1 // (C) Copyright Jonathan Turkanis 2004-2005.

     2 // Distributed under the Boost Software License, Version 1.0. (See accompanying

     3 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)

     4 

     5 // Contains the definition of move_ptrs::default_deleter, the default

     6 // Deleter template argument to move_ptr. Uses a technique of Daniel

     7 // Wallin to capture the type of a pointer at the time the deleter 

     8 // is constructed, so that move_ptrs can delete objects of incomplete 

     9 // type by default.

    10 

    11 #ifndef BOOST_MOVE_PTR_DEFAULT_DELETER_HPP_INCLUDED

    12 #define BOOST_MOVE_PTR_DEFAULT_DELETER_HPP_INCLUDED 

    13 

    14 #include <boost/checked_delete.hpp>

    15 #include <boost/mpl/if.hpp>

    16 #include <boost/type_traits/is_array.hpp>

    17 #include <boost/type_traits/remove_bounds.hpp>

    18 

    19 namespace boost { namespace ptr_container_detail { namespace move_ptrs {

    20 

    21 namespace ptr_container_detail {

    22 

    23 template<typename T>

    24 struct deleter_base {

    25     typedef void (*deleter)(T*);

    26     deleter_base(deleter d) { delete_ = d; }

    27     void operator() (T* t) const { delete_(t); }

    28     static deleter delete_;

    29 };

    30 

    31 template<class T>

    32 typename deleter_base<T>::deleter 

    33 deleter_base<T>::delete_;

    34 

    35 template<typename T>

    36 struct scalar_deleter : deleter_base<T> {

    37     typedef deleter_base<T> base;

    38     scalar_deleter() : base(do_delete) { }

    39     static void do_delete(T* t) { checked_delete(t); }

    40 };

    41 

    42 template<typename T>

    43 struct array_deleter 

    44     : deleter_base<typename remove_bounds<T>::type>

    45 {

    46     typedef typename remove_bounds<T>::type element_type;

    47     typedef deleter_base<element_type> base;

    48     array_deleter() : base(do_delete) { }

    49     static void do_delete(element_type* t) { checked_array_delete(t); }

    50 };

    51 

    52 } // End namespace ptr_container_detail.

    53 

    54 template<typename T>

    55 struct default_deleter

    56     : mpl::if_<

    57           is_array<T>,

    58           ptr_container_detail::array_deleter<T>,

    59           ptr_container_detail::scalar_deleter<T>

    60       >::type

    61 { 

    62     default_deleter() { }

    63     template<typename TT>

    64     default_deleter(default_deleter<TT> tt) { }

    65 };

    66 

    67 } } } // End namespaces ptr_container_detail, move_ptrs, boost.

    68 

    69 #endif // #ifndef BOOST_MOVE_PTR_DEFAULT_DELETER_HPP_INCLUDED