The keyframe cached for late joiners survived Monitor::Close(). A
consumer connecting while the camera reconnected was primed with a
keyframe from the previous capture session, whose pts can be ahead of
what the new session produces, and with identical stream parameters
there is no generation bump to warn it. Add StreamSocket::InvalidateKeyframe()
and call it from Close(); the next keyframe from the new session fills
the cache again.
Tests: after InvalidateKeyframe() a new consumer gets HELLO and then the
next live packet, with no KEYFRAME replay in between.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Add SendMonitorEvent() to broadcast an EVENT frame to every connected
consumer, framed with a per-monitor event sequence (independent of the
media sequences, so it is not reset by a media generation bump) and the
current media generation for correlation. Events are control messages and
are never dropped from a client queue; the sequence still advances when no
consumer is connected, so a late joiner sees the loss as a gap.
Add SetSnapshotEvent() to cache the current-status snapshot replayed to
each new consumer on connect, the events analogue of the cached keyframe.
AcceptClient now enqueues HELLO(s), the snapshot, then the keyframe.
Tests: a broadcast EVENT round-trips with the right type/stream/sequence;
the event sequence advances across a clientless gap; the snapshot is
replayed after HELLO on connect. Ran ./tests/tests '[stream_socket]':
130 assertions in 11 cases pass.
refs #2875
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Per-monitor media stream server for the wire protocol added previously:
a poll()-driven listener thread serving multiple consumers at once over
PATH_SOCKS/stream_{monitor_id}.sock.
Memory and blocking behaviour:
- each message is serialized once and shared across all client queues;
media payloads are reference-counted via av_packet_clone, no copies
- header and payload are written with writev, never concatenated
- the producer (capture thread) never blocks: per-client queues are
bounded by bytes and message count; on overflow the oldest non-control
messages are dropped for that client only, observable as sequence gaps
and in STATS; clients making no progress are disconnected
- the latest keyframe access unit is cached (refcount only) and replayed
to late joiners after HELLO for immediate first-frame rendering
Parameter changes (SetVideoParams/SetAudioParams) bump the generation,
reset sequences and rebroadcast HELLO. Peers are checked via SO_PEERCRED
against ZM_STREAM_SOCKET_ALLOWED_UIDS; sockets are chmod 0660 with group
ZM_STREAM_SOCKET_GROUP. Stop() sends BYE so consumers can distinguish
shutdown from failure.
Tests: 8 new Catch2 test cases (lifecycle/permissions, HELLO-first
ordering, late-joiner keyframe replay, queue overflow with sequence-gap
and STATS accounting, stalled-vs-live client isolation, generation bump,
BYE on stop, allowed-uids parsing). Full suite: 98/98 pass via ctest.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
