| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // (C) Copyright Ion Gaztanaga 2005-2012. 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_MEM_ALGO_RBTREE_BEST_FIT_HPP |
| #define BOOST_INTERPROCESS_MEM_ALGO_RBTREE_BEST_FIT_HPP |
| |
| #ifndef BOOST_CONFIG_HPP |
| # include <boost/config.hpp> |
| #endif |
| # |
| #if defined(BOOST_HAS_PRAGMA_ONCE) |
| # pragma once |
| #endif |
| |
| #include <boost/interprocess/detail/config_begin.hpp> |
| #include <boost/interprocess/detail/workaround.hpp> |
| |
| // interprocess |
| #include <boost/interprocess/containers/allocation_type.hpp> |
| #include <boost/interprocess/exceptions.hpp> |
| #include <boost/interprocess/interprocess_fwd.hpp> |
| #include <boost/interprocess/mem_algo/detail/mem_algo_common.hpp> |
| #include <boost/interprocess/offset_ptr.hpp> |
| #include <boost/interprocess/sync/scoped_lock.hpp> |
| // interprocess/detail |
| #include <boost/interprocess/detail/min_max.hpp> |
| #include <boost/interprocess/detail/math_functions.hpp> |
| #include <boost/interprocess/detail/type_traits.hpp> |
| #include <boost/interprocess/detail/utilities.hpp> |
| // container |
| #include <boost/container/detail/multiallocation_chain.hpp> |
| // container/detail |
| #include <boost/container/detail/placement_new.hpp> |
| // move/detail |
| #include <boost/move/detail/type_traits.hpp> //make_unsigned, alignment_of |
| // intrusive |
| #include <boost/intrusive/pointer_traits.hpp> |
| #include <boost/intrusive/set.hpp> |
| // other boost |
| #include <boost/assert.hpp> |
| #include <boost/static_assert.hpp> |
| // std |
| #include <climits> |
| #include <cstring> |
| |
| //#define BOOST_INTERPROCESS_RBTREE_BEST_FIT_ABI_V1_HPP |
| //to maintain ABI compatible with the original version |
| //ABI had to be updated to fix compatibility issues when |
| //sharing shared memory between 32 adn 64 bit processes. |
| |
| //!\file |
| //!Describes a best-fit algorithm based in an intrusive red-black tree used to allocate |
| //!objects in shared memory. This class is intended as a base class for single segment |
| //!and multi-segment implementations. |
| |
| namespace boost { |
| namespace interprocess { |
| |
| //!This class implements an algorithm that stores the free nodes in a red-black tree |
| //!to have logarithmic search/insert times. |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| class rbtree_best_fit |
| { |
| #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) |
| //Non-copyable |
| rbtree_best_fit(); |
| rbtree_best_fit(const rbtree_best_fit &); |
| rbtree_best_fit &operator=(const rbtree_best_fit &); |
| |
| private: |
| struct block_ctrl; |
| typedef typename boost::intrusive:: |
| pointer_traits<VoidPointer>::template |
| rebind_pointer<block_ctrl>::type block_ctrl_ptr; |
| |
| typedef typename boost::intrusive:: |
| pointer_traits<VoidPointer>::template |
| rebind_pointer<char>::type char_ptr; |
| |
| #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED |
| |
| public: |
| //!Shared mutex family used for the rest of the Interprocess framework |
| typedef MutexFamily mutex_family; |
| //!Pointer type to be used with the rest of the Interprocess framework |
| typedef VoidPointer void_pointer; |
| typedef ipcdetail::basic_multiallocation_chain<VoidPointer> multiallocation_chain; |
| |
| typedef typename boost::intrusive::pointer_traits<char_ptr>::difference_type difference_type; |
| typedef typename boost::container::container_detail::make_unsigned<difference_type>::type size_type; |
| |
| #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) |
| |
| private: |
| |
| typedef typename bi::make_set_base_hook |
| < bi::void_pointer<VoidPointer> |
| , bi::optimize_size<true> |
| , bi::link_mode<bi::normal_link> >::type TreeHook; |
| |
| struct SizeHolder |
| { |
| //!This block's memory size (including block_ctrl |
| //!header) in Alignment units |
| size_type m_prev_size : sizeof(size_type)*CHAR_BIT; |
| size_type m_size : sizeof(size_type)*CHAR_BIT - 2; |
| size_type m_prev_allocated : 1; |
| size_type m_allocated : 1; |
| }; |
| |
| //!Block control structure |
| struct block_ctrl |
| : public SizeHolder, public TreeHook |
| { |
| block_ctrl() |
| { this->m_size = 0; this->m_allocated = 0, this->m_prev_allocated = 0; } |
| |
| friend bool operator<(const block_ctrl &a, const block_ctrl &b) |
| { return a.m_size < b.m_size; } |
| friend bool operator==(const block_ctrl &a, const block_ctrl &b) |
| { return a.m_size == b.m_size; } |
| }; |
| |
| struct size_block_ctrl_compare |
| { |
| bool operator()(size_type size, const block_ctrl &block) const |
| { return size < block.m_size; } |
| |
| bool operator()(const block_ctrl &block, size_type size) const |
| { return block.m_size < size; } |
| }; |
| |
| //!Shared mutex to protect memory allocate/deallocate |
| typedef typename MutexFamily::mutex_type mutex_type; |
| typedef typename bi::make_multiset |
| <block_ctrl, bi::base_hook<TreeHook> >::type Imultiset; |
| |
| typedef typename Imultiset::iterator imultiset_iterator; |
| typedef typename Imultiset::const_iterator imultiset_const_iterator; |
| |
| //!This struct includes needed data and derives from |
| //!mutex_type to allow EBO when using null mutex_type |
| struct header_t : public mutex_type |
| { |
| Imultiset m_imultiset; |
| |
| //!The extra size required by the segment |
| size_type m_extra_hdr_bytes; |
| //!Allocated bytes for internal checking |
| size_type m_allocated; |
| //!The size of the memory segment |
| size_type m_size; |
| } m_header; |
| |
| friend class ipcdetail::memory_algorithm_common<rbtree_best_fit>; |
| |
| typedef ipcdetail::memory_algorithm_common<rbtree_best_fit> algo_impl_t; |
| |
| public: |
| #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED |
| |
| //!Constructor. "size" is the total size of the managed memory segment, |
| //!"extra_hdr_bytes" indicates the extra bytes beginning in the sizeof(rbtree_best_fit) |
| //!offset that the allocator should not use at all. |
| rbtree_best_fit (size_type size, size_type extra_hdr_bytes); |
| |
| //!Destructor. |
| ~rbtree_best_fit(); |
| |
| //!Obtains the minimum size needed by the algorithm |
| static size_type get_min_size (size_type extra_hdr_bytes); |
| |
| //Functions for single segment management |
| |
| //!Allocates bytes, returns 0 if there is not more memory |
| void* allocate (size_type nbytes); |
| |
| #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) |
| |
| //Experimental. Dont' use |
| |
| //!Multiple element allocation, same size |
