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| | #include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/wait.h>
#include <spawn.h>
#include <errno.h>
#include "pthread_impl.h"
#include "libc.h"
static void dummy_0()
{
}
weak_alias(dummy_0, __acquire_ptc);
weak_alias(dummy_0, __release_ptc);
extern char **__environ;
int system(const char *cmd)
{
pid_t pid;
sigset_t old, reset;
struct sigaction sa = { .sa_handler = SIG_IGN }, oldint, oldquit;
int status = 0x7f00, ret;
posix_spawnattr_t attr;
pthread_testcancel();
if (!cmd) return 1;
sigaction(SIGINT, &sa, &oldint);
sigaction(SIGQUIT, &sa, &oldquit);
sigaddset(&sa.sa_mask, SIGCHLD);
sigprocmask(SIG_BLOCK, &sa.sa_mask, &old);
sigemptyset(&reset);
if (oldint.sa_handler != SIG_IGN) sigaddset(&reset, SIGINT);
if (oldquit.sa_handler != SIG_IGN) sigaddset(&reset, SIGQUIT);
posix_spawnattr_init(&attr);
posix_spawnattr_setsigmask(&attr, &old);
posix_spawnattr_setsigdefault(&attr, &reset);
posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSIGDEF|POSIX_SPAWN_SETSIGMASK);
ret = posix_spawn(&pid, "/bin/sh", 0, &attr,
(char *[]){"sh", "-c", (char *)cmd, 0}, __environ);
posix_spawnattr_destroy(&attr);
if (!ret) while (waitpid(pid, &status, 0)<0 && errno == EINTR);
sigaction(SIGINT, &oldint, NULL);
sigaction(SIGQUIT, &oldquit, NULL);
sigprocmask(SIG_SETMASK, &old, NULL);
if (ret) errno = ret;
return status;
}
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