From:	y0000980 AT ws DOT rz DOT tu-bs DOT de (Andree Borrmann)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Buggy Symlinks (Bug in Stub.asm)
Date:	20 May 1997 10:35:04 GMT
Organization:	Technische Universitaet Braunschweig, Germany
Lines:	44
Distribution:	world
Message-ID:	<5lruoo$fs$1@ra.ibr.cs.tu-bs.de>
NNTP-Posting-Host:	rzab5.rz.tu-bs.de
Keywords:	symlink DJGPP stub bug
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Hi!

I wonder if I am the first one who found this serious bug inside the stub:

Symlinks which filename without extension is 8 chars long fail (most times),
here is why:

; (stub.asm)
;-----------------------------------------------------------------------------
;  Replace the stub's file name with the link's name after the directory

	mov	cx, 8			; max length of basename
	mov	di, stubinfo_basename	; pointer to new basename
@b1:
	mov	al, [di]		; get next character
	inc	di
	or	al, al			; end of basename?
	je	@f1
	mov	[bx], al		; store character
	inc	bx
	loop	@b1			; eight characters?
@f1:
	movd	[bx+0], 0x4558452e	; append ".EXE"
	add	bx, 4
        mov     [bx], al                ; al = 0

!!! al is NOT 0 if basename was 8 chars... !!!

        movb    [bx], 0                 ; this is better !!!

IMHO their are too many assumptions like this one in "stub.asm"...
may be a bit to much "size-optimization"...

(BTW: in PMSTUB.ASM from pmodedj it's:
        mov     [byte ptr bx], 0
 interesting, he?)

Another question for me is why it sometimes work, eg. if I've started iview first...

Bye,
Andree

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