incubator-nuttx/drivers/syslog/syslog_write.c

347 lines
10 KiB
C

/****************************************************************************
* drivers/syslog/syslog_write.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/types.h>
#include <assert.h>
#include <nuttx/arch.h>
#include <nuttx/sched.h>
#include <nuttx/syslog/syslog.h>
#include "syslog.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: syslog_safe_to_block
*
* Description:
* Check if it is safe to block for write. If not, the write defaults to a
* non-blocking method.
*
* Input Parameters:
* None.
*
* Returned Value:
* true if it is safe to block; false otherwise.
*
****************************************************************************/
static bool syslog_safe_to_block(void)
{
FAR const struct tcb_s *rtcb;
/* It's not safe to block in interrupts or when executing the idle loop */
if (up_interrupt_context() || sched_idletask())
{
return false;
}
/* It's not safe to block if a signal is being delivered */
rtcb = nxsched_self();
if (rtcb->sigdeliver != NULL)
{
return false;
}
return true;
}
/****************************************************************************
* Name: syslog_default_write
*
* Description:
* This provides a default write method for syslog devices that do not
* support multiple byte writes This functions simply loops, outputting
* one character at a time.
*
* Input Parameters:
* buffer - The buffer containing the data to be output
* buflen - The number of bytes in the buffer
*
* Returned Value:
* On success, the number of characters written is returned. A negated
* errno value is returned on any failure.
*
****************************************************************************/
static ssize_t syslog_default_write(FAR const char *buffer, size_t buflen)
{
size_t nwritten;
if (!syslog_safe_to_block())
{
#ifdef CONFIG_SYSLOG_INTBUFFER
if (up_interrupt_context())
{
for (nwritten = 0; nwritten < buflen; nwritten++)
{
syslog_add_intbuffer(buffer[nwritten]);
}
}
else
#endif
{
int i;
for (i = 0; i < CONFIG_SYSLOG_MAX_CHANNELS; i++)
{
FAR syslog_channel_t *channel = g_syslog_channel[i];
nwritten = 0;
if (channel == NULL)
{
break;
}
#ifdef CONFIG_SYSLOG_IOCTL
if (channel->sc_state & SYSLOG_CHANNEL_DISABLE)
{
continue;
}
#endif
if (channel->sc_ops->sc_write_force != NULL)
{
#ifdef CONFIG_SYSLOG_CRLF
if (!(channel->sc_state & SYSLOG_CHANNEL_DISABLE_CRLF))
{
size_t head;
for (head = 0; head < buflen; head++)
{
ssize_t ret;
/* Check for LF */
if (buffer[head] != '\n')
{
continue;
}
ret = channel->sc_ops->sc_write_force(channel,
buffer + nwritten,
head - nwritten);
if (ret < 0)
{
return ret;
}
ret = channel->sc_ops->sc_write_force(channel,
"\r\n", 2);
if (ret < 0)
{
return ret;
}
nwritten = head + 1;
}
}
#endif
if (nwritten < buflen)
{
ssize_t ret;
ret = channel->sc_ops->sc_write_force(channel,
buffer + nwritten,
buflen - nwritten);
if (ret < 0)
{
return ret;
}
else
{
nwritten += ret;
}
}
}
else
{
DEBUGASSERT(channel->sc_ops->sc_force != NULL);
for (nwritten = 0; nwritten < buflen; nwritten++)
{
#ifdef CONFIG_SYSLOG_CRLF
/* Check for LF */
if (buffer[nwritten] == '\n' &&
!(channel->sc_state & SYSLOG_CHANNEL_DISABLE_CRLF))
{
/* Add CR */
channel->sc_ops->sc_force(channel, '\r');
}
#endif
channel->sc_ops->sc_force(channel, buffer[nwritten]);
}
}
}
}
}
else
{
int i;
for (i = 0; i < CONFIG_SYSLOG_MAX_CHANNELS; i++)
{
FAR syslog_channel_t *channel = g_syslog_channel[i];
nwritten = 0;
if (channel == NULL)
{
break;
}
#ifdef CONFIG_SYSLOG_IOCTL
if (channel->sc_state & SYSLOG_CHANNEL_DISABLE)
{
continue;
}
#endif
if (channel->sc_ops->sc_write != NULL)
{
#ifdef CONFIG_SYSLOG_CRLF
if (!(channel->sc_state & SYSLOG_CHANNEL_DISABLE_CRLF))
{
size_t head;
for (head = 0; head < buflen; head++)
{
size_t ret;
/* Check for LF */
if (buffer[head] != '\n')
{
continue;
}
ret = channel->sc_ops->sc_write(channel,
buffer + nwritten,
head - nwritten);
if (ret < 0)
{
return ret;
}
/* Add CR */
ret = channel->sc_ops->sc_write(channel, "\r\n", 2);
if (ret < 0)
{
return ret;
}
nwritten = head + 1;
}
}
#endif
if (nwritten < buflen)
{
ssize_t ret;
ret = channel->sc_ops->sc_write(channel,
buffer + nwritten,
buflen - nwritten);
if (ret < 0)
{
return ret;
}
else
{
nwritten += ret;
}
}
}
else
{
DEBUGASSERT(channel->sc_ops->sc_putc != NULL);
for (nwritten = 0; nwritten < buflen; nwritten++)
{
#ifdef CONFIG_SYSLOG_CRLF
/* Check for LF */
if (buffer[nwritten] == '\n' &&
!(channel->sc_state & SYSLOG_CHANNEL_DISABLE_CRLF))
{
/* Add CR */
channel->sc_ops->sc_putc(channel, '\r');
}
#endif
channel->sc_ops->sc_putc(channel, buffer[nwritten]);
}
}
}
}
return nwritten;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: syslog_write
*
* Description:
* This is the low-level, multiple character, system logging interface.
*
* Input Parameters:
* buffer - The buffer containing the data to be output
* buflen - The number of bytes in the buffer
*
* Returned Value:
* On success, the number of characters written is returned. A negated
* errno value is returned on any failure.
*
****************************************************************************/
ssize_t syslog_write(FAR const char *buffer, size_t buflen)
{
#ifdef CONFIG_SYSLOG_INTBUFFER
if (!up_interrupt_context() && !sched_idletask())
{
/* Flush any characters that may have been added to the interrupt
* buffer.
*/
syslog_flush_intbuffer(false);
}
#endif
return syslog_default_write(buffer, buflen);
}