From ae90ebf74f51a61967f87bc70daa1193dbeb1492 Mon Sep 17 00:00:00 2001
From: Isaac Connor <isaac@zoneminder.com>
Date: Sun, 13 Jun 2021 14:04:40 -0400
Subject: [PATCH] Return early if packetqueue is empty instead of getting the
 lock.  Return early in clear() if we are not initialised

---
 src/zm_packetqueue.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/zm_packetqueue.cpp b/src/zm_packetqueue.cpp
index 9662e4958..b18fdc266 100644
--- a/src/zm_packetqueue.cpp
+++ b/src/zm_packetqueue.cpp
@@ -179,6 +179,7 @@ void PacketQueue::clearPackets(const std::shared_ptr<ZMPacket> &add_packet) {
   // So start at the beginning, counting video packets until the next keyframe.  
   // Then if deleting those packets doesn't break 1 and 2, then go ahead and delete them.
   if (deleting) return;
+  if (!pktQueue.size()) return;
 
   if (keep_keyframes and ! (
         add_packet->packet.stream_index == video_stream_id
@@ -197,7 +198,6 @@ void PacketQueue::clearPackets(const std::shared_ptr<ZMPacket> &add_packet) {
     return;
   }
   std::unique_lock<std::mutex> lck(mutex);
-  if (!pktQueue.size()) return;
 
   // If analysis_it isn't at the end, we need to keep that many additional packets
   int tail_count = 0;
@@ -325,6 +325,8 @@ void PacketQueue::clearPackets(const std::shared_ptr<ZMPacket> &add_packet) {
 void PacketQueue::clear() {
   deleting = true;
   condition.notify_all();
+  if (!packet_counts) // special case, not initialised
+    return;
   Debug(1, "Clearing packetqueue");
   std::unique_lock<std::mutex> lck(mutex);