[janderwald] 66545: [NTOS] - use IopGetDeviceObjectFromDeviceInstance to retrieve PDO

Author: janderwald
Date: Mon Mar  2 19:14:16 2015
New Revision: 66545

URL: http://svn.reactos.org/svn/reactos?rev=66545&view=rev
Log:
[NTOS]
- use IopGetDeviceObjectFromDeviceInstance to retrieve PDO

Modified:
    trunk/reactos/ntoskrnl/io/iomgr/deviface.c

Modified: trunk/reactos/ntoskrnl/io/iomgr/deviface.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/io/iomgr/deviface....
==============================================================================
--- trunk/reactos/ntoskrnl/io/iomgr/deviface.c	[iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/io/iomgr/deviface.c	[iso-8859-1] Mon Mar  2 19:14:16 2015
@@ -17,6 +17,9 @@
 #include <debug.h>

/* FUNCTIONS *****************************************************************/
+
+PDEVICE_OBJECT
+IopGetDeviceObjectFromDeviceInstance(PUNICODE_STRING DeviceInstance);

static PWCHAR BaseKeyString = L"\Registry\Machine\System\CurrentControlSet\Control\DeviceClasses\";

@@ -1308,17 +1311,17 @@
                           IN BOOLEAN Enable)
 {
     PDEVICE_OBJECT PhysicalDeviceObject;
-    PFILE_OBJECT FileObject;
     UNICODE_STRING GuidString;
     PWCHAR StartPosition;
     PWCHAR EndPosition;
     NTSTATUS Status;
     LPCGUID EventGuid;
     HANDLE InstanceHandle, ControlHandle;
-    UNICODE_STRING KeyName;
+    UNICODE_STRING KeyName, DeviceInstance;
     OBJECT_ATTRIBUTES ObjectAttributes;
-    ULONG LinkedValue;
+    ULONG LinkedValue, Index;
     GUID DeviceGuid;
+

if (SymbolicLinkName == NULL)
         return STATUS_INVALID_PARAMETER_1;
@@ -1381,23 +1384,38 @@
         return Status;
     }

-    /* Get pointer to the PDO */
-    Status = IoGetDeviceObjectPointer(
-        SymbolicLinkName,
-        0, /* DesiredAccess */
-        &FileObject,
-        &PhysicalDeviceObject);
-    if (!NT_SUCCESS(Status))
-    {
-        DPRINT1("IoGetDeviceObjectPointer() failed with status 0x%08lx\n", Status);
-        return Status;
-    }
-
+    DeviceInstance.Buffer = ExAllocatePool(PagedPool, (ULONG_PTR)StartPosition - (ULONG_PTR)SymbolicLinkName->Buffer);
+    if (DeviceInstance.Buffer == NULL)
+    {
+        /* no memory */
+        return STATUS_INSUFFICIENT_RESOURCES;
+    }
+
+    DeviceInstance.MaximumLength = DeviceInstance.Length = ((ULONG_PTR)StartPosition - (ULONG_PTR)SymbolicLinkName->Buffer) - 5 * sizeof(WCHAR);
+    RtlCopyMemory(DeviceInstance.Buffer, &SymbolicLinkName->Buffer[4], DeviceInstance.Length);
+    for(Index = 0; Index < DeviceInstance.Length / sizeof(WCHAR); Index++)
+    {
+        if (DeviceInstance.Buffer[Index] == L'#')
+        {
+            DeviceInstance.Buffer[Index] = L'\';
+        }
+    }
+
+    PhysicalDeviceObject = IopGetDeviceObjectFromDeviceInstance(&DeviceInstance);
+    
+    if (!PhysicalDeviceObject)
+    {
+        DPRINT1("IopGetDeviceObjectFromDeviceInstance failed to find status %wZ\n", &DeviceInstance);
+        ExFreePool(DeviceInstance.Buffer);
+        return STATUS_NOT_FOUND;
+    }
+
+    ExFreePool(DeviceInstance.Buffer);
     Status = RtlGUIDFromString(&GuidString, &DeviceGuid);
     if (!NT_SUCCESS(Status))
     {
         DPRINT1("RtlGUIDFromString() failed with status 0x%08lx\n", Status);
-        ObDereferenceObject(FileObject);
+        ObDereferenceObject(PhysicalDeviceObject);
         return Status;
     }

@@ -1409,7 +1427,7 @@
         &DeviceGuid,
         (PVOID)SymbolicLinkName);

-    ObDereferenceObject(FileObject);
+    ObDereferenceObject(PhysicalDeviceObject);
     DPRINT("Status %x\n", Status);
     return STATUS_SUCCESS;
 }