- Update smartp to version 1.1: add support for dynamic casting

git-svn-id: svn://svn.gna.org/svn/sgpemv2/trunk@501 3ecf2c5c-341e-0410-92b4-d18e462d057c

src/templates/smartp.hh

@@ -18,15 +18,17 @@
 #define SMARTP_HH 1
 
 #include <new>
+#include <typeinfo>
 
 namespace memory {
   
   /** \brief A simple reference counted smart pointer
    *
    *  \author Matteo Settenvini
-   *  \version 1.0
-   *  \date October 2005  
-   *
+   *  
+   *  \version \c 1.1, March 7th, 2006 - Add support for dynamic casting
+   *  \version \c 1.0, October 10th, 2006 - Initial stable release
+   * 
    *  This template is a smart pointer which uses
    *  a simple mechanism of reference count to
    *  keep track of when and if a stored object
@@ -115,6 +117,35 @@ namespace memory {
      * \return The number of references */
     inline unsigned int alive_refs() const throw();
 
+
+    /** \brief Dynamic cast the stored pointer 
+     * to another type
+     *
+     * This functions tries to cast the stored
+     * object to the given type.
+     *
+     * \param U The type to cast to.
+     * \return A reference of the casted type
+     * \exception bad_alloc Raise this exception if 
+     * the cast isn't successful.
+     */
+    template<typename U>
+    inline U& cast_to() throw(std::bad_cast);
+
+    /** \brief Dynamic cast the stored pointer 
+     * to another type
+     *
+     * This functions tries to cast the stored
+     * object to the given type. 
+     *
+     * \param U The type to cast to.
+     * \return A const reference of the casted type
+     * \exception bad_alloc Raise this exception if 
+     * the cast isn't successful.
+     */
+    template<typename U>
+    inline const U& cast_to() const throw(std::bad_cast);
+    
   private:
     struct contents_type {
       T*            ptr;

src/templates/smartp.tcc

@@ -140,6 +140,30 @@ namespace memory {
     return _contents->ptr != 0 ? _contents->rc : 0;
   }
 
+
+  template<typename T, bool isArray>
+  template<typename U>
+  U& 
+  smart_ptr<T,isArray>::cast_to() throw(std::bad_cast) 
+  {
+    if(_contents->ptr != 0)
+      return dynamic_cast<U&>(*_contents->ptr);
+    else
+      throw std::bad_cast();
+  }
+
+
+  template<typename T, bool isArray>
+  template<typename U>
+  const U&
+  smart_ptr<T, isArray>::cast_to() const throw(std::bad_cast)
+  {
+    if(_contents->ptr != 0)
+      return dynamic_cast<U&>(*_contents->ptr);
+    else
+      throw std::bad_cast();
+  }
+
 } //~ namespace memory
 
 #endif