A simple logger. All classes that want to write to the global log file should inherit from this class. More...

#include <logger.h>

Inheritance diagram for Logger:

[legend]

Public Member Functions
	Logger (std::string label)

std::string	label () const
	Return the object's log label.

void	resetLabel (const std::string &new_label)
	Modify the object's log label.

Static Public Member Functions
static void	setLogFile (std::ostream &stream)
	Set global log destination. More...

static void	reopenLogFile (const std::string &filename)
	If current log is a file (ofstream), reopen it with new filename:

static void	setLogLimit (unsigned int loglines=0, unsigned int warnlines=0, unsigned int errlines=0)
	Set max number of lines of info/warn/err log. More...

static void	sayTime (std::ostream &stream)
	Write current local time to the given stream.

static bool	inError ()
	Return true if any error has been logged (globally since start)

static std::ostream &	err_log (const std::string &label)
	Write a line of error log. More...

static std::ostream &	warn_log (const std::string &label)
	Write a line of warning log. More...

static std::ostream &	log (const std::string &label)
	Write a line of info log. More...

static void	flushLogFile ()

static void	pauseLogging ()
	Disable all log output until next call to Logger::setLogFile.

static double	secondsSince (const TimePoint &t)

static double	secondsTo (const TimePoint &t)

static int64_t	msSince (const TimePoint &t)

static int64_t	msTo (const TimePoint &t)

static bool	hasExpired (const TimePoint &t)
	Return true if current time is after the given TimePoint.

static TimePoint	timeNow ()
	Return current time.

static TimePoint	timeAfter (double s)
	Return current time plus s seconds.

static TimePoint	timeMax ()
	Return a very distant time.

static std::chrono::microseconds	toUs (double t)
	Convert s (seconds) to std::chrono::microseconds.

static std::string	dateString (time_t t=0)
	Return local time, formatted as 2023-10-14T09:38:47+0200.

static std::string	dateString2 (time_t t=0)
	Return local time, formatted as Sat, 14 Oct 2023 09:38:47.

static std::string	createHashKey (unsigned int length=20)
	Return a random string. More...

Protected Member Functions
std::ostream &	errno_log () const
	Write a line of error log after a failed system call has set the global errno to a non-zero value. More...

std::ostream &	err_log () const
	Write a line of error log. More...

std::ostream &	warn_log () const
	Write a line of warning log. More...

std::ostream &	log () const
	Write a line of info log. More...

std::ostream &	dbg_log () const
	Write a line of debug log. More...

Detailed Description

A simple logger. All classes that want to write to the global log file should inherit from this class.

By default, logs will be written to cerr. To log elsewhere, you must call the static function Logger::setLogFile with a stream object (e.g. an std::ofstream or an std::ostringstream) which the logs will be written to. The stream will be used globally. You must make sure the global stream is never destroyed, at least not before Logger::setLogFile has been called with another stream.

Constructor & Destructor Documentation

◆ Logger()

Logger::Logger ( std::string label )

inline

Each object of the Logger class (or its subclasses) have a log label, which will often be thought of as the name of the object.

Member Function Documentation

◆ createHashKey()

std::string Logger::createHashKey ( unsigned int length = 20 )

static

Return a random string.

Create string of length random hex chars from system's random number generator. The length should be a multiple of 4.

◆ dbg_log()

std::ostream& Logger::dbg_log ( ) const

inlineprotected

Write a line of debug log.

Access the current global debug log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

Note! The global debug log stream will be "disabled" (i.e. set to a dummy stream) unless compiler macro TASKRUNNER_LOGDBG is defined.

◆ err_log() [1/2]

std::ostream& Logger::err_log ( ) const

inlineprotected

Write a line of error log.

Access the current global error log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

Note! The global error log stream will be "disabled" (i.e. set to a dummy stream) unless compiler macro TASKRUNNER_LOGERR is defined.

