0a3fa43c7e
signal handler. Explicitly check for jumps to anywhere other than the current stack, since such jumps are undefined according to POSIX. While we're at it, convert thread cancellation to use continuations, since it's cleaner than the original cancellation code. Avoid delivering a signal to a thread twice. This was a pre-existing bug, but was likely unexposed until these other changes were made. Defer signals generated by pthread_kill() so that they can be delivered on the appropriate stack. deischen claims that this is unnecessary, which is likely true, but without this change, pthread_kill() can cause undefined priority queue states and/or PANICs in [sig|_]longjmp(), so I'm leaving this in for now. To compile this code out and exercise the bug, define the _NO_UNDISPATCH cpp macro. Defining _PTHREADS_INVARIANTS as well will cause earlier crashes. PR: kern/14685 Collaboration with: deischen
777 lines
21 KiB
C
777 lines
21 KiB
C
/*
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* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by John Birrell.
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* 4. Neither the name of the author nor the names of any co-contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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#include <sys/param.h>
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#include <sys/types.h>
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#include <sys/signalvar.h>
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#include <signal.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <setjmp.h>
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#include <errno.h>
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#ifdef _THREAD_SAFE
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#include <pthread.h>
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#include "pthread_private.h"
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/* Prototypes: */
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static void thread_sig_check_state(pthread_t pthread, int sig);
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static void thread_sig_finish_longjmp(void *arg);
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static void handle_state_change(pthread_t pthread);
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/* Static variables: */
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static spinlock_t signal_lock = _SPINLOCK_INITIALIZER;
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static unsigned int pending_sigs[NSIG];
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static unsigned int handled_sigs[NSIG];
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static int volatile check_pending = 0;
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static int volatile check_waiting = 0;
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/* Initialize signal handling facility: */
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void
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_thread_sig_init(void)
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{
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int i;
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/* Clear pending and handled signal counts: */
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for (i = 1; i < NSIG; i++) {
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pending_sigs[i - 1] = 0;
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handled_sigs[i - 1] = 0;
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}
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/* Clear the lock: */
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signal_lock.access_lock = 0;
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/* Clear the process pending signals: */
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sigemptyset(&_process_sigpending);
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}
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void
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_thread_sig_handler(int sig, int code, ucontext_t * scp)
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{
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pthread_t pthread, pthread_next;
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int i;
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char c;
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/* Check if an interval timer signal: */
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if (sig == _SCHED_SIGNAL) {
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if (_thread_kern_in_sched != 0) {
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/*
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* The scheduler is already running; ignore this
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* signal.
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*/
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}
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/*
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* Check if the scheduler interrupt has come when
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* the currently running thread has deferred thread
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* signals.
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*/
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else if (_thread_run->sig_defer_count > 0)
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_thread_run->yield_on_sig_undefer = 1;
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else {
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/*
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* Schedule the next thread. This function is not
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* expected to return because it will do a longjmp
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* instead.
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*/
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_thread_kern_sched(scp);
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/*
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* This point should not be reached, so abort the
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* process:
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*/
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PANIC("Returned to signal function from scheduler");
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}
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}
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/*
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* Check if the kernel has been interrupted while the scheduler
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* is accessing the scheduling queues or if there is a currently
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* running thread that has deferred signals.
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*/
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else if ((_queue_signals != 0) || ((_thread_kern_in_sched == 0) &&
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(_thread_run->sig_defer_count > 0))) {
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/* Cast the signal number to a character variable: */
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c = sig;
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/*
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* Write the signal number to the kernel pipe so that it will
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* be ready to read when this signal handler returns.
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*/
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_thread_sys_write(_thread_kern_pipe[1], &c, 1);
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/* Indicate that there are queued signals in the pipe. */
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_sigq_check_reqd = 1;
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} else {
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if (_atomic_lock(&signal_lock.access_lock)) {
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/* There is another signal handler running: */
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pending_sigs[sig - 1]++;
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check_pending = 1;
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}
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else {
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/* It's safe to handle the signal now. */
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pthread = _thread_sig_handle(sig, scp);
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/* Reset the pending and handled count back to 0: */
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pending_sigs[sig - 1] = 0;
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handled_sigs[sig - 1] = 0;
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if (pthread == NULL)
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signal_lock.access_lock = 0;
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else {
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sigaddset(&pthread->sigmask, sig);
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/*
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* Make sure not to deliver the same signal to
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* the thread twice. sigpend is potentially
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* modified by the call chain
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* _thread_sig_handle() -->
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* thread_sig_check_state(), which can happen
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* just above.
