Make LiveTVChain a reference counted object

Under some circumstances, the LiveTVChain instance could have been deleted by the backend MainServer, yet would continue to be used by TVRec. I'm no fan of reference counted objects, it's only a workaround over an architecture problem, but at this stage; it's the easiest fix Fixes #11661
MythTV · Jul 11, 2013 · 93488a2 · 93488a2
1 parent 6749fee
commit 93488a2
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Showing 5 changed files with 14 additions and 4 deletions.
diff --git a/mythtv/libs/libmythtv/livetvchain.cpp b/mythtv/libs/libmythtv/livetvchain.cpp
@@ -23,16 +23,18 @@ static inline void clear(LiveTVChainEntry &entry)
 /** \class LiveTVChain
  *  \brief Keeps track of recordings in a current LiveTV instance
  */
-LiveTVChain::LiveTVChain() :
+LiveTVChain::LiveTVChain() : ReferenceCounter("LiveTVChain"),
     m_id(""), m_maxpos(0), m_lock(QMutex::Recursive),
     m_curpos(0), m_cur_chanid(0),
     m_switchid(-1), m_jumppos(0)
 {
     clear(m_switchentry);
+    LOG(VB_GENERAL, LOG_DEBUG, LOC + "ctor");
 }
 
 LiveTVChain::~LiveTVChain()
 {
+    LOG(VB_GENERAL, LOG_DEBUG, LOC + "dtor");
 }
 
 QString LiveTVChain::InitializeNewChain(const QString &seed)

diff --git a/mythtv/libs/libmythtv/livetvchain.h b/mythtv/libs/libmythtv/livetvchain.h
@@ -8,6 +8,8 @@
 #include <QList>
 
 #include "mythtvexp.h"
+#include "referencecounter.h"
+
 
 class ProgramInfo;
 class MythSocket;
@@ -24,7 +26,7 @@ struct MTV_PUBLIC LiveTVChainEntry
     QString inputname;
 };
 
-class MTV_PUBLIC LiveTVChain
+class MTV_PUBLIC LiveTVChain : public ReferenceCounter
 {
   public:
     LiveTVChain();

diff --git a/mythtv/libs/libmythtv/playercontext.cpp b/mythtv/libs/libmythtv/playercontext.cpp
@@ -822,7 +822,7 @@ void PlayerContext::SetTVChain(LiveTVChain *chain)
     if (tvchain)
     {
         tvchain->DestroyChain();
-        delete tvchain;
+        tvchain->DecrRef();
         tvchain = NULL;
     }
 

diff --git a/mythtv/libs/libmythtv/tv_rec.cpp b/mythtv/libs/libmythtv/tv_rec.cpp
@@ -588,6 +588,7 @@ RecStatusType TVRec::StartRecording(const ProgramInfo *pginfo)
             QString message = QString("LIVETV_EXITED");
             MythEvent me(message, tvchain->GetID());
             gCoreContext->dispatch(me);
+            tvchain->DecrRef();
             tvchain = NULL;
         }
 
@@ -2605,6 +2606,7 @@ void TVRec::SpawnLiveTV(LiveTVChain *newchain, bool pip, QString startchan)
     QMutexLocker lock(&stateChangeLock);
 
     tvchain = newchain;
+    tvchain->IncrRef(); // mark it for TVRec use
     tvchain->ReloadAll();
 
     QString hostprefix = gCoreContext->GenMythURL(
@@ -2862,6 +2864,10 @@ void TVRec::StopLiveTV(void)
     WaitForEventThreadSleep();
 
     // We are done with the tvchain...
+    if (tvchain)
+    {
+        tvchain->DecrRef();
+    }
     tvchain = NULL;
 }
 

diff --git a/mythtv/programs/mythbackend/mainserver.cpp b/mythtv/programs/mythbackend/mainserver.cpp
@@ -6089,7 +6089,7 @@ void MainServer::DeleteChain(LiveTVChain *chain)
     }
     liveTVChains = newChains;
 
-    delete chain;
+    chain->DecrRef();
 }
 
 void MainServer::SetExitCode(int exitCode, bool closeApplication)