dovecot: When converting sequence ranges to UID ranges, don't tr...

[dovecot at dovecot.org]

details:   http://hg.dovecot.org/dovecot/rev/e0115302e68e
changeset: 7133:e0115302e68e
user:      Timo Sirainen <tss at iki.fi>
date:      Mon Jan 07 07:37:12 2008 +0200
description:
When converting sequence ranges to UID ranges, don't try to optimize the UID
ranges by letting them contain expunged UIDs. This makes the transactions
somewhat larger if UID range has holes, but it properly fixes problems with
updating flags for expunged messages.

diffstat:

1 file changed, 79 insertions(+), 46 deletions(-)
src/lib-index/mail-index-transaction.c |  125 ++++++++++++++++++++------------

diffs (162 lines):

diff -r a1d1f7c9671e -r e0115302e68e src/lib-index/mail-index-transaction.c
--- a/src/lib-index/mail-index-transaction.c	Mon Jan 07 07:34:08 2008 +0200
+++ b/src/lib-index/mail-index-transaction.c	Mon Jan 07 07:37:12 2008 +0200
@@ -196,44 +196,87 @@ static bool mail_index_seq_array_add(ARR
 	}
 }
 
+static uint32_t
+mail_index_transaction_get_uid(struct mail_index_transaction *t, uint32_t seq)
+{
+	const struct mail_index_record *rec;
+
+	i_assert(seq > 0);
+
+	if (seq >= t->first_new_seq)
+		rec = mail_index_transaction_lookup(t, seq);
+	else {
+		i_assert(seq <= t->view->map->hdr.messages_count);
+		rec = MAIL_INDEX_MAP_IDX(t->view->map, seq - 1);
+	}
+	i_assert(rec->uid != 0);
+	return rec->uid;
+}
+
 static void
-mail_index_buffer_convert_to_uids(struct mail_index_transaction *t,
-				  ARRAY_TYPE(seq_array) *array, bool range)
-{
-        struct mail_index_view *view = t->view;
-	const struct mail_index_record *rec;
+mail_index_convert_to_uids(struct mail_index_transaction *t,
+			   ARRAY_TYPE(seq_array) *array)
+{
 	uint32_t *seq;
-	unsigned int i, j, count, range_count;
+	unsigned int i, count;
 
 	if (!array_is_created(array))
 		return;
 
 	count = array_count(array);
-	range_count = range ? 1 : 0;
 	for (i = 0; i < count; i++) {
 		seq = array_idx_modifiable(array, i);
-
-		for (j = 0; j <= range_count; j++, seq++) {
-			i_assert(*seq > 0);
-
-			if (*seq >= t->first_new_seq)
-				rec = mail_index_transaction_lookup(t, *seq);
-			else {
-				i_assert(*seq <= view->map->hdr.messages_count);
-				rec = MAIL_INDEX_MAP_IDX(view->map, *seq - 1);
-			}
-
-			/* we're using only rec->uid, no need to bother locking
-			   the index. */
-			if (rec->uid == 0) {
-				/* FIXME: replace with simple assert once we
-				   figure out why this happens.. */
-				i_panic("seq = %u, rec->uid = %u, "
-					"first_new_seq = %u, messages = %u",
-					*seq, rec->uid, t->first_new_seq,
-					view->map->hdr.messages_count);
-			}
-			*seq = rec->uid;
+		*seq = mail_index_transaction_get_uid(t, *seq);
+	}
+}
+
+static uint32_t
+get_nonexpunged_uid2(struct mail_index_transaction *t,
+		     uint32_t uid1, uint32_t seq1)
+{
+	seq1++;
+
+	while (mail_index_transaction_get_uid(t, seq1) == uid1 + 1) {
+		seq1++;
+		uid1++;
+	}
+	return uid1;
+}
+
+static void
+mail_index_convert_to_uid_ranges(struct mail_index_transaction *t,
+				 ARRAY_TYPE(seq_range) *array)
+{
+	struct seq_range *range, *new_range;
+	unsigned int i, count;
+	uint32_t uid1, uid2;
+
+	if (!array_is_created(array))
+		return;
+
+	count = array_count(array);
+	for (i = 0; i < count; i++) {
+		range = array_idx_modifiable(array, i);
+
+		uid1 = mail_index_transaction_get_uid(t, range->seq1);
+		uid2 = mail_index_transaction_get_uid(t, range->seq2);
+		if (uid2 - uid1 == range->seq2 - range->seq1) {
+			/* simple conversion */
+			range->seq1 = uid1;
+			range->seq2 = uid2;
+		} else {
+			/* remove expunged UIDs */
+			new_range = array_insert_space(array, i);
+			range = array_idx_modifiable(array, i + 1);
+			count++;
+
+			memcpy(new_range, range, array->arr.element_size);
+			new_range->seq1 = uid1;
+			new_range->seq2 = get_nonexpunged_uid2(t, uid1,
+							       range->seq1);
+
+			/* continue the range without the inserted seqs */
+			range->seq1 += new_range->seq2 - new_range->seq1 + 1;
 		}
 	}
 }
@@ -248,14 +291,8 @@ static void keyword_updates_convert_to_u
 
 	updates = array_get_modifiable(&t->keyword_updates, &count);
 	for (i = 0; i < count; i++) {
-		if (array_is_created(&updates[i].add_seq)) {
-			mail_index_buffer_convert_to_uids(t,
-				(void *)&updates[i].add_seq, TRUE);
-		}
-		if (array_is_created(&updates[i].remove_seq)) {
-			mail_index_buffer_convert_to_uids(t,
-				(void *)&updates[i].remove_seq, TRUE);
-		}
+		mail_index_convert_to_uid_ranges(t, &updates[i].add_seq);
+		mail_index_convert_to_uid_ranges(t, &updates[i].remove_seq);
 	}
 }
 
@@ -267,19 +304,15 @@ mail_index_transaction_convert_to_uids(s
 
 	if (array_is_created(&t->ext_rec_updates)) {
 		updates = array_get_modifiable(&t->ext_rec_updates, &count);
-		for (i = 0; i < count; i++) {
-			if (!array_is_created(&updates[i]))
-				continue;
-			mail_index_buffer_convert_to_uids(t, &updates[i],
-							  FALSE);
-		}
+		for (i = 0; i < count; i++)
+			mail_index_convert_to_uids(t, (void *)&updates[i]);
 	}
 
         keyword_updates_convert_to_uids(t);
 
-	mail_index_buffer_convert_to_uids(t, (void *)&t->expunges, TRUE);
-	mail_index_buffer_convert_to_uids(t, (void *)&t->updates, TRUE);
-	mail_index_buffer_convert_to_uids(t, (void *)&t->keyword_resets, TRUE);
+	mail_index_convert_to_uid_ranges(t, &t->expunges);
+	mail_index_convert_to_uid_ranges(t, (void *)&t->updates);
+	mail_index_convert_to_uid_ranges(t, &t->keyword_resets);
 	return 0;
 }