cosmopolitan/libc/stdio/system.c
Justine Tunney 18bb5888e1
Make more fixes and improvements
- Remove PAGESIZE constant
- Fix realloc() documentation
- Fix ttyname_r() error reporting
- Make forking more reliable on Windows
- Make execvp() a few microseconds faster
- Make system() a few microseconds faster
- Tighten up the socket-related magic numbers
- Loosen restrictions on mmap() offset alignment
- Improve GetProgramExecutableName() with getenv("_")
- Use mkstemp() as basis for mktemp(), tmpfile(), tmpfd()
- Fix flakes in pthread_cancel_test, unix_test, fork_test
- Fix recently introduced futex stack overflow regression
- Let sockets be passed as stdio to subprocesses on Windows
- Improve security of bind() on Windows w/ SO_EXCLUSIVEADDRUSE
2023-07-29 18:44:15 -07:00

80 lines
3.6 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/blockcancel.internal.h"
#include "libc/calls/calls.h"
#include "libc/calls/struct/rusage.h"
#include "libc/calls/struct/sigaction.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/intrin/weaken.h"
#include "libc/log/log.h"
#include "libc/paths.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/ok.h"
#include "libc/sysv/consts/sig.h"
#include "libc/thread/thread.h"
/**
* Launches program with system command interpreter.
*
* This embeds the Cosmopolitan Command Interpreter which provides
* Bourne-like syntax on all platforms including Windows.
*
* @param cmdline is a unix shell script
* @return -1 if child process couldn't be created, otherwise a wait
* status that can be accessed using macros like WEXITSTATUS(s),
* WIFSIGNALED(s), WTERMSIG(s), etc.
* @threadsafe
*/
int system(const char *cmdline) {
int pid, wstatus;
sigset_t chldmask, savemask;
if (!cmdline) return 1;
BLOCK_CANCELLATIONS;
sigemptyset(&chldmask);
sigaddset(&chldmask, SIGINT);
sigaddset(&chldmask, SIGQUIT);
sigaddset(&chldmask, SIGCHLD);
sigprocmask(SIG_BLOCK, &chldmask, &savemask);
if (!(pid = fork())) {
sigprocmask(SIG_SETMASK, &savemask, 0);
_Exit(_cocmd(3, (char *[]){"system", "-c", cmdline, 0}, environ));
} else if (pid == -1) {
wstatus = -1;
} else {
struct sigaction ignore, saveint, savequit;
ignore.sa_flags = 0;
ignore.sa_handler = SIG_IGN;
sigemptyset(&ignore.sa_mask);
sigaction(SIGINT, &ignore, &saveint);
sigaction(SIGQUIT, &ignore, &savequit);
while (wait4(pid, &wstatus, 0, 0) == -1) {
if (errno != EINTR) {
wstatus = -1;
break;
}
}
sigaction(SIGINT, &saveint, 0);
sigaction(SIGQUIT, &savequit, 0);
}
sigprocmask(SIG_SETMASK, &savemask, 0);
ALLOW_CANCELLATIONS;
return wstatus;
}