boost/container/allocator.hpp
//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2007-2013. 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_ALLOCATOR_HPP
#define BOOST_CONTAINER_ALLOCATOR_HPP
#ifndef BOOST_CONFIG_HPP
# include <boost/config.hpp>
#endif
#if defined(BOOST_HAS_PRAGMA_ONCE)
# pragma once
#endif
#include <boost/container/detail/config_begin.hpp>
#include <boost/container/detail/workaround.hpp>
#include <boost/container/container_fwd.hpp>
#include <boost/container/detail/version_type.hpp>
#include <boost/container/throw_exception.hpp>
#include <boost/container/detail/dlmalloc.hpp>
#include <boost/container/detail/multiallocation_chain.hpp>
#include <boost/static_assert.hpp>
#include <cstddef>
#include <cassert>
//!\file
namespace boost {
namespace container {
#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
template<unsigned Version, unsigned int AllocationDisableMask>
class allocator<void, Version, AllocationDisableMask>
{
typedef allocator<void, Version, AllocationDisableMask> self_t;
public:
typedef void value_type;
typedef void * pointer;
typedef const void* const_pointer;
typedef int & reference;
typedef const int & const_reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef boost::container::dtl::
version_type<self_t, Version> version;
#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
typedef boost::container::dtl::
basic_multiallocation_chain<void*> multiallocation_chain;
#endif //#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
//!Obtains an allocator that allocates
//!objects of type T2
template<class T2>
struct rebind
{
typedef allocator< T2
#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
, Version, AllocationDisableMask
#endif
> other;
};
//!Default constructor
//!Never throws
allocator()
{}
//!Constructor from other allocator.
//!Never throws
allocator(const allocator &)
{}
//!Constructor from related allocator.
//!Never throws
template<class T2>
allocator(const allocator<T2, Version, AllocationDisableMask> &)
{}
};
#endif //#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
//! This class is an extended STL-compatible that offers advanced allocation mechanism
//!(in-place expansion, shrinking, burst-allocation...)
//!
//! This allocator is a wrapper around a modified DLmalloc.
//! If Version is 1, the allocator is a STL conforming allocator. If Version is 2,
//! the allocator offers advanced expand in place and burst allocation capabilities.
//!
//! AllocationDisableMask works only if Version is 2 and it can be an inclusive OR
//! of allocation types the user wants to disable.
template< class T
, unsigned Version BOOST_CONTAINER_DOCONLY(=2)
, unsigned int AllocationDisableMask BOOST_CONTAINER_DOCONLY(=0)>
class allocator
{
typedef unsigned int allocation_type;
#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
private:
//Self type
typedef allocator<T, Version, AllocationDisableMask> self_t;
//Not assignable from related allocator
template<class T2, unsigned int Version2, unsigned int AllocationDisableMask2>
allocator& operator=(const allocator<T2, Version2, AllocationDisableMask2>&);
static const unsigned int ForbiddenMask =
BOOST_CONTAINER_ALLOCATE_NEW | BOOST_CONTAINER_EXPAND_BWD | BOOST_CONTAINER_EXPAND_FWD ;
//The mask can't disable all the allocation types
BOOST_STATIC_ASSERT(( (AllocationDisableMask & ForbiddenMask) != ForbiddenMask ));
//The mask is only valid for version 2 allocators
BOOST_STATIC_ASSERT(( Version != 1 || (AllocationDisableMask == 0) ));
#endif //#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
public:
typedef T value_type;
typedef T * pointer;
typedef const T * const_pointer;
typedef T & reference;
typedef const T & const_reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef boost::container::dtl::
version_type<self_t, Version> version;
#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
typedef boost::container::dtl::
basic_multiallocation_chain<void*> void_multiallocation_chain;
typedef boost::container::dtl::
transform_multiallocation_chain
<void_multiallocation_chain, T> multiallocation_chain;
#endif //#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
//!Obtains an allocator that allocates
//!objects of type T2
template<class T2>
struct rebind
{
typedef allocator<T2, Version, AllocationDisableMask> other;
};
//!Default constructor
//!Never throws
allocator() BOOST_NOEXCEPT_OR_NOTHROW
{}
//!Constructor from other allocator.
