incubator-nuttx/include/nuttx/syslog/ramlog.h

209 lines
7.7 KiB
C

/****************************************************************************
* include/nuttx/syslog/ramlog.h
* The RAM logging driver
*
* Copyright (C) 2012, 2014-2015 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.
*
****************************************************************************/
/* The RAM logging driver is a driver that was intended to support debugging
* output (syslogging) when the normal serial output is not available. For
* example, if you are using a Telnet or USB serial console, the debug
* output will get lost.
*
* The RAM logging driver is similar to a pipe in that it saves the
* debugging output in a FIFO in RAM. It differs from a pipe in numerous
* details as needed to support logging.
*
* This driver is built when CONFIG_RAMLOG is defined in the Nuttx
* configuration.
*/
#ifndef __INCLUDE_NUTTX_SYSLOG_RAMLOG_H
#define __INCLUDE_NUTTX_SYSLOG_RAMLOG_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/syslog/syslog.h>
#ifdef CONFIG_RAMLOG
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* CONFIG_RAMLOG - Enables the RAM logging feature
* CONFIG_RAMLOG_CONSOLE - Use the RAM logging device as a system console.
* If this feature is enabled (along with CONFIG_DEV_CONSOLE), then all
* console output will be re-directed to a circular buffer in RAM. This
* is useful, for example, if the only console is a Telnet console. Then
* in that case, console output from non-Telnet threads will go to the
* circular buffer and can be viewed using the NSH 'dmesg' command.
* CONFIG_RAMLOG_SYSLOG - Use the RAM logging device for the syslogging
* interface. If this feature is enabled (along with CONFIG_SYSLOG),
* then all debug output (only) will be re-directed to the circular
* buffer in RAM. This RAM log can be view from NSH using the 'dmesg'
* command. NOTE: Unlike the limited, generic character driver SYSLOG
* device, the RAMLOG *can* be used to generate debug output from interrupt
* level handlers.
* CONFIG_RAMLOG_NPOLLWAITERS - The number of threads than can be waiting
* for this driver on poll(). Default: 4
*
* If CONFIG_RAMLOG_CONSOLE or CONFIG_RAMLOG_SYSLOG is selected, then the
* following may also be provided:
*
* CONFIG_RAMLOG_BUFSIZE - Size of the console RAM log. Default: 1024
*/
#ifndef CONFIG_DEV_CONSOLE
# undef CONFIG_RAMLOG_CONSOLE
#endif
#ifndef CONFIG_SYSLOG
# undef CONFIG_RAMLOG_SYSLOG
#endif
#if defined(CONFIG_RAMLOG_SYSLOG) && !defined(CONFIG_SYSLOG_DEVPATH)
# define CONFIG_SYSLOG_DEVPATH "/dev/ramlog"
#endif
#ifndef CONFIG_RAMLOG_NPOLLWAITERS
# define CONFIG_RAMLOG_NPOLLWAITERS 4
#endif
#ifndef CONFIG_SYSLOG
# undef CONFIG_RAMLOG_SYSLOG
#endif
#ifndef CONFIG_RAMLOG_BUFSIZE
# define CONFIG_RAMLOG_BUFSIZE 1024
#endif
/* The normal behavior of the RAM log when used as a SYSLOG is to return
* end-of-file if there is no data in the RAM log (rather than blocking until
* data is available). That allows you to 'cat' the SYSLOG with no ill
* consequences.
*/
#ifdef CONFIG_SYSLOG
# undef CONFIG_RAMLOG_NONBLOCKING
# define CONFIG_RAMLOG_NONBLOCKING 1
#endif
/* When used as a console or syslogging device, the RAM log will pre-pend
* line-feeds with carriage returns.
*/
#if defined(CONFIG_RAMLOG_CONSOLE) || defined(CONFIG_RAMLOG_SYSLOG)
# undef CONFIG_RAMLOG_CRLF
# define CONFIG_RAMLOG_CRLF 1
#endif
/****************************************************************************
* Public Data
****************************************************************************/
#ifndef __ASSEMBLY__
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: ramlog_register
*
* Description:
* Create the RAM logging device and register it at the specified path.
* Mostly likely this path will be /dev/console.
*
* This interface is not normally used but can be made available is
* someone just wants to tinker with the RAM log as a generic character
* device. Normally both CONFIG_RAMLOG_CONSOLE and CONFIG_RAMLOG_SYSLOG
* would be set (to capture all output in the log) -OR- just
* CONFIG_RAMLOG_SYSLOG would be set to capture debug output only
* in the log.
*
****************************************************************************/
#if !defined(CONFIG_RAMLOG_CONSOLE) && !defined(CONFIG_RAMLOG_SYSLOG)
int ramlog_register(FAR const char *devpath, FAR char *buffer, size_t buflen);
#endif
/****************************************************************************
* Name: ramlog_consoleinit
*
* Description:
* Create the RAM logging device and register it at the specified path.
* Mostly likely this path will be /dev/console.
*
* If CONFIG_RAMLOG_SYSLOG is also defined, then the same RAM logging
* device is also registered at CONFIG_SYSLOG_DEVPATH
*
****************************************************************************/
#ifdef CONFIG_RAMLOG_CONSOLE
int ramlog_consoleinit(void);
#endif
/****************************************************************************
* Name: ramlog_sysloginit
*
* Description:
* Create the RAM logging device and register it at the specified path.
* Mostly likely this path will be CONFIG_SYSLOG_DEVPATH
*
* If CONFIG_RAMLOG_CONSOLE is also defined, then this functionality is
* performed when ramlog_consoleinit() is called.
*
****************************************************************************/
#ifdef CONFIG_RAMLOG_SYSLOG
int ramlog_sysloginit(void);
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* CONFIG_RAMLOG */
#endif /* __INCLUDE_NUTTX_SYSLOG_RAMLOG_H */