[AD] Reading an allegro packed file directly from a datafile returns incorrect values

[Jay Bernardo <allegrolist@xxxxxxxxxx>]

I believe I have found an issue with the packfile routines and  
datafiles.  According to the documentation, what I'm trying to do  
should be perfectly possible. Let me explain the situation.

Version of Allegro: 4.2.0. Using PACKFILE/pack_fopen/pack_iputl I am  
writing some data to a file, packed (mode "wp"). I am then putting  
this file into a datafile with the grabber tool, as binary data. When  
I try to read this file from the datafile directly, however, the  
results I get back during reads are complete garbage. I'm reading in  
the file using PACKFILE/pack_fopen/pack_igetl with a mode of "rp"  
using the magical notation (e.g., "datafile.dat#object").

I have noticed that if I generate a file without the pack mode this  
all works perfectly fine. Either this is a bug, or reading files  
(that are packed) directly from a datafile is invalid. I'm not sure  
which. For the record, the datafile is using no compression. I have  
attached a set of test programs you can use to verify the issue.

fileMaker.c will simply generate a file named "file" that is written  
with mode "wp" and should contain the value "123" written using  
pack_iputl.
fileReader.c will open the packed file in mode "rp" and print the  
contents to the screen
datafileReader.c will open the file "datafile.dat#file" and print the  
contents to the screen

Within the tarball you'll also find the pre-existing datafile that I  
used for my own testing, as well as the original file written by  
fileReader. I suggest trying the ones I have generated as well as  
versions manually generated. If it's of any use, the junk value I get  
when attempting to read the 123 from the file is: 560491635

-Jay

Attachment: packfile.tar.gz
Description: GNU Zip compressed data