/****************************************************************************
* drivers/dev_null.c
*
* Copyright (C) 2008 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Compilation Switches
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <string.h>
#include <errno.h>
#include <nuttx/fs.h>
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static ssize_t devzero_read(FAR struct file *, FAR char *, size_t);
static ssize_t devzero_write(FAR struct file *, FAR const char *, size_t);
/****************************************************************************
* Private Data
****************************************************************************/
static struct file_operations devzero_fops =
{
0, /* open */
0, /* close */
devzero_read, /* read */
devzero_write, /* write */
0, /* seek */
0 /* ioctl */
};
/****************************************************************************
* Private Functions
****************************************************************************/
static ssize_t devzero_read(FAR struct file *filp, FAR char *buffer, size_t len)
{
memset(buffer, 0, len);
return len;
}
static ssize_t devzero_write(FAR struct file *filp, FAR const char *buffer, size_t len)
{
return len;
}
/****************************************************************************
* Public Functions
****************************************************************************/
void devzero_register(void)
{
(void)register_driver("/dev/zero", &devzero_fops, 0666, NULL);
}