| void allocate_many(size_type elem_bytes, size_type num_elements, multiallocation_chain &chain) |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| algo_impl_t::allocate_many(this, elem_bytes, num_elements, chain); |
| } |
| |
| //!Multiple element allocation, different size |
| void allocate_many(const size_type *elem_sizes, size_type n_elements, size_type sizeof_element, multiallocation_chain &chain) |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| algo_impl_t::allocate_many(this, elem_sizes, n_elements, sizeof_element, chain); |
| } |
| |
| //!Multiple element allocation, different size |
| void deallocate_many(multiallocation_chain &chain); |
| |
| #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED |
| |
| //!Deallocates previously allocated bytes |
| void deallocate (void *addr); |
| |
| //!Returns the size of the memory segment |
| size_type get_size() const; |
| |
| //!Returns the number of free bytes of the segment |
| size_type get_free_memory() const; |
| |
| //!Initializes to zero all the memory that's not in use. |
| //!This function is normally used for security reasons. |
| void zero_free_memory(); |
| |
| //!Increases managed memory in |
| //!extra_size bytes more |
| void grow(size_type extra_size); |
| |
| //!Decreases managed memory as much as possible |
| void shrink_to_fit(); |
| |
| //!Returns true if all allocated memory has been deallocated |
| bool all_memory_deallocated(); |
| |
| //!Makes an internal sanity check |
| //!and returns true if success |
| bool check_sanity(); |
| |
| template<class T> |
| T * allocation_command (boost::interprocess::allocation_type command, size_type limit_size, |
| size_type &prefer_in_recvd_out_size, T *&reuse); |
| |
| void * raw_allocation_command (boost::interprocess::allocation_type command, size_type limit_object, |
| size_type &prefer_in_recvd_out_size, |
| void *&reuse_ptr, size_type sizeof_object = 1); |
| |
| //!Returns the size of the buffer previously allocated pointed by ptr |
| size_type size(const void *ptr) const; |
| |
| //!Allocates aligned bytes, returns 0 if there is not more memory. |
| //!Alignment must be power of 2 |
| void* allocate_aligned (size_type nbytes, size_type alignment); |
| |
| #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) |
| private: |
| static size_type priv_first_block_offset_from_this(const void *this_ptr, size_type extra_hdr_bytes); |
| |
| block_ctrl *priv_first_block(); |
| |
| block_ctrl *priv_end_block(); |
| |
| void* priv_allocation_command(boost::interprocess::allocation_type command, size_type limit_size, |
| size_type &prefer_in_recvd_out_size, void *&reuse_ptr, size_type sizeof_object); |
| |
| |
| //!Real allocation algorithm with min allocation option |
| void * priv_allocate( boost::interprocess::allocation_type command |
| , size_type limit_size, size_type &prefer_in_recvd_out_size |
| , void *&reuse_ptr, size_type backwards_multiple = 1); |
| |
| //!Obtains the block control structure of the user buffer |
| static block_ctrl *priv_get_block(const void *ptr); |
| |
| //!Obtains the pointer returned to the user from the block control |
| static void *priv_get_user_buffer(const block_ctrl *block); |
| |
| //!Returns the number of total units that a user buffer |
| //!of "userbytes" bytes really occupies (including header) |
| static size_type priv_get_total_units(size_type userbytes); |
| |
| //!Real expand function implementation |
| bool priv_expand(void *ptr, const size_type min_size, size_type &prefer_in_recvd_out_size); |
| |
| //!Real expand to both sides implementation |
| void* priv_expand_both_sides(boost::interprocess::allocation_type command |
| ,size_type min_size |
| ,size_type &prefer_in_recvd_out_size |
| ,void *reuse_ptr |
| ,bool only_preferred_backwards |
| ,size_type backwards_multiple); |
| |
| //!Returns true if the previous block is allocated |
| bool priv_is_prev_allocated(block_ctrl *ptr); |
| |
| //!Get a pointer of the "end" block from the first block of the segment |
| static block_ctrl * priv_end_block(block_ctrl *first_segment_block); |
| |
| //!Get a pointer of the "first" block from the end block of the segment |
| static block_ctrl * priv_first_block(block_ctrl *end_segment_block); |
| |
| //!Get poitner of the previous block (previous block must be free) |
| static block_ctrl * priv_prev_block(block_ctrl *ptr); |
| |
| //!Get the size in the tail of the previous block |
| static block_ctrl * priv_next_block(block_ctrl *ptr); |
| |
| //!Check if this block is free (not allocated) |
| bool priv_is_allocated_block(block_ctrl *ptr); |
| |
| //!Marks the block as allocated |
| void priv_mark_as_allocated_block(block_ctrl *ptr); |
| |
| //!Marks the block as allocated |
| void priv_mark_new_allocated_block(block_ctrl *ptr) |
| { return priv_mark_as_allocated_block(ptr); } |
| |
| //!Marks the block as allocated |
| void priv_mark_as_free_block(block_ctrl *ptr); |
| |
| //!Checks if block has enough memory and splits/unlinks the block |
| //!returning the address to the users |
| void* priv_check_and_allocate(size_type units |
| ,block_ctrl* block |
| ,size_type &received_size); |
| //!Real deallocation algorithm |
| void priv_deallocate(void *addr); |
| |
| //!Makes a new memory portion available for allocation |
| void priv_add_segment(void *addr, size_type size); |
| |
| public: |
| |
| static const size_type Alignment = !MemAlignment |
| ? size_type(::boost::container::container_detail::alignment_of |
| < ::boost::container::container_detail::max_align_t>::value) |
| : size_type(MemAlignment) |
| ; |
| |
| private: |
| //Due to embedded bits in size, Alignment must be at least 4 |
| BOOST_STATIC_ASSERT((Alignment >= 4)); |
| //Due to rbtree size optimizations, Alignment must have at least pointer alignment |
| BOOST_STATIC_ASSERT((Alignment >= ::boost::container::container_detail::alignment_of<void_pointer>::value)); |
| static const size_type AlignmentMask = (Alignment - 1); |
| static const size_type BlockCtrlBytes = ipcdetail::ct_rounded_size<sizeof(block_ctrl), Alignment>::value; |
| static const size_type BlockCtrlUnits = BlockCtrlBytes/Alignment; |
| static const size_type AllocatedCtrlBytes = ipcdetail::ct_rounded_size<sizeof(SizeHolder), Alignment>::value; |
| static const size_type AllocatedCtrlUnits = AllocatedCtrlBytes/Alignment; |
| static const size_type EndCtrlBlockBytes = ipcdetail::ct_rounded_size<sizeof(SizeHolder), Alignment>::value; |
| static const size_type EndCtrlBlockUnits = EndCtrlBlockBytes/Alignment; |
| static const size_type MinBlockUnits = BlockCtrlUnits; |
| static const size_type UsableByPreviousChunk = sizeof(size_type); |
| |
