incubator-nuttx/drivers/syslog/syslog_emergstream.c

115 lines
4.0 KiB
C

/****************************************************************************
* drivers/syslog/syslog_emergtream.c
*
* Copyright (C) 2016-2017 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 <stdio.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/syslog/syslog.h>
#include <nuttx/streams.h>
#include "syslog.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: emergstream_putc
****************************************************************************/
static void emergstream_putc(FAR struct lib_outstream_s *this, int ch)
{
int ret;
/* Try writing until the write was successful or until an irrecoverable
* error occurs.
*/
do
{
/* Write the character to the supported logging device. On failure,
* syslog_putc returns EOF with the errno value set;
*/
ret = syslog_force(ch);
if (ret != EOF)
{
this->nput++;
return;
}
/* The special errno value -EINTR means that syslog_putc() was
* awakened by a signal. This is not a real error and must be
* ignored in this context.
*/
}
while (errno == -EINTR);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: emergstream
*
* Description:
* Initializes a stream for use with the configured emergency syslog
* interface. Only accessible from with the OS SYSLOG logic.
*
* Input Parameters:
* stream - User allocated, uninitialized instance of struct
* lib_outstream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
void emergstream(FAR struct lib_outstream_s *stream)
{
stream->put = emergstream_putc;
stream->flush = lib_noflush;
stream->nput = 0;
}