147 lines
3.7 KiB
C
147 lines
3.7 KiB
C
/* Copyright (C) 1991, 1992, 1994, 1995 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If
|
|
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
|
|
Cambridge, MA 02139, USA. */
|
|
|
|
#include <ansidecl.h>
|
|
#include <stddef.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <sys/wait.h>
|
|
#include <signal.h>
|
|
#include <sys/types.h>
|
|
#include <errno.h>
|
|
|
|
|
|
#ifndef HAVE_GNU_LD
|
|
#define __environ environ
|
|
#endif
|
|
|
|
#define SHELL_PATH "/bin/sh" /* Path of the shell. */
|
|
#define SHELL_NAME "sh" /* Name to give it. */
|
|
|
|
/* Execute LINE as a shell command, returning its status. */
|
|
int
|
|
DEFUN(system, (line), register CONST char *line)
|
|
{
|
|
int status, save;
|
|
pid_t pid;
|
|
struct sigaction sa, intr, quit;
|
|
#ifndef WAITPID_CANNOT_BLOCK_SIGCHLD
|
|
sigset_t block, omask;
|
|
#endif
|
|
|
|
if (line == NULL)
|
|
return 1;
|
|
|
|
sa.sa_handler = SIG_IGN;
|
|
sa.sa_flags = 0;
|
|
__sigemptyset (&sa.sa_mask);
|
|
|
|
if (__sigaction (SIGINT, &sa, &intr) < 0)
|
|
return -1;
|
|
if (__sigaction (SIGQUIT, &sa, &quit) < 0)
|
|
{
|
|
save = errno;
|
|
(void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
|
|
errno = save;
|
|
return -1;
|
|
}
|
|
|
|
#ifndef WAITPID_CANNOT_BLOCK_SIGCHLD
|
|
|
|
/* SCO 3.2v4 has a bug where `waitpid' will never return if SIGCHLD is
|
|
blocked. This makes it impossible for `system' to be implemented in
|
|
compliance with POSIX.2-1992. They have acknowledged that this is a bug
|
|
but I have not seen nor heard of any forthcoming fix. */
|
|
|
|
__sigemptyset (&block);
|
|
__sigaddset (&block, SIGCHLD);
|
|
save = errno;
|
|
if (__sigprocmask (SIG_BLOCK, &block, &omask) < 0)
|
|
{
|
|
if (errno == ENOSYS)
|
|
errno = save;
|
|
else
|
|
{
|
|
save = errno;
|
|
(void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
|
|
(void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL);
|
|
errno = save;
|
|
return -1;
|
|
}
|
|
}
|
|
#define UNBLOCK __sigprocmask (SIG_SETMASK, &omask, (sigset_t *) NULL)
|
|
#else
|
|
#define UNBLOCK 0
|
|
#endif
|
|
|
|
pid = __vfork ();
|
|
if (pid == (pid_t) 0)
|
|
{
|
|
/* Child side. */
|
|
CONST char *new_argv[4];
|
|
new_argv[0] = SHELL_NAME;
|
|
new_argv[1] = "-c";
|
|
new_argv[2] = line;
|
|
new_argv[3] = NULL;
|
|
|
|
/* Restore the signals. */
|
|
(void) __sigaction (SIGINT, &intr, (struct sigaction *) NULL);
|
|
(void) __sigaction (SIGQUIT, &quit, (struct sigaction *) NULL);
|
|
(void) UNBLOCK;
|
|
|
|
/* Exec the shell. */
|
|
(void) __execve (SHELL_PATH, (char *CONST *) new_argv, __environ);
|
|
_exit (127);
|
|
}
|
|
else if (pid < (pid_t) 0)
|
|
/* The fork failed. */
|
|
status = -1;
|
|
else
|
|
/* Parent side. */
|
|
#ifdef NO_WAITPID
|
|
{
|
|
pid_t child;
|
|
do
|
|
{
|
|
child = __wait (&status);
|
|
if (child <= -1)
|
|
{
|
|
status = -1;
|
|
break;
|
|
}
|
|
} while (child != pid);
|
|
}
|
|
#else
|
|
if (__waitpid (pid, &status, 0) != pid)
|
|
status = -1;
|
|
#endif
|
|
|
|
save = errno;
|
|
if ((__sigaction (SIGINT, &intr, (struct sigaction *) NULL) |
|
|
__sigaction (SIGQUIT, &quit, (struct sigaction *) NULL) |
|
|
UNBLOCK) != 0)
|
|
{
|
|
if (errno == ENOSYS)
|
|
errno = save;
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
return status;
|
|
}
|