//!Never throws
allocator(const allocator &) BOOST_NOEXCEPT_OR_NOTHROW
{}
//!Constructor from related allocator.
//!Never throws
template<class T2>
allocator(const allocator<T2
#ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
, Version, AllocationDisableMask
#endif
> &) BOOST_NOEXCEPT_OR_NOTHROW
{}
//!Allocates memory for an array of count elements.
//!Throws bad_alloc if there is no enough memory
//!If Version is 2, this allocated memory can only be deallocated
//!with deallocate() or (for Version == 2) deallocate_many()
BOOST_CONTAINER_ATTRIBUTE_NODISCARD pointer allocate(size_type count, const void * hint= 0)
{
(void)hint;
if(count > size_type(-1)/(2u*sizeof(T)))
boost::container::throw_bad_alloc();
void *ret = dlmalloc_malloc(count*sizeof(T));
if(!ret)
boost::container::throw_bad_alloc();
return static_cast<pointer>(ret);
}
//!Deallocates previously allocated memory.
//!Never throws
BOOST_CONTAINER_FORCEINLINE void deallocate(pointer ptr, size_type) BOOST_NOEXCEPT_OR_NOTHROW
{ dlmalloc_free(ptr); }
//!Returns the maximum number of elements that could be allocated.
//!Never throws
BOOST_CONTAINER_FORCEINLINE size_type max_size() const BOOST_NOEXCEPT_OR_NOTHROW
{ return size_type(-1)/(2u*sizeof(T)); }
//!Swaps two allocators, does nothing
//!because this allocator is stateless
BOOST_CONTAINER_FORCEINLINE friend void swap(self_t &, self_t &) BOOST_NOEXCEPT_OR_NOTHROW
{}
//!An allocator always compares to true, as memory allocated with one
//!instance can be deallocated by another instance
BOOST_CONTAINER_ATTRIBUTE_NODISCARD
friend bool operator==(const allocator &, const allocator &) BOOST_NOEXCEPT_OR_NOTHROW
{ return true; }
//!An allocator always compares to false, as memory allocated with one
//!instance can be deallocated by another instance
BOOST_CONTAINER_ATTRIBUTE_NODISCARD BOOST_CONTAINER_FORCEINLINE
friend bool operator!=(const allocator &, const allocator &) BOOST_NOEXCEPT_OR_NOTHROW
{ return false; }
//!An advanced function that offers in-place expansion shrink to fit and new allocation
//!capabilities. Memory allocated with this function can only be deallocated with deallocate()
//!or deallocate_many().
//!This function is available only with Version == 2
BOOST_CONTAINER_ATTRIBUTE_NODISCARD pointer allocation_command(allocation_type command,
size_type limit_size,
size_type &prefer_in_recvd_out_size,
pointer &reuse)
{
BOOST_STATIC_ASSERT(( Version > 1 ));
const allocation_type mask(AllocationDisableMask);
command &= ~mask;
pointer ret = this->priv_allocation_command(command, limit_size, prefer_in_recvd_out_size, reuse);
if(!ret && !(command & BOOST_CONTAINER_NOTHROW_ALLOCATION))
boost::container::throw_bad_alloc();
return ret;
}
//!Returns maximum the number of objects the previously allocated memory
//!pointed by p can hold.
//!Memory must not have been allocated with
//!allocate_one or allocate_individual.
//!This function is available only with Version == 2
BOOST_CONTAINER_ATTRIBUTE_NODISCARD size_type size(pointer p) const BOOST_NOEXCEPT_OR_NOTHROW
{
BOOST_STATIC_ASSERT(( Version > 1 ));
return dlmalloc_size(p);
}
//!Allocates just one object. Memory allocated with this function
//!must be deallocated only with deallocate_one().
//!Throws bad_alloc if there is no enough memory
//!This function is available only with Version == 2
BOOST_CONTAINER_ATTRIBUTE_NODISCARD BOOST_CONTAINER_FORCEINLINE pointer allocate_one()
{
BOOST_STATIC_ASSERT(( Version > 1 ));
return this->allocate(1);
}
//!Allocates many elements of size == 1.
