Class LogStream

Inheritance Relationships

Base Type

Class Documentation

class LogStream : public ecl::TextStream<SharedFile>

A customised textstream for fast, multithreaded logging to file.

Together with the LOG and FLUSH macros, this class enables fast, multithreaded logging with multiple modes, customisable headers and timestamps.

Usage:

Multiple modes are most conveniently utilsed via customised enums. For example:

enum LogModes {
   Warning,
   Error,
   Debug,
};

Note that this is an advantage over alot of other loggers in that it gives you the freedom to define your own error logging levels. Each mode can then be associated inside the log stream with its own customised header.

LogStream log_stream("test.log")
log_stream.enableMode(Warning,"WARNING");
log_stream.enableMode(Error,"ERROR");
log_stream.enableMode(Debug,"DEBUG");

This process can be repeated from multiple threads each with its own instance of the log stream attached to the single file. Using the log stream is then done via the macros LOG and FLUSH

LOG(log_stream, Warning) << "This is a log message from main().\n";
FLUSH(log_stream)

By default this will automatically add header and timestamp information. You can manually disable these if you prefer.

Public Functions

inline LogStream()

Default constructor, underlying device must be manually opened.

This must open the underlying shared file device manually via device().open() as you would do if using a TextStream.

inline LogStream(const std::string &file_name, const WriteMode &mode = New)

Convenience constructor for logstreams.

This constructor enables RAII style construction of the underlying shared file device.

Parameters:

  • file_name – : output file name.

  • mode – : mode for writing (New, Append).

Throws:

StandardException – : throws if the connection failed to open.

inline virtual ~LogStream()
void enableHeader()

Enable header information.

This prints the header at the beginning of any logging message. The header is a string that is specified when calling the enableMode() function.

void disableHeader()

Disables header information.

This turns off printing of the header at the beginning of any logging message.

void enableTimeStamp()

Enable time stamps.

This prints a timestamp at the beginning of any logging message. The timestamp is in the format seconds.nanoseconds (think unix time).

void disableTimeStamp()

Disable time stamps.

This disables timestamps at the beginning of any logging message. The timestamp is in the format seconds.nanoseconds (think unix time).

void enableMode(int mode, const std::string header = "")

Enable the given mode and associate the specified header.

Enable the given log mode and associate it with the specified header string.

Parameters:

  • mode – : the log mode.

  • header – : the string to precede the log message if required.

void disableMode(int mode)

Disable the given log mode.

Disable the given log mode.

Parameters:

mode – : the log mode.

bool isEnabled()

Check to see if any modes are enabled.

Check to see if any modes are enabled.

Returns:

bool : true if any modes are enabled, false otherwise.

bool isModeEnabled(int mode)

Check to see if a particular mode is enabled.

Check to see if the specified mode is enabled.

Returns:

bool : true if the modes is enabled, false otherwise.

LogStream &log(int mode)

Log streaming function.

Do not use this directly, rather it is indirectly utilised by the LOG macro, which should only reach here once isModeEnabled() is checked. It adds a header and timestamp if it is configured to do so and then passes the stream to the program for further additions.

Parameters:

mode – : log mode that is being logged.

Returns:

OutputTextStream : log stream’s output streaming parent.