| //Make sure the maximum alignment is power of two |
| BOOST_STATIC_ASSERT((0 == (Alignment & (Alignment - size_type(1u))))); |
| #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED |
| public: |
| static const size_type PayloadPerAllocation = AllocatedCtrlBytes - UsableByPreviousChunk; |
| }; |
| |
| #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::size_type |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment> |
| ::priv_first_block_offset_from_this(const void *this_ptr, size_type extra_hdr_bytes) |
| { |
| size_type uint_this = (std::size_t)this_ptr; |
| size_type main_hdr_end = uint_this + sizeof(rbtree_best_fit) + extra_hdr_bytes; |
| size_type aligned_main_hdr_end = ipcdetail::get_rounded_size(main_hdr_end, Alignment); |
| size_type block1_off = aligned_main_hdr_end - uint_this; |
| algo_impl_t::assert_alignment(aligned_main_hdr_end); |
| algo_impl_t::assert_alignment(uint_this + block1_off); |
| return block1_off; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_add_segment(void *addr, size_type segment_size) |
| { |
| //Check alignment |
| algo_impl_t::check_alignment(addr); |
| //Check size |
| BOOST_ASSERT(segment_size >= (BlockCtrlBytes + EndCtrlBlockBytes)); |
| |
| //Initialize the first big block and the "end" node |
| block_ctrl *first_big_block = ::new(addr, boost_container_new_t())block_ctrl; |
| first_big_block->m_size = segment_size/Alignment - EndCtrlBlockUnits; |
| BOOST_ASSERT(first_big_block->m_size >= BlockCtrlUnits); |
| |
| //The "end" node is just a node of size 0 with the "end" bit set |
| block_ctrl *end_block = static_cast<block_ctrl*> |
| (new (reinterpret_cast<char*>(addr) + first_big_block->m_size*Alignment)SizeHolder); |
| |
| //This will overwrite the prev part of the "end" node |
| priv_mark_as_free_block (first_big_block); |
| #ifdef BOOST_INTERPROCESS_RBTREE_BEST_FIT_ABI_V1_HPP |
| first_big_block->m_prev_size = end_block->m_size = |
| (reinterpret_cast<char*>(first_big_block) - reinterpret_cast<char*>(end_block))/Alignment; |
| #else |
| first_big_block->m_prev_size = end_block->m_size = |
| (reinterpret_cast<char*>(end_block) - reinterpret_cast<char*>(first_big_block))/Alignment; |
| #endif |
| end_block->m_allocated = 1; |
| first_big_block->m_prev_allocated = 1; |
| |
| BOOST_ASSERT(priv_next_block(first_big_block) == end_block); |
| BOOST_ASSERT(priv_prev_block(end_block) == first_big_block); |
| BOOST_ASSERT(priv_first_block() == first_big_block); |
| BOOST_ASSERT(priv_end_block() == end_block); |
| |
| //Some check to validate the algorithm, since it makes some assumptions |
| //to optimize the space wasted in bookkeeping: |
| |
| //Check that the sizes of the header are placed before the rbtree |
| BOOST_ASSERT(static_cast<void*>(static_cast<SizeHolder*>(first_big_block)) |
| < static_cast<void*>(static_cast<TreeHook*>(first_big_block))); |
| //Insert it in the intrusive containers |
| m_header.m_imultiset.insert(*first_big_block); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment> |
| ::priv_first_block() |
| { |
| size_type block1_off = priv_first_block_offset_from_this(this, m_header.m_extra_hdr_bytes); |
| return reinterpret_cast<block_ctrl *>(reinterpret_cast<char*>(this) + block1_off); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment> |
| ::priv_end_block() |
| { |
| size_type block1_off = priv_first_block_offset_from_this(this, m_header.m_extra_hdr_bytes); |
| const size_type original_first_block_size = m_header.m_size/Alignment*Alignment - block1_off/Alignment*Alignment - EndCtrlBlockBytes; |
| block_ctrl *end_block = reinterpret_cast<block_ctrl*> |
| (reinterpret_cast<char*>(this) + block1_off + original_first_block_size); |
| return end_block; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| rbtree_best_fit(size_type segment_size, size_type extra_hdr_bytes) |
| { |
| //Initialize the header |
| m_header.m_allocated = 0; |
| m_header.m_size = segment_size; |
| m_header.m_extra_hdr_bytes = extra_hdr_bytes; |
| |
| //Now write calculate the offset of the first big block that will |
| //cover the whole segment |
| BOOST_ASSERT(get_min_size(extra_hdr_bytes) <= segment_size); |
| size_type block1_off = priv_first_block_offset_from_this(this, extra_hdr_bytes); |
| priv_add_segment(reinterpret_cast<char*>(this) + block1_off, segment_size - block1_off); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::~rbtree_best_fit() |
| { |
| //There is a memory leak! |
| // BOOST_ASSERT(m_header.m_allocated == 0); |
| // BOOST_ASSERT(m_header.m_root.m_next->m_next == block_ctrl_ptr(&m_header.m_root)); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::grow(size_type extra_size) |
| { |
| //Get the address of the first block |
| block_ctrl *first_block = priv_first_block(); |
| block_ctrl *old_end_block = priv_end_block(); |
| size_type old_border_offset = (size_type)(reinterpret_cast<char*>(old_end_block) - |
| reinterpret_cast<char*>(this)) + EndCtrlBlockBytes; |
| |
| //Update managed buffer's size |
| m_header.m_size += extra_size; |
| |
| //We need at least MinBlockUnits blocks to create a new block |
| if((m_header.m_size - old_border_offset) < MinBlockUnits){ |
| return; |
| } |
| |
| //Now create a new block between the old end and the new end |
| size_type align_offset = (m_header.m_size - old_border_offset)/Alignment; |
| block_ctrl *new_end_block = reinterpret_cast<block_ctrl*> |
| (reinterpret_cast<char*>(old_end_block) + align_offset*Alignment); |
| |
| //the last and first block are special: |
| //new_end_block->m_size & first_block->m_prev_size store the absolute value |
| //between them |
| new_end_block->m_allocated = 1; |
| #ifdef BOOST_INTERPROCESS_RBTREE_BEST_FIT_ABI_V1_HPP |
| new_end_block->m_size = (reinterpret_cast<char*>(first_block) - |
| reinterpret_cast<char*>(new_end_block))/Alignment; |
| #else |
| new_end_block->m_size = (reinterpret_cast<char*>(new_end_block) - |
| reinterpret_cast<char*>(first_block))/Alignment; |
| #endif |
| first_block->m_prev_size = new_end_block->m_size; |
| first_block->m_prev_allocated = 1; |
| BOOST_ASSERT(new_end_block == priv_end_block()); |
| |
| //The old end block is the new block |
| block_ctrl *new_block = old_end_block; |
| new_block->m_size = (reinterpret_cast<char*>(new_end_block) - |
| reinterpret_cast<char*>(new_block))/Alignment; |
| BOOST_ASSERT(new_block->m_size >= BlockCtrlUnits); |
| priv_mark_as_allocated_block(new_block); |
| BOOST_ASSERT(priv_next_block(new_block) == new_end_block); |
| |
| m_header.m_allocated += (size_type)new_block->m_size*Alignment; |
| |
| //Now deallocate the newly created block |
