[Patch] Allow access to /proc/registry/HKEY_PERFORMANCE_DATA

Christian Franke Christian.Franke@t-online.de
Fri Dec 19 17:36:00 GMT 2008

Chris January wrote:
> On Fri, Dec 19, 2008 at 1:58 PM, Christian Franke  wrote:
>>        (fhandler_registry::fill_filebuf): Use larger buffer to speed up
>>        access to HKEY_PERFORMANCE_DATA values.  Remove check for possible
>>        subkey.  Add RegCloseKey ().
> +      /* RegQueryValueEx () opens HKEY_PERFORMANCE_DATA.  */
> +      RegCloseKey (handle);
> I'm slightly puzzled by this change. handle is usually closed in
> fhandler_register::close. If you close it here then won't CloseHandle
> be called with an invalid handle in that method?

fhandler_registry::close() closes only handles < HKEY_CLASSES_ROOT. 
Normally, it is not necessary to close predefined keys.

HKEY_PERFORMANCE_DATA is an exception: It has no subkeys and access to a 
value opens the predefined key. Therefore, the key is closed immediately 
after value access. Doing this in close() would require to pass a new 
'key_is_open' flag from fill_filebuf().


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