1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1988, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include "namespace.h"
33#include <sys/types.h>
34#include <sys/wait.h>
35#include <signal.h>
36#include <stdlib.h>
37#include <stddef.h>
38#include <string.h>
39#include <unistd.h>
40#include <paths.h>
41#include <errno.h>
42#include "un-namespace.h"
43#include "libc_private.h"
44
45#pragma weak system
46int
47system(const char *command)
48{
49
50	return (((int (*)(const char *))
51	    __libc_interposing[INTERPOS_system])(command));
52}
53
54int
55__libc_system(const char *command)
56{
57	pid_t pid, savedpid;
58	int pstat;
59	struct sigaction ign, intact, quitact;
60	sigset_t newsigblock, oldsigblock;
61
62	if (!command)		/* just checking... */
63		return(1);
64
65	(void)sigemptyset(&newsigblock);
66	(void)sigaddset(&newsigblock, SIGCHLD);
67	(void)sigaddset(&newsigblock, SIGINT);
68	(void)sigaddset(&newsigblock, SIGQUIT);
69	(void)__libc_sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
70	switch(pid = vfork()) {
71	/*
72	 * In the child, use unwrapped syscalls.  libthr is in
73	 * undefined state after vfork().
74	 */
75	case -1:			/* error */
76		(void)__libc_sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
77		return (-1);
78	case 0:				/* child */
79		/*
80		 * Restore original signal dispositions and exec the command.
81		 */
82		(void)__sys_sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
83		execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
84		_exit(127);
85	}
86	/*
87	 * If we are running means that the child has either completed
88	 * its execve, or has failed.
89	 * Block SIGINT/QUIT because sh -c handles it and wait for
90	 * it to clean up.
91	 */
92	memset(&ign, 0, sizeof(ign));
93	ign.sa_handler = SIG_IGN;
94	(void)sigemptyset(&ign.sa_mask);
95	(void)__libc_sigaction(SIGINT, &ign, &intact);
96	(void)__libc_sigaction(SIGQUIT, &ign, &quitact);
97	savedpid = pid;
98	do {
99		pid = _wait4(savedpid, &pstat, 0, (struct rusage *)0);
100	} while (pid == -1 && errno == EINTR);
101	(void)__libc_sigaction(SIGINT, &intact, NULL);
102	(void)__libc_sigaction(SIGQUIT,  &quitact, NULL);
103	(void)__libc_sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
104	return (pid == -1 ? -1 : pstat);
105}
106
107__weak_reference(__libc_system, __system);
108__weak_reference(__libc_system, _system);
109