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*/
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if (sigismember(&pthread->sigpend, sig))
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sigdelset(&pthread->sigpend, sig);
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signal_lock.access_lock = 0;
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_thread_sig_deliver(pthread, sig);
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sigdelset(&pthread->sigmask, sig);
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}
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}
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/* Enter a loop to process pending signals: */
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while ((check_pending != 0) &&
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(_atomic_lock(&signal_lock.access_lock) == 0)) {
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check_pending = 0;
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for (i = 1; i < NSIG; i++) {
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if (pending_sigs[i - 1] > handled_sigs[i - 1]) {
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pending_sigs[i - 1] = handled_sigs[i - 1];
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pthread = _thread_sig_handle(i, scp);
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if (pthread != NULL) {
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sigaddset(&pthread->sigmask, i);
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/* Save the old state: */
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pthread->oldstate = pthread->state;
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signal_lock.access_lock = 0;
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_thread_sig_deliver(pthread, i);
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sigdelset(&pthread->sigmask, i);
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if (_atomic_lock(&signal_lock.access_lock)) {
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check_pending = 1;
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/*
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* Have the lock holder take care
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* of any state changes:
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*/
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if (pthread->state != pthread->oldstate)
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check_waiting = 1;
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return;
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}
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if (pthread->state != pthread->oldstate)
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handle_state_change(pthread);
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}
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}
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}
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while (check_waiting != 0) {
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check_waiting = 0;
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/*
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* Enter a loop to wake up all threads waiting
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* for a process to complete:
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*/
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for (pthread = TAILQ_FIRST(&_waitingq);
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pthread != NULL; pthread = pthread_next) {
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pthread_next = TAILQ_NEXT(pthread, pqe);
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if (pthread->state == PS_RUNNING)
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handle_state_change(pthread);
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}
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}
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/* Release the lock: */
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signal_lock.access_lock = 0;
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}
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/*
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* Check to see if the current thread performed a
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* [sig|_]longjmp() out of a signal handler.
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*/
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if ((_thread_run->jmpflags & (JMPFLAGS_LONGJMP |
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JMPFLAGS__LONGJMP)) != 0) {
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_thread_run->jmpflags = JMPFLAGS_NONE;
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__longjmp(_thread_run->nested_jmp.jmp,
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_thread_run->longjmp_val);
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} else if ((_thread_run->jmpflags & JMPFLAGS_SIGLONGJMP) != 0) {
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_thread_run->jmpflags = JMPFLAGS_NONE;
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__siglongjmp(_thread_run->nested_jmp.sigjmp,
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_thread_run->longjmp_val);
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}
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}
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}
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pthread_t
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_thread_sig_handle(int sig, ucontext_t * scp)
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{
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int i, handler_installed;
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pthread_t pthread, pthread_next;
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pthread_t suspended_thread, signaled_thread;
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/* Check if the signal requires a dump of thread information: */
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if (sig == SIGINFO)
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/* Dump thread information to file: */
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_thread_dump_info();
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/* Check if an interval timer signal: */
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else if (sig == _SCHED_SIGNAL) {
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/*
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* This shouldn't ever occur (should this panic?).
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*/
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} else {
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/* Check if a child has terminated: */
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if (sig == SIGCHLD) {
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/*
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* Go through the file list and set all files
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* to non-blocking again in case the child
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* set some of them to block. Sigh.
