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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/lib/libc/stdlib/system.c,v 1.5.2.2 2001/10/10 12:50:22 alfred Exp $ 34 * $DragonFly: src/lib/libc/stdlib/system.c,v 1.5 2005/11/20 12:37:49 swildner Exp $ 35 * 36 * @(#)system.c 8.1 (Berkeley) 6/4/93 37 */ 38 39 #include "namespace.h" 40 #include <sys/types.h> 41 #include <sys/wait.h> 42 #include <signal.h> 43 #include <stdlib.h> 44 #include <stddef.h> 45 #include <unistd.h> 46 #include <paths.h> 47 #include <errno.h> 48 #include "un-namespace.h" 49 #include "libc_private.h" 50 51 int __system(const char *); 52 53 int 54 __system(const char *command) 55 { 56 pid_t pid, savedpid; 57 int pstat; 58 struct sigaction ign, intact, quitact; 59 sigset_t newsigblock, oldsigblock; 60 61 if (!command) /* just checking... */ 62 return(1); 63 64 /* 65 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save 66 * existing signal dispositions. 67 */ 68 ign.sa_handler = SIG_IGN; 69 sigemptyset(&ign.sa_mask); 70 ign.sa_flags = 0; 71 _sigaction(SIGINT, &ign, &intact); 72 _sigaction(SIGQUIT, &ign, &quitact); 73 sigemptyset(&newsigblock); 74 sigaddset(&newsigblock, SIGCHLD); 75 _sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock); 76 switch(pid = fork()) { 77 case -1: /* error */ 78 break; 79 case 0: /* child */ 80 /* 81 * Restore original signal dispositions and exec the command. 82 */ 83 _sigaction(SIGINT, &intact, NULL); 84 _sigaction(SIGQUIT, &quitact, NULL); 85 _sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 86 execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL); 87 _exit(127); 88 default: /* parent */ 89 savedpid = pid; 90 do { 91 pid = _wait4(savedpid, &pstat, 0, (struct rusage *)0); 92 } while (pid == -1 && errno == EINTR); 93 break; 94 } 95 _sigaction(SIGINT, &intact, NULL); 96 _sigaction(SIGQUIT, &quitact, NULL); 97 _sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 98 return(pid == -1 ? -1 : pstat); 99 } 100 101 __weak_reference(__system, system); 102 __weak_reference(__system, _system); 103