summaryrefslogtreecommitdiff
path: root/nuttx/examples/ostest/sem.c
diff options
context:
space:
mode:
authorpatacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>2007-02-17 23:21:28 +0000
committerpatacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>2007-02-17 23:21:28 +0000
commite3940eb2080711edac189cca3f642ee89dc215f2 (patch)
tree1c390958fae49e34dce698b175487e6d4681e540 /nuttx/examples/ostest/sem.c
parent2223612deb2cc6322992f8595b6d6f86fcb53ae1 (diff)
downloadpx4-nuttx-e3940eb2080711edac189cca3f642ee89dc215f2.tar.gz
px4-nuttx-e3940eb2080711edac189cca3f642ee89dc215f2.tar.bz2
px4-nuttx-e3940eb2080711edac189cca3f642ee89dc215f2.zip
NuttX RTOS
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/examples/ostest/sem.c')
-rw-r--r--nuttx/examples/ostest/sem.c238
1 files changed, 238 insertions, 0 deletions
diff --git a/nuttx/examples/ostest/sem.c b/nuttx/examples/ostest/sem.c
new file mode 100644
index 000000000..0b532982d
--- /dev/null
+++ b/nuttx/examples/ostest/sem.c
@@ -0,0 +1,238 @@
+/***********************************************************************
+ * sem.c
+ *
+ * Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * 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. Neither the name Gregory Nutt nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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 <sys/types.h>
+#include <stdio.h>
+#include <pthread.h>
+#include <semaphore.h>
+#include <sched.h>
+#include "ostest.h"
+
+#ifndef NULL
+# define NULL (void*)0
+#endif
+
+static sem_t sem;
+
+static void *waiter_func(void *parameter)
+{
+ int id = (int)parameter;
+ int status;
+ int value;
+
+ printf("%s: Thread %d Started\n", __FUNCTION__, id);
+
+ /* Take the semaphore */
+
+ status = sem_getvalue(&sem, &value);
+ if (status < 0)
+ {
+ printf("%s: ERROR thread %d could not get semaphore value\n", __FUNCTION__, id);
+ }
+ else
+ {
+ printf("%s: Thread %d initial semaphore value = %d\n", __FUNCTION__, id, value);
+ }
+
+ printf("%s: Thread %d aiting on semaphore\n", __FUNCTION__, id);
+ status = sem_wait(&sem);
+ if (status != 0)
+ {
+ printf("%s: ERROR thread %d sem_wait failed\n", __FUNCTION__, id);
+ }
+ printf("%s: Thread %d awakened\n", __FUNCTION__, id);
+
+ status = sem_getvalue(&sem, &value);
+ if (status < 0)
+ {
+ printf("%s: ERROR thread %d could not get semaphore value\n", __FUNCTION__, id);
+ }
+ else
+ {
+ printf("%s: Thread %d new semaphore value = %d\n", __FUNCTION__, id, value);
+ }
+
+ printf("%s: Thread %d done\n", __FUNCTION__, id);
+ return NULL;
+}
+
+static void *poster_func(void *parameter)
+{
+ int id = (int)parameter;
+ int status;
+ int value;
+
+ printf("%s: Thread %d started\n", __FUNCTION__, id);
+
+ /* Take the semaphore */
+
+ do
+ {
+ status = sem_getvalue(&sem, &value);
+ if (status < 0)
+ {
+ printf("%s: ERROR thread %d could not get semaphore value\n", __FUNCTION__, id);
+ }
+ else
+ {
+ printf("%s: Thread %d semaphore value = %d\n", __FUNCTION__, id, value);
+ }
+
+ if (value < 0)
+ {
+ printf("%s: Thread %d posting semaphore\n", __FUNCTION__, id);
+ status = sem_post(&sem);
+ if (status != 0)
+ {
