[AD] Config routines bug (2)

["Eric Botcazou" <ebotcazou@xxxxxxxxxx>]

I've tried to build a little rationale on the topic:

1. The behaviour that should have been implemented (as exposed in the docs)
is unsatisfactory: what if two sections contain the same entry ? Why picking
the first one and not the last one ? So passing NULL shouldn't mean
searching the entire file.

2. Users may want to store only few datas in config files, without
specifying any section. So we should have a mechanism to have access to
'sectionless' datas, and using NULL seems to be the most natural one.

3. Using an end-of-section marker would overload config files, so
'sectionless' datas should be put at the beginning of the files.

4. Using the NULL section for Allegro settings would be dangerous: simply
adding a section before them in the config files would break them. So we
should encapsulate every Allegro setting into a section.

The only remaining question would then be: how many sections ?
Currently, there are already: [fb_mode_XxY], [sound], [grabber], [joystick].
I'd propose to add: [system], [graphics], [keyboard], [mouse] and [timer].

Comments ?

--
Eric Botcazou
ebotcazou@xxxxxxxxxx