100 lines
3.4 KiB
C
100 lines
3.4 KiB
C
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/************************************************************
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* lib_streamsem.c
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*
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* Copyright (C) 2007 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name Gregory Nutt nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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************************************************************/
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/************************************************************
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* Compilation Switches
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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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#if CONFIG_NFILE_STREAMS > 0
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#include <sys/types.h>
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#include <stdlib.h>
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#include <string.h>
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#include <assert.h>
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#include <semaphore.h>
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#include <errno.h>
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#include <nuttx/fs.h>
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#include "lib_internal.h"
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/************************************************************
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* Private types
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************************************************************/
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/************************************************************
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* Private Variables
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************************************************************/
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/************************************************************
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* Public Variables
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************************************************************/
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/************************************************************
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* Private Functions
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************************************************************/
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/************************************************************
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* Public Functions
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************************************************************/
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void stream_semtake(struct streamlist *list)
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{
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/* Take the semaphore (perhaps waiting) */
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while (sem_wait(&list->sl_sem) != 0)
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{
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/* The only case that an error should occr here is if
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* the wait was awakened by a signal.
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*/
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ASSERT(*get_errno_ptr() == EINTR);
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}
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}
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void stream_semgive(struct streamlist *list)
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{
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sem_post(&list->sl_sem);
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}
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#endif /* CONFIG_NFILE_STREAMS */
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