Don't join in Stop methods. THe decode and analysis thread may never get woken up from packetqueue. Leave it for the destructor.

src/zm_decoder_thread.cpp

@@ -10,6 +10,7 @@ DecoderThread::DecoderThread(Monitor *monitor) :
 
 DecoderThread::~DecoderThread() {
   Stop();
+  if (thread_.joinable()) thread_.join();
 }
 
 void DecoderThread::Start() {
@@ -20,7 +21,6 @@ void DecoderThread::Start() {
 
 void DecoderThread::Stop() {
   terminate_ = true;
-  if (thread_.joinable()) thread_.join();
 }
 
 void DecoderThread::Run() {