+/** The base class for inspircd classes that support reference counting.
+ * Any objects that do not have a well-defined lifetime should inherit from
+ * this, and should be assigned to a reference<type> object to establish their
+ * lifetime.
+ *
+ * Reference objects should not hold circular references back to themselves,
+ * even indirectly; this will cause a memory leak because the count will never
+ * drop to zero.
+ *
+ * Using a normal pointer for the object is recommended if you can assure that
+ * at least one reference<> will remain as long as that pointer is used; this
+ * will avoid the slight overhead of changing the reference count.
+ */
+class CoreExport refcountbase
+{
+ mutable unsigned int refcount;
+ public:
+ refcountbase();
+ virtual ~refcountbase();
+ inline unsigned int GetReferenceCount() const { return refcount; }
+ static inline void* operator new(size_t, void* m) { return m; }
+ static void* operator new(size_t);
+ static void operator delete(void*);
+ inline void refcount_inc() const { refcount++; }
+ inline bool refcount_dec() const { refcount--; return !refcount; }
+ private:
+ // uncopyable
+ refcountbase(const refcountbase&);
+ void operator=(const refcountbase&);
+};
+
+/** Base class for use count tracking. Uses reference<>, but does not
+ * cause object deletion when the last user is removed.
+ *
+ * Safe for use as a second parent class; will not add a second vtable.
+ */
+class CoreExport usecountbase
+{
+ mutable unsigned int usecount;
+ public:
+ usecountbase() : usecount(0) { }
+ ~usecountbase();
+ inline unsigned int GetUseCount() const { return usecount; }
+ inline void refcount_inc() const { usecount++; }
+ inline bool refcount_dec() const { usecount--; return false; }
+ private:
+ // uncopyable
+ usecountbase(const usecountbase&);
+ void operator=(const usecountbase&);
+};
+
+template <typename T>
+class reference
+{
+ T* value;
+ public:
+ reference() : value(0) { }
+ reference(T* v) : value(v) { if (value) value->refcount_inc(); }
+ reference(const reference<T>& v) : value(v.value) { if (value) value->refcount_inc(); }
+ reference<T>& operator=(const reference<T>& other)
+ {
+ if (other.value)
+ other.value->refcount_inc();
+ this->reference::~reference();
+ value = other.value;
+ return *this;
+ }
+
+ ~reference()
+ {
+ if (value && value->refcount_dec())
+ delete value;
+ }
+
+ inline reference<T>& operator=(T* other)
+ {
+ if (value != other)
+ {
+ if (value && value->refcount_dec())
+ delete value;
+ value = other;
+ if (value)
+ value->refcount_inc();
+ }
+
+ return *this;
+ }
+
+ inline operator bool() const { return (value != NULL); }
+ inline operator T*() const { return value; }
+ inline T* operator->() const { return value; }
+ inline T& operator*() const { return *value; }
+ inline bool operator<(const reference<T>& other) const { return value < other.value; }
+ inline bool operator>(const reference<T>& other) const { return value > other.value; }
+ static inline void* operator new(size_t, void* m) { return m; }
+ private:
+#ifndef _WIN32
+ static void* operator new(size_t);
+ static void operator delete(void*);