| this->priv_deallocate(priv_get_user_buffer(new_block)); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::shrink_to_fit() |
| { |
| //Get the address of the first block |
| block_ctrl *first_block = priv_first_block(); |
| algo_impl_t::assert_alignment(first_block); |
| |
| //block_ctrl *old_end_block = priv_end_block(first_block); |
| block_ctrl *old_end_block = priv_end_block(); |
| algo_impl_t::assert_alignment(old_end_block); |
| size_type old_end_block_size = old_end_block->m_size; |
| |
| void *unique_buffer = 0; |
| block_ctrl *last_block; |
| //Check if no memory is allocated between the first and last block |
| if(priv_next_block(first_block) == old_end_block){ |
| //If so check if we can allocate memory |
| size_type ignore_recvd = 0; |
| void *ignore_reuse = 0; |
| unique_buffer = priv_allocate(boost::interprocess::allocate_new, 0, ignore_recvd, ignore_reuse); |
| //If not, return, we can't shrink |
| if(!unique_buffer) |
| return; |
| //If we can, mark the position just after the new allocation as the new end |
| algo_impl_t::assert_alignment(unique_buffer); |
| block_ctrl *unique_block = priv_get_block(unique_buffer); |
| BOOST_ASSERT(priv_is_allocated_block(unique_block)); |
| algo_impl_t::assert_alignment(unique_block); |
| last_block = priv_next_block(unique_block); |
| BOOST_ASSERT(!priv_is_allocated_block(last_block)); |
| algo_impl_t::assert_alignment(last_block); |
| } |
| else{ |
| //If memory is allocated, check if the last block is allocated |
| if(priv_is_prev_allocated(old_end_block)) |
| return; |
| //If not, mark last block after the free block |
| last_block = priv_prev_block(old_end_block); |
| } |
| |
| size_type last_block_size = last_block->m_size; |
| |
| //Erase block from the free tree, since we will erase it |
| m_header.m_imultiset.erase(Imultiset::s_iterator_to(*last_block)); |
| |
| size_type shrunk_border_offset = (size_type)(reinterpret_cast<char*>(last_block) - |
| reinterpret_cast<char*>(this)) + EndCtrlBlockBytes; |
| |
| block_ctrl *new_end_block = last_block; |
| algo_impl_t::assert_alignment(new_end_block); |
| |
| //Write new end block attributes |
| #ifdef BOOST_INTERPROCESS_RBTREE_BEST_FIT_ABI_V1_HPP |
| new_end_block->m_size = first_block->m_prev_size = |
| (reinterpret_cast<char*>(first_block) - reinterpret_cast<char*>(new_end_block))/Alignment; |
| #else |
| new_end_block->m_size = first_block->m_prev_size = |
| (reinterpret_cast<char*>(new_end_block) - reinterpret_cast<char*>(first_block))/Alignment; |
| #endif |
| |
| new_end_block->m_allocated = 1; |
| (void)last_block_size; |
| (void)old_end_block_size; |
| BOOST_ASSERT(new_end_block->m_size == (old_end_block_size - last_block_size)); |
| |
| //Update managed buffer's size |
| m_header.m_size = shrunk_border_offset; |
| BOOST_ASSERT(priv_end_block() == new_end_block); |
| if(unique_buffer) |
| priv_deallocate(unique_buffer); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::size_type |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::get_size() const |
| { return m_header.m_size; } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::size_type |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::get_free_memory() const |
| { |
| return m_header.m_size - m_header.m_allocated - |
| priv_first_block_offset_from_this(this, m_header.m_extra_hdr_bytes); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::size_type |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| get_min_size (size_type extra_hdr_bytes) |
| { |
| return (algo_impl_t::ceil_units(sizeof(rbtree_best_fit)) + |
| algo_impl_t::ceil_units(extra_hdr_bytes) + |
| MinBlockUnits + EndCtrlBlockUnits)*Alignment; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline bool rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| all_memory_deallocated() |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| size_type block1_off = |
| priv_first_block_offset_from_this(this, m_header.m_extra_hdr_bytes); |
| |
| return m_header.m_allocated == 0 && |
| m_header.m_imultiset.begin() != m_header.m_imultiset.end() && |
| (++m_header.m_imultiset.begin()) == m_header.m_imultiset.end() |
| && m_header.m_imultiset.begin()->m_size == |
| (m_header.m_size - block1_off - EndCtrlBlockBytes)/Alignment; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| bool rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| check_sanity() |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| imultiset_iterator ib(m_header.m_imultiset.begin()), ie(m_header.m_imultiset.end()); |
| |
| size_type free_memory = 0; |
| |
| //Iterate through all blocks obtaining their size |
| for(; ib != ie; ++ib){ |
| free_memory += (size_type)ib->m_size*Alignment; |
| algo_impl_t::assert_alignment(&*ib); |
| if(!algo_impl_t::check_alignment(&*ib)) |
| return false; |
| } |
| |
| //Check allocated bytes are less than size |
| if(m_header.m_allocated > m_header.m_size){ |
| return false; |
| } |
| |
| size_type block1_off = |
| priv_first_block_offset_from_this(this, m_header.m_extra_hdr_bytes); |
| |
| //Check free bytes are less than size |
| if(free_memory > (m_header.m_size - block1_off)){ |
| return false; |
| } |
| return true; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline void* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| allocate(size_type nbytes) |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| size_type ignore_recvd = nbytes; |
| void *ignore_reuse = 0; |
| return priv_allocate(boost::interprocess::allocate_new, nbytes, ignore_recvd, ignore_reuse); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline void* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| allocate_aligned(size_type nbytes, size_type alignment) |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| return algo_impl_t::allocate_aligned(this, nbytes, alignment); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| template<class T> |
| inline T* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| allocation_command (boost::interprocess::allocation_type command, size_type limit_size, |
| size_type &prefer_in_recvd_out_size, T *&reuse) |
| { |
| void* raw_reuse = reuse; |
| void* const ret = priv_allocation_command(command, limit_size, prefer_in_recvd_out_size, raw_reuse, sizeof(T)); |
| reuse = static_cast<T*>(raw_reuse); |
| BOOST_ASSERT(0 == ((std::size_t)ret % ::boost::container::container_detail::alignment_of<T>::value)); |
| return static_cast<T*>(ret); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline void* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| raw_allocation_command (boost::interprocess::allocation_type command, size_type limit_objects, |
