xref: /netbsd-src/lib/libc/stdlib/system.c (revision 1394f01b4a9e99092957ca5d824d67219565d9b5)
1 /*	$NetBSD: system.c,v 1.12 1997/07/13 20:17:05 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1988 The Regents of the University of California.
5  * 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char *sccsid = "from: @(#)system.c	5.10 (Berkeley) 2/23/91";
40 #else
41 __RCSID("$NetBSD: system.c,v 1.12 1997/07/13 20:17:05 christos Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 #include <sys/types.h>
46 #include <sys/wait.h>
47 #include <signal.h>
48 #include <stdlib.h>
49 #include <unistd.h>
50 #include <paths.h>
51 
52 extern char **environ;
53 
54 int
55 system(command)
56 	const char *command;
57 {
58 	pid_t pid;
59 	sig_t intsave, quitsave;
60 	int omask;
61 	int pstat;
62 	char *argp[] = {"sh", "-c", (char *) command, NULL};
63 
64 	if (!command)		/* just checking... */
65 		return(1);
66 
67 	omask = sigblock(sigmask(SIGCHLD));
68 	switch(pid = vfork()) {
69 	case -1:			/* error */
70 		(void)sigsetmask(omask);
71 		return(-1);
72 	case 0:				/* child */
73 		(void)sigsetmask(omask);
74 		execve(_PATH_BSHELL, argp, environ);
75 		_exit(127);
76 	}
77 
78 	intsave = signal(SIGINT, SIG_IGN);
79 	quitsave = signal(SIGQUIT, SIG_IGN);
80 	pid = waitpid(pid, (int *)&pstat, 0);
81 	(void)sigsetmask(omask);
82 	(void)signal(SIGINT, intsave);
83 	(void)signal(SIGQUIT, quitsave);
84 	return(pid == -1 ? -1 : pstat);
85 }
86