Fixed bugs in null device drivers, added zero stream device

svn path=/trunk/; revision=2897

reactos/drivers/dd/null/makefile

@@ -1,4 +1,4 @@
-# $Id: makefile,v 1.14 2001/08/21 20:13:11 chorns Exp $
+# $Id: makefile,v 1.15 2002/04/29 23:06:42 hyperion Exp $
 
 PATH_TO_TOP = ../../..
 
@@ -8,6 +8,8 @@ TARGET_NAME = null
 
 TARGET_OBJECTS = null.o
 
+TARGET_LFLAGS = -Wl,--file-alignment,0x20 -Wl,--section-alignment,0x20
+
 include $(PATH_TO_TOP)/rules.mak
 
 include $(TOOLS_PATH)/helper.mk

reactos/drivers/dd/null/null.c

@@ -1,4 +1,4 @@
-/* $Id: null.c,v 1.6 2002/02/08 02:57:08 chorns Exp $
+/* $Id: null.c,v 1.7 2002/04/29 23:06:42 hyperion Exp $
  *
  * COPYRIGHT:        See COPYING in the top level directory
  * PROJECT:          ReactOS kernel
@@ -6,62 +6,88 @@
  * PURPOSE:          NULL device driver
  * PROGRAMMER:       David Welch (welch@mcmail.com)
  * UPDATE HISTORY:
- *              13/08/98: Created
+ *              13/08/1998: Created
+ *              29/04/2002: Fixed bugs, added zero-stream device
  */
 
-/* INCLUDES ****************************************************************/
+/* INCLUDES */
-
 #include <ddk/ntddk.h>
+#include "null.h"
 
-/* FUNCTIONS **************************************************************/
+/* OBJECTS */
-
+static const NULL_EXTENSION nxNull = NullBitBucket;
-NTSTATUS NullWrite(PIRP Irp, PIO_STACK_LOCATION stk)
+static const NULL_EXTENSION nxZero = NullZeroStream;
-{
-   Irp->IoStatus.Information = stk->Parameters.Write.Length;
-   return(STATUS_SUCCESS);
-}
-
-NTSTATUS NullRead(PIRP Irp, PIO_STACK_LOCATION stk)
-{
-   Irp->IoStatus.Information = 0;
-   return(STATUS_END_OF_FILE);
-}
 
+/* FUNCTIONS */
 NTSTATUS STDCALL
 NullDispatch(PDEVICE_OBJECT DeviceObject, PIRP Irp)
-/*
- * FUNCTION: Handles user mode requests
- * ARGUMENTS:
- *           DeviceObject = Device for request
- *           Irp = I/O request packet describing request
- * RETURNS: Success or failure
- */
 {
-   PIO_STACK_LOCATION Stack = IoGetCurrentIrpStackLocation(Irp);
+ PIO_STACK_LOCATION piosStack = IoGetCurrentIrpStackLocation(Irp);
-   NTSTATUS status;
+ NTSTATUS nErrCode;
  
-   switch (Stack->MajorFunction)
+ nErrCode = STATUS_SUCCESS;
+
+ switch(piosStack->MajorFunction)
  {
+  /* opening and closing handles to the device */
   case IRP_MJ_CREATE:
   case IRP_MJ_CLOSE:
-	status = STATUS_SUCCESS;
+  {
    break;
+  }
 
+  /* write data */
   case IRP_MJ_WRITE:
-	status = NullWrite(Irp,Stack);
+  {
+   switch(NULL_DEVICE_TYPE(DeviceObject))
+   {
+    case NullBitBucket:
+     Irp->IoStatus.Information = piosStack->Parameters.Write.Length;
      break;
 
+    case NullZeroStream:
+    default:
+     Irp->IoStatus.Information = 0;
+     nErrCode = STATUS_NOT_IMPLEMENTED;
+   }
+
+   break;
+  }
+
+  /* read data */
   case IRP_MJ_READ:
-	status = NullRead(Irp,Stack);
+  {
+   switch(NULL_DEVICE_TYPE(DeviceObject))
+   {
+    case NullBitBucket:
+     Irp->IoStatus.Information = 0;
+     nErrCode = STATUS_END_OF_FILE;
+     break;
+
+    case NullZeroStream:
+     RtlZeroMemory(Irp->AssociatedIrp.SystemBuffer, piosStack->Parameters.Read.Length);
+     Irp->IoStatus.Information = piosStack->Parameters.Read.Length;
      break;
 
     default:
-        status = STATUS_NOT_IMPLEMENTED;
+     Irp->IoStatus.Information = 0;
+     nErrCode = STATUS_NOT_IMPLEMENTED;
    }
 
