2 * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
3 * Copyright (c) 2003 Daniel Eischen <deischen@freebsd.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Neither the name of the author nor the names of any co-contributors
12 * may be used to endorse or promote products derived from this software
13 * without specific prior written permission.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SPDX-License-Identifier: BSD-3-Clause
31 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
32 * All rights reserved.
34 * Redistribution and use in source and binary forms, with or without
35 * modification, are permitted provided that the following conditions
37 * 1. Redistributions of source code must retain the above copyright
38 * notice, this list of conditions and the following disclaimer.
39 * 2. Redistributions in binary form must reproduce the above copyright
40 * notice, this list of conditions and the following disclaimer in the
41 * documentation and/or other materials provided with the distribution.
42 * 3. Neither the name of the author nor the names of any co-contributors
43 * may be used to endorse or promote products derived from this software
44 * without specific prior written permission.
46 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 #include <sys/cdefs.h>
61 __FBSDID("$FreeBSD$");
63 #include <sys/syscall.h>
64 #include "namespace.h"
72 #include "un-namespace.h"
74 #include "libc_private.h"
75 #include "rtld_lock.h"
76 #include "thr_private.h"
78 __weak_reference(_thr_atfork, _pthread_atfork);
79 __weak_reference(_thr_atfork, pthread_atfork);
82 _thr_atfork(void (*prepare)(void), void (*parent)(void),
85 struct pthread *curthread;
86 struct pthread_atfork *af;
90 if ((af = malloc(sizeof(struct pthread_atfork))) == NULL)
93 curthread = _get_curthread();
94 af->prepare = prepare;
97 THR_CRITICAL_ENTER(curthread);
98 _thr_rwl_wrlock(&_thr_atfork_lock);
99 TAILQ_INSERT_TAIL(&_thr_atfork_list, af, qe);
100 _thr_rwl_unlock(&_thr_atfork_lock);
101 THR_CRITICAL_LEAVE(curthread);
106 __pthread_cxa_finalize(struct dl_phdr_info *phdr_info)
108 atfork_head temp_list = TAILQ_HEAD_INITIALIZER(temp_list);
109 struct pthread *curthread;
110 struct pthread_atfork *af, *af1;
114 curthread = _get_curthread();
115 THR_CRITICAL_ENTER(curthread);
116 _thr_rwl_wrlock(&_thr_atfork_lock);
117 TAILQ_FOREACH_SAFE(af, &_thr_atfork_list, qe, af1) {
118 if (__elf_phdr_match_addr(phdr_info, af->prepare) ||
119 __elf_phdr_match_addr(phdr_info, af->parent) ||
120 __elf_phdr_match_addr(phdr_info, af->child)) {
121 TAILQ_REMOVE(&_thr_atfork_list, af, qe);
122 TAILQ_INSERT_TAIL(&temp_list, af, qe);
125 _thr_rwl_unlock(&_thr_atfork_lock);
126 THR_CRITICAL_LEAVE(curthread);
127 while ((af = TAILQ_FIRST(&temp_list)) != NULL) {
128 TAILQ_REMOVE(&temp_list, af, qe);
131 _thr_tsd_unload(phdr_info);
132 _thr_sigact_unload(phdr_info);
140 struct thr_fork_args {
141 enum thr_fork_mode mode;
147 thr_fork_impl(const struct thr_fork_args *a)
149 struct pthread *curthread;
150 struct pthread_atfork *af;
152 int errsave, cancelsave;
154 int rtld_locks[MAX_RTLD_LOCKS];
156 if (!_thr_is_inited()) {
159 return (__sys_fork());
161 return (__sys_pdfork(a->fdp, a->flags));
168 curthread = _get_curthread();
169 cancelsave = curthread->no_cancel;
170 curthread->no_cancel = 1;
171 _thr_rwl_rdlock(&_thr_atfork_lock);
173 /* Run down atfork prepare handlers. */
174 TAILQ_FOREACH_REVERSE(af, &_thr_atfork_list, atfork_head, qe) {
175 if (af->prepare != NULL)
180 * Block all signals until we reach a safe point.
182 _thr_signal_block(curthread);
183 _thr_signal_prefork();
186 * All bets are off as to what should happen soon if the parent
187 * process was not so kindly as to set up pthread fork hooks to
188 * relinquish all running threads.
190 if (_thr_isthreaded() != 0) {
192 __thr_malloc_prefork(curthread);
194 __thr_pshared_atfork_pre();
195 _rtld_atfork_pre(rtld_locks);
201 * Fork a new process.
202 * There is no easy way to pre-resolve the __sys_fork symbol
203 * without performing the fork. Use the syscall(2)
204 * indirection, the syscall symbol is resolved in
205 * _thr_rtld_init() with side-effect free call.
209 ret = syscall(SYS_fork);
212 ret = syscall(SYS_pdfork, a->fdp, a->flags);
223 curthread->cancel_pending = 0;
224 curthread->flags &= ~(THR_FLAGS_NEED_SUSPEND|THR_FLAGS_DETACHED);
227 * Thread list will be reinitialized, and later we call
228 * _libpthread_init(), it will add us back to list.
230 curthread->tlflags &= ~TLFLAGS_IN_TDLIST;
232 /* before thr_self() */
234 __thr_malloc_postfork(curthread);
236 /* child is a new kernel thread. */
237 thr_self(&curthread->tid);
239 /* clear other threads locked us. */
240 _thr_umutex_init(&curthread->lock);
241 _mutex_fork(curthread);
243 _thr_signal_postfork_child();
246 _rtld_atfork_post(rtld_locks);
247 __thr_pshared_atfork_post();
251 /* reinitalize library. */
252 _libpthread_init(curthread);
254 /* atfork is reinitialized by _libpthread_init()! */
255 _thr_rwl_rdlock(&_thr_atfork_lock);
263 /* Ready to continue, unblock signals. */
264 _thr_signal_unblock(curthread);
266 /* Run down atfork child handlers. */
267 TAILQ_FOREACH(af, &_thr_atfork_list, qe) {
268 if (af->child != NULL)
271 _thr_rwlock_unlock(&_thr_atfork_lock);
272 curthread->no_cancel = cancelsave;
277 _thr_signal_postfork();
280 __thr_malloc_postfork(curthread);
281 _rtld_atfork_post(rtld_locks);
282 __thr_pshared_atfork_post();
286 /* Ready to continue, unblock signals. */
287 _thr_signal_unblock(curthread);
289 /* Run down atfork parent handlers. */
290 TAILQ_FOREACH(af, &_thr_atfork_list, qe) {
291 if (af->parent != NULL)
295 _thr_rwlock_unlock(&_thr_atfork_lock);
296 curthread->no_cancel = cancelsave;
297 /* test async cancel */
298 if (curthread->cancel_async)
299 _thr_testcancel(curthread);
306 __weak_reference(__thr_fork, _fork);
311 struct thr_fork_args a;
314 return (thr_fork_impl(&a));
318 __thr_pdfork(int *fdp, int flags)
320 struct thr_fork_args a;
322 a.mode = MODE_PDFORK;
325 return (thr_fork_impl(&a));