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I wrote the next source code, but when i run it doesnt work. Every time i received error 610. I read MSDN but i don't see why it doesnt work.

;-------------------------------------------------------------------------
GetDialUp PROC
MAX_ENTRIES EQU 100
LOCAL RASMemoryBuffer:DWORD
LOCAL dwEntryInfoSize:DWORD

INVOKE RasGetEntryProperties, 0, 0, 0, ADDR dwEntryInfoSize, 0, 0
m2m lpcb, dwEntryInfoSize

INVOKE GlobalAlloc,GMEM_FIXED OR GMEM_ZEROINIT,dwEntryInfoSize
.IF eax == -1
mov eax, 0
RET
.ENDIF
mov RASMemoryBuffer,eax
mov edi, RASMemoryBuffer
assume edi:PTR RASENTRYNAME
mov .dwSize, SIZEOF(RASENTRYNAME)
INVOKE RasEnumEntries, 0, 0, edi, ADDR lpcb, ADDR lpcEntries
INVOKE PrintEAX, eax
cmp eax, 0 ;eax = ERROR_BUFFER_INVALID (code 610)
je lab3190
szText Str2, "RasEnumEntries error?"
INVOKE MessageBox,NULL,ADDR Str2,ADDR AppName,MB_OK
jmp lab3208
lab3190:

...........

lab3208:
assume edi:nothing

INVOKE GlobalFree, RASMemoryBuffer
RET
GetDialUp ENDP
;-------------------------------------------------------------------------

Please help me

Posted on 2002-09-23 16:53:44 by martidim

Source code problem

Wild guess (can't try it right now):

Change
INVOKE RasEnumEntries, 0, 0, edi, ADDR lpcb, ADDR lpcEntries

to

INVOKE RasEnumEntries, 0, 0, , ADDR lpcb, ADDR lpcEntries

And better dont use EDI, because it might get changed by the API call.

Posted on 2002-09-23 17:13:08 by bazik

Source code problem

Interesting. All seems to be workable, but...

I traced inside RasEnumEntries and discovered that it expects 108h in first dword of buffer pointed by lprasentryname. It's size of RASENTRYNAME structure as it should be.
But currently RASENTRYNAME defined like this:

RAS_MaxEntryName equ 256



RASENTRYNAMEA STRUCT

    dwSize dd ?

    szEntryName db RAS_MaxEntryName + 1 dup(?)

RASENTRYNAMEA ENDS

And its size is 105h.

It's correct, IMHO, because in M$'s res.h RASENTRYNAMEA is also defined like this:

#define RAS_MaxEntryName      256



#define RASENTRYNAMEA struct tagRASENTRYNAMEA

RASENTRYNAMEA

{

    DWORD dwSize;

    CHAR  szEntryName[ RAS_MaxEntryName + 1 ];



#if (WINVER >= 0x500)

    DWORD dwFlags;

    CHAR  szPhonebookPath[MAX_PATH + 1];

#endif



};

I have currently no c compiler, but, anyway,
all this means that 3-bytes padding should be added at the end of RASENTRYNAMEA.
And actually it should be defined like this:



RASENTRYNAMEA STRUCT

    dwSize dd ?

    szEntryName db RAS_MaxEntryName + 1 dup(?)

    [color=red]db 3 dup(?)[/color]	; add this line

RASENTRYNAMEA ENDS

That was first problem.
The next one. RasEnumEntries wants buffer which size is larger than RasGetEntryProperties returns.
So first time you call RasEnumEntries, it returns ERROR_BUFFER_TOO_SMALL and sets cb to the number of bytes required. So, you have to realloc more memory and call it again.
Below is workable ex:

.386

.model flat, stdcall

option casemap:none



include \masm32\include\windows.inc

include \masm32\include\user32.inc

include \masm32\include\kernel32.inc

include \masm32\include\rasapi32.inc



includelib \masm32\lib\user32.lib

includelib \masm32\lib\kernel32.lib

includelib \masm32\lib\rasapi32.lib



.data

Str2		db "RasEnumEntries error?", 0

cb		UINT	0

cEntries	UINT	0

szEmpty		db 0

.code



GetDialUp proc uses edi

MAX_ENTRIES EQU 100 

LOCAL RASMemoryBuffer:DWORD

LOCAL dwEntryInfoSize:DWORD

LOCAL hHeap:HANDLE



and dwEntryInfoSize, 0



INVOKE RasGetEntryProperties, 0, 0, 0, ADDR dwEntryInfoSize, 0, 0

push dwEntryInfoSize

pop cb



invoke GetProcessHeap

mov hHeap, eax

invoke HeapAlloc, hHeap, HEAP_ZERO_MEMORY, dwEntryInfoSize

mov edi, eax



mov RASMemoryBuffer,eax

mov edi, eax

assume edi:PTR RASENTRYNAME

mov [edi].dwSize, SIZEOF(RASENTRYNAME)



