
__sig_mask(SIG_SETMASK, &save, 0);
}
} else {
// TODO(jart): sigsuspend metal support
rc = enosys();
}
STRACE("...sigsuspend → %d% m", rc);
return rc;
}