cosmopolitan/libc/calls/ucontext.c
Justine Tunney e961385e55
Put more thought into i/o polyfills
wait4() is now solid enough to run `make -j100` on Windows. You can now
use MSG_DONTWAIT on Windows. There was a handle leak in accept() that's
been fixed. Our WIN32 overlapped i/o code has been simplified. Priority
class now inherits into subprocesses, so the verynice command will work
and the signal mask will now be inherited by execve() and posix_spawn()
2023-11-07 18:32:35 -08:00

64 lines
3 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 2023 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/ucontext.h"
#include "libc/calls/struct/sigset.internal.h"
#include "libc/dce.h"
#include "libc/intrin/atomic.h"
#include "libc/sysv/consts/sig.h"
#include "libc/thread/tls.h"
int __tailcontext(const ucontext_t *);
/**
* Sets machine context.
*
* @return -1 on error w/ errno, otherwise won't return unless sent back
* @see swapcontext()
* @see makecontext()
* @see getcontext()
*/
int setcontext(const ucontext_t *uc) {
if (IsWindows()) {
atomic_store_explicit(&__get_tls()->tib_sigmask, uc->uc_sigmask,
memory_order_release);
} else {
sys_sigprocmask(SIG_SETMASK, &uc->uc_sigmask, 0);
}
return __tailcontext(uc);
}
int __getcontextsig(ucontext_t *uc) {
if (IsWindows()) {
uc->uc_sigmask =
atomic_load_explicit(&__get_tls()->tib_sigmask, memory_order_acquire);
return 0;
} else {
return sys_sigprocmask(SIG_SETMASK, 0, &uc->uc_sigmask);
}
}
int __swapcontextsig(ucontext_t *x, const ucontext_t *y) {
if (IsWindows()) {
x->uc_sigmask = atomic_exchange_explicit(
&__get_tls()->tib_sigmask, y->uc_sigmask, memory_order_acquire);
return 0;
} else {
return sys_sigprocmask(SIG_SETMASK, &y->uc_sigmask, &x->uc_sigmask);
}
}