RTT::Logger Class Reference

A simple logging class to debug/ analyse what is going on in the Orocos system. More...

#include <rtt/Logger.hpp>

List of all members.

Classes
struct	In
	Notify the Logger in which 'module' the message occured. More...
Public Types
enum	LogLevel {   Never = 0, Fatal, Critical, Error,   Warning, Info, Debug, RealTime }
	Enumerate all log-levels from absolute silence to everything. More...
typedef std::ostream &(*	LogFunction )(std::ostream &)
	Function signature of the functions that influence the log stream.
Public Member Functions
TimeService::ticks	getReferenceTime () const
	Function to get the loggers starting timestamp.
void	allowRealTime ()
	Allow messages of the LogLevel 'RealTime' to appear on the console.
void	disallowRealTime ()
	Disallow messages of the LogLevel 'RealTime' to appear on the console.
void	mayLogStdOut (bool tf)
	Toggles the flag if the logger may log to the standard output stream.
void	mayLogFile (bool tf)
	Toggles the flag if the logger may log to the file stream.
Logger &	in (const std::string &modname)
	Inform the Logger of the entry of a module.
Logger &	out (const std::string &modname)
	The counterpart of in().
std::string	getLogModule () const
	Get the name of the current Log generating Module.
void	startup ()
	Print a 'welcome' string in Info and reset log timestamp.
void	shutdown ()
	Print a 'goodbye' string in Info, Flush all streams and stop Logging.
std::string	getLogLine ()
	This method gets all messages upto level Info and can be freely read by the user, removing the line from an internal buffer of Logger.
void	setStdStream (std::ostream &stdos)
	Set the standard output stream.
template<class T >
Logger &	operator<< (T t)
	Send (user defined) data into this logger.
Logger &	operator<< (LogLevel ll)
	Set the loglevel of the incomming messages.
Logger &	operator<< (const std::string &)
	Log a string.
Logger &	operator<< (const char *)
	Log a text message.
Logger &	operator<< (std::ostream &(*pf)(std::ostream &))
	Catch the std::endl and other stream manipulators.
void	setLogLevel (LogLevel ll)
	Set the loglevel of the outgoing (streamed) messages.
LogLevel	getLogLevel () const
	Return the current output loglevel.
void	logflush ()
	Flush log buffers.
void	logendl ()
	Add endl and flush buffers.
void	lognl ()
	Add newline without flushing buffers.
Static Public Member Functions
static std::ostream &	nl (std::ostream &__os)
	Insert a newline ' ' in the ostream.
static std::ostream &	endl (std::ostream &__os)
static std::ostream &	flush (std::ostream &__os)
	Flush the output stream.
static Logger *	Instance (std::ostream &str=std::cerr)
	Get the singleton logger.
static void	Release ()
	Delete the singleton logger.
static Logger &	log ()
	As Instance(), but more userfriendly.
static Logger &	log (LogLevel ll)
	As log(), but also specify the LogLevel of the next message.

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Detailed Description

A simple logging class to debug/ analyse what is going on in the Orocos system.

You MUST NOT use this logger in a HARD realtime task or thread.

You can disable all logging at compile time by defining OROBLD_DISABLE_LOGGING (not advised for normal usage). This class can log to a console, and/or to a file and/or to an internal buffer which may be emptied by another class. This is decided upon compile time and can not be changed during runtime. Both printf/iostream are supported.

Example Usage :

     Logger::log() << Logger::Error << "An error Occured !" << Logger::endl;
     Logger::log() << Logger::Debug << "All debug info ..." << Logger::endl;
     * 

When the application is started, set the displayed loglevel with setLogLevel() with a LogLevel parameter. The default is Warning. Set the desired log streams ( a file or std output ) with logToStream() and setStdStream(). Additionally, an orocos.log which is always logs at log level 'Info'.

If you set an environment variable ORO_LOGLEVEL=0..6, this value will be used to determine the output level until overriden by the application (if so). The ORO_LOGLEVEL has the same effect on the 'orocos.log' file, but can not lower it below "Info".

Warning:

Use Logger::RealTime to log from real-time threads. As long as the output LogLevel is 6 or lower, these messages will not appear and do no harm to real-time performance. You need to call

Logger::log().allowRealTime(); 

once in your program to confirm this choice. AGAIN: THIS WILL BREAK REAL-TIME PERFORMANCE.

Definition at line 93 of file Logger.hpp.

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Member Enumeration Documentation

enum RTT::Logger::LogLevel

Enumerate all log-levels from absolute silence to everything.

Warning:

If you enable 'RealTime' logging, this may break realtime performance. Use With Care and NOT on production systems.

See also:

allowRealTime()

Definition at line 111 of file Logger.hpp.

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Member Function Documentation

Logger& RTT::Logger::in

(

const std::string &

modname

)

Inform the Logger of the entry of a module.

See also:

In. Use Logger::In(modname) for management.

static Logger* RTT::Logger::Instance

(

std::ostream &

str = std::cerr

)

[static]

Get the singleton logger.

Postcondition:

If the singleton did not already exist then it is created and associated with the given ostream. If the singleton already existed then no change occurs (and the singleton remains associated with its existing ostream).

void RTT::Logger::logendl

(

)

Add endl and flush buffers.

Will always log at least one line.

void RTT::Logger::logflush

(

)

Flush log buffers.

May log nothing if empty.

void RTT::Logger::lognl

(

)

Add newline without flushing buffers.

If you need to log a lot of lines, this is advised with a flush or endl at the end.

static std::ostream& RTT::Logger::nl

(

std::ostream &

__os

)

[static]

Insert a newline '
' in the ostream.

(Why is this not in the standard ?)

Logger& RTT::Logger::operator<<

(

const char *

)

Log a text message.

This is equivalent to the templated operator<<, but reduces code size since it is compiled only once.

Logger& RTT::Logger::operator<<

(

const std::string &

)

Log a string.

This is equivalent to the templated operator<<, but reduces code size since it is compiled only once.

template<class T >

Logger & RTT::Logger::operator<<

(

T

t

)

[inline]

Send (user defined) data into this logger.

All data with lower priority than the current loglevel will be discarded. If any loglevel (thus in or out) is set to Never, it will never be displayed. You must flush() or end with std::endl to get the log's output in your file or display.

Definition at line 16 of file Logger.inl.

Logger& RTT::Logger::out

(

const std::string &

modname

)

The counterpart of in().

See also:

In. Use Logger::In(modname) for management.

void RTT::Logger::setLogLevel

(

LogLevel

ll

)

Set the loglevel of the outgoing (streamed) messages.

All messages with this level or higher importance will be displayed. For example, setting to Logger::Debug will print everyting, setting to Logger::Critical will only print critical or fatal errors.

void RTT::Logger::setStdStream

(

std::ostream &

stdos

)

Set the standard output stream.

(default is cerr).

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The documentation for this class was generated from the following files:

• rtt/Logger.hpp
• rtt/Logger.inl