Compares list of categories on the old_contact
with the list of categories on the new_contact
and fills
out_added
categories and out_removed
categories accordingly, as if the old_contact
is replaced with the
new_contact
.
When either of the contacts is null
, it's considered as having no categories set. Rather than returning empty
GenericSet, the return argument is set to null
when there are no added/removed categories.
The key of the hash table is the category string, the value is an integer (1). There is used the hash table only for speed.
The returned GenericSet-s should be freed with g_hash_table_unref
, when no longer needed.
old_contact |
an old Contact, or |
new_contact |
a new Contact, or |
out_added |
a GenericSet with added categories |
out_removed |
a GenericSet with removed categories |