1#ifndef BOOST_ARCHIVE_DETAIL_HELPER_COLLECTION_HPP
2#define BOOST_ARCHIVE_DETAIL_HELPER_COLLECTION_HPP
3
4// MS compatible compilers support #pragma once
5#if defined(_MSC_VER) && (_MSC_VER >= 1020)
6# pragma once
7#endif
8
9/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
10// helper_collection.hpp: archive support for run-time helpers
11
12// (C) Copyright 2002-2008 Robert Ramey and Joaquin M Lopez Munoz
13// Use, modification and distribution is subject to the Boost Software
14// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
15// http://www.boost.org/LICENSE_1_0.txt)
16
17// See http://www.boost.org for updates, documentation, and revision history.
18
19#include <cstddef> // NULL
20#include <vector>
21#include <utility>
22#include <memory>
23#include <algorithm>
24
25#include <boost/config.hpp>
26
27#include <boost/smart_ptr/shared_ptr.hpp>
28#include <boost/smart_ptr/make_shared.hpp>
29
30namespace boost {
31
32namespace archive {
33namespace detail {
34
35class helper_collection
36{
37 helper_collection(const helper_collection&); // non-copyable
38 helper_collection& operator = (const helper_collection&); // non-copyable
39
40 // note: we dont' actually "share" the function object pointer
41 // we only use shared_ptr to make sure that it get's deleted
42
43 typedef std::pair<
44 const void *,
45 boost::shared_ptr<void>
46 > helper_value_type;
47 template<class T>
48 boost::shared_ptr<void> make_helper_ptr(){
49 // use boost::shared_ptr rather than std::shared_ptr to maintain
50 // c++03 compatibility
51 return boost::make_shared<T>();
52 }
53
54 typedef std::vector<helper_value_type> collection;
55 collection m_collection;
56
57 struct predicate {
58 BOOST_DEFAULTED_FUNCTION(predicate(const predicate& rhs), : m_ti(rhs.m_ti) {})
59 BOOST_DELETED_FUNCTION(predicate & operator=(const predicate & rhs))
60 public:
61 const void * const m_ti;
62 bool operator()(helper_value_type const &rhs){
63 return m_ti == rhs.first;
64 }
65 predicate(const void * ti) :
66 m_ti(ti)
67 {}
68 };
69protected:
70 helper_collection(){}
71 ~helper_collection(){}
72public:
73 template<typename Helper>
74 Helper& find_helper(void * const id = 0) {
75 collection::const_iterator it =
76 std::find_if(
77 first: m_collection.begin(),
78 last: m_collection.end(),
79 pred: predicate(id)
80 );
81
82 void * rval = 0;
83 if(it == m_collection.end()){
84 m_collection.push_back(
85 std::make_pair(id, make_helper_ptr<Helper>())
86 );
87 rval = m_collection.back().second.get();
88 }
89 else{
90 rval = it->second.get();
91 }
92 return *static_cast<Helper *>(rval);
93 }
94};
95
96} // namespace detail
97} // namespace serialization
98} // namespace boost
99
100#endif // BOOST_ARCHIVE_DETAIL_HELPER_COLLECTION_HPP
101

source code of boost/libs/serialization/include/boost/archive/detail/helper_collection.hpp