www.pudn.com > WDM_Driver_Dev_ExampleCode.zip > ReadReg.cpp

//	This code shows how to read the registry 
//	However it is not used by the current Wdm1 code 
 
void ReadReg( IN PUNICODE_STRING DriverRegistryPath) 
{ 
	// Make zero terminated copy of driver registry path 
	USHORT FromLen = DriverRegistryPath->Length; 
	PUCHAR wstrDriverRegistryPath = (PUCHAR)ExAllocatePool( PagedPool, FromLen+sizeof(WCHAR)); 
	if( wstrDriverRegistryPath==NULL) return; 
	RtlCopyMemory( wstrDriverRegistryPath, DriverRegistryPath->Buffer, FromLen); 
	RtlZeroMemory( wstrDriverRegistryPath+FromLen, sizeof(WCHAR)); 
 
	// Initialise our ULONG and UNICODE_STRING values 
	ULONG UlongValue = -1; 
	UNICODE_STRING UnicodeString; 
	UnicodeString.Buffer = NULL; 
	UnicodeString.MaximumLength = 0; 
	UnicodeString.Length = 0; 
 
	// Build up our registry query table 
	RTL_QUERY_REGISTRY_TABLE QueryTable[4]; 
	RtlZeroMemory( QueryTable, sizeof(QueryTable)); 
 
	QueryTable[0].Name  = L"Parameters"; 
	QueryTable[0].Flags = RTL_QUERY_REGISTRY_SUBKEY; 
	QueryTable[0].EntryContext = NULL; 
	QueryTable[1].Name  = L"UlongValue"; 
	QueryTable[1].Flags = RTL_QUERY_REGISTRY_DIRECT; 
	QueryTable[1].EntryContext = &UlongValue; 
	QueryTable[2].Name  = L""; // Default value 
	QueryTable[2].Flags = RTL_QUERY_REGISTRY_DIRECT; 
	QueryTable[2].EntryContext = &UnicodeString; 
 
	// Issue query 
	NTSTATUS status = RtlQueryRegistryValues( 
					   RTL_REGISTRY_ABSOLUTE, (PWSTR)wstrDriverRegistryPath, 
					   QueryTable, NULL, NULL); 
	// Print results 
	DebugPrint( "ReadReg %x: UlongValue %x UnicodeString %T", 
				status, UlongValue, &UnicodeString); 
 
	// Do not forget to free our buffer 
	ExFreePool(wstrDriverRegistryPath); 
}