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*/
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for (i = 0; i < _thread_dtablesize; i++) {
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/* Check if this file is used: */
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if (_thread_fd_table[i] != NULL) {
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/*
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* Set the file descriptor to
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* non-blocking:
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*/
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_thread_sys_fcntl(i, F_SETFL,
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_thread_fd_table[i]->flags |
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O_NONBLOCK);
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}
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}
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/*
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* Enter a loop to wake up all threads waiting
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* for a process to complete:
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*/
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for (pthread = TAILQ_FIRST(&_waitingq);
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pthread != NULL; pthread = pthread_next) {
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/*
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* Grab the next thread before possibly
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* destroying the link entry:
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*/
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pthread_next = TAILQ_NEXT(pthread, pqe);
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/*
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* If this thread is waiting for a child
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* process to complete, wake it up:
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*/
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if (pthread->state == PS_WAIT_WAIT) {
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/* Make the thread runnable: */
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PTHREAD_NEW_STATE(pthread,PS_RUNNING);
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/* Return the signal number: */
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pthread->signo = sig;
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}
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}
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}
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/*
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* POSIX says that pending SIGCONT signals are
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* discarded when one of these signals occurs.
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*/
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if (sig == SIGTSTP || sig == SIGTTIN || sig == SIGTTOU) {
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/*
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* Enter a loop to discard pending SIGCONT
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* signals:
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*/
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TAILQ_FOREACH(pthread, &_thread_list, tle) {
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sigdelset(&pthread->sigpend,SIGCONT);
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}
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}
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/*
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* Enter a loop to look for threads that have the signal
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* unmasked. POSIX specifies that a thread in a sigwait
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* will get the signal over any other threads. Second
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* preference will be threads in in a sigsuspend. If
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* none of the above, then the signal is delivered to the
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* first thread we find. Note that if a custom handler
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* is not installed, the signal only affects threads in
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* sigwait.
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*/
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suspended_thread = NULL;
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signaled_thread = NULL;
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if ((_thread_sigact[sig - 1].sa_handler == SIG_IGN) ||
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(_thread_sigact[sig - 1].sa_handler == SIG_DFL))
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handler_installed = 0;
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else
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handler_installed = 1;
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for (pthread = TAILQ_FIRST(&_waitingq);
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pthread != NULL; pthread = pthread_next) {
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/*
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* Grab the next thread before possibly destroying
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* the link entry.
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*/
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pthread_next = TAILQ_NEXT(pthread, pqe);
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if ((pthread->state == PS_SIGWAIT) &&
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sigismember(pthread->data.sigwait, sig)) {
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/* Change the state of the thread to run: */
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PTHREAD_NEW_STATE(pthread,PS_RUNNING);
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/* Return the signal number: */
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pthread->signo = sig;
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/*
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* POSIX doesn't doesn't specify which thread
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* will get the signal if there are multiple
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* waiters, so we give it to the first thread
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* we find.
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*
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* Do not attempt to deliver this signal
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* to other threads.
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*/
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return (NULL);
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}
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else if ((handler_installed != 0) &&
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!sigismember(&pthread->sigmask, sig)) {
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if (pthread->state == PS_SIGSUSPEND) {
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if (suspended_thread == NULL)
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suspended_thread = pthread;
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} else if (signaled_thread == NULL)
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signaled_thread = pthread;
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}
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}
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/*
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* Only perform wakeups and signal delivery if there is a
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* custom handler installed:
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*/
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if (handler_installed != 0) {
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/*
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* If we didn't find a thread in the waiting queue,
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* check the all threads queue:
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*/
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if (suspended_thread == NULL &&
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signaled_thread == NULL) {
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/*
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* Enter a loop to look for other threads
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* capable of receiving the signal:
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*/
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TAILQ_FOREACH(pthread, &_thread_list, tle) {
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if (!sigismember(&pthread->sigmask,
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sig)) {
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signaled_thread = pthread;
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break;
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}
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}
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}
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if (suspended_thread == NULL &&
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signaled_thread == NULL)
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/*
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* Add it to the set of signals pending
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* on the process:
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*/
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sigaddset(&_process_sigpending, sig);
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else {
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/*
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* We only deliver the signal to one thread;
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* give preference to the suspended thread:
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*/
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if (suspended_thread != NULL)
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pthread = suspended_thread;
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else
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pthread = signaled_thread;
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/*
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* Perform any state changes due to signal
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* arrival:
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*/
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thread_sig_check_state(pthread, sig);
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return (pthread);
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}
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}
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}
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/* Returns nothing. */
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return (NULL);
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}
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static void
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thread_sig_finish_longjmp(void *arg)
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{
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/*
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* Check to see if the current thread performed a [_]longjmp() out of a
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* signal handler.
