[tfaber] 64946: [NTOS:IO] - Normalize, er.. simplify IopNormalizeImagePath a bit and use pool tagging

Author: tfaber
Date: Thu Oct 23 22:05:56 2014
New Revision: 64946

URL: http://svn.reactos.org/svn/reactos?rev=64946&view=rev
Log:
[NTOS:IO]
- Normalize, er.. simplify IopNormalizeImagePath a bit and use pool tagging

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

Modified: trunk/reactos/ntoskrnl/io/iomgr/driver.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/io/iomgr/driver.c?...
==============================================================================
--- trunk/reactos/ntoskrnl/io/iomgr/driver.c	[iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/io/iomgr/driver.c	[iso-8859-1] Thu Oct 23 22:05:56 2014
@@ -239,39 +239,44 @@
          PUNICODE_STRING ImagePath,
     _In_ PUNICODE_STRING ServiceName)
 {
+    UNICODE_STRING SystemRootString = RTL_CONSTANT_STRING(L"\SystemRoot\");
+    UNICODE_STRING DriversPathString = RTL_CONSTANT_STRING(L"\SystemRoot\system32\drivers\");
+    UNICODE_STRING DotSysString = RTL_CONSTANT_STRING(L".sys");
     UNICODE_STRING InputImagePath;

DPRINT("Normalizing image path '%wZ' for service '%wZ'\n", ImagePath, ServiceName);

-    RtlCopyMemory(&InputImagePath,
-                  ImagePath,
-                  sizeof(UNICODE_STRING));
-
+    InputImagePath = *ImagePath;
     if (InputImagePath.Length == 0)
     {
         ImagePath->Length = 0;
-        ImagePath->MaximumLength =
-            (33 * sizeof(WCHAR)) + ServiceName->Length + sizeof(UNICODE_NULL);
-        ImagePath->Buffer = ExAllocatePool(NonPagedPool,
-                                           ImagePath->MaximumLength);
+        ImagePath->MaximumLength = DriversPathString.Length +
+                                   ServiceName->Length +
+                                   DotSysString.Length +
+                                   sizeof(UNICODE_NULL);
+        ImagePath->Buffer = ExAllocatePoolWithTag(NonPagedPool,
+                                                  ImagePath->MaximumLength,
+                                                  TAG_IO);
         if (ImagePath->Buffer == NULL)
             return STATUS_NO_MEMORY;

-        RtlAppendUnicodeToString(ImagePath, L"\SystemRoot\system32\drivers\");
+        RtlCopyUnicodeString(ImagePath, &DriversPathString);
         RtlAppendUnicodeStringToString(ImagePath, ServiceName);
-        RtlAppendUnicodeToString(ImagePath, L".sys");
+        RtlAppendUnicodeStringToString(ImagePath, &DotSysString);
     }
     else if (InputImagePath.Buffer[0] != L'\')
     {
         ImagePath->Length = 0;
-        ImagePath->MaximumLength =
-            12 * sizeof(WCHAR) + InputImagePath.Length + sizeof(UNICODE_NULL);
-        ImagePath->Buffer = ExAllocatePool(NonPagedPool,
-                                           ImagePath->MaximumLength);
+        ImagePath->MaximumLength = SystemRootString.Length +
+                                   InputImagePath.Length +
+                                   sizeof(UNICODE_NULL);
+        ImagePath->Buffer = ExAllocatePoolWithTag(NonPagedPool,
+                                                  ImagePath->MaximumLength,
+                                                  TAG_IO);
         if (ImagePath->Buffer == NULL)
             return STATUS_NO_MEMORY;

-        RtlAppendUnicodeToString(ImagePath, L"\SystemRoot\");
+        RtlCopyUnicodeString(ImagePath, &SystemRootString);
         RtlAppendUnicodeStringToString(ImagePath, &InputImagePath);

/* Free caller's string */
@@ -319,8 +324,7 @@
         ServiceStart = 0;

/* IopNormalizeImagePath will do all of the work for us if we give it an empty string */
-        ServiceImagePath.Length = ServiceImagePath.MaximumLength = 0;
-        ServiceImagePath.Buffer = NULL;
+        RtlInitEmptyUnicodeString(&ServiceImagePath, NULL, 0);
     }
     else
     {