- make it thread-safe

1 files changed, 11 insertions, 2 deletions

diff --git a/noncore/multimedia/opieplayer2/singleton.h b/noncore/multimedia/opieplayer2/singleton.h
index 83e228f..825344e 100644
--- a/noncore/multimedia/opieplayer2/singleton.h
+++ b/noncore/multimedia/opieplayer2/singleton.h
@@ -17,12 +17,14 @@
    Boston, MA 02111-1307, USA.
 */
 
 #ifndef SINGLETON_H
 #define SINGLETON_H
 
+#include "threadutil.h"
+
 template <class Product>
 struct DefaultSingletonCreator
 {
     static Product *create() { return new Product; }
 };
 
@@ -39,14 +41,17 @@ template
 >
 class Singleton
 {
 public:
     static T &self()
     {
-        if ( !s_self )
-            s_self = Creator<T>::create();
+        if ( !s_self ) {
+            ThreadUtil::AutoLock lock( s_guard );
+            if ( !s_self )
+                s_self = Creator<T>::create();
+        }
         return *s_self;
     }
 
 protected:
     Singleton()
     { s_self = static_cast<T *>( this ); }
@@ -55,14 +60,18 @@ protected:
 
 private:
     Singleton( const Singleton<T, Creator> &rhs );
     Singleton<T, Creator> &operator=( const Singleton<T, Creator> &rhs );
 
     static T *s_self;
+    static ThreadUtil::Mutex s_guard;
 };
 
 template <class T, template <class> class Creator>
 T *Singleton<T, Creator>::s_self = 0;
 
+template <class T, template <class> class Creator>
+ThreadUtil::Mutex Singleton<T, Creator>::s_guard;
+
 #endif // SINGLETON_H
 /* vim: et sw=4 ts=4
  */