libc/unistd/system.c

/*	$OpenBSD: system.c,v 1.8 2005/08/08 08:05:37 espie Exp $ */
/*
 * Copyright (c) 1988 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/types.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <paths.h>
#include <sys/wait.h>

extern char **environ;

int
system(const char *command)
{
  pid_t pid;
	sig_t intsave, quitsave;
	sigset_t mask, omask;
	int pstat;
	char *argp[] = {"sh", "-c", NULL, NULL};

	if (!command)		/* just checking... */
		return(1);

	argp[2] = (char *)command;

	sigemptyset(&mask);
	sigaddset(&mask, SIGCHLD);
	sigprocmask(SIG_BLOCK, &mask, &omask);
	switch (pid = vfork()) {
	case -1:			/* error */
		sigprocmask(SIG_SETMASK, &omask, NULL);
		return(-1);
	case 0:				/* child */
		sigprocmask(SIG_SETMASK, &omask, NULL);
		execve(_PATH_BSHELL, argp, environ);
    _exit(127);
  }

	intsave = (sig_t)  bsd_signal(SIGINT, SIG_IGN);
	quitsave = (sig_t) bsd_signal(SIGQUIT, SIG_IGN);
	pid = waitpid(pid, (int *)&pstat, 0);
	sigprocmask(SIG_SETMASK, &omask, NULL);
	(void)bsd_signal(SIGINT, intsave);
	(void)bsd_signal(SIGQUIT, quitsave);
	return (pid == -1 ? -1 : pstat);
}