代碼:
//METHOD_OUT_DIREC方式
NTSTATUS COMM_DirectOutIo(PIRP Irp, PIO_STACK_LOCATION pIoStackIrp, UINT *sizeofWrite)
{
NTSTATUS status = STATUS_UNSUCCESSFUL;
PVOID pInputBuffer, pOutputBuffer;
ULONG outputLength, inputLength;
DbgPrint("COMM_DirectOutIo\r\n");
outputLength = pIoStackIrp->Parameters.DeviceIoControl.OutputBufferLength;
inputLength = pIoStackIrp->Parameters.DeviceIoControl.InputBufferLength;
pInputBuffer = Irp->AssociatedIrp.SystemBuffer;
pOutputBuffer = NULL;
if(Irp->MdlAddress)
pOutputBuffer = MmGetSystemAddressForMdlSafe(Irp->MdlAddress, NormalPagePriority);
if(pInputBuffer && pOutputBuffer)
{
DbgPrint("COMM_DirectOutIo UserModeMessage = '%s'", pInputBuffer);
RtlCopyMemory(pOutputBuffer, pInputBuffer, outputLength);
*sizeofWrite = outputLength;
status = STATUS_SUCCESS;
}
return status;
}
// METHOD_IN_DIRECT
NTSTATUS COMM_DirectInIo(PIRP Irp, PIO_STACK_LOCATION pIoStackIrp, UINT *sizeofWrite)
{
NTSTATUS status = STATUS_UNSUCCESSFUL;
PVOID pInputBuffer, pOutputBuffer;
ULONG outputLength, inputLength;
DbgPrint("COMM_DirectInIo\r\n");
outputLength = pIoStackIrp->Parameters.DeviceIoControl.OutputBufferLength;
inputLength = pIoStackIrp->Parameters.DeviceIoControl.InputBufferLength;
pInputBuffer = Irp->AssociatedIrp.SystemBuffer;
pOutputBuffer = NULL;
if(Irp->MdlAddress)
pOutputBuffer = MmGetSystemAddressForMdlSafe(Irp->MdlAddress, NormalPagePriority);
if(pInputBuffer && pOutputBuffer)
{
DbgPrint("COMM_DirectInIo UserModeMessage = '%s'", pInputBuffer);
RtlCopyMemory(pOutputBuffer, pInputBuffer, outputLength);
*sizeofWrite = outputLength;
status = STATUS_SUCCESS;
}
return status;
}
// METHOD_BUFFERED
NTSTATUS COMM_BufferedIo(PIRP Irp, PIO_STACK_LOCATION pIoStackIrp, UINT *sizeofWrite)
{
NTSTATUS status = STATUS_UNSUCCESSFUL;
PVOID pInputBuffer, pOutputBuffer;
ULONG outputLength, inputLength;
DbgPrint("COMM_BufferedIo\r\n");
outputLength = pIoStackIrp->Parameters.DeviceIoControl.OutputBufferLength;
inputLength = pIoStackIrp->Parameters.DeviceIoControl.InputBufferLength;
pInputBuffer = Irp->AssociatedIrp.SystemBuffer;
pOutputBuffer = Irp->AssociatedIrp.SystemBuffer;
if(pInputBuffer && pOutputBuffer)
{
DbgPrint("COMM_BufferedIo UserModeMessage = '%s'", pInputBuffer);
RtlCopyMemory(pOutputBuffer, pInputBuffer, outputLength);
*sizeofWrite = outputLength;
status = STATUS_SUCCESS;
}
return status;
}
// METHOD_NEITHER
NTSTATUS COMM_NeitherIo(PIRP Irp, PIO_STACK_LOCATION pIoStackIrp, UINT *sizeofWrite)
{
NTSTATUS status = STATUS_UNSUCCESSFUL;
PVOID pInputBuffer, pOutputBuffer;
ULONG outputLength, inputLength;
DbgPrint("COMM_NeitherIo\r\n");
outputLength = pIoStackIrp->Parameters.DeviceIoControl.OutputBufferLength;
inputLength = pIoStackIrp->Parameters.DeviceIoControl.InputBufferLength;
pInputBuffer = pIoStackIrp->Parameters.DeviceIoControl.Type3InputBuffer;
pOutputBuffer = Irp->UserBuffer;
if(pInputBuffer && pOutputBuffer)
{
DbgPrint("COMM_NeitherIo UserModeMessage = '%s'", pInputBuffer);
RtlCopyMemory(pOutputBuffer, pInputBuffer, outputLength);
*sizeofWrite = outputLength;
status = STATUS_SUCCESS;
}
return status;
}
代碼比較簡單，都是取得輸入的數據，然后把數據直接拷貝到輸出，傳輸給應用層。
應用層的代碼：
procedure TfrmMain.Send_Recv_Data(AInData: String; var AOutData:String;
IoctlCode: DWORD);
var
dwReturn: DWORD;
inData:array[0..1023] of char;
outData:array[0..1023] of char;
begin
StrPCopy(inData, AInData);
if m_hCommDevice <> 0 then
begin
DeviceIoControl(m_hCommDevice, IoctlCode, @inData, Length(inData), @outData, Length(outData), dwReturn, nil);
AOutData := StrPas(@outData);
end;
end;
上面是進行發送和接受的過程。
代碼:
procedure TfrmMain. btnDirect_IN_IOClick (Sender: TObject);
var
outData:String;
begin
Send_Recv_Data(Trim(edtDirect_in_in.Text), outData, IOCTL_COMM_DIRECT_IN_IO);
edtDirect_in_out.Text := outData;
end;
這是 direct_in方式通信，其他通信方式類似，大家可以參考代碼了，這里就不列舉了，由于代碼比較簡單，我就不多說了，大家還是看代碼吧，很好明白。最后，給個測試圖：