- backporting two changes from qt3:

  - added QInterfacePtr template class to take over the tedious work
    of manual refcounting on interface objects
  - the QREFCOUNT macro no longer relies on the developer to declare
    (and initialize!) a refcnt variable but defines a qtrefcount class
    variable itself, that takes care of proper initialization
    (fixes various missing refcounter initializations found)

Harlekin suggested to commit :)

1 files changed, 89 insertions, 1 deletions

diff --git a/library/qcom.h b/library/qcom.h
index 8c0fa60..9972d8f 100644
--- a/library/qcom.h
+++ b/library/qcom.h
@@ -54,30 +54,118 @@ struct Q_EXPORT QUnknownInterface
 #define IID_QLibrary QUuid( 0xd16111d4, 0xe1e7, 0x4c47, 0x85, 0x99, 0x24, 0x48, 0x3d, 0xae, 0x2e, 0x07)
 #endif
  
 struct Q_EXPORT QLibraryInterface : public QUnknownInterface
 {
     virtual bool    init() = 0;
     virtual void    cleanup() = 0;
     virtual bool    canUnload() const = 0;
 };
 
 #define Q_CREATE_INSTANCE( IMPLEMENTATION )         \
         IMPLEMENTATION *i = new IMPLEMENTATION; \
         QUnknownInterface* iface = 0;                   \
         i->queryInterface( IID_QUnknown, &iface );      \
         return iface;
 
+template <class T>
+class QInterfacePtr
+{
+public:
+    QInterfacePtr():iface(0){}
+
+    QInterfacePtr( T* i) {
+        if ( (iface = i) )
+            iface->addRef();
+    }
+
+    QInterfacePtr(const QInterfacePtr<T> &p) {
+        if ( (iface = p.iface) )
+            iface->addRef();
+    }
+
+    ~QInterfacePtr() {
+        if ( iface )
+            iface->release();
+    }
+
+    QInterfacePtr<T> &operator=(const QInterfacePtr<T> &p) {
+        if ( iface != p.iface ) {
+            if ( iface )
+                iface->release();
+            if ( (iface = p.iface) )
+                iface->addRef();
+        }
+        return *this;
+    }
+
+    QInterfacePtr<T> &operator=(T* i) {
+        if (iface != i ) {
+            if ( iface )
+                iface->release();
+            if ( (iface = i) )
+                iface->addRef();
+        }
+        return *this;
+    }
+
+    bool operator==( const QInterfacePtr<T> &p ) const { return iface == p.iface; }
+
+    bool operator!= ( const QInterfacePtr<T>& p ) const {  return !( *this == p ); }
+
+    bool isNull() const { return !iface; }
+
+    T* operator->() const { return iface; }
+
+    T& operator*() const { return *iface; }
+
+    operator T*() const { return iface; }
+
+    QUnknownInterface** operator &() const {
+        if( iface )
+            iface->release();
+        return (QUnknownInterface**)&iface;
+    }
+
+    T** operator &() {
+        if ( iface )
+            iface->release();
+        return &iface;
+    }
+
+private:
+    T* iface;
+};
+
+
+// internal class that wraps an initialized ulong
+struct Q_EXPORT QtULong
+{
+    QtULong() : ref( 0 ) { }
+    operator unsigned long () const { return ref; }
+    unsigned long& operator++() { return ++ref; }
+    unsigned long operator++( int ) { return ref++; }
+    unsigned long& operator--() { return --ref; }
+    unsigned long operator--( int ) { return ref--; }
+
+    unsigned long ref;
+};
+
 #define Q_EXPORT_INTERFACE() \
         extern "C" QUnknownInterface* ucm_instantiate()
 
-#define Q_REFCOUNT  ulong addRef() {return ref++;}ulong release() {if(!--ref){delete this;return 0;}return ref;}
+#define Q_REFCOUNT \
+private:          \
+    QtULong qtrefcount;   \
+public:          \
+    ulong addRef() {return qtrefcount++;} \
+    ulong release() {if(!--qtrefcount){delete this;return 0;}return qtrefcount;}
 
 #else // QT_NO_COMPONENT
 
 struct Q_EXPORT QUnknownInterface
 {
 };
 
 #endif // QT_NO_COMPONENT
 
 #endif // QCOM_H