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*/
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if ((_thread_run->jmpflags & (JMPFLAGS_LONGJMP | JMPFLAGS__LONGJMP))
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!= 0) {
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_thread_run->jmpflags = JMPFLAGS_NONE;
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_thread_run->continuation = NULL;
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__longjmp(_thread_run->nested_jmp.jmp,
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_thread_run->longjmp_val);
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}
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/*
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* Check to see if the current thread performed a siglongjmp
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* out of a signal handler:
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*/
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else if ((_thread_run->jmpflags & JMPFLAGS_SIGLONGJMP) != 0) {
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_thread_run->jmpflags = JMPFLAGS_NONE;
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_thread_run->continuation = NULL;
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__siglongjmp(_thread_run->nested_jmp.sigjmp,
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_thread_run->longjmp_val);
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}
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}
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static void
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handle_state_change(pthread_t pthread)
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{
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/*
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* We should only need to handle threads whose state was
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* changed to running:
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*/
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if (pthread->state == PS_RUNNING) {
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switch (pthread->oldstate) {
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/*
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* States which do not change when a signal is trapped:
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*/
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case PS_DEAD:
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case PS_DEADLOCK:
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case PS_RUNNING:
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case PS_SIGTHREAD:
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case PS_STATE_MAX:
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break;
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/*
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* States which need to return to critical sections
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* before they can switch contexts:
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*/
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case PS_COND_WAIT:
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case PS_FDLR_WAIT:
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case PS_FDLW_WAIT:
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case PS_FILE_WAIT:
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case PS_JOIN:
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case PS_MUTEX_WAIT:
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/* Indicate that the thread was interrupted: */
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pthread->interrupted = 1;
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/*
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* Defer the [sig|_]longjmp until leaving the critical
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* region:
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*/
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pthread->jmpflags |= JMPFLAGS_DEFERRED;
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/* Set the continuation routine: */
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pthread->continuation = thread_sig_finish_longjmp;
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/* FALLTHROUGH */
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case PS_FDR_WAIT:
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case PS_FDW_WAIT:
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case PS_POLL_WAIT:
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case PS_SELECT_WAIT:
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case PS_SIGSUSPEND:
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case PS_SIGWAIT:
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case PS_SLEEP_WAIT:
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case PS_SPINBLOCK:
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case PS_SUSPENDED:
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case PS_WAIT_WAIT:
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if ((pthread->flags & PTHREAD_FLAGS_IN_WAITQ) != 0) {
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PTHREAD_WAITQ_REMOVE(pthread);
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if (pthread->flags & PTHREAD_FLAGS_IN_WORKQ)
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PTHREAD_WORKQ_REMOVE(pthread);
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}
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break;
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}
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if ((pthread->flags & PTHREAD_FLAGS_IN_PRIOQ) == 0)
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PTHREAD_PRIOQ_INSERT_TAIL(pthread);
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}
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}
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/* Perform thread specific actions in response to a signal: */
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static void
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thread_sig_check_state(pthread_t pthread, int sig)
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{
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/*
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* Process according to thread state:
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*/
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switch (pthread->state) {
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/*
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* States which do not change when a signal is trapped:
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*/
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case PS_COND_WAIT:
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case PS_DEAD:
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case PS_DEADLOCK:
|
|
case PS_FILE_WAIT:
|
|
case PS_JOIN:
|
|
case PS_MUTEX_WAIT:
|
|
case PS_RUNNING:
|
|
case PS_STATE_MAX:
|
|
case PS_SIGTHREAD:
|
|
case PS_SPINBLOCK:
|
|
case PS_SUSPENDED:
|
|
/* Increment the pending signal count. */
|
|
sigaddset(&pthread->sigpend,sig);
|
|
break;
|
|
|
|
case PS_SIGWAIT:
|
|
/* Wake up the thread if the signal is blocked. */
|
|
if (sigismember(pthread->data.sigwait, sig)) {
|
|
/* Change the state of the thread to run: */
|
|
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
|
|
|
|
/* Return the signal number: */
|
|
pthread->signo = sig;
|
|
} else
|
|
/* Increment the pending signal count. */
|
|
sigaddset(&pthread->sigpend,sig);
|
|
break;
|
|
|
|
/*
|
|
* The wait state is a special case due to the handling of
|
|
* SIGCHLD signals.
