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:: rtl ::

class Logfile

Base Classes
Known Derived Classes

virtual abstract interface template
The intended use for class Logfile is to write time stamp information for profiling purposes. Profiling output should only be generated for a special product version of OpenOffice which is compiled with a defined preprocessor symbol 'TIMELOG'. Therefore we have provided a set of macros that uses the class Logfile only if this symbol is defined. If the macros are not sufficient, i.e. you need more then three arguments for a printf style message, then you have to insert an #ifdef TIMELOG/#endif brace yourself. Additionally the environment variable RTL_LOGFILE has to be defined in order to generate logging information. If the variable is not empty, it creates a file with the name $(RTL_LOGFILE)_$(PID).log, where $(PID) is the process id of the running process. It can be used as a run time switch for enabling or disabling the logging. Note that this variable is evaluated only once at the first attempt to write a message. The class LogFile collects runtime data within its constructor and destructor. It can be used for timing whole functions. If you want to write timing data without context you can use the RTL_LOGFILE_TRACE-macros which are defined inside . The class LogFile should not be used directly, instead use the RTL_LOGFILE_CONTEXT/ RTL_LOGFILE_TRACE-macros. Macro usage: ------------ RTL_LOGFILE_CONTEXT( instance, name ); This macro creates an instance of class LogFile with the name "instance" and writes the current time, thread id and "name" to the log file. Example: RTL_LOGFILE_CONTEXT( aLog, "Timing for foo-method" ); RTL_LOGFILE_CONTEXT_TRACE( instance, mesage ); RTL_LOGFILE_CONTEXT_TRACEn( instance, frmt, arg1, .., arg3 ); These macros can be used to log information in a "instance" context. The "instance" object is used to log message informations. All macros with "frmt" uses printf notation to log timing infos. Example: RTL_LOGFILE_CONTEXT_TRACE( aLog, "Now we call an expensive function" ); RTL_LOGFIlE_CONTEXT_TRACE1( aLog, "Config entries read: %u", (unsigned short)i ); RTL_LOGFILE_TRACE( string ); RTL_LOGFILE_TRACEn( frmt, arg1, .., arg3 ); These macros can be used to log information outside a context. The macro directly calls rtl_logfile_trace to write the info to the log file. All macros with "frmt" uses printf notation to log timing infos. Example: RTL_LOGFILE_TRACE( "Timing for loading a file" ); RTL_LOGFILE_TRACE1( aLog, "Timing for loading file: %s", aFileName ); The lines written to the log file consist of the following space separated elements: 1. The time relative to the start of the global timer in milliseconds. The times is started typically for the first logged line. 2. Thread id. It's absolut value is probably of less interest than providing a way to distinguish different threads. 3. a. An opening or closing curly brace indicating the start or end of a scope. 4a. Function name or general scope identifier. b. A vertical line indicating an arbitrary message. 4b optional function name or general scope identifier. 5b A colon followed by a space and a free form message terminated by a newline. There is a second version of creating a context. RTL_LOGFILE_CONTEXT_AUTHOR takes two more arguments, the name of the project and the author's sign who is responsible for the code in which the macro is used.

Public Members


Logfile( const sal_Char * name );

Logfile( const sal_Char * project, const sal_Char * author, const sal_Char * name );

~Logfile( );
const sal_Char *
getName( );

Private Members


::rtl::OString m_sName;

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