Date: Wed, 9 Aug 95 21:39 MDT
From: mat AT ardi DOT com (Mat Hostetter)
To: sandmann AT clio DOT rice DOT edu
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: Idea: compressed COFF
Newsgroups: comp.os.msdos.djgpp
References: <DCzGM6 DOT 7zz AT cyf-kr DOT edu DOT pl> <30275b50 DOT sandmann AT clio DOT rice DOT edu>

>>>>> "Charles" == Charles Sandmann <sandmann AT clio DOT rice DOT edu> writes:

    >> So I have an idea: to create alternate versions of stub and
    >> coff2exe/stubify that would compress the COFF while creating an
    >> EXE file and decompress it while loading. The stub would be a
    >> bit bigger (decompression routine) but COFF (and resulting EXE)
    >> much smaller...

    Charles> It was suggested to use the compression routines out of
    Charles> gzip, and then code the decompression algorithm in djasm
    Charles> for inclusion in the stub.

    Charles> It's an idea looking for volunteers :-)

Interestingly, gzip is GPL'd, but "inflate.c" in the gzip distribution
is prefaced with:

/* inflate.c -- Not copyrighted 1992 by Mark Adler
   version c10p1, 10 January 1993 */

/* You can do whatever you like with this source file, though I would
   prefer that if you modify it and redistribute it that you include
   comments to that effect with your name and the date.  Thank you.
   [The history has been moved to the file ChangeLog.]
 */


Rewriting this code in djasm would be tough.  It would be nice to be
able to link this C code into the executable (uncompressed of course),
and let it uncompress the rest of the binary from protected mode.

Alternately we could use a simpler and faster (and of course less
space-efficient) compression/decompression algorithm.  There's
something to be said for simplicity and fast decompression.

-Mat