EVOLUTION-MANAGER

Edit File: pool_resource.hpp

//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2015-2015. 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/container for documentation.
//
//////////////////////////////////////////////////////////////////////////////

#ifndef BOOST_CONTAINER_POOL_RESOURCE_HPP
#define BOOST_CONTAINER_POOL_RESOURCE_HPP

#if defined (_MSC_VER)
#  pragma once 
#endif

#include <boost/container/detail/config_begin.hpp>
#include <boost/container/detail/workaround.hpp>
#include <boost/container/pmr/memory_resource.hpp>
#include <boost/container/detail/block_list.hpp>
#include <boost/container/pmr/pool_options.hpp>

#include <cstddef>

namespace boost {
namespace container {
namespace pmr {

#if !defined(BOOST_CONTAINER_DOXYGEN_INVOKED)

class pool_data_t;

static const std::size_t pool_options_minimum_max_blocks_per_chunk = 1u;
static const std::size_t pool_options_default_max_blocks_per_chunk = 32u;
static const std::size_t pool_options_minimum_largest_required_pool_block =
   memory_resource::max_align > 2*sizeof(void*) ? memory_resource::max_align : 2*sizeof(void*);
static const std::size_t pool_options_default_largest_required_pool_block =
   pool_options_minimum_largest_required_pool_block > 4096u
      ? pool_options_minimum_largest_required_pool_block : 4096u;

#endif   //BOOST_CONTAINER_DOXYGEN_INVOKED

class pool_resource
{
 typedef block_list_base<> block_list_base_t;

pool_options m_options;
   memory_resource&   m_upstream;
   block_list_base_t  m_oversized_list;
   pool_data_t *m_pool_data;
   std::size_t  m_pool_count;

static void priv_limit_option(std::size_t &val, std::size_t min, std::size_t max);
   static std::size_t priv_pool_index(std::size_t block_size);
   static std::size_t priv_pool_block(std::size_t index);

void priv_fix_options();
   void priv_init_pools();
   void priv_constructor_body();

public:

//! Requires: `upstream` is the address of a valid memory resource.
 //!
 //! Effects: Constructs a pool resource object that will obtain memory
 //! from upstream whenever the pool resource is unable to satisfy a memory
 //! request from its own internal data structures. The resulting object will hold
 //! a copy of upstream, but will not own the resource to which upstream points.
 //! [ Note: The intention is that calls to upstream->allocate() will be
 //! substantially fewer than calls to this->allocate() in most cases. - end note 
 //! The behavior of the pooling mechanism is tuned according to the value of
 //! the opts argument.
 //!
 //! Throws: Nothing unless upstream->allocate() throws. It is unspecified if
 //! or under what conditions this constructor calls upstream->allocate().
 pool_resource(const pool_options& opts, memory_resource* upstream) BOOST_NOEXCEPT;

//! Effects: Same as
 //! `pool_resource(pool_options(), get_default_resource())`.
 pool_resource() BOOST_NOEXCEPT;

//! Effects: Same as
 //! `pool_resource(pool_options(), upstream)`.
 explicit pool_resource(memory_resource* upstream) BOOST_NOEXCEPT;

//! Effects: Same as
 //! `pool_resource(opts, get_default_resource())`.
 explicit pool_resource(const pool_options& opts) BOOST_NOEXCEPT;

#if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS) || defined(BOOST_CONTAINER_DOXYGEN_INVOKED)
   pool_resource(const pool_resource&) = delete;
   pool_resource operator=(const pool_resource&) = delete;
   #else
   private:
   pool_resource          (const pool_resource&);
   pool_resource operator=(const pool_resource&);
   public:
   #endif

//! Effects: Calls
 //! `this->release()`.
 virtual ~pool_resource();

//! Effects: Calls Calls `upstream_resource()->deallocate()` as necessary
 //! to release all allocated memory. [ Note: memory is released back to
 //! `upstream_resource()` even if deallocate has not been called for some
 //! of the allocated blocks. - end note ]
 void release();

//! Returns: The value of the upstream argument provided to the
 //! constructor of this object.
 memory_resource* upstream_resource() const;

//! Returns: The options that control the pooling behavior of this resource.
 //! The values in the returned struct may differ from those supplied to the pool
 //! resource constructor in that values of zero will be replaced with
 //! implementation-defined defaults and sizes may be rounded to unspecified granularity.
 pool_options options() const;

public:  //public so that [un]synchronized_pool_resource can use them

//! Returns: A pointer to allocated storage with a size of at least `bytes`.
 //! The size and alignment of the allocated memory shall meet the requirements for
 //! a class derived from `memory_resource`.
 //!
 //! Effects: If the pool selected for a block of size bytes is unable to
 //! satisfy the memory request from its own internal data structures, it will call
 //! `upstream_resource()->allocate()` to obtain more memory. If `bytes` is larger
 //! than that which the largest pool can handle, then memory will be allocated
 //! using `upstream_resource()->allocate()`.
 //!
 //! Throws: Nothing unless `upstream_resource()->allocate()` throws.
 virtual void* do_allocate(std::size_t bytes, std::size_t alignment);

//! Effects: Return the memory at p to the pool. It is unspecified if or under
 //! what circumstances this operation will result in a call to
 //! `upstream_resource()->deallocate()`.
 //!
 //! Throws: Nothing.
 virtual void do_deallocate(void* p, std::size_t bytes, std::size_t alignment);

//! Returns:
 //! `this == dynamic_cast<const pool_resource*>(&other)`.
 virtual bool do_is_equal(const memory_resource& other) const BOOST_NOEXCEPT;

//Non-standard observers
 public:
 //! Returns: The number of pools that will be used in the pool resource.
 //!
 //! Note: Non-standard extension.
 std::size_t pool_count() const;

//! Returns: The index of the pool that will be used to serve the allocation of `bytes`.
 //! from the pool specified by `pool_index`. Returns `pool_count()` if `bytes` is bigger
 //! than `options().largest_required_pool_block` (no pool will be used to serve this).
 //!
 //! Note: Non-standard extension.
 std::size_t pool_index(std::size_t bytes) const;

//! Requires: `pool_idx < pool_index()`
 //!
 //! Returns: The number blocks that will be allocated in the next chunk
 //! from the pool specified by `pool_idx`.
 //!
 //! Note: Non-standard extension.
 std::size_t pool_next_blocks_per_chunk(std::size_t pool_idx) const;

//! Requires: `pool_idx < pool_index()`
 //!
 //! Returns: The number of bytes of the block that the specified `pool_idx` pool manages.
 //!
 //! Note: Non-standard extension.
 std::size_t pool_block(std::size_t pool_idx) const;

//! Requires: `pool_idx < pool_index()`
 //!
 //! Returns: The number of blocks that the specified `pool_idx` pool has cached
 //! and will be served without calling the upstream_allocator.
 //!
 //! Note: Non-standard extension.
 std::size_t pool_cached_blocks(std::size_t pool_idx) const;
};

}  //namespace pmr {
}  //namespace container {
}  //namespace boost {

#include <boost/container/detail/config_end.hpp>

#endif   //BOOST_CONTAINER_POOL_RESOURCE_HPP