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diff --git a/lib/libpthread/thread/thr_sig.c b/lib/libpthread/thread/thr_sig.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 <signal.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+/* Static variables: */
+static int volatile yield_on_unlock_dead = 0;
+static int volatile yield_on_unlock_thread = 0;
+static spinlock_t thread_dead_lock = _SPINLOCK_INITIALIZER;
+static spinlock_t thread_link_list_lock = _SPINLOCK_INITIALIZER;
+
+/* Lock the thread list: */
+void
+_lock_thread_list()
+{
+ /* Lock the thread list: */
+ _SPINLOCK(&thread_link_list_lock);
+}
+
+/* Lock the dead thread list: */
+void
+_lock_dead_thread_list()
+{
+ /* Lock the dead thread list: */
+ _SPINLOCK(&thread_dead_lock);
+}
+
+/* Lock the thread list: */
+void
+_unlock_thread_list()
+{
+ /* Unlock the thread list: */
+ _SPINUNLOCK(&thread_link_list_lock);
+
+ /*
+ * Check if a scheduler interrupt occurred while the thread
+ * list was locked:
+ */
+ if (yield_on_unlock_thread) {
+ /* Reset the interrupt flag: */
+ yield_on_unlock_thread = 0;
+
+ /* This thread has overstayed it's welcome: */
+ sched_yield();
+ }
+}
+
+/* Lock the dead thread list: */
+void
+_unlock_dead_thread_list()
+{
+ /* Unlock the dead thread list: */
+ _SPINUNLOCK(&thread_dead_lock);
+
+ /*
+ * Check if a scheduler interrupt occurred while the dead
+ * thread list was locked:
+ */
+ if (yield_on_unlock_dead) {
+ /* Reset the interrupt flag: */
+ yield_on_unlock_dead = 0;
+
+ /* This thread has overstayed it's welcome: */
+ sched_yield();
+ }
+}
+
+void
+_thread_sig_handler(int sig, int code, struct sigcontext * scp)
+{
+ char c;
+ int i;
+ int dispatch = 0;
+ pthread_t pthread;
+
+ /*
+ * Check if the pthread kernel has unblocked signals (or is about to)
+ * and was on its way into a _select when the current
+ * signal interrupted it:
+ */
+ if (_thread_kern_in_select) {
+ /* Cast the signal number to a character variable: */
+ c = sig;
+
+ /*
+ * Write the signal number to the kernel pipe so that it will
+ * be ready to read when this signal handler returns. This
+ * means that the _select call will complete
+ * immediately.
+ */
+ _thread_sys_write(_thread_kern_pipe[1], &c, 1);
+ }
+
+ /* Check if the signal requires a dump of thread information: */
+ if (sig == SIGINFO)
+ /* Dump thread information to file: */
+ _thread_dump_info();
+
+ /* Check if an interval timer signal: */
+ else if (sig == SIGVTALRM) {
+ /* Check if the scheduler interrupt has come at an
+ * unfortunate time which one of the threads is
+ * modifying the thread list:
+ */
+ if (thread_link_list_lock.access_lock)
+ /*
+ * Set a flag so that the thread that has
+ * the lock yields when it unlocks the
+ * thread list:
+ */
+ yield_on_unlock_thread = 1;
+
+ /* Check if the scheduler interrupt has come at an
+ * unfortunate time which one of the threads is
+ * modifying the dead thread list:
+ */
+ if (thread_dead_lock.access_lock)
+ /*
+ * Set a flag so that the thread that has
+ * the lock yields when it unlocks the
+ * dead thread list:
+ */
+ yield_on_unlock_dead = 1;
+
+ /*
+ * Check if the kernel has not been interrupted while
+ * executing scheduler code:
+ */
+ else if (!_thread_kern_in_sched) {
+ /*
+ * Schedule the next thread. This function is not
+ * expected to return because it will do a longjmp
+ * instead.
