1 ////////////////////////////////////////////////////////////////////////////// 2 // 3 // (C) Copyright Ion Gaztanaga 2014-2015. Distributed under the Boost 4 // Software License, Version 1.0. (See accompanying file 5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 6 // 7 // See http://www.boost.org/libs/container for documentation. 8 // 9 ////////////////////////////////////////////////////////////////////////////// 10 11 #ifndef BOOST_CONTAINER_NEW_ALLOCATOR_HPP 12 #define BOOST_CONTAINER_NEW_ALLOCATOR_HPP 13 14 #ifndef BOOST_CONFIG_HPP 15 # include <boost/config.hpp> 16 #endif 17 18 #if defined(BOOST_HAS_PRAGMA_ONCE) 19 # pragma once 20 #endif 21 22 #include <boost/container/detail/config_begin.hpp> 23 #include <boost/container/detail/workaround.hpp> 24 #include <boost/container/throw_exception.hpp> 25 #include <cstddef> 26 27 //!\file 28 29 namespace boost { 30 namespace container { 31 32 /// @cond 33 34 template<bool Value> 35 struct new_allocator_bool 36 { static const bool value = Value; }; 37 38 template<class T> 39 class new_allocator; 40 41 /// @endcond 42 43 //! Specialization of new_allocator for void types 44 template<> 45 class new_allocator<void> 46 { 47 public: 48 typedef void value_type; 49 typedef void * pointer; 50 typedef const void* const_pointer; 51 //!A integral constant of type bool with value true 52 typedef BOOST_CONTAINER_IMPDEF(new_allocator_bool<true>) propagate_on_container_move_assignment; 53 //!A integral constant of type bool with value true 54 typedef BOOST_CONTAINER_IMPDEF(new_allocator_bool<true>) is_always_equal; 55 // reference-to-void members are impossible 56 57 //!Obtains an new_allocator that allocates 58 //!objects of type T2 59 template<class T2> 60 struct rebind 61 { 62 typedef new_allocator< T2> other; 63 }; 64 65 //!Default constructor 66 //!Never throws new_allocator()67 new_allocator() BOOST_NOEXCEPT_OR_NOTHROW 68 {} 69 70 //!Constructor from other new_allocator. 71 //!Never throws new_allocator(const new_allocator &)72 new_allocator(const new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 73 {} 74 75 //!Constructor from related new_allocator. 76 //!Never throws 77 template<class T2> new_allocator(const new_allocator<T2> &)78 new_allocator(const new_allocator<T2> &) BOOST_NOEXCEPT_OR_NOTHROW 79 {} 80 81 //!Swaps two allocators, does nothing 82 //!because this new_allocator is stateless swap(new_allocator &,new_allocator &)83 friend void swap(new_allocator &, new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 84 {} 85 86 //!An new_allocator always compares to true, as memory allocated with one 87 //!instance can be deallocated by another instance operator ==(const new_allocator &,const new_allocator &)88 friend bool operator==(const new_allocator &, const new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 89 { return true; } 90 91 //!An new_allocator always compares to false, as memory allocated with one 92 //!instance can be deallocated by another instance operator !=(const new_allocator &,const new_allocator &)93 friend bool operator!=(const new_allocator &, const new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 94 { return false; } 95 }; 96 97 98 //! This class is a reduced STL-compatible allocator that allocates memory using operator new 99 template<class T> 100 class new_allocator 101 { 102 public: 103 typedef T value_type; 104 typedef T * pointer; 105 typedef const T * const_pointer; 106 typedef T & reference; 107 typedef const T & const_reference; 108 typedef std::size_t size_type; 109 typedef std::ptrdiff_t difference_type; 110 //!A integral constant of type bool with value true 111 typedef BOOST_CONTAINER_IMPDEF(new_allocator_bool<true>) propagate_on_container_move_assignment; 112 //!A integral constant of type bool with value true 113 typedef BOOST_CONTAINER_IMPDEF(new_allocator_bool<true>) is_always_equal; 114 115 //!Obtains an new_allocator that allocates 116 //!objects of type T2 117 template<class T2> 118 struct rebind 119 { 120 typedef new_allocator<T2> other; 121 }; 122 123 //!Default constructor 124 //!Never throws new_allocator()125 new_allocator() BOOST_NOEXCEPT_OR_NOTHROW 126 {} 127 128 //!Constructor from other new_allocator. 129 //!Never throws new_allocator(const new_allocator &)130 new_allocator(const new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 131 {} 132 133 //!Constructor from related new_allocator. 134 //!Never throws 135 template<class T2> new_allocator(const new_allocator<T2> &)136 new_allocator(const new_allocator<T2> &) BOOST_NOEXCEPT_OR_NOTHROW 137 {} 138 139 //!Allocates memory for an array of count elements. 140 //!Throws std::bad_alloc if there is no enough memory allocate(size_type count)141 pointer allocate(size_type count) 142 { 143 if(BOOST_UNLIKELY(count > this->max_size())) 144 throw_bad_alloc(); 145 return static_cast<T*>(::operator new(count*sizeof(T))); 146 } 147 148 //!Deallocates previously allocated memory. 149 //!Never throws deallocate(pointer ptr,size_type)150 void deallocate(pointer ptr, size_type) BOOST_NOEXCEPT_OR_NOTHROW 151 { ::operator delete((void*)ptr); } 152 153 //!Returns the maximum number of elements that could be allocated. 154 //!Never throws max_size() const155 size_type max_size() const BOOST_NOEXCEPT_OR_NOTHROW 156 { return size_type(-1)/sizeof(T); } 157 158 //!Swaps two allocators, does nothing 159 //!because this new_allocator is stateless swap(new_allocator &,new_allocator &)160 friend void swap(new_allocator &, new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 161 {} 162 163 //!An new_allocator always compares to true, as memory allocated with one 164 //!instance can be deallocated by another instance operator ==(const new_allocator &,const new_allocator &)165 friend bool operator==(const new_allocator &, const new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 166 { return true; } 167 168 //!An new_allocator always compares to false, as memory allocated with one 169 //!instance can be deallocated by another instance operator !=(const new_allocator &,const new_allocator &)170 friend bool operator!=(const new_allocator &, const new_allocator &) BOOST_NOEXCEPT_OR_NOTHROW 171 { return false; } 172 }; 173 174 } //namespace container { 175 } //namespace boost { 176 177 #include <boost/container/detail/config_end.hpp> 178 179 #endif //BOOST_CONTAINER_NEW_ALLOCATOR_HPP 180