-   Irp->IoStatus.Status = status;
+   break;
-   IoCompleteRequest(Irp,IO_NO_INCREMENT);
+  }
-   return(status);
+
+  /* unsupported operations */
+  default:
+  {
+   nErrCode = STATUS_NOT_IMPLEMENTED;
+  }
+ }
+
+ Irp->IoStatus.Status = nErrCode;
+ IoCompleteRequest(Irp, IO_NO_INCREMENT);
+
+ return (nErrCode);
 }
 
 NTSTATUS STDCALL
@@ -72,34 +98,67 @@ NullUnload(PDRIVER_OBJECT DriverObject)
 
 NTSTATUS STDCALL 
 DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath)
-/*
- * FUNCTION: Called by the system to initalize the driver
- * ARGUMENTS:
- *           DriverObject = object describing this driver
- *           RegistryPath = path to our configuration entries
- * RETURNS: Success or failure
- */
 {
-   PDEVICE_OBJECT DeviceObject;
+ PDEVICE_OBJECT pdoNullDevice;
-   UNICODE_STRING DeviceName;
+ PDEVICE_OBJECT pdoZeroDevice;
-   NTSTATUS Status;
+ UNICODE_STRING wstrDeviceName;
+ NTSTATUS nErrCode;
 
-   DeviceObject->Flags=0;
+ /* register driver routines */
  DriverObject->MajorFunction[IRP_MJ_CLOSE] = NullDispatch;
  DriverObject->MajorFunction[IRP_MJ_CREATE] = NullDispatch;
  DriverObject->MajorFunction[IRP_MJ_WRITE] = NullDispatch;
  DriverObject->MajorFunction[IRP_MJ_READ] = NullDispatch;
+ /* DriverObject->MajorFunction[IRP_MJ_QUERY_INFORMATION] = NullDispatch; */
  DriverObject->DriverUnload = NullUnload;
 
-   RtlInitUnicodeString(&DeviceName,
+ /* create null device */
-                        L"\\Device\\Null");
+ RtlInitUnicodeString(&wstrDeviceName, L"\\Device\\Null");
-   Status = IoCreateDevice(DriverObject,
+
-                           0,
+ nErrCode = IoCreateDevice
-                           &DeviceName,
+ (
+  DriverObject,
+  sizeof(NULL_EXTENSION),
+  &wstrDeviceName,
   FILE_DEVICE_NULL,
   0,
   FALSE,
-                           &DeviceObject);
+  &pdoNullDevice
-   return (Status);
+ );
+
+ /* failure */
+ if(!NT_SUCCESS(nErrCode))
+ {
+  return (nErrCode);
+ }
+
+ pdoNullDevice->DeviceExtension = (PVOID)&nxNull;
+
+ /* create zero device */
+ RtlInitUnicodeString(&wstrDeviceName, L"\\Device\\Zero");
+
+ nErrCode = IoCreateDevice
+ (
+  DriverObject,
+  sizeof(NULL_EXTENSION),
+  &wstrDeviceName,
+  FILE_DEVICE_NULL,
+  FILE_READ_ONLY_DEVICE, /* zero device is read-only */
+  FALSE,
+  &pdoZeroDevice
+ );
+
+ /* failure */
+ if(!NT_SUCCESS(nErrCode))
+ {
+  IoDeleteDevice(pdoNullDevice);
+  return (nErrCode);
+ }
+
+ pdoZeroDevice->DeviceExtension = (PVOID)&nxZero;
+ pdoZeroDevice->Flags |= DO_BUFFERED_IO;
+
+ return (nErrCode);
 }
 
+/* EOF */

reactos/drivers/dd/null/null.h

@@ -0,0 +1,19 @@
+/* $Id: null.h,v 1.1 2002/04/29 23:06:42 hyperion Exp $
+ *
+ * COPYRIGHT:        See COPYING in the top level directory
+ * PROJECT:          ReactOS kernel
+ * FILE:             services/dd/null/null.h
+ * PURPOSE:          NULL device driver internal definitions
+ * PROGRAMMER:       KJK::Hyperion <noog@libero.it>
+ * UPDATE HISTORY:
+ *              29/04/2002: Created
+ */
+
+typedef enum __tagNULL_EXTENSION{
+ NullBitBucket,
+ NullZeroStream,
+} NULL_EXTENSION, *PNULL_EXTENSION;
+
+#define NULL_DEVICE_TYPE(__DEVICE__) (*((PNULL_EXTENSION)((__DEVICE__)->DeviceExtension)))
+
+/* EOF */