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-rw-r--r--nuttx/sched/pthread_mutexlock.c138
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diff --git a/nuttx/sched/pthread_mutexlock.c b/nuttx/sched/pthread_mutexlock.c
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+/************************************************************
+ * pthread_mutexlock.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.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <pthread.h>
+#include <sched.h>
+#include <errno.h>
+#include <debug.h>
+#include "pthread_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Type Declarations
+ ************************************************************/
+
+/************************************************************
+ * Global Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Function: pthread_mutex_lock
+ *
+ * Description:
+ * Lock a mutex.
+ *
+ * Parameters:
+ * None
+ *
+ * Return Value:
+ * None
+ *
+ * Assumptions:
+ *
+ ************************************************************/
+
+int pthread_mutex_lock(pthread_mutex_t *mutex)
+{
+ int mypid = (int)getpid();
+ int ret = OK;
+
+ dbg("%s: mutex=0x%p\n", __FUNCTION__, mutex);
+
+ if (!mutex)
+ {
+ ret = EINVAL;
+ }
+ else
+ {
+ /* Make sure the semaphore is stable while we make the following
+ * checks. This all needs to be one atomic action.
+ */
+
+ sched_lock();
+
+ /* Does this task already hold the semaphore? */
+
+ if (mutex->pid == mypid)
+ {
+ dbg("%s: Returning EDEADLK\n", __FUNCTION__);
+ ret = EDEADLK;
+ }
+ else
+ {
+ /* Take the semaphore */
+
+ ret = pthread_takesemaphore((sem_t*)&mutex->sem);
+
+ /* If we succussfully obtained the semaphore, then indicate
+ * that we own it.
+ */
+
+ if (!ret)
+ {
+ mutex->pid = mypid;
+ }
+ }
+ sched_unlock();
+ }
+
+ dbg("%s: Returning %d\n", __FUNCTION__, ret);
+ return ret;
+}
+
+
+
+