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/* $OpenBSD: uthread_exit.c,v 1.11 1999/11/30 04:53:24 d Exp $ */
/*
* 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 AUTHOR 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.
*
* $FreeBSD: uthread_exit.c,v 1.12 1999/08/30 15:45:42 dt Exp $
*/
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
void _exit(int status)
{
int flags;
int i;
struct itimerval itimer;
/* Disable the interval timer: */
itimer.it_interval.tv_sec = 0;
itimer.it_interval.tv_usec = 0;
itimer.it_value.tv_sec = 0;
itimer.it_value.tv_usec = 0;
setitimer(_ITIMER_SCHED_TIMER, &itimer, NULL);
/* Close the pthread kernel pipe: */
_thread_sys_close(_thread_kern_pipe[0]);
_thread_sys_close(_thread_kern_pipe[1]);
/*
* Enter a loop to set all file descriptors to blocking
* if they were not created as non-blocking:
*/
for (i = 0; i < _thread_dtablesize; i++) {
/* Check if this file descriptor is in use: */
if (_thread_fd_table[i] != NULL &&
!(_thread_fd_table[i]->flags & O_NONBLOCK)) {
/* Get the current flags: */
flags = _thread_sys_fcntl(i, F_GETFL, NULL);
/* Clear the nonblocking file descriptor flag: */
_thread_sys_fcntl(i, F_SETFL, flags & ~O_NONBLOCK);
}
}
/* Call the _exit syscall: */
_thread_sys__exit(status);
}
static void
numlcat(char *s, int l, size_t sz)
{
char digit[2];
/* Inefficient. */
if (l < 0) {
l = -l;
strlcat(s, "-", sz);
}
if (l >= 10)
numlcat(s, l / 10, sz);
digit[0] = "0123456789"[l % 10];
digit[1] = '\0';
strlcat(s, digit, sz);
}
void
_thread_exit(const char *fname, int lineno, const char *string)
{
char s[256];
/* Prepare an error message string: */
strlcpy(s, "Fatal error '", sizeof s);
strlcat(s, string, sizeof s);
strlcat(s, "' at line ", sizeof s);
numlcat(s, lineno, sizeof s);
strlcat(s, " in file ", sizeof s);
strlcat(s, fname, sizeof s);
strlcat(s, " (errno = ", sizeof s);
numlcat(s, errno, sizeof s);
strlcat(s, ")\n", sizeof s);
/* Write the string to the standard error file descriptor: */
_thread_sys_write(2, s, strlen(s));
/* Force this process to exit: */
/* XXX - Do we want abort to be conditional on _PTHREADS_INVARIANTS? */
#if defined(_PTHREADS_INVARIANTS)
abort();
#else
_exit(1);
#endif
}
void
pthread_exit(void *status)
{
int sig;
long l;
pthread_t pthread;
/* Check if this thread is already in the process of exiting: */
if ((_thread_run->flags & PTHREAD_EXITING) != 0) {
PANIC("Thread has called pthread_exit() from a destructor. POSIX 1003.1 1996 s16.2.5.2 does not allow this!");
}
/* Flag this thread as exiting: */
_thread_run->flags |= PTHREAD_EXITING;
/* Save the return value: */
_thread_run->ret = status;
while (_thread_run->cleanup != NULL) {
pthread_cleanup_pop(1);
}
if (_thread_run->attr.cleanup_attr != NULL) {
_thread_run->attr.cleanup_attr(_thread_run->attr.arg_attr);
}
/* Check if there is thread specific data: */
if (_thread_run->specific_data != NULL) {
/* Run the thread-specific data destructors: */
_thread_cleanupspecific();
}
/*
* Defer signals to protect the scheduling queues from access
* by the signal handler:
*/
_thread_kern_sig_defer();
/* Check if there are any threads joined to this one: */
while ((pthread = TAILQ_FIRST(&(_thread_run->join_queue))) != NULL) {
/* Remove the thread from the queue: */
TAILQ_REMOVE(&_thread_run->join_queue, pthread, qe);
/* Wake the joined thread and let it detach this thread: */
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
}
/*
* Undefer and handle pending signals, yielding if necessary:
*/
_thread_kern_sig_undefer();
/*
* Lock the garbage collector mutex to ensure that the garbage
* collector is not using the dead thread list.
*/
if (pthread_mutex_lock(&_gc_mutex) != 0)
PANIC("Cannot lock gc mutex");
/* Add this thread to the list of dead threads. */
TAILQ_INSERT_HEAD(&_dead_list, _thread_run, dle);
/*
* Defer signals to protect the scheduling queues from access
* by the signal handler:
*/
_thread_kern_sig_defer();
/* Remove this thread from the thread list: */
TAILQ_REMOVE(&_thread_list, _thread_run, tle);
/*
* Undefer and handle pending signals, yielding if necessary:
*/
_thread_kern_sig_undefer();
/*
* Signal the garbage collector thread that there is something
* to clean up.
*/
if (pthread_cond_signal(&_gc_cond) != 0)
PANIC("Cannot signal gc cond");
/*
* Mark the thread as dead so it will not return if it
* gets context switched out when the mutex is unlocked.
*/
PTHREAD_SET_STATE(_thread_run, PS_DEAD);
/* Unlock the garbage collector mutex: */
if (pthread_mutex_unlock(&_gc_mutex) != 0)
PANIC("Cannot lock gc mutex");
/* This this thread will never be re-scheduled. */
_thread_kern_sched(NULL);
/* This point should not be reached. */
PANIC("Dead thread has resumed");
}
#endif
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