id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc	mlocked
10067	Potential memory leak in EITHelper	mythtv@…	Stuart Auchterlonie	"In EITHelper.cpp - EITHelper keeps a list of incomplete_events, and unmatched_etts. If for some reason when parsing the EIT and ETT tables, it does not manage to match any ETT to an EIT entry, the unmatched item will remain on the list indefinitely.

incomplete_events stores character strings allocated with new. If the EITHelper is destroyed, those will be unreferenced and simply leaked.

If EITHelper is not destroyed, incomplete_events and unmatched_etts can grow without bounds. Aside from the memory consumption, that has another unwanted side effect that leftover unmatched items from earlier calls can be picked up as incorrect matches on later calls. This will result in program descriptions being updated with descriptions from other shows - a behavior I'm seeing, which is the whole reason I started looking at EITHelper.

Evidence of the leak can be seen by turning on verbose logging for EIT and watching for this log message:
{{{
        VERBOSE(VB_EIT, LOC +
                QString(""Added %1 events -- complete(%2) ""
                        ""incomplete(%3) unmatched(%4)"")
                .arg(insertCount).arg(db_events.size())
                .arg(incomplete_events.size()).arg(unmatched_etts.size()));
}}}


In the same method, there is a logic bug when iterating over events. The for loop compares the index with the size of the db_events queue, but at the same time the loops is removing events. Thus the index is incremented and the size is decreased, so the loop will always end with only half of the events processed.

So this:
{{{
    for (uint i = 0; (i < kChunkSize) && (i < db_events.size()); i++)
    {
        DBEventEIT *event = db_events.dequeue();
}}}

should become this:
{{{
    for (uint i = 0; (i < kChunkSize) && (db_events.size() > 0); i++)
    {
        DBEventEIT *event = db_events.dequeue();
}}}

I don't think an ETT table from one event can legitimately be related to an EIT from a different event, so I believe after each iteration of that loop, incomplete_events and unmatched_etts should be cleared - taking care to free the memory associated with items stored in incomplete_events.
}}}"	Patch - Bug Fix	closed	minor	0.28	MythTV - EIT	Master Head	medium	Fixed			0