+ term = g_strdup_printf ("%s%s", find_prefix (prefix_name), value);
+
+ *begin = db.postlist_begin (term);
+
+ if (end)
+ *end = db.postlist_end (term);
+
+ free (term);
+}
+
+Xapian::Document
+find_message_by_docid (Xapian::Database db, Xapian::docid docid)
+{
+ return db.get_document (docid);
+}
+
+Xapian::Document
+find_message_by_message_id (Xapian::Database db, const char *message_id)
+{
+ Xapian::PostingIterator i, end;
+
+ find_messages_by_term (db, "msgid", message_id, &i, &end);
+
+ if (i != end)
+ return find_message_by_docid (db, *i);
+ else
+ return Xapian::Document ();
+}
+
+static void
+insert_thread_id (GHashTable *thread_ids, Xapian::Document doc)
+{
+ string value_string;
+ const char *value;
+
+ value_string = doc.get_value (NOTMUCH_VALUE_THREAD);
+ value = value_string.c_str();
+ if (strlen (value))
+ g_hash_table_insert (thread_ids, strdup (value), NULL);
+}
+
+static char *
+find_thread_id (Xapian::Database db,
+ GPtrArray *parents,
+ const char *message_id)
+{
+ Xapian::PostingIterator child, children_end;
+ Xapian::Document doc;
+ GHashTable *thread_ids;
+ GList *keys, *l;
+ GString *result = NULL;
+ unsigned int i;
+ const char *parent_message_id;
+
+ thread_ids = g_hash_table_new (g_str_hash, g_str_equal);
+
+ find_messages_by_term (db, "ref", message_id, &child, &children_end);
+ for ( ; child != children_end; child++) {
+ doc = find_message_by_docid (db, *child);
+ insert_thread_id (thread_ids, doc);