DefineDosDeviceW: implemented the DDD_REMOVE_DEFINITION flag.

dlls/kernel/volume.c

@@ -936,6 +936,8 @@ BOOL WINAPI DefineDosDeviceW( DWORD flags, LPCWSTR devname, LPCWSTR targetpath )
     BOOL ret = FALSE;
     char *path = NULL, *target, *p;
 
+    if (!(flags & DDD_REMOVE_DEFINITION))
+    {
         if (!(flags & DDD_RAW_TARGET_PATH))
         {
             FIXME( "(0x%08lx,%s,%s) DDD_RAW_TARGET_PATH flag not set, not supported yet\n",
@@ -955,6 +957,8 @@ BOOL WINAPI DefineDosDeviceW( DWORD flags, LPCWSTR devname, LPCWSTR targetpath )
             SetLastError( ERROR_NOT_ENOUGH_MEMORY );
             return FALSE;
         }
+    }
+    else target = NULL;
 
     /* first check for a DOS device */
 
@@ -974,13 +978,22 @@ BOOL WINAPI DefineDosDeviceW( DWORD flags, LPCWSTR devname, LPCWSTR targetpath )
 
     if (path)
     {
+        if (target)
+        {
             TRACE( "creating symlink %s -> %s\n", path, target );
             unlink( path );
             if (!symlink( target, path )) ret = TRUE;
             else FILE_SetDosError();
+        }
+        else
+        {
+            TRACE( "removing symlink %s\n", path );
+            if (!unlink( path )) ret = TRUE;
+            else FILE_SetDosError();
+        }
         HeapFree( GetProcessHeap(), 0, path );
     }
-    HeapFree( GetProcessHeap(), 0, target );
+    if (target) HeapFree( GetProcessHeap(), 0, target );
     return ret;
 }