LazLogger unit

Provides a logging framework for Lazarus applications.

LazLogger.pas provides logging facilities to write message to a file or stdout device. Messages can be logged plain, or enclosed in begin/end like blocks, adding indent to all messages between to points (blocks can be nested). It also has the ability to filter groups of messages.

It can read the command line and environment to find the desired filename. By default it looks for a --debug-log= argument on the command line or "appname"_debuglog in the system environment.

If no log name is found StdOut is used.

The easiest method is to use the unit and put "DebugLn"/ "DbgOut" / "DebugLnEnter"/ "DebugLnExit" in your code. This works without any further setup.

LazLogger.pas is part of the LazUtils package.

Classes and records

`TLazLoggerFile`	class	Implements a logger which uses a file or the STDOUT device as the destination for log messages.
`TLazLoggerFileHandle`	class	Represents a file or device handle for a logger class instance.
`TLazLoggerFileHandleMainThread`	class	Represents a File handle for logger operations queued in the main thread.
`TLazLoggerFileHandleThreadSave`	class	Performs file operations using a critical section.

Procedures and functions

`assign(Boolean):TLazLoggerLogEnabled`	operator	Implements the Assign (':=') operator using a Boolean argument for the TLazLoggerLogEnabled type.
`assign(PLazLoggerLogGroup):TLazLoggerLogEnabled`	operator	Implements the Assign (':=') operator using a Pointer to a logger group for the TLazLoggerLogEnabled type.
`dbghex`	function	Generates a message with the hexadecimal representation for the specified numeric value.
`dbgMemRange`	function	Generates a message with the hexadecimal-encoded content for the specified block of memory and size.
`dbgMemStream`	function	Generates a message with the hexadecimal-encoded values from the specified memory stream.
`dbgObjMem`	function	Generates a message with the hexadecimal-encoded memory content for the specified object instance.
`DbgOut`	procedure	Writes a message to the log.
`DbgS`	function	Generates a debugger message formatted with the value(s) for the specified type(s).
`DbgSJoin`	function	Generates a debugger message with the combined values of the specified arguments.
`DbgSName`	function	Generates a message with the optional name and class type for the specified object.
`DbgSTime`	function	Generates a message with the tick count for the computer system.
`DbgStr`	function	Generates a debugger message with the content from the specified value.
`DbgWideStr`	function	Generates a debugger message with the specified WideString content.
`DebugLn`	procedure	Writes a message to the log.
`DebugLnEnter`	procedure	Writes a message to the log.
`DebugLnExit`	procedure	Writes a message to the log.
`DebuglnStack`	procedure	Writes a message to the log.
`DumpExceptionBackTrace`	procedure	Write the stack trace back when an exception is detected.
`GetDebugLogger`	function	Gets the value for the DebugLogger property.
`logicaland(TLazLoggerLogEnabled,TLazLoggerLogEnabled):TLazLoggerLogEnabled`	operator	Implements the logical And operator for TLazLoggerLogEnabled types.
`logicalor(TLazLoggerLogEnabled,TLazLoggerLogEnabled):TLazLoggerLogEnabled`	operator	Implements the logical Or operator for TLazLoggerLogEnabled types.
`SetDebugLogger`	procedure	Sets the value for the DebugLogger property.

Types

`DebugLogger`	property	Contains the class instance for the file-based logger.
`PLazLoggerLogGroup`	type	Alias for the PLazLoggerLogGroup type in the LazLoggerBase unit.
`TLazLoggerWriteExEventInfo`	type	Alias for the TLazLoggerWriteExEventInfo type in lazloggerbase.pas.

Uses

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.