! here's the code that redefines pcre_malloc and pcre_free to
! use byte-arrays. this code is tested to work. I was in a
! brute-force trial-and-error frenzy trying all combinations
! of the alien functions to make this work, and couldn't.
! the suggestions I was offered at the irc channel also
! wouldn't work. so I got more rational and started thinking
! about how all the alien functions can work together.
! the result is a bit more repetitive than what I'd like to
! write to make this work, but it works and most importantly
! it makes perfect sense in my head and that of anyone who
! reads the docs for CALLBACK: C-GLOBAL: alien-callback and
! alien-indirect . No example in the docs mention this
! construct and I could not find an existing library that
! does this. maybe this is a first!

CALLBACK: void* pcre_malloc_t ( size_t size ) ;
C-GLOBAL: pcre_malloc_t pcre_malloc
: setup-pcre_malloc ( -- )
    void* { size_t } cdecl [ <byte-array> ] alien-callback set-pcre_malloc ;
setup-pcre_malloc ! set it up once
: pcre-malloc ( size -- ptr )
    pcre_malloc void* { size_t } cdecl alien-indirect ;

CALLBACK: void pcre_free_t ( void* ptr ) ;
C-GLOBAL: pcre_free_t pcre_free
: setup-pcre_free ( -- )
    void { void* } cdecl [ drop ] alien-callback set-pcre_free ;
setup-pcre_free ! set it up once
: pcre-free ( ptr -- )
    pcre_free void { void* } cdecl alien-indirect ;


! There are two ways to implicitly check that this is works.
! one is that calling (free) on what is returned from
! pcre-malloc crashes Factor in the same way that
! B{ 0 0 0 } (free) crashes it.
! the other way to verify it is by looking at the address
! of the returned alien. The code in the previous
! annotation always returns an alien like this:
! ALIEN: 7fdd8b0c80c0
! while this code returns an alien like this:
! ALIEN: 110b1b570
! which to me seem like two very different address spaces,
! and the latter I suspect is Factor's address space,
! although I couldn't get >c-ptr to work in order to verify
! this.
! this should be included in the docs somehow, as it took me
! a while to figure out and no-one in the IRC channel knew
! exactly how to go about it.