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Title: Structure problem
Post by: RuiLoureiro on May 26, 2011, 08:25:46 PM

I have the following struct

MODE struct
pAAA dd ?
pBBB dd ?
kData db 256 dup (?)
pCCC dd ?
MODE ends

and the buffer is defined as:

LENX equ sizeof MODE
Buffer db LENX*1000 dup (?)

If ESI points to the Buffer somewhere
how do i get the entry point to kData (in ESI or in EDI,...)

Its all, thank you

Title: Re: Structure problem
Post by: jj2007 on May 26, 2011, 08:35:47 PM

Code Select

	mov eax, 123	; member #123
	imul eax, eax, LENX
	add eax, offset Buffer
	mov [eax.MODE.kData], 123

Title: Re: Structure problem
Post by: qWord on May 26, 2011, 08:37:34 PM

Code Select

lea edi,Buffer[N*SIZEOF MODE]    ; edi points to some element (MODE) in array
mov [edi].MODE.kData[0],1        ; set first byte of kData
lea esi,[edi].MODE.kData[0]      ; esi = pointer to first byte

Title: Re: Structure problem
Post by: jj2007 on May 26, 2011, 08:44:12 PM

... provided that N is an immediate - an unlikely case for an array with 1,000 members :wink

Title: Re: Structure problem
Post by: mineiro on May 27, 2011, 03:34:42 AM

Code Select


mov eax,"seno"
lea	esi, Buffer
assume esi:ptr MODE
lea edi, [esi].kData   ;entry point, index 0
stosd
lea	edi, [esi].kData + 1 * sizeof MODE  ;index 1
stosd
assume esi:nothing

Code Select


mov eax,"seno"
lea edi, Buffer.MODE.kData + 0 * sizeof MODE
stosd

Title: Re: Structure problem
Post by: RuiLoureiro on May 27, 2011, 01:45:58 PM

@@qWord: exactly what i want :wink

@@jj: :thumbu

@@mineiro: i assume i dont like to use ASSUME ! :green2

thanks all

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General Forums => The Campus => Topic started by: RuiLoureiro on May 26, 2011, 08:25:46 PM