walnux/include/nuttx/drivers/drivers.h

288 lines
9.2 KiB
C

/****************************************************************************
* include/nuttx/fs/drivers.h
*
* Copyright (C) 2007-2009, 2011-2013, 2015-2016 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_NUTTX_FS_DRIVERS_H
#define __INCLUDE_NUTTX_FS_DRIVERS_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdbool.h>
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: devnull_register
*
* Description:
* Register /dev/null
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void devnull_register(void);
/****************************************************************************
* Name: devrandom_register
*
* Description:
* Initialize the RNG hardware and register the /dev/random driver.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_DEV_RANDOM
void devrandom_register(void);
#endif
/****************************************************************************
* Name: devurandom_register
*
* Description:
* Register /dev/urandom
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_DEV_URANDOM
void devurandom_register(void);
#endif
/****************************************************************************
* Name: devcrypto_register
*
* Description:
* Register /dev/crypto
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void devcrypto_register(void);
/****************************************************************************
* Name: devzero_register
*
* Description:
* Register /dev/zero
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void devzero_register(void);
/****************************************************************************
* Name: bchdev_register
*
* Description:
* Setup so that it exports the block driver referenced by 'blkdev' as a
* character device 'chardev'
*
****************************************************************************/
int bchdev_register(FAR const char *blkdev, FAR const char *chardev,
bool readonly);
/****************************************************************************
* Name: bchdev_unregister
*
* Description:
* Unregister character driver access to a block device that was created
* by a previous call to bchdev_register().
*
****************************************************************************/
int bchdev_unregister(FAR const char *chardev);
/* Low level, direct access. NOTE: low-level access and character driver access
* are incompatible. One and only one access method should be implemented.
*/
/****************************************************************************
* Name: bchlib_setup
*
* Description:
* Setup so that the block driver referenced by 'blkdev' can be accessed
* similar to a character device.
*
****************************************************************************/
int bchlib_setup(FAR const char *blkdev, bool readonly, FAR void **handle);
/****************************************************************************
* Name: bchlib_teardown
*
* Description:
* Setup so that the block driver referenced by 'blkdev' can be accessed
* similar to a character device.
*
****************************************************************************/
int bchlib_teardown(FAR void *handle);
/****************************************************************************
* Name: bchlib_read
*
* Description:
* Read from the block device set-up by bchlib_setup as if it were a
* character device.
*
****************************************************************************/
ssize_t bchlib_read(FAR void *handle, FAR char *buffer, size_t offset,
size_t len);
/****************************************************************************
* Name: bchlib_write
*
* Description:
* Write to the block device set-up by bchlib_setup as if it were a
* character device.
*
****************************************************************************/
ssize_t bchlib_write(FAR void *handle, FAR const char *buffer, size_t offset,
size_t len);
/****************************************************************************
* Name: pipe2
*
* Description:
* pipe() creates a pair of file descriptors, pointing to a pipe inode,
* and places them in the array pointed to by 'fd'. fd[0] is for reading,
* fd[1] is for writing.
*
* NOTE: mkfifo2 is a special, non-standard, NuttX-only interface. Since
* the NuttX FIFOs are based in in-memory, circular buffers, the ability
* to control the size of those buffers is critical for system tuning.
*
* Input Parameters:
* fd[2] - The user provided array in which to catch the pipe file
* descriptors
* bufsize - The size of the in-memory, circular buffer in bytes.
*
* Returned Value:
* 0 is returned on success; otherwise, -1 is returned with errno set
* appropriately.
*
****************************************************************************/
#if defined(CONFIG_PIPES) && CONFIG_DEV_PIPE_SIZE > 0
int pipe2(int fd[2], size_t bufsize);
#endif
/****************************************************************************
* Name: mkfifo2
*
* Description:
* mkfifo() makes a FIFO device driver file with name 'pathname.' Unlike
* Linux, a NuttX FIFO is not a special file type but simply a device
* driver instance. 'mode' specifies the FIFO's permissions.
*
* Once the FIFO has been created by mkfifo(), any thread can open it for
* reading or writing, in the same way as an ordinary file. However, it
* must have been opened from both reading and writing before input or
* output can be performed. This FIFO implementation will block all
* attempts to open a FIFO read-only until at least one thread has opened
* the FIFO for writing.
*
* If all threads that write to the FIFO have closed, subsequent calls to
* read() on the FIFO will return 0 (end-of-file).
*
* NOTE: mkfifo2 is a special, non-standard, NuttX-only interface. Since
* the NuttX FIFOs are based in in-memory, circular buffers, the ability
* to control the size of those buffers is critical for system tuning.
*
* Input Parameters:
* pathname - The full path to the FIFO instance to attach to or to create
* (if not already created).
* mode - Ignored for now
* bufsize - The size of the in-memory, circular buffer in bytes.
*
* Returned Value:
* 0 is returned on success; otherwise, -1 is returned with errno set
* appropriately.
*
****************************************************************************/
#if defined(CONFIG_PIPES) && CONFIG_DEV_FIFO_SIZE > 0
int mkfifo2(FAR const char *pathname, mode_t mode, size_t bufsize);
#endif
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __INCLUDE_NUTTX_FS_DRIVERS_H */