- RtlSetEnvironmentVariable: Removing a variable that didn't exist in the first place should still returns STATUS_SUCCESS.

- Removing a variable can be done by using a pointer to a UNICODE_STRING with a NULL Buffer as the value, as well as just passing NULL as the value.

svn path=/trunk/; revision=40470

reactos/dll/win32/kernel32/misc/env.c

@@ -244,21 +244,12 @@ SetEnvironmentVariableW (
 	RtlInitUnicodeString (&VarName,
 	                      lpName);
 
-	if (lpValue)
-	{
-		RtlInitUnicodeString (&VarValue,
-		                      lpValue);
+	RtlInitUnicodeString (&VarValue,
+	                      lpValue);
 
-		Status = RtlSetEnvironmentVariable (NULL,
-		                                    &VarName,
-		                                    &VarValue);
-	}
-	else
-	{
-		Status = RtlSetEnvironmentVariable (NULL,
-		                                    &VarName,
-		                                    NULL);
-	}
+	Status = RtlSetEnvironmentVariable (NULL,
+	                                    &VarName,
+	                                    &VarValue);
 
 	if (!NT_SUCCESS(Status))
 	{

reactos/lib/rtl/env.c

@@ -354,7 +354,7 @@ RtlSetEnvironmentVariable(PWSTR *Environment,
    }
 
 found:
-   if (Value != NULL)
+   if (Value != NULL && Value->Buffer != NULL)
    {
       hole_len = tail - hole;
       /* calculate new environment size */
@@ -473,10 +473,6 @@ found:
                  tail,
                  (env_end - tail) * sizeof(WCHAR));
       }
-      else
-      {
-         Status = STATUS_VARIABLE_NOT_FOUND;
-      }
    }
 
    if (Environment == NULL)