system.c revision 84417
150764Smarkm/* 250764Smarkm * Copyright (c) 1988, 1993 350764Smarkm * The Regents of the University of California. All rights reserved. 450764Smarkm * 550764Smarkm * Redistribution and use in source and binary forms, with or without 650764Smarkm * modification, are permitted provided that the following conditions 750764Smarkm * are met: 850764Smarkm * 1. Redistributions of source code must retain the above copyright 950764Smarkm * notice, this list of conditions and the following disclaimer. 1050764Smarkm * 2. Redistributions in binary form must reproduce the above copyright 1150764Smarkm * notice, this list of conditions and the following disclaimer in the 1250764Smarkm * documentation and/or other materials provided with the distribution. 1350764Smarkm * 3. All advertising materials mentioning features or use of this software 1450764Smarkm * must display the following acknowledgement: 1550764Smarkm * This product includes software developed by the University of 1650764Smarkm * California, Berkeley and its contributors. 1750764Smarkm * 4. Neither the name of the University nor the names of its contributors 1850764Smarkm * may be used to endorse or promote products derived from this software 1950764Smarkm * without specific prior written permission. 2050764Smarkm * 2150764Smarkm * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2250764Smarkm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2350764Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2450764Smarkm * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2550764Smarkm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2650764Smarkm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2750764Smarkm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2850764Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2950764Smarkm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3050764Smarkm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3150764Smarkm * SUCH DAMAGE. 3250764Smarkm * 3350764Smarkm * $FreeBSD: head/lib/libc/stdlib/system.c 84417 2001-10-03 11:01:39Z alfred $ 3450764Smarkm */ 3550764Smarkm 3650764Smarkm#if defined(LIBC_SCCS) && !defined(lint) 3750764Smarkmstatic char sccsid[] = "@(#)system.c 8.1 (Berkeley) 6/4/93"; 3850764Smarkm#endif /* LIBC_SCCS and not lint */ 3950764Smarkm 4050764Smarkm#include "namespace.h" 4150764Smarkm#include <sys/types.h> 4250764Smarkm#include <sys/wait.h> 4350764Smarkm#include <signal.h> 4450764Smarkm#include <stdlib.h> 4550764Smarkm#include <stddef.h> 4650764Smarkm#include <unistd.h> 4750764Smarkm#include <paths.h> 4850764Smarkm#include <errno.h> 4950764Smarkm#include "un-namespace.h" 5050764Smarkm#include "libc_private.h" 5150764Smarkm 5250764Smarkmint 5350764Smarkm__system(command) 5450764Smarkm const char *command; 5550764Smarkm{ 5650764Smarkm pid_t pid, savedpid; 5750764Smarkm int pstat; 5850764Smarkm struct sigaction ign, intact, quitact; 5950764Smarkm sigset_t newsigblock, oldsigblock; 6050764Smarkm 6150764Smarkm if (!command) /* just checking... */ 6250764Smarkm return(1); 6350764Smarkm 6450764Smarkm /* 6550764Smarkm * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save 6650764Smarkm * existing signal dispositions. 6750764Smarkm */ 6850764Smarkm ign.sa_handler = SIG_IGN; 6950764Smarkm (void)sigemptyset(&ign.sa_mask); 7050764Smarkm ign.sa_flags = 0; 7150764Smarkm (void)_sigaction(SIGINT, &ign, &intact); 7250764Smarkm (void)_sigaction(SIGQUIT, &ign, &quitact); 7350764Smarkm (void)sigemptyset(&newsigblock); 74 (void)sigaddset(&newsigblock, SIGCHLD); 75 (void)_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 (void)_sigaction(SIGINT, &intact, NULL); 84 (void)_sigaction(SIGQUIT, &quitact, NULL); 85 (void)_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 (void)_sigaction(SIGINT, &intact, NULL); 96 (void)_sigaction(SIGQUIT, &quitact, NULL); 97 (void)_sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 98 return(pid == -1 ? -1 : pstat); 99} 100 101__weak_reference(__system, system); 102__weak_reference(__system, _system); 103