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diff --git a/lib/libpthread/thread/thr_fork.c b/lib/libpthread/thread/thr_fork.c
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+/*
+ * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by John Birrell.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+pid_t
+fork(void)
+{
+ int flags;
+ pid_t ret;
+ pthread_t pthread;
+ pthread_t pthread_next;
+
+ /* Lock the thread list: */
+ _lock_thread_list();
+
+ /* Fork a new process: */
+ if ((ret = _thread_sys_fork()) != 0) {
+ /* Parent process or error. Nothing to do here. */
+ } else {
+ /* Close the pthread kernel pipe: */
+ _thread_sys_close(_thread_kern_pipe[0]);
+ _thread_sys_close(_thread_kern_pipe[1]);
+
+ /* Reset signals pending for the running thread: */
+ _thread_run->sigpend = 0;
+
+ /*
+ * Create a pipe that is written to by the signal handler to
+ * prevent signals being missed in calls to
+ * _thread_sys_select:
+ */
+ if (_thread_sys_pipe(_thread_kern_pipe) != 0) {
+ /* Cannot create pipe, so abort: */
+ PANIC("Cannot create pthread kernel pipe for forked process");
+ }
+ /* Get the flags for the read pipe: */
+ else if ((flags = _thread_sys_fcntl(_thread_kern_pipe[0], F_GETFL, NULL)) == -1) {
+ /* Abort this application: */
+ abort();
+ }
+ /* Make the read pipe non-blocking: */
+ else if (_thread_sys_fcntl(_thread_kern_pipe[0], F_SETFL, flags | O_NONBLOCK) == -1) {
+ /* Abort this application: */
+ abort();
+ }
+ /* Get the flags for the write pipe: */
+ else if ((flags = _thread_sys_fcntl(_thread_kern_pipe[1], F_GETFL, NULL)) == -1) {
+ /* Abort this application: */
+ abort();
+ }
+ /* Make the write pipe non-blocking: */
+ else if (_thread_sys_fcntl(_thread_kern_pipe[1], F_SETFL, flags | O_NONBLOCK) == -1) {
+ /* Abort this application: */
+ abort();
+ } else {
+ /* Point to the first thread in the list: */
+ pthread = _thread_link_list;
+
+ /*
+ * Enter a loop to remove all threads other than
+ * the running thread from the thread list:
+ */
+ while (pthread != NULL) {
+ pthread_next = pthread->nxt;
+ if (pthread == _thread_run) {
+ _thread_link_list = pthread;
+ pthread->nxt = NULL;
+ } else {
+ if (pthread->attr.stackaddr_attr ==
+ NULL && pthread->stack != NULL)
+ /*
+ * Free the stack of the
+ * dead thread:
+ */
+ free(pthread->stack);
+
+ if (pthread->specific_data != NULL)
+ free(pthread->specific_data);
+
+ free(pthread);
+ }
+
+ /* Point to the next thread: */
+ pthread = pthread_next;
+ }
+ }
+ }
+
+ /* Unock the thread list: */
+ _unlock_thread_list();
+
+ /* Return the process ID: */
+ return (ret);
+}
+#endif
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