+ */
+ _thread_kern_sched(scp);
+
+ /*
+ * This point should not be reached, so abort the
+ * process:
+ */
+ PANIC("Returned to signal function from scheduler");
+ }
+ } else {
+ /* Check if a child has terminated: */
+ if (sig == SIGCHLD) {
+ /*
+ * Go through the file list and set all files
+ * to non-blocking again in case the child
+ * set some of them to block. Sigh.
+ */
+ for (i = 0; i < _thread_dtablesize; i++) {
+ /* Check if this file is used: */
+ if (_thread_fd_table[i] != NULL) {
+ /*
+ * Set the file descriptor to
+ * non-blocking:
+ */
+ _thread_sys_fcntl(i, F_SETFL,
+ _thread_fd_table[i]->flags |
+ O_NONBLOCK);
+ }
+ }
+ }
+
+ /*
+ * POSIX says that pending SIGCONT signals are
+ * discarded when one of there signals occurs.
+ */
+ if (sig == SIGTSTP || sig == SIGTTIN || sig == SIGTTOU) {
+ /*
+ * Enter a loop to discard pending SIGCONT
+ * signals:
+ */
+ for (pthread = _thread_link_list;
+ pthread != NULL;
+ pthread = pthread->nxt)
+ sigdelset(&pthread->sigpend,SIGCONT);
+ }
+
+ /* Check if the signal is not being ignored: */
+ if (_thread_sigact[sig - 1].sa_handler != SIG_IGN)
+ /*
+ * Enter a loop to process each thread in the linked
+ * list:
+ */
+ for (pthread = _thread_link_list; pthread != NULL;
+ pthread = pthread->nxt)
+ _thread_signal(pthread,sig);
+
+ /* Dispatch pending signals to the running thread: */
+ _dispatch_signals();
+ }
+
+ /* Returns nothing. */
+ return;
+}
+
+/* Perform thread specific actions in response to a signal: */
+void
+_thread_signal(pthread_t pthread, int sig)
+{
+ pthread_t saved;
+ struct sigaction act;
+
+ /*
+ * Flag the signal as pending. It will be dispatched later.
+ */
+ sigaddset(&pthread->sigpend,sig);
+
+ /*
+ * Process according to thread state:
+ */
+ switch (pthread->state) {
+ /*
+ * States which do not change when a signal is trapped:
+ */
+ case PS_COND_WAIT:
+ case PS_DEAD:
+ case PS_FDLR_WAIT:
+ case PS_FDLW_WAIT:
+ case PS_FILE_WAIT:
+ case PS_JOIN:
+ case PS_MUTEX_WAIT:
+ case PS_RUNNING:
+ case PS_STATE_MAX:
+ case PS_SIGTHREAD:
+ case PS_SUSPENDED:
+ /* Nothing to do here. */
+ 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_FDR_WAIT:
+ case PS_FDW_WAIT:
+ case PS_SLEEP_WAIT:
+ case PS_SIGWAIT:
+ case PS_SELECT_WAIT:
+ if (sig != SIGCHLD ||
+ _thread_sigact[sig - 1].sa_handler != SIG_DFL) {
+ /* 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;
+ }
+}
+
+/* Dispatch pending signals to the running thread: */
+void
+_dispatch_signals()
+{
+ int i;
+
+ /*
+ * Check if there are pending signals for the running
+ * thread that aren't blocked:
+ */
+ if ((_thread_run->sigpend & ~_thread_run->sigmask) != 0)
+ /* Look for all possible 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(&_thread_run->sigpend,i) &&
+ !sigismember(&_thread_run->sigmask,i)) {
+ /* Clear the pending signal: */
+ sigdelset(&_thread_run->sigpend,i);
+
+ /*
+ * Dispatch the signal via the custom signal
+ * handler:
+ */
+ (*(_thread_sigact[i - 1].sa_handler))(i);
+ }
+}
+#endif
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