| size_type &prefer_in_recvd_out_objects, void *&reuse_ptr, size_type sizeof_object) |
| { |
| size_type const preferred_objects = prefer_in_recvd_out_objects; |
| if(!sizeof_object) |
| return reuse_ptr = 0, static_cast<void*>(0); |
| if(command & boost::interprocess::try_shrink_in_place){ |
| if(!reuse_ptr) return static_cast<void*>(0); |
| const bool success = algo_impl_t::try_shrink |
| ( this, reuse_ptr, limit_objects*sizeof_object |
| , prefer_in_recvd_out_objects = preferred_objects*sizeof_object); |
| prefer_in_recvd_out_objects /= sizeof_object; |
| return success ? reuse_ptr : 0; |
| } |
| else{ |
| return priv_allocation_command |
| (command, limit_objects, prefer_in_recvd_out_objects, reuse_ptr, sizeof_object); |
| } |
| } |
| |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline void* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_allocation_command (boost::interprocess::allocation_type command, size_type limit_size, |
| size_type &prefer_in_recvd_out_size, |
| void *&reuse_ptr, size_type sizeof_object) |
| { |
| void* ret; |
| size_type const preferred_size = prefer_in_recvd_out_size; |
| size_type const max_count = m_header.m_size/sizeof_object; |
| if(limit_size > max_count || preferred_size > max_count){ |
| return reuse_ptr = 0, static_cast<void*>(0); |
| } |
| size_type l_size = limit_size*sizeof_object; |
| size_type p_size = preferred_size*sizeof_object; |
| size_type r_size; |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| ret = priv_allocate(command, l_size, r_size = p_size, reuse_ptr, sizeof_object); |
| } |
| prefer_in_recvd_out_size = r_size/sizeof_object; |
| return ret; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::size_type |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| size(const void *ptr) const |
| { |
| //We need no synchronization since this block's size is not going |
| //to be modified by anyone else |
| //Obtain the real size of the block |
| return ((size_type)priv_get_block(ptr)->m_size - AllocatedCtrlUnits)*Alignment + UsableByPreviousChunk; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::zero_free_memory() |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| imultiset_iterator ib(m_header.m_imultiset.begin()), ie(m_header.m_imultiset.end()); |
| |
| //Iterate through all blocks obtaining their size |
| while(ib != ie){ |
| //Just clear user the memory part reserved for the user |
| volatile char *ptr = reinterpret_cast<char*>(&*ib) + BlockCtrlBytes; |
| size_type s = (size_type)ib->m_size*Alignment - BlockCtrlBytes; |
| while(s--){ |
| *ptr++ = 0; |
| } |
| |
| //This surprisingly is optimized out by Visual C++ 7.1 in release mode! |
| //std::memset( reinterpret_cast<char*>(&*ib) + BlockCtrlBytes |
| // , 0 |
| // , ib->m_size*Alignment - BlockCtrlBytes); |
| ++ib; |
| } |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_expand_both_sides(boost::interprocess::allocation_type command |
| ,size_type min_size |
| ,size_type &prefer_in_recvd_out_size |
| ,void *reuse_ptr |
| ,bool only_preferred_backwards |
| ,size_type backwards_multiple) |
| { |
| size_type const preferred_size = prefer_in_recvd_out_size; |
| algo_impl_t::assert_alignment(reuse_ptr); |
| if(command & boost::interprocess::expand_fwd){ |
| if(priv_expand(reuse_ptr, min_size, prefer_in_recvd_out_size = preferred_size)) |
| return reuse_ptr; |
| } |
| else{ |
| prefer_in_recvd_out_size = this->size(reuse_ptr); |
| if(prefer_in_recvd_out_size >= preferred_size || prefer_in_recvd_out_size >= min_size) |
| return reuse_ptr; |
| } |
| |
| if(backwards_multiple){ |
| BOOST_ASSERT(0 == (min_size % backwards_multiple)); |
| BOOST_ASSERT(0 == (preferred_size % backwards_multiple)); |
| } |
| |
| if(command & boost::interprocess::expand_bwd){ |
| //Obtain the real size of the block |
| block_ctrl *reuse = priv_get_block(reuse_ptr); |
| |
| //Sanity check |
| algo_impl_t::assert_alignment(reuse); |
| |
| block_ctrl *prev_block; |
| |
| //If the previous block is not free, there is nothing to do |
| if(priv_is_prev_allocated(reuse)){ |
| return 0; |
| } |
| |
| prev_block = priv_prev_block(reuse); |
| BOOST_ASSERT(!priv_is_allocated_block(prev_block)); |
| |
| //Some sanity checks |
| BOOST_ASSERT(prev_block->m_size == reuse->m_prev_size); |
| algo_impl_t::assert_alignment(prev_block); |
| |
| size_type needs_backwards_aligned; |
| size_type lcm; |
| if(!algo_impl_t::calculate_lcm_and_needs_backwards_lcmed |
| ( backwards_multiple |
| , prefer_in_recvd_out_size |
| , only_preferred_backwards ? preferred_size : min_size |
| , lcm, needs_backwards_aligned)){ |
| return 0; |
| } |
| |
| //Check if previous block has enough size |
| if(size_type(prev_block->m_size*Alignment) >= needs_backwards_aligned){ |
| //Now take all next space. This will succeed |
| if(command & boost::interprocess::expand_fwd){ |
| size_type received_size2; |
| if(!priv_expand(reuse_ptr, prefer_in_recvd_out_size, received_size2 = prefer_in_recvd_out_size)){ |
| BOOST_ASSERT(0); |
| } |
| BOOST_ASSERT(prefer_in_recvd_out_size == received_size2); |
| } |
| //We need a minimum size to split the previous one |
| if(prev_block->m_size >= (needs_backwards_aligned/Alignment + BlockCtrlUnits)){ |
| block_ctrl *new_block = reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(reuse) - needs_backwards_aligned); |
| |
| //Free old previous buffer |
| new_block->m_size = |
| AllocatedCtrlUnits + (needs_backwards_aligned + (prefer_in_recvd_out_size - UsableByPreviousChunk))/Alignment; |
| BOOST_ASSERT(new_block->m_size >= BlockCtrlUnits); |
| priv_mark_as_allocated_block(new_block); |
| |
| prev_block->m_size = (reinterpret_cast<char*>(new_block) - |
| reinterpret_cast<char*>(prev_block))/Alignment; |
| BOOST_ASSERT(prev_block->m_size >= BlockCtrlUnits); |
| priv_mark_as_free_block(prev_block); |
| |
| //Update the old previous block in the free blocks tree |
| //If the new size fulfills tree invariants do nothing, |
| //otherwise erase() + insert() |
| { |
| imultiset_iterator prev_block_it(Imultiset::s_iterator_to(*prev_block)); |
| imultiset_iterator was_smaller_it(prev_block_it); |
| if(prev_block_it != m_header.m_imultiset.begin() && |
| (--(was_smaller_it = prev_block_it))->m_size > prev_block->m_size){ |
| m_header.m_imultiset.erase(prev_block_it); |
| m_header.m_imultiset.insert(m_header.m_imultiset.begin(), *prev_block); |
| } |
| } |
| |
| prefer_in_recvd_out_size = needs_backwards_aligned + prefer_in_recvd_out_size; |
| m_header.m_allocated += needs_backwards_aligned; |
| |
| //Check alignment |
| algo_impl_t::assert_alignment(new_block); |
| |
