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/****************************************************************************
* include/aio.h
*
* 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.
*
****************************************************************************/
#ifndef __INCLUDE_AIO_H
#define __INCLUDE_AIO_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <signal.h>
#include <time.h>
#include <nuttx/wqueue.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Work queue support is required. In the flat, embedded build the low-
* priority work queue is required so that the asynchronous I/O does not
* interfere with high priority driver operations. In the protected and
* kernel mode builds, user-space work queue support is required. If these
* pre-requisites are met, then asynchronous I/O support can be enabled with
* CONFIG_LIBC_AIO
*/
#ifdef CONFIG_LIBC_AIO
#ifndef CONFIG_SCHED_WORKQUEUE
# error Asynchronous I/O requiresCONFIG_SCHED_WORKQUEUE
#else
# if defined (CONFIG_BUILD_PROTECTED) || defined(CONFIG_BUILD_KERNEL)
# ifndef CONFIG_SCHED_USRWORK
# error User-space asynchronous I/O requires CONFIG_SCHED_USRWORK
# endif
# else
# ifndef CONFIG_SCHED_LPWORK
# error Flat-build asynchronous I/O requires CONFIG_SCHED_LPWORK
# endif
# endif
#endif
/* Standard Definitions *****************************************************/
/* aio_cancel return values
*
* AIO_ALLDONE - Indicates that none of the requested operations could
* be cancelled since they are already complete.
* AIO_CANCELED - Indicates that all requested operations have been
* cancelled.
* AIO_NOTCANCELED - Indicates that some of the requested operations could
* not be cancelled since they are in progress.
*/
#define AIO_CANCELED 0
#define AIO_ALLDONE 1
#define AIO_NOTCANCELED 2
/* lio_listio element operations
*
* LIO_NOP - Indicates that no transfer is requested.
* LIO_READ - Requests a read operation.
* LIO_WRITE - Requests a write operation.
*/
#define LIO_NOP 0
#define LIO_READ 1
#define LIO_WRITE 2
/* lio_listio modes
*
* LIO_NOWAIT - Indicates that the calling thread is to continue
* execution while the lio_listio() operation is being
* performed, and no notification is given when the
* operation is complete.
* LIO_WAIT - Indicates that the calling thread is to suspend until
* the lio_listio() operation is complete.
*/
#define LIO_NOWAIT 0
#define LIO_WAIT 1
/****************************************************************************
* Type Definitions
****************************************************************************/
struct aiocb
{
/* Standard fields required by POSIX */
struct sigevent aio_sigevent; /* Signal number and value */
FAR volatile void *aio_buf; /* Location of buffer */
off_t aio_offset; /* File offset */
size_t aio_nbytes; /* Length of transfer */
int aio_fildes; /* File descriptor */
int aio_reqprio; /* Request priority offset */
int aio_lio_opcode; /* Operation to be performed */
/* Non-standard, implementation-dependent data */
struct work_s aio_work; /* Used to defer I/O to the work thread */
pid_t aio_pid; /* ID of client to be notify at completion */
volatile ssize_t aio_result; /* Support for aio_error() and aio_return() */
};
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
int aio_cancel(int, FAR struct aiocb *aiocbp);
int aio_error(FAR const struct aiocb *aiocbp);
int aio_fsync(int, FAR struct aiocb *aiocbp);
int aio_read(FAR struct aiocb *aiocbp);
ssize_t aio_return(FAR struct aiocb *aiocbp);
int aio_suspend(FAR const struct aiocb *const list[], int nent,
FAR const struct timespec *timeout);
int aio_write(FAR struct aiocb *aiocbp);
#ifndef CONFIG_PTHREAD_DISABLE
int lio_listio(int mode, FAR struct aiocb *const list[], int nent,
FAR struct sigevent *sig);
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_LIBC_AIO */
#endif /* __INCLUDE_AIO_H */
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