| /////////////////////////////////////////////////////////////////////////////// |
| // |
| // (C) Copyright Ion Gaztanaga 2005-2009. Distributed under the Boost |
| // Software License, Version 1.0. (See accompanying file |
| // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| // |
| // See http://www.boost.org/libs/interprocess for documentation. |
| // |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #ifndef BOOST_INTERPROCESS_EXPAND_BWD_TEST_ALLOCATOR_HPP |
| #define BOOST_INTERPROCESS_EXPAND_BWD_TEST_ALLOCATOR_HPP |
| |
| #if (defined _MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif |
| |
| #include <boost/interprocess/detail/config_begin.hpp> |
| #include <boost/interprocess/detail/workaround.hpp> |
| |
| #include <boost/interprocess/interprocess_fwd.hpp> |
| #include <boost/interprocess/containers/allocation_type.hpp> |
| #include <boost/assert.hpp> |
| #include <boost/interprocess/detail/utilities.hpp> |
| #include <boost/interprocess/containers/version_type.hpp> |
| #include <boost/interprocess/exceptions.hpp> |
| #include <memory> |
| #include <algorithm> |
| #include <cstddef> |
| #include <stdexcept> |
| #include <cassert> |
| |
| //!\file |
| //!Describes an allocator to test expand capabilities |
| |
| namespace boost { |
| namespace interprocess { |
| namespace test { |
| |
| //This allocator just allows two allocations. The first one will return |
| //mp_buffer + m_offset configured in the constructor. The second one |
| //will return mp_buffer. |
| template<class T> |
| class expand_bwd_test_allocator |
| { |
| private: |
| typedef expand_bwd_test_allocator<T> self_t; |
| typedef void * aux_pointer_t; |
| typedef const void * cvoid_ptr; |
| |
| template<class T2> |
| expand_bwd_test_allocator& operator=(const expand_bwd_test_allocator<T2>&); |
| |
| expand_bwd_test_allocator& operator=(const expand_bwd_test_allocator&); |
| |
| public: |
| typedef T value_type; |
| typedef T * pointer; |
| typedef const T * const_pointer; |
| typedef typename detail::add_reference |
| <value_type>::type reference; |
| typedef typename detail::add_reference |
| <const value_type>::type const_reference; |
| typedef std::size_t size_type; |
| typedef std::ptrdiff_t difference_type; |
| |
| typedef boost::interprocess::version_type<expand_bwd_test_allocator, 2> version; |
| |
| template<class T2> |
| struct rebind |
| { typedef expand_bwd_test_allocator<T2> other; }; |
| |
| //!Constructor from the segment manager. Never throws |
| expand_bwd_test_allocator(T *buffer, size_type size, difference_type offset) |
| : mp_buffer(buffer), m_size(size) |
| , m_offset(offset), m_allocations(0){ } |
| |
| //!Constructor from other expand_bwd_test_allocator. Never throws |
| expand_bwd_test_allocator(const expand_bwd_test_allocator &other) |
| : mp_buffer(other.mp_buffer), m_size(other.m_size) |
| , m_offset(other.m_offset), m_allocations(0){ } |
| |
| //!Constructor from related expand_bwd_test_allocator. Never throws |
| template<class T2> |
| expand_bwd_test_allocator(const expand_bwd_test_allocator<T2> &other) |
| : mp_buffer(other.mp_buffer), m_size(other.m_size) |
| , m_offset(other.m_offset), m_allocations(0){ } |
| |
| pointer address(reference value) |
| { return pointer(addressof(value)); } |
| |
| const_pointer address(const_reference value) const |
| { return const_pointer(addressof(value)); } |
| |
| pointer allocate(size_type , cvoid_ptr hint = 0) |
| { (void)hint; return 0; } |
| |
| void deallocate(const pointer &, size_type) |
| {} |
| |
| template<class Convertible> |
| void construct(pointer ptr, const Convertible &value) |
| { new((void*)ptr) value_type(value); } |
| |
| void destroy(pointer ptr) |
| { (*ptr).~value_type(); } |
| |
| size_type max_size() const |
| { return m_size; } |
| |
| friend void swap(self_t &alloc1, self_t &alloc2) |
| { |
| detail::do_swap(alloc1.mp_buffer, alloc2.mp_buffer); |
| detail::do_swap(alloc1.m_size, alloc2.m_size); |
| detail::do_swap(alloc1.m_offset, alloc2.m_offset); |
| } |
| |
| //Experimental version 2 expand_bwd_test_allocator functions |
| |
| std::pair<pointer, bool> |
| allocation_command(boost::interprocess::allocation_type command, |
| size_type limit_size, |
| size_type preferred_size, |
| size_type &received_size, const pointer &reuse = 0) |
| { |
| (void)preferred_size; (void)reuse; (void)command; |
| //This allocator only expands backwards! |
| assert(m_allocations == 0 || (command & boost::interprocess::expand_bwd)); |
| |
| received_size = limit_size; |
| |
| if(m_allocations == 0){ |
| if((m_offset + limit_size) > m_size){ |
| assert(0); |
| } |
| ++m_allocations; |
| return std::pair<pointer, bool>(mp_buffer + m_offset, false); |
| } |
| else if(m_allocations == 1){ |
| if(limit_size > m_size){ |
| assert(0); |
| } |
| ++m_allocations; |
| return std::pair<pointer, bool>(mp_buffer, true); |
| } |
| else{ |
| assert(0); |
| throw std::bad_alloc(); |
| } |
| } |
| |
| //!Returns maximum the number of objects the previously allocated memory |
| //!pointed by p can hold. |
| size_type size(const pointer &p) const |
| { (void)p; return m_size; } |
| |
| //!Allocates just one object. Memory allocated with this function |
| //!must be deallocated only with deallocate_one(). |
| //!Throws boost::interprocess::bad_alloc if there is no enough memory |
| pointer allocate_one() |
| { return this->allocate(1); } |
| |
| //!Deallocates memory previously allocated with allocate_one(). |
| //!You should never use deallocate_one to deallocate memory allocated |
| //!with other functions different from allocate_one(). Never throws |
| void deallocate_one(const pointer &p) |
| { return this->deallocate(p, 1); } |
| |
| pointer mp_buffer; |
| size_type m_size; |
| difference_type m_offset; |
| char m_allocations; |
| }; |
| |
| //!Equality test for same type of expand_bwd_test_allocator |
| template<class T> inline |
| bool operator==(const expand_bwd_test_allocator<T> &alloc1, |
| const expand_bwd_test_allocator<T> &alloc2) |
| { return false; } |
| |
| //!Inequality test for same type of expand_bwd_test_allocator |
| template<class T> inline |
| bool operator!=(const expand_bwd_test_allocator<T> &alloc1, |
| const expand_bwd_test_allocator<T> &alloc2) |
| { return true; } |
| |
| } //namespace test { |
| } //namespace interprocess { |
| } //namespace boost { |
| |
| #include <boost/interprocess/detail/config_end.hpp> |
| |
| #endif //BOOST_INTERPROCESS_EXPAND_BWD_TEST_ALLOCATOR_HPP |
| |