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#include <spawn.h>
#include <unistd.h>
#include <signal.h>
#include <stdint.h>
#include <fcntl.h>
#include "syscall.h"
#include "fdop.h"
extern char **environ;
int __posix_spawnx(pid_t *restrict res, const char *restrict path,
int (*exec)(const char *, char *const *),
const posix_spawn_file_actions_t *fa,
const posix_spawnattr_t *restrict attr,
char *const argv[restrict], char *const envp[restrict])
{
pid_t pid;
sigset_t oldmask;
int i;
posix_spawnattr_t dummy_attr = { 0 };
if (!attr) attr = &dummy_attr;
sigprocmask(SIG_BLOCK, (void *)(uint64_t []){-1}, &oldmask);
pid = __syscall(SYS_fork);
if (pid) {
sigprocmask(SIG_SETMASK, &oldmask, 0);
if (pid < 0) return -pid;
*res = pid;
return 0;
}
for (i=1; i<=64; i++) {
struct sigaction sa;
sigaction(i, 0, &sa);
if (sa.sa_handler!=SIG_IGN ||
((attr->__flags & POSIX_SPAWN_SETSIGDEF)
&& sigismember(&attr->__def, i) )) {
sa.sa_handler = SIG_DFL;
sigaction(i, &sa, 0);
}
}
if ((attr->__flags&POSIX_SPAWN_SETPGROUP) && setpgid(0, attr->__pgrp))
_exit(127);
/* Use syscalls directly because pthread state is not consistent
* for making calls to the library wrappers... */
if ((attr->__flags&POSIX_SPAWN_RESETIDS) && (
__syscall(SYS_setgid, __syscall(SYS_getgid)) ||
__syscall(SYS_setuid, __syscall(SYS_getuid)) ))
_exit(127);
if (fa && fa->__actions) {
struct fdop *op;
int ret, fd;
for (op = fa->__actions; op->next; op = op->next);
for (; op; op = op->prev) {
switch(op->cmd) {
case FDOP_CLOSE:
ret = __syscall(SYS_close, op->fd);
break;
case FDOP_DUP2:
ret = __syscall(SYS_dup2, op->fd, op->newfd)<0;
break;
case FDOP_OPEN:
fd = __syscall(SYS_open, op->path,
op->oflag | O_LARGEFILE, op->mode);
if (fd == op->fd) {
ret = 0;
} else {
ret = __syscall(SYS_dup2, fd, op->fd)<0;
__syscall(SYS_close, fd);
}
break;
}
if (ret) _exit(127);
}
}
sigprocmask(SIG_SETMASK, (attr->__flags & POSIX_SPAWN_SETSIGMASK)
? &attr->__mask : &oldmask, 0);
if (envp) environ = (char **)envp;
exec(path, argv);
_exit(127);
return 0;
}
int posix_spawn(pid_t *restrict res, const char *restrict path,
const posix_spawn_file_actions_t *fa,
const posix_spawnattr_t *restrict attr,
char *const argv[restrict], char *const envp[restrict])
{
return __posix_spawnx(res, path, execv, fa, attr, argv, envp);
}
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