| //If the backwards expansion has remaining bytes in the |
| //first bytes, fill them with a pattern |
| void *p = priv_get_user_buffer(new_block); |
| void *user_ptr = reinterpret_cast<char*>(p); |
| BOOST_ASSERT((static_cast<char*>(reuse_ptr) - static_cast<char*>(user_ptr)) % backwards_multiple == 0); |
| algo_impl_t::assert_alignment(user_ptr); |
| return user_ptr; |
| } |
| //Check if there is no place to create a new block and |
| //the whole new block is multiple of the backwards expansion multiple |
| else if(prev_block->m_size >= needs_backwards_aligned/Alignment && |
| 0 == ((prev_block->m_size*Alignment) % lcm)) { |
| //Erase old previous block, since we will change it |
| m_header.m_imultiset.erase(Imultiset::s_iterator_to(*prev_block)); |
| |
| //Just merge the whole previous block |
| //prev_block->m_size*Alignment is multiple of lcm (and backwards_multiple) |
| prefer_in_recvd_out_size = prefer_in_recvd_out_size + (size_type)prev_block->m_size*Alignment; |
| |
| m_header.m_allocated += (size_type)prev_block->m_size*Alignment; |
| //Now update sizes |
| prev_block->m_size = prev_block->m_size + reuse->m_size; |
| BOOST_ASSERT(prev_block->m_size >= BlockCtrlUnits); |
| priv_mark_as_allocated_block(prev_block); |
| |
| //If the backwards expansion has remaining bytes in the |
| //first bytes, fill them with a pattern |
| void *user_ptr = priv_get_user_buffer(prev_block); |
| BOOST_ASSERT((static_cast<char*>(reuse_ptr) - static_cast<char*>(user_ptr)) % backwards_multiple == 0); |
| algo_impl_t::assert_alignment(user_ptr); |
| return user_ptr; |
| } |
| else{ |
| //Alignment issues |
| } |
| } |
| } |
| return 0; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| deallocate_many(typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::multiallocation_chain &chain) |
| { |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| algo_impl_t::deallocate_many(this, chain); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void * rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_allocate(boost::interprocess::allocation_type command |
| ,size_type limit_size |
| ,size_type &prefer_in_recvd_out_size |
| ,void *&reuse_ptr |
| ,size_type backwards_multiple) |
| { |
| size_type const preferred_size = prefer_in_recvd_out_size; |
| if(command & boost::interprocess::shrink_in_place){ |
| if(!reuse_ptr) return static_cast<void*>(0); |
| bool success = |
| algo_impl_t::shrink(this, reuse_ptr, limit_size, prefer_in_recvd_out_size = preferred_size); |
| return success ? reuse_ptr : 0; |
| } |
| |
| prefer_in_recvd_out_size = 0; |
| |
| if(limit_size > preferred_size) |
| return reuse_ptr = 0, static_cast<void*>(0); |
| |
| //Number of units to request (including block_ctrl header) |
| size_type preferred_units = priv_get_total_units(preferred_size); |
| |
| //Number of units to request (including block_ctrl header) |
| size_type limit_units = priv_get_total_units(limit_size); |
| |
| //Expand in place |
| prefer_in_recvd_out_size = preferred_size; |
| if(reuse_ptr && (command & (boost::interprocess::expand_fwd | boost::interprocess::expand_bwd))){ |
| void *ret = priv_expand_both_sides |
| (command, limit_size, prefer_in_recvd_out_size, reuse_ptr, true, backwards_multiple); |
| if(ret) |
| return ret; |
| } |
| |
| if(command & boost::interprocess::allocate_new){ |
| size_block_ctrl_compare comp; |
| imultiset_iterator it(m_header.m_imultiset.lower_bound(preferred_units, comp)); |
| |
| if(it != m_header.m_imultiset.end()){ |
| return reuse_ptr = 0, this->priv_check_and_allocate |
| (preferred_units, ipcdetail::to_raw_pointer(&*it), prefer_in_recvd_out_size); |
| } |
| |
| if(it != m_header.m_imultiset.begin()&& |
| (--it)->m_size >= limit_units){ |
| return reuse_ptr = 0, this->priv_check_and_allocate |
| (it->m_size, ipcdetail::to_raw_pointer(&*it), prefer_in_recvd_out_size); |
| } |
| } |
| |
| |
| //Now try to expand both sides with min size |
| if(reuse_ptr && (command & (boost::interprocess::expand_fwd | boost::interprocess::expand_bwd))){ |
| return priv_expand_both_sides |
| (command, limit_size, prefer_in_recvd_out_size = preferred_size, reuse_ptr, false, backwards_multiple); |
| } |
| return reuse_ptr = 0, static_cast<void*>(0); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_get_block(const void *ptr) |
| { |
| return const_cast<block_ctrl*> |
| (reinterpret_cast<const block_ctrl*> |
| (reinterpret_cast<const char*>(ptr) - AllocatedCtrlBytes)); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline |
| void *rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_get_user_buffer(const typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *block) |
| { return const_cast<char*>(reinterpret_cast<const char*>(block) + AllocatedCtrlBytes); } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| inline typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::size_type |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_get_total_units(size_type userbytes) |
| { |
| if(userbytes < UsableByPreviousChunk) |
| userbytes = UsableByPreviousChunk; |
| size_type units = ipcdetail::get_rounded_size(userbytes - UsableByPreviousChunk, Alignment)/Alignment + AllocatedCtrlUnits; |
| if(units < BlockCtrlUnits) units = BlockCtrlUnits; |
| return units; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| bool rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>:: |
| priv_expand (void *ptr, const size_type min_size, size_type &prefer_in_recvd_out_size) |
| { |
| size_type const preferred_size = prefer_in_recvd_out_size; |
| //Obtain the real size of the block |
| block_ctrl *block = priv_get_block(ptr); |
| size_type old_block_units = block->m_size; |
| |
| //The block must be marked as allocated and the sizes must be equal |
| BOOST_ASSERT(priv_is_allocated_block(block)); |
| |
| //Put this to a safe value |
| prefer_in_recvd_out_size = (old_block_units - AllocatedCtrlUnits)*Alignment + UsableByPreviousChunk; |
| if(prefer_in_recvd_out_size >= preferred_size || prefer_in_recvd_out_size >= min_size) |
| return true; |
| |
| //Now translate it to Alignment units |
| const size_type min_user_units = algo_impl_t::ceil_units(min_size - UsableByPreviousChunk); |
| const size_type preferred_user_units = algo_impl_t::ceil_units(preferred_size - UsableByPreviousChunk); |
| |
| //Some parameter checks |
| BOOST_ASSERT(min_user_units <= preferred_user_units); |
| |
| block_ctrl *next_block; |
| |
| if(priv_is_allocated_block(next_block = priv_next_block(block))){ |
| return prefer_in_recvd_out_size >= min_size; |
| } |
| algo_impl_t::assert_alignment(next_block); |
| |
