驅動程式 - Windows Driver Model (WDM) - 使用範例 - Pascal (DDDK) - Handle File IRP - Choose DO_DIRECT_IO

參考資訊：
https://wasm.in/
http://four-f.narod.ru/
https://github.com/steward-fu/ddk

main.pas

unit main;
 
interface
    uses
        DDDK;
         
    const
        DEV_NAME = '\Device\MyDriver';
        SYM_NAME = '\DosDevices\MyDriver';
 
    function _DriverEntry(pMyDriver : PDRIVER_OBJECT; pMyRegistry : PUNICODE_STRING) : NTSTATUS; stdcall;
 
implementation
var
    pNextDevice : PDEVICE_OBJECT;
    szBuf : array[0..255] of char;
     
procedure Unload(pMyDriver : PDRIVER_OBJECT); stdcall;
begin
end;
 
function IrpFile(pMyDevice : PDEVICE_OBJECT; pIrp : PIRP) : NTSTATUS; stdcall;
var
    dwLen : ULONG;
    pStack : PIO_STACK_LOCATION;
     
begin
    dwLen := 0;
    pStack := IoGetCurrentIrpStackLocation(pIrp);
    case pStack^.MajorFunction of
    IRP_MJ_CREATE:
        DbgPrint('IRP_MJ_CREATE', []);
    IRP_MJ_READ:
        begin
            DbgPrint('IRP_MJ_READ', []);
            dwLen := strlen(@szBuf[0]);
            memcpy(MmGetSystemAddressForMdlSafe(pIrp^.MdlAddress, LowPagePriority), @szBuf[0], dwLen);    
        end;
    IRP_MJ_WRITE:
        begin
            DbgPrint('IRP_MJ_WRITE', []);
            dwLen := MmGetMdlByteCount(pIrp^.MdlAddress);
            memcpy(@szBuf[0], MmGetSystemAddressForMdlSafe(pIrp^.MdlAddress, LowPagePriority), dwLen);
            DbgPrint('Buffer: %s, Length: %d', [szBuf, dwLen]);
        end;
    IRP_MJ_CLOSE:
        DbgPrint('IRP_MJ_CLOSE', []);
    end;
     
    Result := STATUS_SUCCESS;
    pIrp^.IoStatus.Status := Result;
    pIrp^.IoStatus.Information := dwLen;
    IoCompleteRequest(pIrp, IO_NO_INCREMENT);
end;
 
function IrpPnp(pMyDevice : PDEVICE_OBJECT; pIrp : PIRP) : NTSTATUS; stdcall;
var
    pStack : PIO_STACK_LOCATION;
    suSymName : UNICODE_STRING;
      
begin
    pStack := IoGetCurrentIrpStackLocation(pIrp);
    if pStack^.MinorFunction = IRP_MN_REMOVE_DEVICE then
        begin
            RtlInitUnicodeString(@suSymName, SYM_NAME);
            IoDetachDevice(pNextDevice);
            IoDeleteDevice(pMyDevice);
            IoDeleteSymbolicLink(@suSymName);
            IoCompleteRequest(pIrp, IO_NO_INCREMENT);
            Result := STATUS_SUCCESS;
        end
    else
        begin
            IoSkipCurrentIrpStackLocation(pIrp);
            Result := IoCallDriver(pNextDevice, pIrp);
        end;
end;
 
function AddDevice(pMyDriver : PDRIVER_OBJECT; pPhyDevice : PDEVICE_OBJECT) : NTSTATUS; stdcall;
var
    suDevName : UNICODE_STRING;
    suSymName : UNICODE_STRING;
    pMyDevice : PDEVICE_OBJECT;
     
begin
    RtlInitUnicodeString(@suDevName, DEV_NAME);
    RtlInitUnicodeString(@suSymName, SYM_NAME);
    IoCreateDevice(pMyDriver, 0, @suDevName, FILE_DEVICE_UNKNOWN, 0, FALSE, pMyDevice);
    pNextDevice := IoAttachDeviceToDeviceStack(pMyDevice, pPhyDevice);
    pMyDevice^.Flags := pMyDevice^.Flags or DO_DIRECT_IO;
    pMyDevice^.Flags := pMyDevice^.Flags and not DO_DEVICE_INITIALIZING;
    Result := IoCreateSymbolicLink(@suSymName, @suDevName);
end;
 
function _DriverEntry(pMyDriver : PDRIVER_OBJECT; pMyRegistry : PUNICODE_STRING) : NTSTATUS; stdcall;
begin
    pMyDriver^.MajorFunction[IRP_MJ_PNP]    := @IrpPnp;
    pMyDriver^.MajorFunction[IRP_MJ_CREATE] := @IrpFile;
    pMyDriver^.MajorFunction[IRP_MJ_READ]   := @IrpFile;
    pMyDriver^.MajorFunction[IRP_MJ_WRITE]  := @IrpFile;
    pMyDriver^.MajorFunction[IRP_MJ_CLOSE]  := @IrpFile;
    pMyDriver^.DriverExtension^.AddDevice   := @AddDevice;
    pMyDriver^.DriverUnload := @Unload;
    Result := STATUS_SUCCESS;
end;
end.

完成