Broken for Quake 1 on amd64 and arm64

[grepwood]

I have the Quake 1.06 CD and wanted to extract the gamedata from it on arm64 in order to make the case that games-fps/quake1-data package in Gentoo can receive an arm64 keyword, making the installation of this package less of a hack on this CPU architecture.

The extraction failed and I've started looking into when and how it failed. If we mount the CD into /mnt/cdrom, we can do lha l /mnt/cdrom/resource.1 to try and receive the file list in the archive, however, it fails:

PERMISSION  UID  GID      SIZE  RATIO     STAMP           NAME
---------- ----------- ------- ------ ------------ --------------------
LHa: Error: Checksum error (LHarc file?)
---------- ----------- ------- ------ ------------ --------------------
 Total         0 files       0 ****** Nov  5  1996

As a matter of curiosity I've repeated the procedure on amd64 and got the same result.

This issue is reproducible with these commits:

• 7c3cd95
• 2695022
• 4f193b1

[grepwood]

I found out why this happens. The filename is resource.1 - meanwhile lha expects MS-DOS SFXs to have .exe extensions. Renaming the file fixes the issue, but that still means lha is unable to determine the file type based on internal file signatures.