incubator-nuttx/drivers/syslog/syslog_filechannel.c

163 lines
5.3 KiB
C

/****************************************************************************
* drivers/syslog/syslog_filechannel.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/stat.h>
#include <sched.h>
#include <fcntl.h>
#include <nuttx/syslog/syslog.h>
#include "syslog.h"
#ifdef CONFIG_SYSLOG_FILE
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define OPEN_FLAGS (O_WRONLY | O_CREAT | O_APPEND)
#define OPEN_MODE (S_IROTH | S_IRGRP | S_IRUSR | S_IWUSR)
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* SYSLOG channel methods */
static int syslog_file_force(int ch);
/****************************************************************************
* Private Data
****************************************************************************/
/* This structure describes the SYSLOG channel */
static const struct syslog_channel_s g_syslog_file_channel =
{
syslog_dev_putc,
syslog_file_force,
syslog_dev_flush,
#ifdef CONFIG_SYSLOG_WRITE
syslog_dev_write,
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: syslog_file_force
*
* Description:
* A dummy FORCE method
*
****************************************************************************/
static int syslog_file_force(int ch)
{
return ch;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: syslog_file_channel
*
* Description:
* Configure to use a file in a mounted file system at 'devpath' as the
* SYSLOG channel.
*
* This tiny function is simply a wrapper around syslog_dev_initialize()
* and syslog_channel(). It calls syslog_dev_initialize() to configure
* the character file at 'devpath then calls syslog_channel() to use that
* device as the SYSLOG output channel.
*
* File SYSLOG channels differ from other SYSLOG channels in that they
* cannot be established until after fully booting and mounting the target
* file system. This function would need to be called from board-specific
* bring-up logic AFTER mounting the file system containing 'devpath'.
*
* SYSLOG data generated prior to calling syslog_file_channel will, of
* course, not be included in the file.
*
* NOTE interrupt level SYSLOG output will be lost in this case unless
* the interrupt buffer is used.
*
* Input Parameters:
* devpath - The full path to the file to be used for SYSLOG output.
* This may be an existing file or not. If the file exists,
* syslog_file_channel() will append new SYSLOG data to the end of the
* file. If it does not, then syslog_file_channel() will create the
* file.
*
* Returned Value:
* Zero (OK) is returned on success; a negated errno value is returned on
* any failure.
*
****************************************************************************/
int syslog_file_channel(FAR const char *devpath)
{
int ret;
/* Reset the default SYSLOG channel so that we can safely modify the
* SYSLOG device. This is an atomic operation and we should be safe
* after the default channel has been selected.
*
* We disable pre-emption only so that we are not suspended and a lot of
* important debug output is lost while we futz with the channels.
*/
sched_lock();
/* Uninitialize any driver interface that may have been in place */
syslog_dev_uninitialize();
/* Then initialize the file interface */
ret = syslog_dev_initialize(devpath, OPEN_FLAGS, OPEN_MODE);
if (ret < 0)
{
goto errout_with_lock;
}
/* Use the file as the SYSLOG channel. If this fails we are pretty much
* screwed.
*/
ret = syslog_channel(&g_syslog_file_channel);
errout_with_lock:
sched_unlock();
return ret;
}
#endif /* CONFIG_SYSLOG_FILE */