system.c revision 287292
159769Sgrog/* 259769Sgrog * Copyright (c) 1988, 1993 324424Swosch * The Regents of the University of California. All rights reserved. 424424Swosch * 524424Swosch * Redistribution and use in source and binary forms, with or without 624424Swosch * modification, are permitted provided that the following conditions 724424Swosch * are met: 824424Swosch * 1. Redistributions of source code must retain the above copyright 924424Swosch * notice, this list of conditions and the following disclaimer. 1024424Swosch * 2. Redistributions in binary form must reproduce the above copyright 1124424Swosch * notice, this list of conditions and the following disclaimer in the 1224424Swosch * documentation and/or other materials provided with the distribution. 1324424Swosch * 3. Neither the name of the University nor the names of its contributors 1424424Swosch * may be used to endorse or promote products derived from this software 1542704Swosch * without specific prior written permission. 1642704Swosch * 1742704Swosch * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 1824424Swosch * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1942704Swosch * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2042704Swosch * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2142704Swosch * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2242704Swosch * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2342704Swosch * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2442704Swosch * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2542704Swosch * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2642704Swosch * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2742704Swosch * SUCH DAMAGE. 2842704Swosch */ 2942704Swosch 3059769Sgrog#if defined(LIBC_SCCS) && !defined(lint) 3159769Sgrogstatic char sccsid[] = "@(#)system.c 8.1 (Berkeley) 6/4/93"; 3259769Sgrog#endif /* LIBC_SCCS and not lint */ 3359769Sgrog#include <sys/cdefs.h> 3459769Sgrog__FBSDID("$FreeBSD: head/lib/libc/stdlib/system.c 287292 2015-08-29 14:25:01Z kib $"); 3559769Sgrog 3659769Sgrog#include "namespace.h" 3759769Sgrog#include <sys/types.h> 3859769Sgrog#include <sys/wait.h> 3924424Swosch#include <signal.h> 4042704Swosch#include <stdlib.h> 4124424Swosch#include <stddef.h> 4242704Swosch#include <string.h> 4324424Swosch#include <unistd.h> 4442704Swosch#include <paths.h> 4524424Swosch#include <errno.h> 4624424Swosch#include "un-namespace.h" 4724424Swosch#include "libc_private.h" 4842704Swosch 4925031Swosch#pragma weak system 5059156Swoschint 5125031Swoschsystem(const char *command) 5225031Swosch{ 5324424Swosch 5424424Swosch return (((int (*)(const char *)) 5524424Swosch __libc_interposing[INTERPOS_system])(command)); 5624424Swosch} 5771231Sitojun 5824424Swoschint 5971231Sitojun__libc_system(const char *command) 6025031Swosch{ 6171231Sitojun pid_t pid, savedpid; 6224424Swosch int pstat; 6325031Swosch struct sigaction ign, intact, quitact; 6425031Swosch sigset_t newsigblock, oldsigblock; 6571231Sitojun 6625031Swosch if (!command) /* just checking... */ 6771231Sitojun return(1); 6870110Swosch 6970110Swosch (void)sigemptyset(&newsigblock); 7070110Swosch (void)sigaddset(&newsigblock, SIGCHLD); 7170110Swosch (void)sigaddset(&newsigblock, SIGINT); 7270110Swosch (void)sigaddset(&newsigblock, SIGQUIT); 7370110Swosch (void)__libc_sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock); 7470110Swosch switch(pid = vfork()) { 7570110Swosch /* 7670110Swosch * In the child, use unwrapped syscalls. libthr is in 7770110Swosch * undefined state after vfork(). 7870110Swosch */ 7980675Sasmodai case -1: /* error */ 8080675Sasmodai (void)__libc_sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 8180675Sasmodai return (-1); 8280675Sasmodai case 0: /* child */ 8380675Sasmodai /* 8480675Sasmodai * Restore original signal dispositions and exec the command. 8580675Sasmodai */ 8680675Sasmodai (void)__sys_sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 8780675Sasmodai execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL); 8880675Sasmodai _exit(127); 8980675Sasmodai } 9080675Sasmodai /* 9180675Sasmodai * If we are running means that the child has either completed 9280675Sasmodai * its execve, or has failed. 9380675Sasmodai * Block SIGINT/QUIT because sh -c handles it and wait for 9480675Sasmodai * it to clean up. 9580675Sasmodai */ 9680675Sasmodai memset(&ign, 0, sizeof(ign)); 9780675Sasmodai ign.sa_handler = SIG_IGN; 9880675Sasmodai (void)sigemptyset(&ign.sa_mask); 9980675Sasmodai (void)__libc_sigaction(SIGINT, &ign, &intact); 10080675Sasmodai (void)__libc_sigaction(SIGQUIT, &ign, &quitact); 10180675Sasmodai savedpid = pid; 10280675Sasmodai do { 10380675Sasmodai pid = _wait4(savedpid, &pstat, 0, (struct rusage *)0); 10480675Sasmodai } while (pid == -1 && errno == EINTR); 10580675Sasmodai (void)__libc_sigaction(SIGINT, &intact, NULL); 10680675Sasmodai (void)__libc_sigaction(SIGQUIT, &quitact, NULL); 10780675Sasmodai (void)__libc_sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 10880675Sasmodai return (pid == -1 ? -1 : pstat); 10980675Sasmodai} 11080675Sasmodai 11180675Sasmodai__weak_reference(__libc_system, __system); 11280675Sasmodai__weak_reference(__libc_system, _system); 11380675Sasmodai