90 lines
3.3 KiB
C
90 lines
3.3 KiB
C
|
/************************************************************
|
||
|
|
* dev_null.c
|
||
|
|
*
|
||
|
|
* Copyright (C) 2007 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 Gregory Nutt 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 devnull_read(struct file *, char *, size_t);
|
||
|
|
static ssize_t devnull_write(struct file *, const char *, size_t);
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Private Data
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
static struct file_operations devnull_fops =
|
||
|
|
{
|
||
|
|
.read = devnull_read,
|
||
|
|
.write = devnull_write,
|
||
|
|
};
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Private Functions
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
static ssize_t devnull_read(struct file *filp, char *buffer, size_t len)
|
||
|
|
{
|
||
|
|
return 0; /* Return EOF */
|
||
|
|
}
|
||
|
|
|
||
|
|
static ssize_t devnull_write(struct file *filp, const char *buffer, size_t len)
|
||
|
|
{
|
||
|
|
return len; /* Say that everything was written */
|
||
|
|
}
|
||
|
|
|
||
|
|
/************************************************************
|
||
|
|
* Public Functions
|
||
|
|
************************************************************/
|
||
|
|
|
||
|
|
void devnull_register(void)
|
||
|
|
{
|
||
|
|
(void)register_inode("/dev/null", &devnull_fops, 0666, NULL);
|
||
|
|
}
|