1/*
2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)system.c 8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: head/lib/libc/stdlib/system.c 165903 2007-01-09 00:28:16Z imp $");
35
36#include "namespace.h"
37#include <sys/types.h>
38#include <sys/wait.h>
39#include <signal.h>
40#include <stdlib.h>
41#include <stddef.h>
42#include <unistd.h>
43#include <paths.h>
44#include <errno.h>
45#include "un-namespace.h"
46#include "libc_private.h"
47
48int
49__system(command)
50 const char *command;
51{
52 pid_t pid, savedpid;
53 int pstat;
54 struct sigaction ign, intact, quitact;
55 sigset_t newsigblock, oldsigblock;
56
57 if (!command) /* just checking... */
58 return(1);
59
60 /*
61 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save
62 * existing signal dispositions.
63 */
64 ign.sa_handler = SIG_IGN;
65 (void)sigemptyset(&ign.sa_mask);
66 ign.sa_flags = 0;
67 (void)_sigaction(SIGINT, &ign, &intact);
68 (void)_sigaction(SIGQUIT, &ign, &quitact);
69 (void)sigemptyset(&newsigblock);
70 (void)sigaddset(&newsigblock, SIGCHLD);
71 (void)_sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
72 switch(pid = fork()) {
73 case -1: /* error */
74 break;
75 case 0: /* child */
76 /*
77 * Restore original signal dispositions and exec the command.
78 */
79 (void)_sigaction(SIGINT, &intact, NULL);
80 (void)_sigaction(SIGQUIT, &quitact, NULL);
81 (void)_sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
82 execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
83 _exit(127);
84 default: /* parent */
85 savedpid = pid;
86 do {
87 pid = _wait4(savedpid, &pstat, 0, (struct rusage *)0);
88 } while (pid == -1 && errno == EINTR);
89 break;
90 }
91 (void)_sigaction(SIGINT, &intact, NULL);
92 (void)_sigaction(SIGQUIT, &quitact, NULL);
93 (void)_sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
94 return(pid == -1 ? -1 : pstat);
95}
96
97__weak_reference(__system, system);
98__weak_reference(__system, _system);