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-rw-r--r--lib/libc_r/uthread/uthread_cond.c293
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diff --git a/lib/libc_r/uthread/uthread_cond.c b/lib/libc_r/uthread/uthread_cond.c
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+++ b/lib/libc_r/uthread/uthread_cond.c
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+/*
+ * Copyright (c) 1995 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 <stdlib.h>
+#include <errno.h>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+int
+pthread_cond_init(pthread_cond_t * cond, const pthread_condattr_t * cond_attr)
+{
+ enum pthread_cond_type type;
+ int rval = 0;
+
+ /*
+ * Check if a pointer to a condition variable attribute structure was
+ * passed by the caller:
+ */
+ if (cond_attr != NULL) {
+ /* Default to a fast condition variable: */
+ type = cond_attr->c_type;
+ } else {
+ /* Default to a fast condition variable: */
+ type = COND_TYPE_FAST;
+ }
+
+ /* Process according to condition variable type: */
+ switch (type) {
+ /* Fast condition variable: */
+ case COND_TYPE_FAST:
+ /* Nothing to do here. */
+ break;
+
+ /* Trap invalid condition variable types: */
+ default:
+ /* Return an invalid argument error: */
+ _thread_seterrno(_thread_run, EINVAL);
+ rval = -1;
+ break;
+ }
+
+ /* Check for no errors: */
+ if (rval == 0) {
+ /* Initialise the condition variable structure: */
+ _thread_queue_init(&cond->c_queue);
+ cond->c_flags |= COND_FLAGS_INITED;
+ cond->c_type = type;
+ }
+ /* Return the completion status: */
+ return (rval);
+}
+
+int
+pthread_cond_destroy(pthread_cond_t * cond)
+{
+ int rval = 0;
+
+ /* Process according to condition variable type: */
+ switch (cond->c_type) {
+ /* Fast condition variable: */
+ case COND_TYPE_FAST:
+ /* Nothing to do here. */
+ break;
+
+ /* Trap invalid condition variable types: */
+ default:
+ /* Return an invalid argument error: */
+ _thread_seterrno(_thread_run, EINVAL);
+ rval = -1;
+ break;
+ }
+
+ /* Check for errors: */
+ if (rval == 0) {
+ /* Destroy the contents of the condition structure: */
+ _thread_queue_init(&cond->c_queue);
+ cond->c_flags = 0;
+ }
+ /* Return the completion status: */
+ return (rval);
+}
+
+int
+pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex)
+{
+ int rval = 0;
+ int status;
+
+ /* Block signals: */
+ _thread_kern_sig_block(&status);
+
+ /* Process according to condition variable type: */
+ switch (cond->c_type) {
+ /* Fast condition variable: */
+ case COND_TYPE_FAST:
+ /* Queue the running thread for the condition variable: */
+ _thread_queue_enq(&cond->c_queue, _thread_run);
+
+ /* Unlock the mutex: */
+ pthread_mutex_unlock(mutex);
+
+ /* Schedule the next thread: */
+ _thread_kern_sched_state(PS_COND_WAIT, __FILE__, __LINE__);
+
+ /* Block signals: */
+ _thread_kern_sig_block(NULL);
+
+ /* Lock the mutex: */
+ rval = pthread_mutex_lock(mutex);
+ break;
+
+ /* Trap invalid condition variable types: */
+ default:
+ /* Return an invalid argument error: */
+ _thread_seterrno(_thread_run, EINVAL);
+ rval = -1;
+ break;
+ }
+
+ /* Unblock signals: */
+ _thread_kern_sig_unblock(status);
+
+ /* Return the completion status: */
+ return (rval);
+}
+
+int
+pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex,
+ const struct timespec * abstime)
+{
+ int rval = 0;
+ int status;
+
+ /* Block signals: */
+ _thread_kern_sig_block(&status);
+
+ /* Process according to condition variable type: */
+ switch (cond->c_type) {
+ /* Fast condition variable: */
+ case COND_TYPE_FAST:
+ /* Set the wakeup time: */
+ _thread_run->wakeup_time.ts_sec = abstime->ts_sec;
+ _thread_run->wakeup_time.ts_nsec = abstime->ts_nsec;
+
+ /* Reset the timeout flag: */
+ _thread_run->timeout = 0;
+
+ /* Queue the running thread for the condition variable: */
+ _thread_queue_enq(&cond->c_queue, _thread_run);
+
+ /* Unlock the mutex: */
+ if ((rval = pthread_mutex_unlock(mutex)) != 0) {
+ /*
+ * Cannot unlock the mutex, so remove the running
+ * thread from the condition variable queue:
+ */
+ _thread_queue_deq(&cond->c_queue);
+ } else {
+ /* Schedule the next thread: */
+ _thread_kern_sched_state(PS_COND_WAIT, __FILE__, __LINE__);
+
+ /* Block signals: */
+ _thread_kern_sig_block(NULL);
+
+ /* Lock the mutex: */
+ if ((rval = pthread_mutex_lock(mutex)) != 0) {
+ }
+ /* Check if the wait timed out: */
+ else if (_thread_run->timeout) {
+ /* Return a timeout error: */
+ _thread_seterrno(_thread_run, EAGAIN);
+ rval = -1;
+ }
+ }
+ break;
+
+ /* Trap invalid condition variable types: */
+ default:
+ /* Return an invalid argument error: */
+ _thread_seterrno(_thread_run, EINVAL);
+ rval = -1;
+ break;
+ }
+
+ /* Unblock signals: */
+ _thread_kern_sig_unblock(status);
+
+ /* Return the completion status: */
+ return (rval);
+}
+
+int
+pthread_cond_signal(pthread_cond_t * cond)
+{
+ int rval = 0;
+ int status;
+ pthread_t pthread;
+
+ /* Block signals: */
+ _thread_kern_sig_block(&status);
+
+ /* Process according to condition variable type: */
+ switch (cond->c_type) {
+ /* Fast condition variable: */
+ case COND_TYPE_FAST:
+ /* Bring the next thread off the condition queue: */
+ if ((pthread = _thread_queue_deq(&cond->c_queue)) != NULL) {
+ /* Allow the thread to run: */
+ pthread->state = PS_RUNNING;
+ }
+ break;
+
+ /* Trap invalid condition variable types: */
+ default:
+ /* Return an invalid argument error: */
+ _thread_seterrno(_thread_run, EINVAL);
+ rval = -1;
+ break;
+ }
+
+ /* Unblock signals: */
+ _thread_kern_sig_unblock(status);
+
+ /* Return the completion status: */
+ return (rval);
+}
+
+int
+pthread_cond_broadcast(pthread_cond_t * cond)
+{
+ int rval = 0;
+ int status;
+ pthread_t pthread;
+
+ /* Block signals: */
+ _thread_kern_sig_block(&status);
+
+ /* Process according to condition variable type: */
+ switch (cond->c_type) {
+ /* Fast condition variable: */
+ case COND_TYPE_FAST:
+ /* Enter a loop to bring all threads off the condition queue: */
+ while ((pthread = _thread_queue_deq(&cond->c_queue)) != NULL) {
+ /* Allow the thread to run: */
+ pthread->state = PS_RUNNING;
+ }
+ break;
+
+ /* Trap invalid condition variable types: */
+ default:
+ /* Return an invalid argument error: */
+ _thread_seterrno(_thread_run, EINVAL);
+ rval = -1;
+ break;
+ }
+
+ /* Unblock signals: */
+ _thread_kern_sig_unblock(status);
+
+ /* Return the completion status: */
+ return (rval);
+}
+#endif
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