upstream/1.1.0_cvsrelease/1.1.0_cvs

1 files changed, 109 insertions, 0 deletions

diff --git a/lib/libpthread/pthreads/pthread_join.c b/lib/libpthread/pthreads/pthread_join.c
new file mode 100644
index 000000000000..773098618972
--- /dev/null
+++ b/lib/libpthread/pthreads/pthread_join.c
@@ -0,0 +1,109 @@
+/* ==== pthread_join.c =======================================================
+ * Copyright (c) 1994 by Chris Provenzano, proven@mit.edu
+ * 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 Chris Provenzano.
+ * 4. The name of Chris Provenzano may not be used to endorse or promote 
+ *	  products derived from this software without specific prior written
+ *	  permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``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 CHRIS PROVENZANO 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.
+ *
+ * Description : pthread_join function.
+ *
+ *  1.00 94/01/15 proven
+ *      -Started coding this file.
+ */
+
+#include <pthread.h>
+
+/* ==========================================================================
+ * pthread_join()
+ */
+int pthread_join(pthread_t pthread, void **thread_return)
+{
+	semaphore *lock, *plock;
+	int ret;
+
+
+	plock = &(pthread->lock);
+	while (SEMAPHORE_TEST_AND_SET(plock)) {
+		pthread_yield();
+	}
+
+	/* Check that thread isn't detached already */
+	if (pthread->flags & PF_DETACHED) {
+		SEMAPHORE_RESET(plock);
+		return(ESRCH);
+	} 
+
+	lock = &(pthread_run->lock);
+	while (SEMAPHORE_TEST_AND_SET(lock)) {
+		pthread_yield();
+	}
+
+	/* If OK then queue current thread. */
+	pthread_queue(&(pthread->join_queue), pthread_run);
+
+	SEMAPHORE_RESET(plock);
+	reschedule(PS_JOIN);
+
+	/*
+	 * At this point the thread is locked from the pthread_exit 
+	 * and so are we, so no extra locking is required, but be sure
+	 * to unlock at least ourself.
+	 */
+	if (!(pthread->flags & PF_DETACHED)) {
+		if (thread_return) {
+			*thread_return = pthread->ret;
+		}
+		pthread->flags |= PF_DETACHED;
+		ret = OK;
+	} else {
+		ret = ESRCH;
+	}
+
+	/* Cant do a cleanup until queue is cleared */
+	{
+		struct pthread * next_thread;
+		semaphore * next_lock;
+
+		if (next_thread = pthread_queue_get(&(pthread->join_queue))) {
+			next_lock = &(next_thread->lock);
+			while (SEMAPHORE_TEST_AND_SET(next_lock)) {
+				pthread_yield();
+			}
+			pthread_queue_deq(&(pthread->join_queue)); 
+			next_thread->state = PS_RUNNING;
+			/*
+			 * Thread will wake up in pthread_join(), see the thread
+			 * it was joined to already detached and unlock itself
+			 */
+		} else {
+			SEMAPHORE_RESET(lock);
+		}
+	}
+
+	SEMAPHORE_RESET(plock);
+	return(ret);
+}