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structure with arbitrary-size members
Is it possible in FASM to make a subj?
I mean a structure which contains a member with size depending on the value of the other member.
Posted on 2002-10-16 12:44:16 by longer
structure with arbitrary-size members
Hi longer,

do you mean something like: 


struc SUBJ{

	.first      dd ?

	.second dd ?

                .third     dd ?



}	

virtual at 0

	subj SUBJ

	firstSUBJ = subj.first + 10

end virtual
Posted on 2002-10-18 12:10:05 by slop
structure with arbitrary-size members
Hi, sloppy!
Sorry, I can't understand what does the virtual piece of code do. :( Can you explain?
Here's what I exactly want: 


struc   RECT

{       .left           dd ?

        .top            dd ?

        .right          dd ?

        .bottom         dd ?    }



struc   RGNDATAHEADER

{       .dwSize         dd ?

        .iType          dd ?

        .nCount         dd ?

        .nRgnSize       dd ?

        .rcBound        RECT    }



struc   RGNDATA

{       .rdh            RGNDATAHEADER

        .Buffer         ???     }


The problem is that RGNDATA.Buffer seems to contain nCount RECTs.
So the question is: Can I declare RGNDATA structure in FASM?
Posted on 2002-10-19 05:43:13 by longer
structure with arbitrary-size members
Try something like the following;
struc   RECT

{       .left           dd ?

        .top            dd ?

        .right          dd ?

        .bottom         dd ?   

        .size = $    }



struc   RGNDATAHEADER

{       .dwSize         dd ?

        .iType          dd ?

        .nCount         dd ?

        .nRgnSize       dd ?

        .rcBound        RECT    

        .size = $    }



struc   RGNDATA

{       .rdh            RGNDATAHEADER

        .Buffer        = $    }



virtual at 0

	RECT RECT

end virtual



virtual at 0

	RGNDATAHEADER RGNDATAHEADER

end virtual



virtual at 0

	RGNDATA RGNDATA

end virtual

Then to access lets say the 6th RECT in the RGNDATA struc use 
;eax points to a RGNDATA struc

lea eax,[eax+RGNDATA.Buffer+RECT.size*5]

;eax points to the 6th RECT

See this thread for more info.
Posted on 2002-10-19 06:40:47 by Eóin
structure with arbitrary-size members
Thanks for your replies,
it seems I've got the idea. :alright:
Posted on 2002-10-19 12:26:02 by longer