From dd5406249694408fd355dc7456ff4c1ba6f9f903 Mon Sep 17 00:00:00 2001
From: Jeff Hill <johill@lanl.gov>
Date: Fri, 13 Mar 2009 17:23:07 +0000
Subject: [PATCH] fixed mantis 336 - timer queue should have try / catch block
 around call to user's expiration callback

---
 src/libCom/timer/timerPrivate.h |  8 ++++++
 src/libCom/timer/timerQueue.cpp | 46 ++++++++++++++++++++++++++++++---
 2 files changed, 50 insertions(+), 4 deletions(-)

diff --git a/src/libCom/timer/timerPrivate.h b/src/libCom/timer/timerPrivate.h
index cd6689ca3..6760d1bf2 100644
--- a/src/libCom/timer/timerPrivate.h
+++ b/src/libCom/timer/timerPrivate.h
@@ -18,6 +18,8 @@
 #ifndef epicsTimerPrivate_h
 #define epicsTimerPrivate_h
 
+#include <typeinfo>
+
 #include "tsFreeList.h"
 #include "epicsSingleton.h"
 #include "tsDLList.h"
@@ -86,6 +88,8 @@ private:
     friend class timerQueue;
 };
 
+using std :: type_info;
+
 class timerQueue : public epicsTimerQueue {
 public:
     timerQueue ( epicsTimerQueueNotify &notify );
@@ -103,7 +107,11 @@ private:
     epicsTimerQueueNotify & notify;
     timer * pExpireTmr;
     epicsThreadId processThread;
+    epicsTime exceptMsgTimeStamp;
     bool cancelPending;
+    static const double exceptMsgMinPeriod;
+    void printExceptMsg ( const char * pName, 
+                const type_info & type );
 	timerQueue ( const timerQueue & );
     timerQueue & operator = ( const timerQueue & );
     friend class timer;
diff --git a/src/libCom/timer/timerQueue.cpp b/src/libCom/timer/timerQueue.cpp
index 911faf4b0..548300307 100644
--- a/src/libCom/timer/timerQueue.cpp
+++ b/src/libCom/timer/timerQueue.cpp
@@ -19,12 +19,19 @@
 #define epicsExportSharedSymbols
 #include "epicsGuard.h"
 #include "timerPrivate.h"
+#include "errlog.h"
+
+const double timerQueue :: exceptMsgMinPeriod = 60.0 * 5.0; // seconds
 
 epicsTimerQueue::~epicsTimerQueue () {}
 
 timerQueue::timerQueue ( epicsTimerQueueNotify & notifyIn ) :
-    notify ( notifyIn ), pExpireTmr ( 0 ),  
-    processThread ( 0 ), cancelPending ( false )
+    notify ( notifyIn ), 
+    pExpireTmr ( 0 ),  
+    processThread ( 0 ), 
+    exceptMsgTimeStamp ( 
+        epicsTime :: getCurrent () - exceptMsgMinPeriod ),
+    cancelPending ( false )
 {
 }
 
@@ -36,6 +43,30 @@ timerQueue::~timerQueue ()
     }
 }
 
+void timerQueue ::
+    printExceptMsg ( const char * pName, const type_info & type )
+{
+    epicsTime cur = epicsTime :: getCurrent ();
+    double delay = cur - this->exceptMsgTimeStamp;
+    if ( delay >= exceptMsgMinPeriod ) {
+        this->exceptMsgTimeStamp = cur;
+        char date[64];
+        cur.strftime ( date, sizeof ( date ), 
+                        "%a %b %d %Y %H:%M:%S.%f" );
+        // we dont touch the typeid for the timer expiration
+        // notify interface here because they might have 
+        // destroyed the timer during its callback
+        errlogPrintf ( 
+            "timerQueue: Unexpected C++ exception \"%s\" "
+            "with type \"%s\" during timer expiration "
+            "callback at %s\n",
+            pName, 
+            type.name (), 
+            date );
+        errlogFlush ();
+    }
+}
+
 double timerQueue::process ( const epicsTime & currentTime )
 {  
     epicsGuard < epicsMutex > guard ( this->mutex );
@@ -96,8 +127,15 @@ double timerQueue::process ( const epicsTime & currentTime )
             debugPrintf ( ( "%5u expired \"%s\" with error %f sec\n", 
                 N++, typeid ( this->pExpireTmr->notify ).name (), 
                 currentTime - this->pExpireTmr->exp ) );
-
-            expStat = pTmpNotify->expire ( currentTime );
+            try {
+                expStat = pTmpNotify->expire ( currentTime );
+            }
+            catch ( std::exception & except ) {
+                printExceptMsg ( except.what (), typeid ( except ) );
+            }
+            catch ( ... ) {
+                printExceptMsg ( "non-standard exception", typeid ( void ) );
+            }
         }
 
         //