* drivers/syslog/syslog_write.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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)
{
#ifndef CONFIG_DISABLE_SIGNALS
FAR const struct tcb_s *rtcb;
#endif
if (up_interrupt_context() || sched_idletask())
{
return false;
}
#ifndef CONFIG_DISABLE_SIGNALS
rtcb = nxsched_self();
if (rtcb->sigdeliver != NULL)
{
return false;
}
#endif
return true;
}
* Public Functions
****************************************************************************/
* Name: syslog_write_foreach
*
* 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.
*
****************************************************************************/
ssize_t syslog_write_foreach(FAR const char *buffer,
size_t buflen, bool force)
{
syslog_write_t write;
syslog_putc_t putc;
size_t nwritten = 0;
ssize_t ret;
int i;
for (i = 0; i < CONFIG_SYSLOG_MAX_CHANNELS; i++)
{
FAR syslog_channel_t *channel = g_syslog_channel[i];
if (channel == NULL)
{
break;
}
#ifdef CONFIG_SYSLOG_IOCTL
if (channel->sc_state & SYSLOG_CHANNEL_DISABLE)
{
continue;
}
#endif
write = !force ? channel->sc_ops->sc_write :
channel->sc_ops->sc_write_force;
if (write != NULL)
{
nwritten = 0;
#ifdef CONFIG_SYSLOG_CRLF
if (!(channel->sc_state & SYSLOG_CHANNEL_DISABLE_CRLF))
{
size_t head;
for (head = 0; head < buflen; head++)
{
if (buffer[head] != '\n')
{
continue;
}
ret = write(channel, buffer + nwritten, head - nwritten);
if (ret >= 0)
{
ret = write(channel, "\r\n", 2);
}
if (ret < 0)
{
return ret;
}
nwritten = head + 1;
}
}
#endif
if (nwritten < buflen)
{
ret = write(channel, buffer + nwritten, buflen - nwritten);
if (ret < 0)
{
return ret;
}
else
{
nwritten += ret;
}
}
}
else
{
putc = !force ? channel->sc_ops->sc_putc :
channel->sc_ops->sc_force;
if (putc == NULL)
{
continue;
}
#ifdef CONFIG_SYSLOG_CRLF
if (channel->sc_state & SYSLOG_CHANNEL_DISABLE_CRLF)
#endif
{
for (nwritten = 0; nwritten < buflen; nwritten++)
{
putc(channel, buffer[nwritten]);
}
}
#ifdef CONFIG_SYSLOG_CRLF
else
{
for (nwritten = 0; nwritten < buflen; nwritten++)
{
if (buffer[nwritten] == '\n')
{
putc(channel, '\r');
}
putc(channel, buffer[nwritten]);
}
}
#endif
}
}
return nwritten;
}
* 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)
{
bool force = !syslog_safe_to_block();
#ifdef CONFIG_SYSLOG_INTBUFFER
if (force)
{
syslog_add_intbuffer(buffer, buflen);
return buflen;
}
else
{
* buffer.
*/
syslog_flush_intbuffer(false);
}
#endif
return syslog_write_foreach(buffer, buflen, force);
}