May be used in any non-static member of any subclass. Example:

err_log() << "Child task " << t->label() << " failed.";

◆ err_log() [2/2]

static std::ostream& Logger::err_log ( const std::string & label )

inlinestatic

Write a line of error log.

Access the current global error log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

In non-static members of subclasses to Logger, the method Logger::err_log() should be used instead of this function.

◆ errno_log()

std::ostream & Logger::errno_log ( ) const

protected

Write a line of error log after a failed system call has set the global errno to a non-zero value.

Access the current global error log stream. A line feed and a preamble, including the latest OS error, will be written to the stream.

Note! The global error stream will be "disabled" (i.e. set to a dummy stream) unless compiler macro TASKRUNNER_LOGERR is defined.

◆ flushLogFile()

static void Logger::flushLogFile ( )

inlinestatic

Anything written to the global log may be buffered for quite some time, and thus not visible in the destination file. This method will flush the buffer and write an extra empty line.

Calling this often may be bad for performance.

◆ log() [1/2]

std::ostream& Logger::log ( ) const

inlineprotected

Write a line of info log.

Access the current global info log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

Note! The global info log stream will be "disabled" (i.e. set to a dummy stream) unless compiler macro TASKRUNNER_LOGINFO is defined.

◆ log() [2/2]

static std::ostream& Logger::log ( const std::string & label )

inlinestatic

Write a line of info log.

Access the current global info log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

In non-static members of subclasses to Logger, the method Logger::warn_log() should be used instead of this function.

◆ msSince()

int64_t Logger::msSince ( const TimePoint & t )

static

Return number of milliseconds since the given TimePoint. The returned value might be negative.

◆ msTo()

int64_t Logger::msTo ( const TimePoint & t )

static

Return number of milliseconds until the given TimePoint. The returned value might be negative.

◆ secondsSince()

double Logger::secondsSince ( const TimePoint & t )

static

Return number of seconds since the given TimePoint. The returned value might be negative.

◆ secondsTo()

double Logger::secondsTo ( const TimePoint & t )

static

Return number of seconds until the given TimePoint. The returned value might be negative.

◆ setLogFile()

void Logger::setLogFile ( std::ostream & stream )

static

Set global log destination.

The given stream will be the destination of all subsequent log calls globally. You must make sure the global stream never is destroyed, at least not until Logger::setLogFile is called with another stream.

◆ setLogLimit()

void Logger::setLogLimit	(	unsigned int	loglines = `0`,
		unsigned int	warnlines = `0`,
		unsigned int	errlines = `0`
	)

static

Set max number of lines of info/warn/err log.

If 0, reset to previous (non-zero) max number of lines. After the limit has been reached, no more lines for that log level will be printed until the limit has been reset.

◆ warn_log() [1/2]

std::ostream& Logger::warn_log ( ) const

inlineprotected

Write a line of warning log.

Access the current global warning log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

Note! The global warning log stream will be "disabled" (i.e. set to a dummy stream) unless compiler macro TASKRUNNER_LOGWARN is defined.

◆ warn_log() [2/2]

static std::ostream& Logger::warn_log ( const std::string & label )

inlinestatic

Write a line of warning log.

Access the current global warning log stream. A line feed and a preamble will be written to the stream. Then send whetever you want to the log stream using the standard std::ostream API.

In non-static members of subclasses to Logger, the method Logger::warn_log() should be used instead of this function.

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

src/framework/logger.h
src/framework/logger.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ Logger()

Member Function Documentation

◆ createHashKey()

◆ dbg_log()

◆ err_log() [1/2]

◆ err_log() [2/2]

◆ errno_log()

◆ flushLogFile()

◆ log() [1/2]

◆ log() [2/2]

◆ msSince()

◆ msTo()

◆ secondsSince()

◆ secondsTo()

◆ setLogFile()

◆ setLogLimit()

◆ warn_log() [1/2]

◆ warn_log() [2/2]