Overview
~~~~~~~~
libdiagnose is a simple debugging, logging and error-reporting                  
library for C/C++ with support for regular expressions and a callback           
functionality.

This library aims to provide a flexible, easy to use and filter program         
status reporting solution for C/C++ developers.  It was originally              
written for fast diagnostics of program errors.  It developed over              
time into a complete program status reporting library with a callback           
functionality and support for regular expressions.                              
                                                                                
The library supports 4 types of messages: log, debug, warning and               
error messages.  Every message can have several formats based on                
a user's choice (bare, normal, time, hexadump, ...).  The filtering             
functionality of the library supports several levels of verbosity               
reporting and regular expressions using the PCRE library for each               
type of the messages or all messages in general.  The filtering                 
can be masked by a program using this library directly, or from the             
environment in which the program runs.                                          
                                                                                
The intended use of this library is to make programs call the library           
API macros rather than external functions.  It is then possible to              
generate a replacement header file with empty macros by a script                
provided and make programs compile without the library.  It is                  
also possible to selectively disable/enable parts of the library                
functionality.  For instance, this might be desirable when compiling            
programs without debugging information for performance reasons.


User manual
~~~~~~~~~~~
For the time being, please refer to the source, in particular dg_test.c
and env.sh script.  When using the library, make sure you
don't call dg<FUNCTIONS> directly, but use them through DM_<MACROS>.

There are two reasons for this:

1) dg<FUNCTIONS> names are NOT guaranteed to remain unchanged 
   during the development of the library.
2) A program that uses this library can be built without it just by 
   importing a header file with empty macros.

Please see the dg.h file for the available macros.

The diagnose library environment variables
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Verbosity level masks: DG_(DIAGNOSE|LOG|DBG|WARN|ERR)
Regular expression filters: DG_(DIAGNOSE|LOG|DBG|WARN|ERR)_(FILE|FUNC)v?

DIAGNOSE affects all the other types of messages: LOG, DBG, WARN and ERR.