[Fontconfig] Discovering the font file from the font name

[Keith Packard]

Around 14 o'clock on Dec 18, Adriano Del Vigna de Almeida wrote:

> We need that into '~/.font.conf' there is a new tag for the
> enabled/disabled fonts, so when an client application to fontconfig
> queries fontconfig for the available fonts, those tagged as disabled are
> hidden from the applicatin request. So the user can make a complete
> customization for his needs, hidding from his applications the fonts
> that he doesn't need (or want) to use.

2.2.92 has some infrastructure for that already in the <selectfont>
element.  That contains <acceptfont> and <rejectfont> elements.  Right now,
the only thing you can stick inside of those is <glob> elements which 
match file names with shell-style globbing.  I envision adding 
pattern-based elements, perhaps using the existing <test> elements in some 
fashion.

You'll need to whack fcxml.c to add new elements, extend the FcConfig 
structure to include the necessary reject/accept data structures and then 
whack fccfg.c to store and evaluate the structures, then whack fccache.c 
and fcdir.c where it currently calls FcConfigAcceptFilename to call into 
that new evaluation code.

-keith