1/* 2 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au> 3 * 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 author nor the names of any co-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 JOHN BIRRELL 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 AUTHOR 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 * $FreeBSD$ 30 */ 31 32#include "namespace.h" 33#include <errno.h> 34#include <string.h> 35#include <stdlib.h> 36#include <unistd.h> 37#include <fcntl.h> 38#include <pthread.h> 39#include <spinlock.h> 40#include <sys/signalvar.h> 41#include "un-namespace.h" 42 43#include "libc_private.h" 44#include "thr_private.h" 45 46pid_t _fork(void); 47 48__weak_reference(_fork, fork); 49 50pid_t 51_fork(void) 52{ 53 sigset_t sigset, oldset; 54 struct pthread *curthread; 55 struct pthread_atfork *af; 56 pid_t ret; 57 int errsave; 58 59 curthread = _get_curthread(); 60 61 if (!_kse_isthreaded()) { 62 SIGFILLSET(sigset); 63 __sys_sigprocmask(SIG_SETMASK, &sigset, &oldset); 64 ret = __sys_fork(); 65 if (ret == 0) 66 /* Child */ 67 __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, 68 NULL); 69 else 70 __sys_sigprocmask(SIG_SETMASK, &oldset, NULL); 71 return (ret); 72 } 73 74 /* 75 * Masks all signals until we reach a safe point in 76 * _kse_single_thread, and the signal masks will be 77 * restored in that function, for M:N thread, all 78 * signals were already masked in kernel atomically, 79 * we only need to do this for bound thread. 80 */ 81 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) { 82 SIGFILLSET(sigset); 83 __sys_sigprocmask(SIG_SETMASK, &sigset, &oldset); 84 } 85 86 _pthread_mutex_lock(&_thr_atfork_mutex); 87 88 /* Run down atfork prepare handlers. */ 89 TAILQ_FOREACH_REVERSE(af, &_thr_atfork_list, atfork_head, qe) { 90 if (af->prepare != NULL) 91 af->prepare(); 92 } 93 94 /* Fork a new process: */ 95 if (_kse_isthreaded() != 0) { 96 _malloc_prefork(); 97 } 98 if ((ret = __sys_fork()) == 0) { 99 /* Child process */ 100 errsave = errno; 101 102 /* Kernel signal mask is restored in _kse_single_thread */ 103 _kse_single_thread(curthread); 104 105 /* Run down atfork child handlers. */ 106 TAILQ_FOREACH(af, &_thr_atfork_list, qe) { 107 if (af->child != NULL) 108 af->child(); 109 } 110 _thr_mutex_reinit(&_thr_atfork_mutex); 111 } else { 112 if (_kse_isthreaded() != 0) { 113 _malloc_postfork(); 114 } 115 errsave = errno; 116 if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) { 117 __sys_sigprocmask(SIG_SETMASK, &oldset, NULL); 118 } 119 /* Run down atfork parent handlers. */ 120 TAILQ_FOREACH(af, &_thr_atfork_list, qe) { 121 if (af->parent != NULL) 122 af->parent(); 123 } 124 _pthread_mutex_unlock(&_thr_atfork_mutex); 125 } 126 errno = errsave; 127 128 /* Return the process ID: */ 129 return (ret); 130} 131