| //Is "block" + "next_block" big enough? |
| const size_type merged_units = old_block_units + (size_type)next_block->m_size; |
| |
| //Now get the expansion size |
| const size_type merged_user_units = merged_units - AllocatedCtrlUnits; |
| |
| if(merged_user_units < min_user_units){ |
| prefer_in_recvd_out_size = merged_units*Alignment - UsableByPreviousChunk; |
| return false; |
| } |
| |
| //Now get the maximum size the user can allocate |
| size_type intended_user_units = (merged_user_units < preferred_user_units) ? |
| merged_user_units : preferred_user_units; |
| |
| //These are total units of the merged block (supposing the next block can be split) |
| const size_type intended_units = AllocatedCtrlUnits + intended_user_units; |
| |
| //Check if we can split the next one in two parts |
| if((merged_units - intended_units) >= BlockCtrlUnits){ |
| //This block is bigger than needed, split it in |
| //two blocks, the first one will be merged and |
| //the second's size will be the remaining space |
| BOOST_ASSERT(next_block->m_size == priv_next_block(next_block)->m_prev_size); |
| const size_type rem_units = merged_units - intended_units; |
| |
| //Check if we we need to update the old next block in the free blocks tree |
| //If the new size fulfills tree invariants, we just need to replace the node |
| //(the block start has been displaced), otherwise erase() + insert(). |
| // |
| //This fixup must be done in two parts, because the new next block might |
| //overwrite the tree hook of the old next block. So we first erase the |
| //old if needed and we'll insert the new one after creating the new next |
| imultiset_iterator old_next_block_it(Imultiset::s_iterator_to(*next_block)); |
| const bool size_invariants_broken = |
| (next_block->m_size - rem_units ) < BlockCtrlUnits || |
| (old_next_block_it != m_header.m_imultiset.begin() && |
| (--imultiset_iterator(old_next_block_it))->m_size > rem_units); |
| if(size_invariants_broken){ |
| m_header.m_imultiset.erase(old_next_block_it); |
| } |
| //This is the remaining block |
| block_ctrl *rem_block = ::new(reinterpret_cast<block_ctrl*> |
| (reinterpret_cast<char*>(block) + intended_units*Alignment), boost_container_new_t())block_ctrl; |
| rem_block->m_size = rem_units; |
| algo_impl_t::assert_alignment(rem_block); |
| BOOST_ASSERT(rem_block->m_size >= BlockCtrlUnits); |
| priv_mark_as_free_block(rem_block); |
| |
| //Now the second part of the fixup |
| if(size_invariants_broken) |
| m_header.m_imultiset.insert(m_header.m_imultiset.begin(), *rem_block); |
| else |
| m_header.m_imultiset.replace_node(old_next_block_it, *rem_block); |
| |
| //Write the new length |
| block->m_size = intended_user_units + AllocatedCtrlUnits; |
| BOOST_ASSERT(block->m_size >= BlockCtrlUnits); |
| m_header.m_allocated += (intended_units - old_block_units)*Alignment; |
| } |
| //There is no free space to create a new node: just merge both blocks |
| else{ |
| //Now we have to update the data in the tree |
| m_header.m_imultiset.erase(Imultiset::s_iterator_to(*next_block)); |
| |
| //Write the new length |
| block->m_size = merged_units; |
| BOOST_ASSERT(block->m_size >= BlockCtrlUnits); |
| m_header.m_allocated += (merged_units - old_block_units)*Alignment; |
| } |
| priv_mark_as_allocated_block(block); |
| prefer_in_recvd_out_size = ((size_type)block->m_size - AllocatedCtrlUnits)*Alignment + UsableByPreviousChunk; |
| return true; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_prev_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *ptr) |
| { |
| BOOST_ASSERT(!ptr->m_prev_allocated); |
| return reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(ptr) - ptr->m_prev_size*Alignment); |
| } |
| |
| |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_end_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *first_segment_block) |
| { |
| //The first block's logic is different from the rest of blocks: stores in m_prev_size the absolute |
| //distance with the end block |
| BOOST_ASSERT(first_segment_block->m_prev_allocated); |
| block_ctrl *end_block = reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(first_segment_block) + first_segment_block->m_prev_size*Alignment); |
| (void)end_block; |
| BOOST_ASSERT(end_block->m_allocated == 1); |
| BOOST_ASSERT(end_block->m_size == first_segment_block->m_prev_size); |
| BOOST_ASSERT(end_block > first_segment_block); |
| return end_block; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_first_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *end_segment_block) |
| { |
| //The first block's logic is different from the rest of blocks: stores in m_prev_size the absolute |
| //distance with the end block |
| BOOST_ASSERT(end_segment_block->m_allocated); |
| block_ctrl *first_block = reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(end_segment_block) - end_segment_block->m_size*Alignment); |
| (void)first_block; |
| BOOST_ASSERT(first_block->m_prev_allocated == 1); |
| BOOST_ASSERT(first_block->m_prev_size == end_segment_block->m_size); |
| BOOST_ASSERT(end_segment_block > first_block); |
| return first_block; |
| } |
| |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl * |
| rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_next_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *ptr) |
| { |
| return reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(ptr) + ptr->m_size*Alignment); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| bool rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_is_allocated_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *block) |
| { |
| bool allocated = block->m_allocated != 0; |
| #ifndef NDEBUG |
| if(block != priv_end_block()){ |
| block_ctrl *next_block = reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(block) + block->m_size*Alignment); |
| bool next_block_prev_allocated = next_block->m_prev_allocated != 0; |
| (void)next_block_prev_allocated; |
| BOOST_ASSERT(allocated == next_block_prev_allocated); |
| } |
| #endif |
| return allocated; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| bool rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_is_prev_allocated |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *block) |
| { |
| if(block->m_prev_allocated){ |
| return true; |
| } |
| else{ |
| #ifndef NDEBUG |
| if(block != priv_first_block()){ |
| block_ctrl *prev = priv_prev_block(block); |
| (void)prev; |
| BOOST_ASSERT(!prev->m_allocated); |
| BOOST_ASSERT(prev->m_size == block->m_prev_size); |
| } |
| #endif |
| return false; |
| } |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_mark_as_allocated_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *block) |
