cosmopolitan/libc/calls/pipe2.c
Justine Tunney 3f0bcdc3ef
Improve cancellations, randomness, and time
- Exhaustively document cancellation points
- Rename SIGCANCEL to SIGTHR just like BSDs
- Further improve POSIX thread cancellations
- Ensure asynchronous cancellations work correctly
- Elevate the quality of getrandom() and getentropy()
- Make futexes cancel correctly on OpenBSD 6.x and 7.x
- Add reboot.com and shutdown.com to examples directory
- Remove underscore prefix from awesome timespec_*() APIs
- Create assertions that help verify our cancellation points
- Remove bad timespec APIs (cmp generalizes eq/ne/gt/gte/lt/lte)
2022-11-05 23:45:32 -07:00

54 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 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/syscall-nt.internal.h"
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/errfuns.h"
/**
* Creates file-less file descriptors for interprocess communication.
*
* @raise EMFILE if process `RLIMIT_NOFILE` has been reached
* @raise ENFILE if system-wide file limit has been reached
* @param pipefd is used to return (reader, writer) file descriptors
* @param flags can have O_CLOEXEC or O_DIRECT or O_NONBLOCK
* @return 0 on success, or -1 w/ errno and pipefd isn't modified
*/
int pipe2(int pipefd[hasatleast 2], int flags) {
int rc;
if (flags & ~(O_CLOEXEC | O_NONBLOCK | O_DIRECT)) {
return einval();
} else if (!pipefd ||
(IsAsan() && !__asan_is_valid(pipefd, sizeof(int) * 2))) {
rc = efault();
} else if (!IsWindows()) {
rc = sys_pipe2(pipefd, flags);
} else {
rc = sys_pipe_nt(pipefd, flags);
}
if (!rc) {
STRACE("pipe2([{%d, %d}], %#o) → %d% m", pipefd[0], pipefd[1], flags, rc);
} else {
STRACE("pipe2(%p, %#o) → %d% m", pipefd, flags, rc);
}
return rc;
}