INVOKE RasEnumEntries, 0, 0, edi, ADDR cb, ADDR cEntries

.if eax == ERROR_BUFFER_TOO_SMALL

	invoke HeapReAlloc, hHeap, HEAP_ZERO_MEMORY, edi, cb

	invoke RasEnumEntries, 0, 0, edi, ADDR cb, ADDR cEntries

.endif



;INVOKE PrintEAX, eax

cmp eax, 0 ;eax = ERROR_BUFFER_INVALID (code 610)

je lab3190 



INVOKE MessageBox, NULL, ADDR Str2, NULL, MB_OK

jmp lab3208

lab3190:



;...........



lab3208:

assume edi:nothing



invoke HeapFree, hHeap, 0, edi



;INVOKE GlobalFree, RASMemoryBuffer 

RET

GetDialUp ENDP



start:



invoke GetDialUp

invoke ExitProcess, 0

ret

end start

PS: Don't forget add padding to RASENTRYNAMEA definition, otherwise you can't correctly access its members.

Edited: I've tested it uder w98 only. As for w2k/xp, other members (dwFlags and szPhonebookPath) should be added, i guess, because its version >= 5.0.

Posted on 2002-09-24 02:37:47 by Four-F

Source code problem

I've just compiled some ex on msvc6 and satisfied myself that 3-padding is really added.
So...

w9x RASENTRYNAMEA

RASENTRYNAMEA STRUCT

    dwSize		dd	?

    szEntryName 	db	RAS_MaxEntryName + 1 dup(?)

		db	3 dup(?)

RASENTRYNAMEA ENDS

w2k, + RASENTRYNAMEA

RASENTRYNAMEA STRUCT

    dwSize		dd	?

    szEntryName 	db	RAS_MaxEntryName + 1 dup(?)

		db	3 dup(?)

    dwFlags	dd	?

    szPhonebookPath db	MAX_PATH + 1 dup(?)

    		db	3 dup(?)

RASENTRYNAMEA ENDS

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

Example for w2k:

.386

.model flat, stdcall

option casemap:none



include \masm32\include\windows.inc

include \masm32\include\user32.inc

include \masm32\include\kernel32.inc

include \masm32\include\rasapi32.inc



includelib \masm32\lib\user32.lib

includelib \masm32\lib\kernel32.lib

includelib \masm32\lib\rasapi32.lib



MAX_ENTRYES equ 20



RASENTRYNAMEA_ STRUCT

    dwSize		dd	?

    szEntryName 	db	RAS_MaxEntryName + 1 dup(?)

    		db	3 dup(?)

    dwFlags	dd	?

    szPhonebookPath db	MAX_PATH + 1 dup(?)

		db	3 dup(?)

RASENTRYNAMEA_ ENDS



.data

szCaption	db "Remote access phone book", 0

NewLine		db 10, 13, 0



.data?

buffer	CHAR	MAX_ENTRYES*256	dup(?)



.code



PhoneBook proc uses esi edi



LOCAL dwEntryInfoSize:DWORD

LOCAL hHeap:HANDLE

LOCAL cEntries:UINT



	and dwEntryInfoSize, 0

	invoke RasGetEntryProperties, 0, 0, 0, addr dwEntryInfoSize, 0, 0



	invoke GetProcessHeap

	mov hHeap, eax

	invoke HeapAlloc, hHeap, HEAP_ZERO_MEMORY, dwEntryInfoSize

	mov edi, eax

	assume edi:PTR RASENTRYNAMEA_

	mov [edi].dwSize, sizeof RASENTRYNAMEA_



	invoke RasEnumEntries, 0, 0, edi, addr dwEntryInfoSize, addr cEntries

	.if eax == ERROR_BUFFER_TOO_SMALL

		invoke HeapReAlloc, hHeap, HEAP_ZERO_MEMORY, edi, dwEntryInfoSize

		invoke RasEnumEntries, 0, 0, edi, addr dwEntryInfoSize, addr cEntries

	.endif



	.if eax == 0

		xor esi, esi

		.while esi < sizeof buffer

			.break .if [edi][esi].dwSize != sizeof RASENTRYNAMEA_

			invoke lstrcat, addr buffer, addr [edi][esi].szEntryName

			invoke lstrcat, addr buffer, addr NewLine

			add esi, sizeof RASENTRYNAMEA_

		.endw

		invoke MessageBox, NULL, addr buffer, addr szCaption, MB_OK

	.endif



	assume edi:nothing



	invoke HeapFree, hHeap, 0, edi



	ret



PhoneBook ENDP



start:

invoke PhoneBook

invoke ExitProcess, 0

ret

end start

Posted on 2002-09-25 05:16:12 by Four-F

Source code problem

???? ??????? Four-F
It is a very detailed answer
Thank you very much !

Posted on 2002-09-25 18:05:33 by martidim

Source code problem

??????????.

PS: "???? ???????" shoulb be "??????? ???????" :)

Posted on 2002-09-26 02:39:57 by Four-F

Source code problem

The #pragma directives in the .H files force DWORD alignment on Win32.

Posted on 2002-09-26 08:44:25 by bitRAKE

Source code problem

Now clear.

Posted on 2002-09-27 03:29:39 by Four-F

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