/* $NetBSD: system.c,v 1.24 2012/06/25 22:32:45 abs Exp $ */ /* * Copyright (c) 1988, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char sccsid[] = "@(#)system.c 8.1 (Berkeley) 6/4/93"; #else __RCSID("$NetBSD: system.c,v 1.24 2012/06/25 22:32:45 abs Exp $"); #endif #endif /* LIBC_SCCS and not lint */ #include "namespace.h" #include #include #include #include #include #include #include #include "env.h" #include "reentrant.h" int system(const char *command) { pid_t pid; struct sigaction intsa, quitsa, sa; sigset_t nmask, omask; int pstat; const char *argp[] = {"sh", "-c", NULL, NULL}; argp[2] = command; /* * ISO/IEC 9899:1999 in 7.20.4.6 describes this special case. * We need to check availability of a command interpreter. */ if (command == NULL) { if (access(_PATH_BSHELL, X_OK) == 0) return 1; return 0; } sa.sa_handler = SIG_IGN; sigemptyset(&sa.sa_mask); sa.sa_flags = 0; if (sigaction(SIGINT, &sa, &intsa) == -1) return -1; if (sigaction(SIGQUIT, &sa, &quitsa) == -1) { sigaction(SIGINT, &intsa, NULL); return -1; } sigemptyset(&nmask); sigaddset(&nmask, SIGCHLD); if (sigprocmask(SIG_BLOCK, &nmask, &omask) == -1) { sigaction(SIGINT, &intsa, NULL); sigaction(SIGQUIT, &quitsa, NULL); return -1; } (void)__readlockenv(); switch(pid = vfork()) { case -1: /* error */ (void)__unlockenv(); sigaction(SIGINT, &intsa, NULL); sigaction(SIGQUIT, &quitsa, NULL); (void)sigprocmask(SIG_SETMASK, &omask, NULL); return -1; case 0: /* child */ sigaction(SIGINT, &intsa, NULL); sigaction(SIGQUIT, &quitsa, NULL); (void)sigprocmask(SIG_SETMASK, &omask, NULL); execve(_PATH_BSHELL, __UNCONST(argp), environ); _exit(127); } (void)__unlockenv(); while (waitpid(pid, &pstat, 0) == -1) { if (errno != EINTR) { pstat = -1; break; } } sigaction(SIGINT, &intsa, NULL); sigaction(SIGQUIT, &quitsa, NULL); (void)sigprocmask(SIG_SETMASK, &omask, NULL); return (pstat); }