Issue with KWAJ method 2 decompression
jsummers opened this issue · 2 comments
Using the contents of this file: MOUSE901.ZIP ...
Use msexpand to decompress MOUSE.IN$. Expected results: A readable text file. Actual results: a garbled file.
The problem exists for all KWAJ#2 files that I've tested. Note that the EXPAND.EXE DOS utility from MOUSE901.ZIP can successfully decompress the file.
What I think is that KWAJ#2 is supposed to use the mode that libmspack calls LZSS_MODE_QBASIC, instead of LZSS_MODE_EXPAND.
Or maybe there is a different kind of KWAJ#2 file out there that libmspack correctly decompresses. If so, I'd like to know about it.
Some other places to find KWAJ#2 files: lifepl02.zip, PRO207/
Thanks for finding this, I agree completely. Looking at the test suite for KWAJ decoding, I found I don't have any files using method 2, only 3 and 4.... even though I have archives containing such files.
To check it's not just that expand.exe, I unpacked all the test files I had (and now some method 2 files) with these executables which can unpack KWAJ files (their size/checksum comes after decrunching them, if they were PKLITE compressed).
The one in MOUSE901.ZIP is decomp.exe 1.00
| File | First line of help output | Size | SHA256 |
|---|---|---|---|
| decomp.exe | Microsoft (R) Char-Setup Toolkit Decompression Utility - Version 1.00 | 18684 | 3e8762a9df84c365a61b4270072a03e6d64f2da46dc9991095abe61c3a494156 |
| decomp.exe | Microsoft (R) Char-Setup Toolkit Decompression Utility - Version 1.02 | 35921 | 7b7dde3bc19d4ffe7b7d166e718daa063c9879ce9f4006543a97840a24d1bf01 |
| decomp.exe | Microsoft (R) Decompression Utility - Version 1.4 | 39044 | 0d2de164d6e9173d9230498721e624450aef25dd9b667c622509670e9bd835c6 |
| expand.exe | Expands one or more compressed files. | 26097 | 5e0e909dabb4b9042bff6e9b2d103ccca5dccfcf71b4938727ecfe9bfa7fc42c |
| expand.exe | Microsoft (R) File Expansion Utility Version 2.10 | 25239 | 668d6302c4042f5fa9a25c1e5a953a64904ed878ecbd8d93509a62cef930e436 |
| expand.exe | Microsoft (R) File Expansion Utility Version 2.10 | 24887 | bbd30fbcc98d121e2ca0d4cdb2ad4570b0d076132b842da58631e69a5e2a308c |
I unpacked all the files I have with all these programs, and for the methods they support, they all unpack files with exactly the same results. So I'm in agreement that method 2 is the QBasic variant of SZDD. Thanks for investigating.