Re: bug in ext_attributes or my xml file?

[Hans Breuer <hans breuer org>]

Am 17.06.2008 15:26, Avijit Ghosh schrieb:
> I think I just figured it out. The way copy / paste works with instances
> leads to this behavior. When you drag a new instance from the shape library
> creates the new memory. However if you select / paste it seems to be copying
> references to the data which accidentally glues them together. If you save
> the file and then reload it the instances become separate so this is
> obviously a bug. 
Your analysis looks pretty valid and is consisten with the my 
interpretation of the code in objects/custom/custom_object.c(custom_copy),
specifically line 1651 ff:

  if (custom->info->ext_attr_size) /* copy ext area past end */
    memcpy (newcustom + 1, custom + 1, custom->info->ext_attr_size);

assumes every extended atrribute is stored by value, for strings it is just 
copying the pointer thus 'glueing' the values together. If these copied 
properties would be modified after the copy it should even crash ;(

> I can go in and fix this if it hasn't been fixed already.
Patches are appreciated, may it can be fixed by delegating part of 
custom_copy to object_copy_using_properties().

Even if you do not fix the issue please it with a complete enogh example to 
reproduce in bugzilla.

Thanks,
        Hans

-------- Hans "at" Breuer "dot" Org -----------
Tell me what you need, and I'll tell you how to
get along without it.                -- Dilbert