Path: utzoo!attcan!uunet!zephyr.ens.tek.com!tekcrl!tekgvs!toma
From: toma@tekgvs.LABS.TEK.COM (Tom Almy)
Newsgroups: comp.lang.lisp.x
Subject: Re: XLISP SAVE/RESTORE ???
Message-ID: <6958@tekgvs.LABS.TEK.COM>
Date: 27 Feb 90 17:54:01 GMT
References: <1973.25ea7b8e@cc.helsinki.fi>
Reply-To: toma@tekgvs.LABS.TEK.COM (Tom Almy)
Organization: Tektronix, Inc., Beaverton,  OR.
Lines: 57

In article <1973.25ea7b8e@cc.helsinki.fi> stickler@cc.helsinki.fi writes:
>Is there a fix for XLISP 2.x SAVE()/RESTORE() ?
>My PC version (downloaded from BIX) saves without error, but
>complains when restoring.

There are three separate problems that affect version 2.0 and 2.1. 
(There are dozens of other bugs as well -- I mail out bugfixed sources
upon receipt of a disk and stamped mailer)

*******************
Problem: "restore" corrupts system.
Diagnosis: argument stack not being reset -- initial garbage collect
 "marks" random memory!

Solution: Add to "initialize" in xlirestore:


	xlfp = xlsp = xlargstkbase;
	*xlsp++ = NIL;

*******************
Problem: "restore" corrupts system with 8086 compilers.
Diagnosis: cvoptr is doing improper arithmetic.

Solution: CVPTR in xlisp.h needs to be defined as 
#define CVPTR(x)	((((unsigned long)(x) >> 16) << 4) + ((unsigned) x))
	return statement in cvoptr() (xlimage.c) needs to be changed from:
return (off + (OFFTYPE)((p - seg->sg_nodes) << 1));
	to:
return (off+(((CVPTR(p)-CVPTR(seg->sg_nodes))/sizeof(struct node))<<1));


Note: for this to work with non-8086 compilers, the default for CVPTR
should be changed from (x) to ((OFFTYPE)(x)).

****************

BUG: Any attempt to do more than one RESTORE in a session causes the error
	"insufficient memory - segment".

SOLUTION:
In file xlimage.c, function freeimage(), change

		if (((fp = getfile(p)) != 0) && (fp != stdin && fp != stdout))

to:

		if (((fp = getfile(p)) != 0) && 
			 (fp != stdin && fp != stdout && fp != stderr))



=============================

Tom Almy
toma@tekgvs.labs.tek.com
Standard Disclaimers Apply