driverentry.c

老外写的一个相当不错的虚拟显示器驱动

#include "Driver.h"

NTSTATUS CreateDevice(IN PDRIVER_OBJECT DriverObject, IN ULONG DeviceNumber);

#ifdef ALLOC_PRAGMA
#pragma alloc_text (INIT, DriverEntry)
#pragma alloc_text (INIT, CreateDevice)
#endif



PDEVICE_OBJECT		Devices[16];		// Global variable to store pointers to the device objects we create.


/*************************************************************************************************/
NTSTATUS DriverEntry(IN PDRIVER_OBJECT DriverObject,IN PUNICODE_STRING UniRegistryPath)
{
	// Initialize the driver object with this driver's entry points.
	DriverObject->MajorFunction[IRP_MJ_CREATE]			= DispatchCreate;
	DriverObject->MajorFunction[IRP_MJ_CLOSE]			= DispatchClose;
	DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL]		= DispatchDevCtrl;
	DriverObject->MajorFunction[IRP_MJ_READ]			= DispatchRead;
	DriverObject->DriverUnload					= Unload;

	// Create a device object.
	CreateDevice(DriverObject, 0);

	return STATUS_SUCCESS;
}


/*************************************************************************************************/
NTSTATUS CreateDevice(IN PDRIVER_OBJECT DriverObject, IN ULONG DeviceNumber)
{
	NTSTATUS status;
	PFDO_DATA deviceExtension;
	UNICODE_STRING deviceName, portName, linkName, number;
	WCHAR deviceNameBuffer[256];
	WCHAR portNameBuffer[256];
	WCHAR linkNameBuffer[256];
	WCHAR numberBuffer[20];
	HANDLE threadHandle;

	// Initialise strings
	number.Buffer = numberBuffer;
	number.MaximumLength = 20;
	deviceName.Buffer = deviceNameBuffer;
	deviceName.MaximumLength = 256*2;
	portName.Buffer = portNameBuffer;
	portName.MaximumLength = 256*2;
	linkName.Buffer = linkNameBuffer;
	linkName.MaximumLength = 256*2;

   	// Form the base NT device name...
	deviceName.Length = 0;
   	RtlAppendUnicodeToString(&deviceName, L"\\Device\\SAMPLEDEV");
	number.Length = 0;
	RtlIntegerToUnicodeString(DeviceNumber, 10, &number); 
	RtlAppendUnicodeStringToString(&deviceName, &number);

	// Create a Device object for this device...
	status = IoCreateDevice(DriverObject, sizeof(FDO_DATA), &deviceName, FILE_DEVICE_UNKNOWN, FILE_DEVICE_SECURE_OPEN, FALSE, &(Devices[DeviceNumber]));
	if (!NT_SUCCESS(status))
	{
		Devices[DeviceNumber] = NULL;
		return status;
	}

	Devices[DeviceNumber]->Flags |= DO_DIRECT_IO;

	// Initialize the Device Extension
	deviceExtension = Devices[DeviceNumber]->DeviceExtension;
	RtlZeroMemory(deviceExtension, sizeof(FDO_DATA));

	deviceExtension->DeviceObject = Devices[DeviceNumber];

   	// Form the Win32 symbolic link name.
	linkName.Length = 0;
	RtlAppendUnicodeToString(&linkName, L"\\DosDevices\\SAMPLEDEV");
	number.Length = 0;
	RtlIntegerToUnicodeString(DeviceNumber, 10, &number); 
	RtlAppendUnicodeStringToString(&linkName, &number);

	// Create a symbolic link so our device is visible to Win32...
 	status = IoCreateSymbolicLink(&linkName, &deviceName);
	if(!NT_SUCCESS(status)) 
	{
		IoDeleteDevice(Devices[DeviceNumber]);
		Devices[DeviceNumber] = NULL;
		return status;
	}

	// Initialize our custom IRP queues and create a thread for sending messages.
	KeInitializeSpinLock(&deviceExtension->ReadQueueLock);
	InitializeListHead(&deviceExtension->ReadIrpQueue);
	IoCsqInitialize(&deviceExtension->CSReadQueue, CSReadInsertIrp, CSReadRemoveIrp, CSReadPeekNextIrp, CSReadAcquireLock, CSReadReleaseLock, CSReadCompleteCanceledIrp);
	
	Devices[DeviceNumber]->Flags &= ~DO_DEVICE_INITIALIZING;

	return status;
}