Add mutex protection on the db logging queue

Just to be sure. QQueue isn't threadsafe. Why play with fire?
MythTV · May 29, 2011 · d3675b5 · d3675b5
1 parent a6e9e5e
commit d3675b5
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diff --git a/mythtv/libs/libmythbase/mythlogging.cpp b/mythtv/libs/libmythbase/mythlogging.cpp
@@ -314,24 +314,32 @@ void DBLoggerThread::run(void)
 
     aborted = false;
 
+    QMutexLocker qLock(&m_queueMutex);
+
     while(!aborted || !m_queue->isEmpty())
     {
         if (m_queue->isEmpty())
         {
+            qLock.unlock();
             msleep(100);
+            qLock.relock();
             continue;
         }
 
         item = m_queue->dequeue();
         if (!item)
             continue;
 
+        qLock.unlock();
+
         if( item->message && !aborted )
         {
             m_logger->logqmsg(item);
         }
 
         deleteItem(item);
+
+        qLock.relock();
     }
 }
 

diff --git a/mythtv/libs/libmythbase/mythlogging.h b/mythtv/libs/libmythbase/mythlogging.h
@@ -5,6 +5,8 @@
 #include <QString>
 #include <QThread>
 #include <QQueue>
+#include <QMutex>
+#include <QMutexLocker>
 #endif
 #include <stdint.h>
 #include <time.h>
@@ -175,11 +177,13 @@ class DBLoggerThread : public QThread {
         void stop(void) { aborted = true; }
         bool enqueue(LoggingItem_t *item) 
         { 
+            QMutexLocker qLock(&m_queueMutex); 
             m_queue->enqueue(item); 
             return true; 
         }
     private:
         DatabaseLogger *m_logger;
+        QMutex m_queueMutex;
         QQueue<LoggingItem_t *> *m_queue;
         bool aborted;
 };