+ printf("%s: ERROR thread %d sem_wait failed\n", __FUNCTION__, id);
+ }
+
+ pthread_yield();
+
+ status = sem_getvalue(&sem, &value);
+ if (status < 0)
+ {
+ printf("%s: ERROR thread %d could not get semaphore value\n", __FUNCTION__, id);
+ }
+ else
+ {
+ printf("%s: Thread %d new semaphore value = %d\n", __FUNCTION__, id, value);
+ }
+ }
+ }
+ while (value < 0);
+
+ printf("%s: Thread %d done\n", __FUNCTION__, id);
+ return NULL;
+
+}
+
+void sem_test(void)
+{
+ pthread_t waiter_thread1;
+ pthread_t waiter_thread2;
+ pthread_t poster_thread;
+ struct sched_param sparam;
+ int prio_min;
+ int prio_max;
+ int prio_mid;
+ pthread_attr_t attr;
+ int status;
+
+ printf("%s: Initializing semaphore to 0\n", __FUNCTION__);
+ sem_init(&sem, 0, 0);
+
+ /* Start two waiter thread instances */
+
+ printf("%s: Starting waiter thread 1\n", __FUNCTION__);
+ status = pthread_attr_init(&attr);
+ if (status != OK)
+ {
+ printf("%s: pthread_attr_init failed, status=%d\n", __FUNCTION__, status);
+ }
+
+ prio_min = sched_get_priority_min(SCHED_FIFO);
+ prio_max = sched_get_priority_max(SCHED_FIFO);
+ prio_mid = (prio_min + prio_max) / 2;
+
+ sparam.sched_priority = (prio_mid + prio_max) / 2;
+ status = pthread_attr_setschedparam(&attr,&sparam);
+ if (status != OK)
+ {
+ printf("%s: pthread_attr_setschedparam failed, status=%d\n", __FUNCTION__, status);
+ }
+ else
+ {
+ printf("%s: Set thread 1 priority to %d\n", __FUNCTION__, sparam.sched_priority);
+ }
+
+ status = pthread_create(&waiter_thread1, &attr, waiter_func, (void*)1);
+ if (status != 0)
+ {
+ printf("%s: Error in thread 1 creation, status=%d\n", __FUNCTION__, status);
+ }
+
+ printf("%s: Starting waiter thread 2\n", __FUNCTION__);
+ status = pthread_attr_init(&attr);
+ if (status != 0)
+ {
+ printf("%s: pthread_attr_init failed, status=%d\n", __FUNCTION__, status);
+ }
+
+ sparam.sched_priority = prio_mid;
+ status = pthread_attr_setschedparam(&attr,&sparam);
+ if (status != OK)
+ {
+ printf("%s: pthread_attr_setschedparam failed, status=%d\n", __FUNCTION__, status);
+ }
+ else
+ {
+ printf("%s: Set thread 2 priority to %d\n", __FUNCTION__, sparam.sched_priority);
+ }
+
+ status = pthread_create(&waiter_thread2, &attr, waiter_func, (void*)2);
+ if (status != 0)
+ {
+ printf("%s: Error in thread 2 creation, status=%d\n", __FUNCTION__, status);
+ }
+
+ printf("%s: Starting poster thread 3\n", __FUNCTION__);
+ status = pthread_attr_init(&attr);
+ if (status != 0)
+ {
+ printf("%s: pthread_attr_init failed, status=%d\n", __FUNCTION__, status);
+ }
+
+ sparam.sched_priority = (prio_min + prio_mid) / 2;
+ status = pthread_attr_setschedparam(&attr,&sparam);
+ if (status != OK)
+ {
+ printf("%s: pthread_attr_setschedparam failed, status=%d\n", __FUNCTION__, status);
+ }
+ else
+ {
+ printf("%s: Set thread 3 priority to %d\n", __FUNCTION__, sparam.sched_priority);
+ }
+
+ status = pthread_create(&poster_thread, &attr, poster_func, (void*)3);
+ if (status != 0)
+ {
+ printf("%s: Error in thread 3 creation, status=%d\n", __FUNCTION__, status);
+ }
+
+ pthread_join(waiter_thread1, NULL);
+ pthread_join(waiter_thread2, NULL);
+ pthread_join(poster_thread, NULL);
+}