So like all zork obsessed people (I really should get help or something), I was trying to build a z-machine interpreter for the x68000, using Lydux’sÂ cross GCC compiler. Â And it was honestly looking like a LOT of work in the IO department. Â Thinking that the older versions were more simpler, I went looking for the oldest open Z-machine,Â called the “The InfoTaskForce Infocom interpreter”, released by theÂ InfoTaskForce. Â Unfortunately I can only find version 4.01 searching for the source code. Â Which still looks too complicated. Â But looking the history file, the project started back in 1987. Â So with that to go on a new google search got me this:
From an TRS-80 dump of all things. Â I don’t know what version this is other than the brief copyright mention:
/* (C)opyright 1987 InfoTaskforce. */
All of the files are dated 4/12/2001 so they obviously aren’t original.Â And the version string is:
echo ( “Interpreter: C Version 1.0\n” ) ;
So assuming this is correct, from the 4.01 history file:
REV_E – June 25, 1987.
REV_E is the first major overhaul to the interpreter.
* The source is now significantly lint free.
* TERMCAP support has now been added [#define TERMCAP option].
* Screen paging and word wrap has been added, along with a new
command line option which disables screen paging (-p).
* Random number generator seeding using time () added [#define
* Attributes in the object list are listed as bits.
* A debuging version can now be produced as an inbuilt options
[#define DEBUG option].
* The coded requirement that 25k is always free in the system can
now be removed [#define ALLOCALL option].
* A new command line option was added to print the object/room list
as a tree (-r).
* interp.c has been re-written to improve efficiency [large
switches have been replaced with arrays of pointers to funcions].
There are now 14 machines on the porting list:
Machine C Compiler Operational Porting details
Macintosh Aztec C Version 1.06F 18/05/87
Macintosh Lightspeed C 2.01 29/05/87 Use “rb” & “wb” in all fopen()s
IBM PC/AT Microsoft C 4 30/05/87 Link with binmode.obj
DEC VAX 11/780 UNIX V7 cc 01/06/87
HP-9000 HP-UX cc 02/06/87
gould cc 03/06/87
Amiga Aztec C 04/06/87
Pyramid 9810 cc 04/06/87
Pyramid 90x cc 04/06/87
Osiris cc 05/06/87
DEC PDP-11/? UNIX V? cc 07/06/87 EXTENSIVE
mods to fix problems with signed chars.
VAX VMS cc 16/06/87 Add #define
times ttmes to fix multiply defined symbol problem. [infocom.h]
Version 1.00 – August 17, 1987.
The REV_C interpreter of June 2, 1987 was officially archived as
Version 1.00 on August 17, 1987.
So this means it’s very 16bit & 32bit friendly, especially on BIG endian machines like the 68000 processor.
Luckily this older version is pretty trivial to compile, and get running. Â But I was over thinking the build process and decided to strip the executable as GCC would kick out a 500kb file, which objcopy would extract a 81kb executable. Â Stripping it brought the size down to a 50kb executable but it wouldn’t run in either xm6 or run68. Â I ended up going in circles for a while trying to find fault in what is broken where until I manually compiled the interpreter, and omitted the strip step and suddenly had a working interpreter.
Now there is one issue, saving doesn’t work. Â Something in the libc is having issues using fopen with a file to write. Â Reading works perfectly fine though. Â So to fix it, I went ahead and redid the save feature to use the HumanOS native _open/_write/_close functions and I’m able to now save & restore a game.
D:\proj\run68\test>run68.exe infocom.X minizork.z3
MINI-ZORK I: The Great Underground Empire
Copyright (c) 1988 Infocom, Inc. All rights reserved.
ZORK is a registered trademark of Infocom, Inc.
Release 34 / Serial number 871124
West of House
You are standing in an open field west of a white house, with a boarded front
door. You could circle the house to the north or south.
There is a small mailbox here.
West of House Score: 0/0
Living Room Score: 10/19
A nasty knife
A brass lantern (providing light)
A brown sack
A glass bottle
The glass bottle contains:
A quantity of water
Living Room Score: 10/20
In this process I’ve also managed to build run68, and verified that it’s operating correctly, as both run68 and XM6 both failed to write to a file with fopen, and both work using the native calls.
I’m sure most people won’t care but I think it’s great having the ability to run a GCC generated C program in a relatively small interpreter.
If anyone cares, here is my updated cross compiler + run68 source along with tweaked Info Task Force 1.0 source. Â Or a disk image that XM6 can boot up, and run some demo programs from Infocom of ages ago.