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: src/lib/libc/stdlib/system.c,v 1.11 2007/01/09 00:28:10 imp Exp $"); 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 <spawn.h> 44#include <paths.h> 45#include <errno.h> 46#include "un-namespace.h" 47#include "libc_private.h" 48 49#include <crt_externs.h> 50#define environ (*_NSGetEnviron()) 51 52#if __DARWIN_UNIX03 53#include <pthread.h> 54 55static pthread_mutex_t __systemfn_mutex = PTHREAD_MUTEX_INITIALIZER; 56extern int __unix_conforming; 57#endif /* __DARWIN_UNIX03 */ 58 59int 60__system(command) 61 const char *command; 62{ 63 pid_t pid, savedpid; 64 int pstat, err; 65 struct sigaction ign, intact, quitact; 66 sigset_t newsigblock, oldsigblock, defaultsig; 67 posix_spawnattr_t attr; 68 short flags = POSIX_SPAWN_SETSIGMASK; 69 const char *argv[] = {"sh", "-c", command, NULL}; 70 71#if __DARWIN_UNIX03 72 if (__unix_conforming == 0) 73 __unix_conforming = 1; 74#ifdef VARIANT_CANCELABLE 75 pthread_testcancel(); 76#endif /* VARIANT_CANCELABLE */ 77#endif /* __DARWIN_UNIX03 */ 78 79 if (!command) { /* just checking... */ 80 if (access(_PATH_BSHELL, F_OK) == -1) /* if no sh or no access */ 81 return(0); 82 else 83 return(1); 84 } 85 86 if ((err = posix_spawnattr_init(&attr)) != 0) { 87 errno = err; 88 return -1; 89 } 90 (void)sigemptyset(&defaultsig); 91 92#if __DARWIN_UNIX03 93 pthread_mutex_lock(&__systemfn_mutex); 94#endif /* __DARWIN_UNIX03 */ 95 /* 96 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save 97 * existing signal dispositions. 98 */ 99 ign.sa_handler = SIG_IGN; 100 (void)sigemptyset(&ign.sa_mask); 101 ign.sa_flags = 0; 102 (void)_sigaction(SIGINT, &ign, &intact); 103 if (intact.sa_handler != SIG_IGN) { 104 sigaddset(&defaultsig, SIGINT); 105 flags |= POSIX_SPAWN_SETSIGDEF; 106 } 107 (void)_sigaction(SIGQUIT, &ign, &quitact); 108 if (quitact.sa_handler != SIG_IGN) { 109 sigaddset(&defaultsig, SIGQUIT); 110 flags |= POSIX_SPAWN_SETSIGDEF; 111 } 112 (void)sigemptyset(&newsigblock); 113 (void)sigaddset(&newsigblock, SIGCHLD); 114 (void)_sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock); 115 (void)posix_spawnattr_setsigmask(&attr, &oldsigblock); 116 if (flags & POSIX_SPAWN_SETSIGDEF) { 117 (void)posix_spawnattr_setsigdefault(&attr, &defaultsig); 118 } 119 (void)posix_spawnattr_setflags(&attr, flags); 120 121 err = posix_spawn(&pid, _PATH_BSHELL, NULL, &attr, (char *const *)argv, environ); 122 (void)posix_spawnattr_destroy(&attr); 123 if (err == 0) { 124 savedpid = pid; 125 do { 126 pid = _wait4(savedpid, &pstat, 0, (struct rusage *)0); 127 } while (pid == -1 && errno == EINTR); 128 if (pid == -1) pstat = -1; 129 } else if (err == ENOMEM || err == EAGAIN) { /* as if fork failed */ 130 pstat = -1; 131 } else { 132 pstat = W_EXITCODE(127, 0); /* couldn't exec shell */ 133 } 134 135 (void)_sigaction(SIGINT, &intact, NULL); 136 (void)_sigaction(SIGQUIT, &quitact, NULL); 137 (void)_sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 138#if __DARWIN_UNIX03 139 pthread_mutex_unlock(&__systemfn_mutex); 140#endif /* __DARWIN_UNIX03 */ 141 return(pstat); 142} 143 144__weak_reference(__system, system); 145__weak_reference(__system, _system); 146