76 lines
2.6 KiB
C
76 lines
2.6 KiB
C
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/****************************************************************************
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* libs/libc/semaphore/sem_close.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <nuttx/semaphore.h>
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#ifdef CONFIG_FS_NAMED_SEMAPHORES
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* Name: sem_close
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*
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* Description:
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* This function is called to indicate that the calling task is finished
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* with the specified named semaphore, 'sem'. The sem_close() deallocates
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* any system resources allocated by the system for this named semaphore.
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*
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* If the semaphore has not been removed with a call to sem_unlink(), then
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* sem_close() has no effect on the named semaphore. However, when the
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* named semaphore has been fully unlinked, the semaphore will vanish when
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* the last task closes it.
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*
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* Input Parameters:
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* sem - semaphore descriptor
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*
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* Returned Value:
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* 0 (OK), or -1 (ERROR) if unsuccessful.
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*
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* Assumptions:
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* - Care must be taken to avoid risking the deletion of a semaphore that
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* another calling task has already locked.
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* - sem_close must not be called for an un-named semaphore
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*
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****************************************************************************/
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int sem_close(FAR sem_t *sem)
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{
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int ret;
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ret = nxsem_close(sem);
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if (ret < 0)
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{
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set_errno(-ret);
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return ERROR;
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}
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return ret;
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}
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#endif /* CONFIG_FS_NAMED_SEMAPHORES */
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