reactos/drivers/dd/debugout/debugout.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:        See COPYING in the top level directory
   4  * PROJECT:          ReactOS kernel
   5  * FILE:             drivers/dd/debugout.c
   6  * PURPOSE:          Debug output device driver
   7  * PROGRAMMER:       Ge van Geldorp (ge@gse.nl)
   8  * UPDATE HISTORY:
   9  *              2003/05/22: Created
  10  * NOTES:
  11  * In your usermode application, do something like this:
  12  *
  13  *  DebugHandle = CreateFile("\\\\.\\DebugOut",
  14  *                           GENERIC_WRITE,
  15  *                           0,
  16  *                           NULL,
  17  *                           OPEN_EXISTING,
  18  *                           FILE_ATTRIBUTE_NORMAL,
  19  *                           NULL);
  20  *
  21  * and write to your hearts content to DebugHandle.
  22  */
  23
  24 /* INCLUDES */
  25 #include <ddk/ntddk.h>
  26
  27 NTSTATUS STDCALL
  28 DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath);
  29
  30 /* FUNCTIONS */
  31 static NTSTATUS STDCALL
  32 DebugOutDispatch(IN PDEVICE_OBJECT DeviceObject, IN PIRP Irp)
  33 {
  34   PIO_STACK_LOCATION piosStack = IoGetCurrentIrpStackLocation(Irp);
  35   NTSTATUS nErrCode;
  36   char *Start;
  37   char Buf[513];
  38   unsigned Remaining;
  39   unsigned Length;
  40
  41   nErrCode = STATUS_SUCCESS;
  42
  43   switch(piosStack->MajorFunction)
  44     {
  45       /* opening and closing handles to the device */
  46       case IRP_MJ_CREATE:
  47       case IRP_MJ_CLOSE:
  48         break;
  49
  50       /* write data */
  51       case IRP_MJ_WRITE:
  52         Remaining = piosStack->Parameters.Write.Length;
  53         Start = Irp->AssociatedIrp.SystemBuffer;
  54         while (0 < Remaining)
  55           {
  56             Length = Remaining;
  57             if (sizeof(Buf) - 1 < Length)
  58               {
  59                 Length = sizeof(Buf) - 1;
  60               }
  61             RtlCopyMemory(Buf, Start, Length);
  62             Buf[Length] = '\0';
  63             DbgPrint("%s", Buf);
  64             Remaining -= Length;
  65             Start += Length;
  66           }
  67
  68         Irp->IoStatus.Information = piosStack->Parameters.Write.Length;
  69         break;
  70
  71       /* read data */
  72       case IRP_MJ_READ:
  73         Irp->IoStatus.Information = 0;
  74         nErrCode = STATUS_END_OF_FILE;
  75         break;
  76
  77       /* unsupported operations */
  78       default:
  79         nErrCode = STATUS_NOT_IMPLEMENTED;
  80     }
  81
  82   Irp->IoStatus.Status = nErrCode;
  83   IoCompleteRequest(Irp, IO_NO_INCREMENT);
  84
  85   return nErrCode;
  86 }
  87
  88 static VOID STDCALL
  89 DebugOutUnload(PDRIVER_OBJECT DriverObject)
  90 {
  91 }
  92
  93 NTSTATUS STDCALL
  94 DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath)
  95 {
  96   PDEVICE_OBJECT DebugOutDevice;
  97   UNICODE_STRING DeviceName = RTL_CONSTANT_STRING(L"\\Device\\DebugOut");
  98   UNICODE_STRING DosName = RTL_CONSTANT_STRING(L"\\DosDevices\\DebugOut");
  99   NTSTATUS Status;
 100
 101   /* register driver routines */
 102   DriverObject->MajorFunction[IRP_MJ_CLOSE] = DebugOutDispatch;
 103   DriverObject->MajorFunction[IRP_MJ_CREATE] = DebugOutDispatch;
 104   DriverObject->MajorFunction[IRP_MJ_WRITE] = DebugOutDispatch;
 105   DriverObject->MajorFunction[IRP_MJ_READ] = DebugOutDispatch;
 106   /* DriverObject->MajorFunction[IRP_MJ_QUERY_INFORMATION] = DebugOutDispatch; */
 107   DriverObject->DriverUnload = DebugOutUnload;
 108
 109   /* create device */
 110   Status = IoCreateDevice(DriverObject, 0, &DeviceName, FILE_DEVICE_NULL,
 111                             0, FALSE, &DebugOutDevice);
 112   if (! NT_SUCCESS(Status))
 113     {
 114       return Status;
 115     }
 116
 117   Status = IoCreateSymbolicLink(&DosName, &DeviceName);
 118   if (! NT_SUCCESS(Status))
 119     {
 120     IoDeleteDevice(DebugOutDevice);
 121     return Status;
 122     }
 123
 124   DebugOutDevice->Flags |= DO_BUFFERED_IO;
 125
 126   return Status;
 127 }
 128
 129 /* EOF */