/* CLAWS subject threading:
- in the first round it inserts subject lines in a hash
- table. a duplicate subject line replaces the one in
- the table only if its older. (this round should actually
- create a list of all duplicate subject lines)
+ in the first round it inserts subject lines in a
+ relation (subject <-> node)
the second round finishes the threads by attaching
- duplicate subject lines to the one found in the
- hash table. as soon as a subject line is found that
- is too old, that one becomes the new parent for
- the next iteration. (this fails when a parent arrived
- later than its child.)
+ matching subject lines to the one found in the
+ relation. will use the oldest node with the same
+ subject that is not more then thread_by_subject_max_age
+ days old (see subject_relation_lookup)
*/
static void subject_relation_insert(GRelation *relation, GNode *node)