From: WHS <wouters@cistron.nl>
  To  : ggi-develop@eskimo.com
  Date: Sat, 05 Sep 1998 13:18:18 +0200

Re: Improved debugging system for libggi

Marcus Sundberg wrote:
> 
> Andrew Apted wrote:
> >
> > WHS writes:
> >
> > >  Isn't it much nicer to use debug prefixes (inxfixes, postfixes) like I
> > >  use in gsi, e.g. use GGI_DEBUG_CORE = n to give level n output of the
> > >  core section, GGI_DEBUG_EVENTS=0 switches off event  messages.
> >
> > That sounds better to me.
> >
> > >  going to be a nightmare trying to remember which bit was assigned to
> > >  what part of libggi.
> 
> Well, this scheme was designed to make debugging faster for people
> that know what they're doing. Mere mortals just set GGI_DEBUG to
> 255 and post th eoutput to the list.

I know what I'm doing and I know this is a kludgy system, nothing to do
with knowing/not knowing.
As I said, you're never going to remember those bits and having to add
bits to get output is a nuisance at the very least.

> If you want more different debuglevels I won't object to it, but
> please keep the ability to turn on full debugging for different
> sections with a mask.

I'm not going to change libggi, at least until gsi 0.7 is ready, but as
you're doing these debug changes you should consider doing it. It's
really a lot easier. I've attached debug.h I use at the moment.

Regards,

Wouter

/* Debug definitions
 * 
 * By W.H.Scholten 1996,1997,1998
 *
 * This file is public domain
 */

//Inspector Gadget is ALWAYS on duty

/*---------------------------------------------------------------------------*
 *	use the environment variable DEBUG_LEVEL to set the level of
information
 *	you want to see (unset or 0 gives no output)
 *	i.e. DEBUG_LEVEL=1, export DEBUG_LEVEL for bash
 *	Hardcoding a debug level to 11,12,13 will always give level 1,2,3
output
 *	DEBUG_PREFIX can be set before the #include <gsi/debug.h> in any file
to
 *	control output of different program sections with different
environment
 *	variables.

*---------------------------------------------------------------------------*/

#ifndef _WHS_DEBUG_H
#define _WHS_DEBUG_H

#undef DEB
#undef DEB1
#undef DEB2
#undef DEB3
#undef ASSERT

#ifdef DEBUG
#include <stdlib.h>
#  ifndef DEBUG_LEVEL
#    define DEBUG_LEVEL 1
#  endif
#  ifndef DEBUG_PREFIX
#    define DEBUG_PREFIX ""
#  endif
static int _whs_debug(int level) {
	static int whs_dbl=-1;
	if (whs_dbl<0) {
		char *whs_env;

		whs_env = getenv("DEBUG_LEVEL");
		if (whs_env !=NULL) whs_dbl=atol(whs_env);
		else whs_dbl=0;

		whs_env = getenv(DEBUG_PREFIX"DEBUG_LEVEL");
		if (whs_env !=NULL) {
			int whs_prefix_dbl = atol(whs_env);
			if (whs_prefix_dbl > whs_dbl) whs_dbl = whs_prefix_dbl;
		}
	}
	return (whs_dbl>=level);
}
#  define DEB(x) x
#  define DEB1(x) { if (_whs_debug(1) ) { x; } }
#  define DEB2(x) { if (_whs_debug(2) ) { x; } }
#  define DEB3(x) { if (_whs_debug(3) ) { x; } }

#  define prt printf
#  define fprt fprintf
#  define ASSERT(expr) { if (!(expr)) { fprintf(stderr, "Assertion
failed: %s, file %s, line %d\n", #expr, __FILE__, __LINE__); exit (0); }
}
#  define ENSURE(expr) ASSERT(expr)

#else
#  define DEB(x)
#  define DEB1(x)
#  define DEB2(x)
#  define DEB3(x)
#  define ASSERT(expr)
#  define ENSURE(expr)

#endif


//Show me the way, o glorious inspector.
#endif /* _WHS_DEBUG_H */