Fix bugs in RegQueryValueExA() and RegQueryValueExW() that caused crashes or returned bogus
 information if the caller wants to retrieve the value data length only.
This fixes some bugs with regedit.

reactos/lib/advapi32/reg

diff -u -r1.44 -r1.45
--- reg.c	25 Feb 2004 14:25:10 -0000	1.44
+++ reg.c	1 Apr 2004 13:53:08 -0000	1.45
@@ -1,4 +1,4 @@

-/* $Id: reg.c,v 1.44 2004/02/25 14:25:10 ekohl Exp $

+/* $Id: reg.c,v 1.45 2004/04/01 13:53:08 ekohl Exp $

  *
  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS system libraries

@@ -2191,10 +2191,10 @@

       ErrorCode = RtlNtStatusToDosError (Status);
       SetLastError (ErrorCode);
       MaxCopy = 0;

-      if (NULL != lpcbData)
-        {
-          ResultSize = sizeof(*ValueInfo) + *lpcbData;
-        }

+      if (lpcbData != NULL)
+	{
+	  ResultSize = sizeof(*ValueInfo) + *lpcbData;
+	}

     }
 
   if (lpType != NULL)

@@ -2202,27 +2202,35 @@

       *lpType = ValueInfo->Type;
     }
 

-  if (NT_SUCCESS(Status))
-    RtlMoveMemory (lpData,
-		   ValueInfo->Data,
-		   min(ValueInfo->DataLength,MaxCopy));

+  if (NT_SUCCESS(Status) && lpData != NULL)
+    {
+      RtlMoveMemory (lpData,
+		     ValueInfo->Data,
+		     min(ValueInfo->DataLength, MaxCopy));
+    }

 
   if ((ValueInfo->Type == REG_SZ) ||
       (ValueInfo->Type == REG_MULTI_SZ) ||
       (ValueInfo->Type == REG_EXPAND_SZ))
     {

-      if (MaxCopy > ValueInfo->DataLength)
-	((PWSTR)lpData)[ValueInfo->DataLength / sizeof(WCHAR)] = 0;
-      
-      if (lpcbData) {
-	*lpcbData = (ResultSize - sizeof(*ValueInfo));
-	DPRINT("(string) Returning Size: %d\n", *lpcbData);
-      }

+      if (lpData != NULL && MaxCopy > ValueInfo->DataLength)
+	{
+	  ((PWSTR)lpData)[ValueInfo->DataLength / sizeof(WCHAR)] = 0;
+	}
+
+      if (lpcbData != NULL)
+	{
+	  *lpcbData = (ResultSize - sizeof(*ValueInfo));
+	  DPRINT("(string) Returning Size: %lu\n", *lpcbData);
+	}

     }
   else

-    if (lpcbData) {
-      *lpcbData = ResultSize - sizeof(*ValueInfo);
-      DPRINT("(other) Returning Size: %d\n", *lpcbData);

+    {
+      if (lpcbData != NULL)
+	{
+	  *lpcbData = ResultSize - sizeof(*ValueInfo);
+	  DPRINT("(other) Returning Size: %lu\n", *lpcbData);
+	}

     }
 
   DPRINT("Type %d  Size %d\n", ValueInfo->Type, ValueInfo->DataLength);

@@ -2255,7 +2263,7 @@

   DWORD Length;
   DWORD Type;
 

-  if ((lpData) && (!lpcbData))

+  if (lpData != NULL && lpcbData == NULL)

     {
       SetLastError(ERROR_INVALID_PARAMETER);
       return ERROR_INVALID_PARAMETER;

@@ -2269,10 +2277,10 @@

 					  0,
 					  ValueData.MaximumLength);
       if (!ValueData.Buffer)

-        {
-          SetLastError(ERROR_OUTOFMEMORY);
-          return ERROR_OUTOFMEMORY;
-        }

+	{
+	  SetLastError(ERROR_OUTOFMEMORY);
+	  return ERROR_OUTOFMEMORY;
+	}

     }
   else
     {

@@ -2284,42 +2292,52 @@

   RtlCreateUnicodeStringFromAsciiz (&ValueName,
 				    (LPSTR)lpValueName);
 

-  /* Convert length from USHORT to DWORD */
-  Length = ValueData.Length;

+  Length = *lpcbData * sizeof(WCHAR);

   ErrorCode = RegQueryValueExW (hKey,
 				ValueName.Buffer,
 				lpReserved,
 				&Type,
 				(LPBYTE)ValueData.Buffer,
 				&Length);

-  if (lpType != NULL)
-    *lpType = Type;

+  DPRINT("ErrorCode %lu\n", ErrorCode);

-  if ((ErrorCode == ERROR_SUCCESS) && (ValueData.Buffer != NULL))

+  if (ErrorCode == ERROR_SUCCESS ||
+      ErrorCode == ERROR_MORE_DATA)

     {

+      if (lpType != NULL)
+	{
+	  *lpType = Type;
+	}
+

       if ((Type == REG_SZ) || (Type == REG_MULTI_SZ) || (Type == REG_EXPAND_SZ))
 	{

-	  RtlInitAnsiString(&AnsiString, NULL);
-	  AnsiString.Buffer = lpData;
-	  AnsiString.MaximumLength = *lpcbData;
-	  ValueData.Length = Length;
-	  ValueData.MaximumLength = ValueData.Length + sizeof(WCHAR);
-	  RtlUnicodeStringToAnsiString(&AnsiString, &ValueData, FALSE);

+	  if (ErrorCode == ERROR_SUCCESS && ValueData.Buffer != NULL)
+	    {
+	      RtlInitAnsiString(&AnsiString, NULL);
+	      AnsiString.Buffer = lpData;
+	      AnsiString.MaximumLength = *lpcbData;
+	      ValueData.Length = Length;
+	      ValueData.MaximumLength = ValueData.Length + sizeof(WCHAR);
+	      RtlUnicodeStringToAnsiString(&AnsiString, &ValueData, FALSE);
+	    }

 	  Length = Length / sizeof(WCHAR);
 	}
       else
 	{
 	  Length = min(*lpcbData, Length);

-	  RtlMoveMemory(lpData, ValueData.Buffer, Length);

+	  if (ErrorCode == ERROR_SUCCESS && ValueData.Buffer != NULL)
+	    {
+	      RtlMoveMemory(lpData, ValueData.Buffer, Length);
+	    }

 	}

-    }

-  if (lpcbData != NULL)
-    {
-      *lpcbData = Length;

+      if (lpcbData != NULL)
+	{
+	  *lpcbData = Length;
+	}

     }
 

-  if (ValueData.Buffer)

+  if (ValueData.Buffer != NULL)

     {
       RtlFreeHeap(ProcessHeap, 0, ValueData.Buffer);
     }