|
|
*/
|
|
case PS_WAIT_WAIT:
|
|
/*
|
|
* Check for signals other than the death of a child
|
|
* process:
|
|
*/
|
|
if (sig != SIGCHLD)
|
|
/* Flag the operation as interrupted: */
|
|
pthread->interrupted = 1;
|
|
|
|
/* Change the state of the thread to run: */
|
|
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
|
|
|
|
/* Return the signal number: */
|
|
pthread->signo = sig;
|
|
break;
|
|
|
|
/*
|
|
* States that are interrupted by the occurrence of a signal
|
|
* other than the scheduling alarm:
|
|
*/
|
|
case PS_FDLR_WAIT:
|
|
case PS_FDLW_WAIT:
|
|
case PS_FDR_WAIT:
|
|
case PS_FDW_WAIT:
|
|
case PS_POLL_WAIT:
|
|
case PS_SLEEP_WAIT:
|
|
case PS_SELECT_WAIT:
|
|
if ((_thread_sigact[sig - 1].sa_flags & SA_RESTART) == 0) {
|
|
/* Flag the operation as interrupted: */
|
|
pthread->interrupted = 1;
|
|
|
|
if (pthread->flags & PTHREAD_FLAGS_IN_WORKQ)
|
|
PTHREAD_WORKQ_REMOVE(pthread);
|
|
|
|
/* Change the state of the thread to run: */
|
|
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
|
|
|
|
/* Return the signal number: */
|
|
pthread->signo = sig;
|
|
}
|
|
break;
|
|
|
|
case PS_SIGSUSPEND:
|
|
/*
|
|
* Only wake up the thread if there is a handler installed
|
|
* for the signal.
|
|
*/
|
|
if (_thread_sigact[sig - 1].sa_handler != SIG_DFL) {
|
|
/* Change the state of the thread to run: */
|
|
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
|
|
|
|
/* Return the signal number: */
|
|
pthread->signo = sig;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Send a signal to a specific thread (ala pthread_kill): */
|
|
void
|
|
_thread_sig_send(pthread_t pthread, int sig)
|
|
{
|
|
/*
|
|
* Check that the signal is not being ignored:
|
|
*/
|
|
if (_thread_sigact[sig - 1].sa_handler != SIG_IGN) {
|
|
if (pthread->state == PS_SIGWAIT &&
|
|
sigismember(pthread->data.sigwait, sig)) {
|
|
/* Change the state of the thread to run: */
|
|
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
|
|
|
|
/* Return the signal number: */
|
|
pthread->signo = sig;
|
|
} else if (pthread->state != PS_SIGWAIT &&
|
|
!sigismember(&pthread->sigmask, sig)) {
|
|
/* Perform any state changes due to signal arrival: */
|
|
thread_sig_check_state(pthread, sig);
|
|
|
|
#ifndef _NO_UNDISPATCH
|
|
if (_thread_run != pthread) {
|
|
/*
|
|
* Make a note to call the signal handler once
|
|
* the signaled thread is running. This is
|
|
* necessary in order to make sure that the
|
|
* signal is delivered on the correct stack.
|
|
*/
|
|
pthread->undispatched_signals++;
|
|
} else {
|
|
#endif
|
|
/* Call the installed signal handler. */
|
|
_thread_sig_deliver(pthread, sig);
|
|
#ifndef _NO_UNDISPATCH
|
|
}
|
|
#endif
|
|
} else {
|
|
/* Increment the pending signal count. */
|
|
sigaddset(&pthread->sigpend,sig);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Dispatch pending signals to the running thread: */
|
|
void
|
|
_dispatch_signals()
|
|
{
|
|
sigset_t sigset;
|
|
int i;
|
|
|
|
/*
|
|
* Check if there are pending signals for the running
|
|
* thread or process that aren't blocked:
|
|
*/
|
|
sigset = _thread_run->sigpend;
|
|
SIGSETOR(sigset, _process_sigpending);
|
|
SIGSETNAND(sigset, _thread_run->sigmask);
|
|
if (SIGNOTEMPTY(sigset)) {
|
|
/*
|
|
* Enter a loop to calculate deliverable pending signals
|
|
* before actually delivering them. The pending signals
|
|
* must be removed from the pending signal sets before
|
|
* calling the signal handler because the handler may
|
|
* call library routines that again check for and deliver
|
|
* pending signals.
