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authorpatacongo <patacongo@7fd9a85b-ad96-42d3-883c-3090e2eb8679>2007-03-23 23:22:22 +0000
committerpatacongo <patacongo@7fd9a85b-ad96-42d3-883c-3090e2eb8679>2007-03-23 23:22:22 +0000
commit0d3a07700aed7de951e274470c41816366cc3b4c (patch)
tree776672757efb51d171d9bd17355fa8cd5053f9ef /nuttx/sched/pthread_once.c
parent757228e92b2f4d04bf48629f2c42d62eed041149 (diff)
Add new pthread_* APIs
git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@134 7fd9a85b-ad96-42d3-883c-3090e2eb8679
Diffstat (limited to 'nuttx/sched/pthread_once.c')
-rw-r--r--nuttx/sched/pthread_once.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/nuttx/sched/pthread_once.c b/nuttx/sched/pthread_once.c
new file mode 100644
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+++ b/nuttx/sched/pthread_once.c
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+/********************************************************************************
+ * pthread_once.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 <nuttx/config.h>
+#include <sys/types.h>
+#include <pthread.h>
+#include <sched.h>
+#include <errno.h>
+#include <debug.h>
+
+/********************************************************************************
+ * Definitions
+ ********************************************************************************/
+
+/********************************************************************************
+ * Private Type Declarations
+ ********************************************************************************/
+
+/********************************************************************************
+ * Global Variables
+ ********************************************************************************/
+
+/********************************************************************************
+ * Private Variables
+ ********************************************************************************/
+
+/********************************************************************************
+ * Private Function Prototypes
+ ********************************************************************************/
+
+/********************************************************************************
+ * Public Functions
+ ********************************************************************************/
+
+/********************************************************************************
+ * Function: pthread_once
+ *
+ * Description:
+ * The first call to pthread_once() by any thread with a given once_control,
+ * will call the init_routine with no arguments. Subsequent calls to
+ * pthread_once() with the same once_control will have no effect. On return
+ * from pthread_once(), init_routine will have completed.
+ *
+ * Parameters:
+ * once_control - Determines if init_routine should be called. once_control
+ * should be declared and intialized as follows:
+ *
+ * pthread_once_t once_control = PTHREAD_ONCE_INIT;
+ *
+ * PTHREAD_ONCE_INIT is defined in pthread.h
+ * init_routine - The initialization routine that will be called once.
+ *
+ * Return Value:
+ * 0 (OK) on success or EINVAL if either once_control or init_routine are invalid
+ *
+ * Assumptions:
+ *
+ ********************************************************************************/
+
+int pthread_once(FAR pthread_once_t *once_control, CODE void (*init_routine)(void))
+{
+ /* Sanity checks */
+
+ if (once_control && init_routine)
+ {
+ /* Prohibit pre-emption while we test and set the once_control */
+
+ sched_lock();
+ if (!*once_control)
+ {
+ *once_control = TRUE;
+
+ /* Call the init_routine with pre-emption enabled. */
+
+ sched_unlock();
+ init_routine();
+ return OK;
+ }
+
+ /* The init_routine has already been called. Restore pre-emption and return */
+
+ sched_unlock();
+ return OK;
+ }
+
+ /* One of the two arguments is NULL */
+
+ return EINVAL;
+}