convert struct from c++

[jpam]

i hope someone can help me out with this
i don't kmow how to write the line below in masm
CONAGetDevices is a function inside dll
loaded with LoadLibrary and GetProcAddress

c++ syntax:

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// Get list of currently connected devices
pDevices = new CONAPI_DEVICE[dwDeviceCount];
CONAGetDevices(hDMHandle, &dwDeviceCount, pDevices);

masm try:

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CD  CONAPI_DEVICE <>
push offset CD ; offset struct
push iCount    ; 1
push phDMHandle ; handle from CONAOpenDM function
call _CONAGetDevices

eax returns 80100012 (ECONA_INVALID_POINTER)

pop eax
pop eax
pop eax

the handle from CONAOpenDM is correct
because CONAGetDeviceCount is returning ok

CONAPI_DEVICE and Connection_info are C++ struct's

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// Device info structure
typedef struct
{
WCHAR* pstrSerialNumber;
WCHAR* pstrFriendlyName;
WCHAR* pstrModel;
WCHAR* pstrManufacturer;
DWORD dwNumberOfItems;
CONAPI_CONNECTION_INFO* pItems;
} CONAPI_DEVICE;

// Connection_info structure
typedef struct
{
DWORD dwDeviceID;
DWORD dwMedia;
WCHAR* pstrDeviceName;
WCHAR* pstrAddress;
DWORD dwState;
} CONAPI_CONNECTION_INFO;

i hoop i converted it right to masm syntax

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CONAPI_DEVICE struct

pstrSerialNumber dd ?
pstrFriendlyName dd ?
pstrModel        dd ?
pstrManufacturer dd ?
dwNumberOfItems  dd ?
pItems           dd ?

CONAPI_DEVICE ends

CONAPI_CONNECTION_INFO struct

dwDeviceID dd ?
dwMedia    dd ?
pstrDeviceName dd ?
pstrAddress    dd ?
dwState    dd ?

CONAPI_CONNECTION_INFO ends

[ToutEnMasm]

translate correct , but it was useless to do it

; Device info structure

CONAPI_DEVICE   STRUCT
   pstrSerialNumber DWORD ?
   pstrFriendlyName DWORD ?
   pstrModel DWORD ?
   pstrManufacturer DWORD ?
   dwNumberOfItems DWORD ?
   pItems DWORD ?
CONAPI_DEVICE      ENDS


; Connection_info structure

CONAPI_CONNECTION_INFO   STRUCT
   dwDeviceID DWORD ?
   dwMedia DWORD ?
   pstrDeviceName DWORD ?
   pstrAddress DWORD ?
   dwState DWORD ?
CONAPI_CONNECTION_INFO      ENDS

result given by http://www.masm32.com/board/index.php?topic=5428.0

[dedndave]

the "*" means it is a pointer, if i remember C correctly
so, yes - it is a dword in 32 bit code
the prefix "pstr" means it is a pointer to a string
so - these are addresses

[jpam]

Thanks people

But if the struct's are correct,
how to deal with this C++ command ?

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pDevices = new CONAPI_DEVICE[dwDeviceCount];

It looks like pDevices = pointer to Struct
i have try'ed many different inputs, like a pointer of a pointer, array of struct's and even memmory buffer
nothing is working,  still the same error invalid pointer 

[qWord]

how to deal with this C++ command ?

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pDevices = new CONAPI_DEVICE[dwDeviceCount];

should be:

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mov eax,dwDeviceCount
imul eax,eax,SIZEOF CONAPI_DEVICE
mov pDevices,alloc(eax)

qWord

[clive]

Not phDMAHandle?

CONAOpenDM
mov hDMHandle,eax

..

push hDMHandle ; handle from CONAOpenDM function

..

[jpam]

Code Select Expand

mov eax,dwDeviceCount
imul eax,eax,SIZEOF CONAPI_DEVICE
mov pDevices,alloc(eax)

Pointer to allocated memory
allready try that, error 80100012 (ECONA_INVALID_POINTER)

i got a brain dammage from this  :dazzled:

any ideas left   ::)

[jpam]

@clive

current code;

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invoke GetProcessHeap
mov hHeap,eax

mov eax,iCount
imul eax,eax,SIZEOF CONAPI_DEVICE
invoke HeapAlloc,hHeap,HEAP_ZERO_MEMORY,eax
mov pMem,eax
mov pDevices,eax

push pDevices
push iCount
push phDMHandle
call _CONAGetDevices
PrintHex eax,"_CONAGetDevices"
pop eax
pop eax
pop eax

[clive]

Try getting the compiler to generate code for you to look at. Use -FAcs or check the compiler options.

[dedndave]

Code Select Expand

// Parameters:
//  hDMHandle [in]  Device manager handle
//  pdwCount [in,out] In: Number of allocated CONAPI_DEVICE structs.
// Out: Number of used CONAPI_DEVICE structs.
//  pDevices [out] Pointer to receiving CONAPI_DEVICE structures.

pdwCount is a pointer to a dword that holds the number of structures on input
and receives the number of used structures on output
you are passing the count, instead

[jpam]

dedndave you are right !

aarch !, bad manual reading from me  :(
when i pass the pointer of the dword its working !

many thanks all you people for helping me !
:U