Silly Little DLL QuestionL

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1 comment, last by F1N1TY 16 years ago
(Question had to have an L... ever other word in the title did :-P) Well, I'm trying to make a little windows hook, and I got the hook working, and all that's fine. But now, I'm having troubles sending a value from my DLL to my Executable. I'll just paste the code, and tell you what's going on: --------------------------
Executable
--------------------------
#include <windows.h>
#include <iostream>

extern "C" __declspec(dllimport) void InstallHook( );
extern "C" __declspec(dllimport) void UnInstallHook( );
extern "C" __declspec(dllimport) void GetX( int *px );
extern "C" __declspec(dllimport) void GetY( int *py );

int main()
{
	int x, y;
	InstallHook(  );

	do
	{
		GetX(&x);
		GetY(&y);
		std::cout << x << '\t' << y << std::endl;
		// Nothing
	}while( (x >= 5) && (y >= 5) ); 

	UnInstallHook();

	return 0;
}




--------------------------
DLL
--------------------------
#include <windows.h>

HHOOK hhk;
HINSTANCE dllInstance;
bool shown;
HWND shell;
HWND button;
RECT startRect;

int x = 10, y = 10;


LRESULT CALLBACK myMouseProc(int code, WPARAM wParam, LPARAM lParam);
extern "C"
{
	__declspec(dllexport) void InstallHook( );
	__declspec(dllexport) void UnInstallHook( );
	__declspec(dllexport) void GetY( int *py );
	__declspec(dllexport) void GetX( int *px );
}



BOOL WINAPI DllMain(HINSTANCE hInstance,DWORD fwdReason, LPVOID lpvReserved)
{
	dllInstance = hInstance;
	shown = true;

	shell = FindWindow(L"Shell_TrayWnd", NULL);
	button = FindWindowEx(shell, NULL, L"button", NULL);

	GetWindowRect(button, &startRect);		// Store the windows's rectangle in this rect.

	return(TRUE); 
}



extern "C" __declspec(dllexport) void InstallHook( )
{
	hhk = SetWindowsHookEx(WH_MOUSE, (HOOKPROC)&myMouseProc, dllInstance , NULL );
}

extern "C" __declspec(dllexport) void UnInstallHook( )
{
	if( !UnhookWindowsHookEx( hhk ) )
		MessageBox(NULL, L"NOT Uninstalled Bitch!", L"Yay!", MB_OK);

}

extern "C" __declspec(dllexport) void GetX( int *px )
{
	*px = x;
}

extern "C" __declspec(dllexport) void GetY( int *py )
{
	*py = y;
}

LRESULT CALLBACK myMouseProc(int code, WPARAM wParam, LPARAM lParam)
{	
	MOUSEHOOKSTRUCT * mouse_hook = (MOUSEHOOKSTRUCT *)(lParam);

	if (code < 0) // do not process message 
		return CallNextHookEx(hhk, code, wParam, lParam); 

	x = (int)mouse_hook->pt.x;
	y = (int)mouse_hook->pt.y;

	if( (x > (startRect.left - 1 ) ) && (x < startRect.right) )
	{
		if ( (y > startRect.top) && (y < startRect.bottom) )
			ShowWindow(button, 0);
	}
	else
		ShowWindow(button, 1);

	return(CallNextHookEx( hhk, code, wParam, lParam ) );

}


Basically, the output is constantly 10, for some reason, so the * = (int)mouse_hook->pt.* isn't working, for some reason. EDIT: sorry for the sloppy code, just trying to get things to work. BTW, this DOES compile (visual studio 2005).
"I'd rather know one thing, no matter how ordinary, than discourse endlessly on great issues." -- Galileo
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Nevermind.
For those interested, I had to create a shared data segment for the DLL, in order to alter the values.

Secondly, I had to change my x and y types to LONGs, since the POINT struct uses LONGs, not ints.

Looks something like this:

#pragma data_seg(".SHARED")LONG x = 0;LONG y = 0;#pragma data_seg()


With linker option:
/section:.SHARED,rws

Works like a charm, now :-)
"I'd rather know one thing, no matter how ordinary, than discourse endlessly on great issues." -- Galileo

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