| { |
| block->m_allocated = 1; |
| reinterpret_cast<block_ctrl *> |
| (reinterpret_cast<char*>(block)+ block->m_size*Alignment)->m_prev_allocated = 1; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_mark_as_free_block |
| (typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl *block) |
| { |
| block->m_allocated = 0; |
| block_ctrl *next_block = priv_next_block(block); |
| next_block->m_prev_allocated = 0; |
| next_block->m_prev_size = block->m_size; |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> inline |
| void* rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_check_and_allocate |
| (size_type nunits |
| ,typename rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::block_ctrl* block |
| ,size_type &received_size) |
| { |
| size_type upper_nunits = nunits + BlockCtrlUnits; |
| imultiset_iterator it_old = Imultiset::s_iterator_to(*block); |
| algo_impl_t::assert_alignment(block); |
| |
| if (block->m_size >= upper_nunits){ |
| //This block is bigger than needed, split it in |
| //two blocks, the first's size will be "units" and |
| //the second's size "block->m_size-units" |
| size_type block_old_size = block->m_size; |
| block->m_size = nunits; |
| BOOST_ASSERT(block->m_size >= BlockCtrlUnits); |
| |
| //This is the remaining block |
| block_ctrl *rem_block = ::new(reinterpret_cast<block_ctrl*> |
| (reinterpret_cast<char*>(block) + Alignment*nunits), boost_container_new_t())block_ctrl; |
| algo_impl_t::assert_alignment(rem_block); |
| rem_block->m_size = block_old_size - nunits; |
| BOOST_ASSERT(rem_block->m_size >= BlockCtrlUnits); |
| priv_mark_as_free_block(rem_block); |
| |
| imultiset_iterator it_hint; |
| if(it_old == m_header.m_imultiset.begin() |
| || (--imultiset_iterator(it_old))->m_size <= rem_block->m_size){ |
| //option a: slow but secure |
| //m_header.m_imultiset.insert(m_header.m_imultiset.erase(it_old), *rem_block); |
| //option b: Construct an empty node and swap |
| //Imultiset::init_node(*rem_block); |
| //block->swap_nodes(*rem_block); |
| //option c: replace the node directly |
| m_header.m_imultiset.replace_node(Imultiset::s_iterator_to(*it_old), *rem_block); |
| } |
| else{ |
| //Now we have to update the data in the tree |
| m_header.m_imultiset.erase(it_old); |
| m_header.m_imultiset.insert(m_header.m_imultiset.begin(), *rem_block); |
| } |
| |
| } |
| else if (block->m_size >= nunits){ |
| m_header.m_imultiset.erase(it_old); |
| } |
| else{ |
| BOOST_ASSERT(0); |
| return 0; |
| } |
| //We need block_ctrl for deallocation stuff, so |
| //return memory user can overwrite |
| m_header.m_allocated += (size_type)block->m_size*Alignment; |
| received_size = ((size_type)block->m_size - AllocatedCtrlUnits)*Alignment + UsableByPreviousChunk; |
| |
| //Mark the block as allocated |
| priv_mark_as_allocated_block(block); |
| |
| //Clear the memory occupied by the tree hook, since this won't be |
| //cleared with zero_free_memory |
| TreeHook *t = static_cast<TreeHook*>(block); |
| //Just clear the memory part reserved for the user |
| std::size_t tree_hook_offset_in_block = (char*)t - (char*)block; |
| //volatile char *ptr = |
| char *ptr = reinterpret_cast<char*>(block)+tree_hook_offset_in_block; |
| const std::size_t s = BlockCtrlBytes - tree_hook_offset_in_block; |
| std::memset(ptr, 0, s); |
| this->priv_next_block(block)->m_prev_size = 0; |
| return priv_get_user_buffer(block); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::deallocate(void* addr) |
| { |
| if(!addr) return; |
| //----------------------- |
| boost::interprocess::scoped_lock<mutex_type> guard(m_header); |
| //----------------------- |
| return this->priv_deallocate(addr); |
| } |
| |
| template<class MutexFamily, class VoidPointer, std::size_t MemAlignment> |
| void rbtree_best_fit<MutexFamily, VoidPointer, MemAlignment>::priv_deallocate(void* addr) |
| { |
| if(!addr) return; |
| |
| block_ctrl *block = priv_get_block(addr); |
| |
| //The blocks must be marked as allocated and the sizes must be equal |
| BOOST_ASSERT(priv_is_allocated_block(block)); |
| |
| //Check if alignment and block size are right |
| algo_impl_t::assert_alignment(addr); |
| |
| size_type block_old_size = Alignment*(size_type)block->m_size; |
| BOOST_ASSERT(m_header.m_allocated >= block_old_size); |
| |
| //Update used memory count |
| m_header.m_allocated -= block_old_size; |
| |
| //The block to insert in the tree |
| block_ctrl *block_to_insert = block; |
| |
| //Get the next block |
| block_ctrl *const next_block = priv_next_block(block); |
| const bool merge_with_prev = !priv_is_prev_allocated(block); |
| const bool merge_with_next = !priv_is_allocated_block(next_block); |
| |
| //Merge logic. First just update block sizes, then fix free blocks tree |
| if(merge_with_prev || merge_with_next){ |
| //Merge if the previous is free |
| if(merge_with_prev){ |
| //Get the previous block |
| block_to_insert = priv_prev_block(block); |
| block_to_insert->m_size += block->m_size; |
| BOOST_ASSERT(block_to_insert->m_size >= BlockCtrlUnits); |
| } |
| //Merge if the next is free |
| if(merge_with_next){ |
| block_to_insert->m_size += next_block->m_size; |
| BOOST_ASSERT(block_to_insert->m_size >= BlockCtrlUnits); |
| const imultiset_iterator next_it = Imultiset::s_iterator_to(*next_block); |
| if(merge_with_prev){ |
| m_header.m_imultiset.erase(next_it); |
| } |
| else{ |
| m_header.m_imultiset.replace_node(next_it, *block_to_insert); |
| } |
| } |
| |
| //Now try to shortcut erasure + insertion (O(log(N))) with |
| //a O(1) operation if merging does not alter tree positions |
| const imultiset_iterator block_to_check_it = Imultiset::s_iterator_to(*block_to_insert); |
| imultiset_const_iterator next_to_check_it(block_to_check_it), end_it(m_header.m_imultiset.end()); |
| |
| if(++next_to_check_it != end_it && block_to_insert->m_size > next_to_check_it->m_size){ |
| //Block is bigger than next, so move it |
| m_header.m_imultiset.erase(block_to_check_it); |
| m_header.m_imultiset.insert(end_it, *block_to_insert); |
| } |
| else{ |
| //Block size increment didn't violate tree invariants so there is nothing to fix |
| } |
| } |
| else{ |
| m_header.m_imultiset.insert(m_header.m_imultiset.begin(), *block_to_insert); |
| } |
| priv_mark_as_free_block(block_to_insert); |
| } |
| |
| #endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED |
| |
| } //namespace interprocess { |
| } //namespace boost { |
| |
| #include <boost/interprocess/detail/config_end.hpp> |
| |
| #endif //#ifndef BOOST_INTERPROCESS_MEM_ALGO_RBTREE_BEST_FIT_HPP |