nuttx/libc/aio/aio_return.c

119 lines
5.0 KiB
C

/****************************************************************************
* libc/aio/aio_return.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX 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 <aio.h>
#include <assert.h>
#include <errno.h>
#ifdef CONFIG_FS_AIO
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: aio_return
*
* Description:
* The aio_return() function returns the return status associated with
* the aiocb structure referenced by the aiocbp argument. The return
* status for an asynchronous I/O operation is the value that would be
* returned by the corresponding read(), write(), or fsync() function
* call. If the error status for the operation is equal to EINPROGRESS,
* then the return status for the operation is undefined. The aio_return()
* function may be called exactly once to retrieve the return status of
* a given asynchronous operation; thereafter, if the same aiocb structure
* is used in a call to aio_return() or aio_error(), an error may be
* returned. When the aiocb structure referred to by aiocbp is used to
* submit another asynchronous operation, then aio_return() may be
* successfully used to retrieve the return status of that operation.
*
* Input Parameters:
* aiocbp - A pointer to an instance of struct aiocb
*
* Returned Value:
* If the asynchronous I/O operation has completed, then the return
* status, as described for read(), write(), and fsync(), will be
* returned. If the asynchronous I/O operation has not yet completed,
* the results of aio_return() are undefined.
*
* The aio_return() function may fail if:
*
* EINVAL - The aiocbp argument does not refer to an asynchronous
* operation whose return status has not yet been retrieved.
*
****************************************************************************/
ssize_t aio_return(FAR struct aiocb *aiocbp)
{
DEBUGASSERT(aiocbp);
if (aiocbp->aio_result < 0)
{
set_errno((int)-aiocbp->aio_result);
return (ssize_t)ERROR;
}
return aiocbp->aio_result;
}
#endif /* CONFIG_FS_AIO */