LZX archive support

MiDWaN · April 22, 2018, 1:19pm

I'd really love to see LZX archive support in Opus.
I understand that you're currently re-using code from 7-zip, which doesn't officially support LZX. However, I found that they do have an LZXDecoder in the source files.

Check the CPP\7zip\Compress folder of the 7-zip sources archive, and you'll find:

Lzx.h
LzxDecoder.cpp
LzxDecoder.h

I'm not sure why 7-zip doesn't seem to use that on the front-end, or indeed open LZX archives, but perhaps the code can be re-used to implement LZX support in Opus anyway?

If that doesn't help for some reason, I can offer an alternative also: I'm using this piece of code to support LZX archives in Amiberry, an Amiga emulator for ARM devices:

github.com

midwan/amiberry/blob/master/src/archivers/lzx/unlzx.cpp

/* $VER: unlzx.c 1.0 (22.2.98) */
/* Created: 11.2.98 */
/* Added Pipe support to read from stdin (03.4.01, Erik Meusel)           */

/* LZX Extract in (supposedly) portable C.                                */

/* ********************* WINDOWS PORTING NOTES STARTS *********************/

/* Ported to Windows Platform by Stefano Coletta on 22.5.02               */
/* creator@mindcreations.com or visit http://creator.mindcreations.com    */

/* Changes to original code include:                                      */
/* - Using #include <direct.h> to substitute the mkdir() function call    */
/* - Added #include "getopt.h" to support getopt() function               */

/* Compile with:                                                          */
/* Microsoft Visual Studio 6.0 SP5 using supplied project file            */

/* ********************** WINDOWS PORTING NOTES END ***********************/

This file has been truncated. show original

I could try to implement it in Opus myself, but since I haven't written anything for Opus before, it will take me some time to understand how plugins work. I was hoping that the information above would be enough to get it officially added, but if all else fails, I'll have to take the time to develop it myself...

Leo · April 22, 2018, 1:54pm

LZX seems to be in 7-Zip to handle CAB archives. I don't know if that code is compatible with LZX/LHA archives from the Amiga or not.

If there was LZX/LHA code that provided an API similar to UnRAR.dll (or to 7z.dll, but that's more complex), we could probably integrate that.

MiDWaN · April 22, 2018, 4:33pm

How about the sources from http://aminet.net/package/util/arc/UnLZX2

They contain a Windows binary as well...

MiDWaN · April 22, 2018, 6:46pm

One more potentially helpful source:
https://totalcmd.net/plugring/UnLZX.html

It also includes sources for their UnLZX plugin for Total Commander