reactos/rostests/apitests/w32knapi/w32knapi.c

#include "w32knapi.h"

HINSTANCE g_hInstance;
HMODULE g_hModule = NULL;
PGDI_TABLE_ENTRY GdiHandleTable;

static
PGDI_TABLE_ENTRY
MyGdiQueryTable()
{
	PTEB pTeb = NtCurrentTeb();
	PPEB pPeb = pTeb->ProcessEnvironmentBlock;
	return pPeb->GdiSharedHandleTable;
}

BOOL
IsHandleValid(HGDIOBJ hobj)
{
    USHORT Index = (ULONG_PTR)hobj;
    PGDI_TABLE_ENTRY pentry = &GdiHandleTable[Index];

    if (pentry->KernelData == NULL ||
        pentry->KernelData < (PVOID)0x80000000 ||
        (USHORT)pentry->FullUnique != (USHORT)((ULONG_PTR)hobj >> 16))
    {
        return FALSE;
    }
    
    return TRUE;
}

PVOID
GetHandleUserData(HGDIOBJ hobj)
{
    USHORT Index = (ULONG_PTR)hobj;
    PGDI_TABLE_ENTRY pentry = &GdiHandleTable[Index];

    if (pentry->KernelData == NULL ||
        pentry->KernelData < (PVOID)0x80000000 ||
        (USHORT)pentry->FullUnique != (USHORT)((ULONG_PTR)hobj >> 16))
    {
        return NULL;
    }

    return pentry->UserData;
}


static DWORD WINAPI
IntSyscall(FARPROC proc, UINT cParams, PVOID pFirstParam)
{
	DWORD retval;

#ifdef __GNUC__
	asm volatile
	(
		"pushfl;"				// Save flags
		"movl %%ecx, %%eax;"
		"shl $2, %%eax;"		// Calculate param size
		"subl %%eax, %%esp;"	// Calculate new stack pos
		"movl %%esp, %%edi;"	// Destination is stackpointer
		"cld;"					// Clear direction flag
		"rep movsd;"			// Copy params to the stack
		"call *%%edx;"			// Call function
		"popfl;"				// Restore flags
		: "=a" (retval)
		: "S" (pFirstParam), "c" (cParams), "d"(proc)
		: "%edi"
	);
#else
	__asm
	{
		pushf
		mov eax, cParams
		shl eax, 2
		sub esp, eax
		mov edi, esp
		cld
		rep movsd
		call proc
		mov retval, eax
		popf
    };
#endif

	return retval;
}

DWORD
Syscall(LPWSTR pszFunction, int cParams, void* pParams)
{
	char szFunctionName[MAX_PATH];
	FARPROC proc;

	sprintf(szFunctionName, "%ls", pszFunction);
	proc = (FARPROC)GetProcAddress(g_hModule, szFunctionName);
	if (!proc)
	{
		printf("Couldn't find proc: %s\n", szFunctionName);
		return FALSE;
	}

	return IntSyscall(proc, cParams, pParams);
}

BOOL
IsFunctionPresent(LPWSTR lpszFunction)
{
	char szFunctionName[MAX_PATH];
	sprintf(szFunctionName, "%ls", lpszFunction);
	return (GetProcAddress(g_hModule, szFunctionName) != NULL);
}

int APIENTRY
WinMain(HINSTANCE hInstance,
        HINSTANCE hPrevInstance,
        LPSTR     lpCmdLine,
        int       nCmdShow)
{
	g_hInstance = hInstance;

	printf("Win32k native API test\n");

	/* Convert to gui thread */
	// IsGUIThread(TRUE); <- does not exists on win2k

	InitOsVersion();
	printf("g_OsIdx = %d\n", g_OsIdx);

	g_hModule = LoadLibraryW(L"w32kdll.dll");
	if (!g_hModule)
	{
		printf("w32kdll.dll not found!\n");
		return -1;
	}

	GdiHandleTable = MyGdiQueryTable();
	if(!GdiHandleTable)
	{
		FreeLibrary(g_hModule);
		printf("GdiHandleTable not found!\n");
		return -1;
	}

	printf("\n");

	return TestMain(L"w32knapi", L"win32k.sys Nt-Api");
}