C Translation

[ragdog]

Hi

I have allready a problem to convert a C.h to inc

proto stdcall :HWND, :LPCTSTR, :LPRECT

error A2006: undefined symbol : LPRECT
error A2195: parameter or local cannot have void type
error A2131: VARARG parameter requires C calling convention

Have you any idea to translate it?

[dedndave]

stdcall is already a defined symbol with masm

[MichaelW]

If the function declaration (prototype) in the C header file specified __stdcall, then it means that the function uses the STDCALL calling convention:

http://msdn.microsoft.com/en-us/library/zxk0tw93(v=VS.90).aspx

If in your assembly source STDCALL is specified in the language field of the model directive:

.model flat, stdcall       ; 32 bit memory model

Then unless your function declaration (PROTO) for the C function specifies a different calling convention, INVOKE will use STDCALL. So in other words, if the C function that you are prototyping uses STDCALL, then you can skip the langtype attribute in the function declaration (PROTO).

The header files tend to use a complex system of declarations, where new symbols are defined in terms of previously defined symbols. So, for example, in WinDef.h you see:

#define WINAPI      __stdcall

Which basically assigns __stdcall to the symbol WINAPI. See:

http://msdn.microsoft.com/en-US/library/teas0593(v=VS.80).aspx

So for example in the header file WinGdi.h, you can read this declaration:

WINGDIAPI int WINAPI GetClipBox( IN HDC,  OUT LPRECT);

As:

int __stdcall GetClipBox( IN HDC, OUT LPRECT);

Note that I ignored the WINGDIAPI because it is not meaningful for your purposes.

http://msdn.microsoft.com/en-us/library/9w92dxk3.aspx

The MASM32 windows.inc includes many of the definitions that you find in the header files, for example:

HDC                         typedef DWORD
HWND                        typedef DWORD
LPCTSTR                     typedef DWORD

LPRECT is not included, but you could easily add it to your copy, or place the definition at the top of your source. In 32-bit code you can safely assume that a pointer will be a DWORD. So for example, assuming that LPRECT had been defined, the prototype for GetClipBox could then be:

GetClipBox PROTO :HDC, :LPRECT

The actual prototype in gdi32.inc is:

GetClipBox PROTO :DWORD,:DWORD