|
|
*/
|
|
for (i = 1; i < NSIG; i++) {
|
|
/*
|
|
* Check that a custom handler is installed
|
|
* and if the signal is not blocked:
|
|
*/
|
|
if (_thread_sigact[i - 1].sa_handler != SIG_DFL &&
|
|
_thread_sigact[i - 1].sa_handler != SIG_IGN &&
|
|
sigismember(&sigset, i)) {
|
|
if (sigismember(&_thread_run->sigpend,i))
|
|
/* Clear the thread pending signal: */
|
|
sigdelset(&_thread_run->sigpend,i);
|
|
else
|
|
/* Clear the process pending signal: */
|
|
sigdelset(&_process_sigpending,i);
|
|
}
|
|
else
|
|
/* Remove the signal if it can't be handled: */
|
|
sigdelset(&sigset, i);
|
|
}
|
|
|
|
/* Now deliver the signals: */
|
|
for (i = 1; i < NSIG; i++) {
|
|
if (sigismember(&sigset, i))
|
|
/* Deliver the signal to the running thread: */
|
|
_thread_sig_deliver(_thread_run, i);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Deliver a signal to a thread: */
|
|
void
|
|
_thread_sig_deliver(pthread_t pthread, int sig)
|
|
{
|
|
sigset_t mask;
|
|
pthread_t pthread_saved;
|
|
jmp_buf jb, *saved_sighandler_jmp_buf;
|
|
|
|
/*
|
|
* Check that a custom handler is installed
|
|
* and if the signal is not blocked:
|
|
*/
|
|
if (_thread_sigact[sig - 1].sa_handler != SIG_DFL &&
|
|
_thread_sigact[sig - 1].sa_handler != SIG_IGN) {
|
|
/* Save the current thread: */
|
|
pthread_saved = _thread_run;
|
|
|
|
/* Save the threads signal mask: */
|
|
mask = pthread->sigmask;
|
|
|
|
/*
|
|
* Add the current signal and signal handler
|
|
* mask to the thread's current signal mask:
|
|
*/
|
|
SIGSETOR(pthread->sigmask, _thread_sigact[sig - 1].sa_mask);
|
|
sigaddset(&pthread->sigmask, sig);
|
|
|
|
/* Current thread inside critical region? */
|
|
if (_thread_run->sig_defer_count > 0)
|
|
pthread->sig_defer_count++;
|
|
|
|
/* Increment the number of nested signals being handled. */
|
|
pthread->signal_nest_level++;
|
|
|
|
/*
|
|
* The jump buffer is allocated off the stack and the current
|
|
* jump buffer is saved. If the signal handler tries to
|
|
* [sig|_]longjmp(), our version of [sig|_]longjmp() will copy
|
|
* the user supplied jump buffer into
|
|
* _thread_run->nested_jmp.[sig]jmp and _longjmp() back to here.
|
|
*/
|
|
saved_sighandler_jmp_buf = pthread->sighandler_jmp_buf;
|
|
pthread->sighandler_jmp_buf = &jb;
|
|
|
|
_thread_run = pthread;
|
|
|
|
if (_setjmp(jb) == 0) {
|
|
/*
|
|
* Dispatch the signal via the custom signal
|
|
* handler:
|
|
*/
|
|
(*(_thread_sigact[sig - 1].sa_handler))(sig);
|
|
}
|
|
|
|
_thread_run = pthread_saved;
|
|
|
|
pthread->sighandler_jmp_buf = saved_sighandler_jmp_buf;
|
|
|
|
/* Decrement the signal nest level. */
|
|
pthread->signal_nest_level--;
|
|
|
|
/* Current thread inside critical region? */
|
|
if (_thread_run->sig_defer_count > 0)
|
|
pthread->sig_defer_count--;
|
|
|
|
/* Restore the threads signal mask: */
|
|
pthread->sigmask = mask;
|
|
}
|
|
}
|
|
#endif
|