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. 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 * @(#)system.c 8.1 (Berkeley) 6/4/93 30 * $FreeBSD: src/lib/libc/stdlib/system.c,v 1.11 2007/01/09 00:28:10 imp Exp $ 31 * $DragonFly: src/lib/libc/stdlib/system.c,v 1.5 2005/11/20 12:37:49 swildner Exp $ 32 */ 33 34 #include "namespace.h" 35 #include <sys/types.h> 36 #include <sys/wait.h> 37 #include <signal.h> 38 #include <stdlib.h> 39 #include <stddef.h> 40 #include <unistd.h> 41 #include <paths.h> 42 #include <errno.h> 43 #include "un-namespace.h" 44 #include "libc_private.h" 45 46 int 47 __system(const char *command) 48 { 49 pid_t pid, savedpid; 50 int pstat; 51 struct sigaction ign, intact, quitact; 52 sigset_t newsigblock, oldsigblock; 53 54 if (!command) /* just checking... */ 55 return(1); 56 57 /* 58 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save 59 * existing signal dispositions. 60 */ 61 ign.sa_handler = SIG_IGN; 62 sigemptyset(&ign.sa_mask); 63 ign.sa_flags = 0; 64 _sigaction(SIGINT, &ign, &intact); 65 _sigaction(SIGQUIT, &ign, &quitact); 66 sigemptyset(&newsigblock); 67 sigaddset(&newsigblock, SIGCHLD); 68 _sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock); 69 switch(pid = fork()) { 70 case -1: /* error */ 71 break; 72 case 0: /* child */ 73 /* 74 * Restore original signal dispositions and exec the command. 75 */ 76 _sigaction(SIGINT, &intact, NULL); 77 _sigaction(SIGQUIT, &quitact, NULL); 78 _sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 79 execl(_PATH_BSHELL, "sh", "-c", command, NULL); 80 _exit(127); 81 default: /* parent */ 82 savedpid = pid; 83 do { 84 pid = _wait4(savedpid, &pstat, 0, NULL); 85 } while (pid == -1 && errno == EINTR); 86 break; 87 } 88 _sigaction(SIGINT, &intact, NULL); 89 _sigaction(SIGQUIT, &quitact, NULL); 90 _sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 91 return(pid == -1 ? -1 : pstat); 92 } 93 94 __weak_reference(__system, system); 95 __weak_reference(__system, _system); 96