//!Elements must be individually deallocated with deallocate_one()
//!This function is available only with Version == 2
BOOST_CONTAINER_FORCEINLINE void allocate_individual(std::size_t num_elements, multiallocation_chain &chain)
{
BOOST_STATIC_ASSERT(( Version > 1 ));
this->allocate_many(1, num_elements, chain);
}
//!Deallocates memory previously allocated with allocate_one().
//!You should never use deallocate_one to deallocate memory allocated
//!with other functions different from allocate_one() or allocate_individual.
//Never throws
void deallocate_one(pointer p) BOOST_NOEXCEPT_OR_NOTHROW
{
BOOST_STATIC_ASSERT(( Version > 1 ));
return this->deallocate(p, 1);
}
//!Deallocates memory allocated with allocate_one() or allocate_individual().
//!This function is available only with Version == 2
BOOST_CONTAINER_FORCEINLINE
void deallocate_individual(multiallocation_chain &chain) BOOST_NOEXCEPT_OR_NOTHROW
{
BOOST_STATIC_ASSERT(( Version > 1 ));
return this->deallocate_many(chain);
}
//!Allocates many elements of size elem_size.
//!Elements must be individually deallocated with deallocate()
//!This function is available only with Version == 2
void allocate_many(size_type elem_size, std::size_t n_elements, multiallocation_chain &chain)
{
BOOST_STATIC_ASSERT(( Version > 1 ));
dlmalloc_memchain ch;
BOOST_CONTAINER_MEMCHAIN_INIT(&ch);
if(!dlmalloc_multialloc_nodes(n_elements, elem_size*sizeof(T), BOOST_CONTAINER_DL_MULTIALLOC_DEFAULT_CONTIGUOUS, &ch)){
boost::container::throw_bad_alloc();
}
chain.incorporate_after(chain.before_begin()
,(T*)BOOST_CONTAINER_MEMCHAIN_FIRSTMEM(&ch)
,(T*)BOOST_CONTAINER_MEMCHAIN_LASTMEM(&ch)
,BOOST_CONTAINER_MEMCHAIN_SIZE(&ch) );
/*
if(!dlmalloc_multialloc_nodes(n_elements, elem_size*sizeof(T), BOOST_CONTAINER_DL_MULTIALLOC_DEFAULT_CONTIGUOUS, reinterpret_cast<dlmalloc_memchain *>(&chain))){
boost::container::throw_bad_alloc();
}*/
}
//!Allocates n_elements elements, each one of size elem_sizes[i]
//!Elements must be individually deallocated with deallocate()
//!This function is available only with Version == 2
void allocate_many(const size_type *elem_sizes, size_type n_elements, multiallocation_chain &chain)
{
BOOST_STATIC_ASSERT(( Version > 1 ));
dlmalloc_memchain ch;
BOOST_CONTAINER_MEMCHAIN_INIT(&ch);
if(!dlmalloc_multialloc_arrays(n_elements, elem_sizes, sizeof(T), BOOST_CONTAINER_DL_MULTIALLOC_DEFAULT_CONTIGUOUS, &ch)){
boost::container::throw_bad_alloc();
}
chain.incorporate_after(chain.before_begin()
,(T*)BOOST_CONTAINER_MEMCHAIN_FIRSTMEM(&ch)
,(T*)BOOST_CONTAINER_MEMCHAIN_LASTMEM(&ch)
,BOOST_CONTAINER_MEMCHAIN_SIZE(&ch) );
/*
if(!dlmalloc_multialloc_arrays(n_elements, elem_sizes, sizeof(T), BOOST_CONTAINER_DL_MULTIALLOC_DEFAULT_CONTIGUOUS, reinterpret_cast<dlmalloc_memchain *>(&chain))){
boost::container::throw_bad_alloc();
}*/
}
//!Deallocates several elements allocated by
//!allocate_many(), allocate(), or allocation_command().
//!This function is available only with Version == 2
void deallocate_many(multiallocation_chain &chain) BOOST_NOEXCEPT_OR_NOTHROW
{
BOOST_STATIC_ASSERT(( Version > 1 ));
dlmalloc_memchain ch;
void *beg(&*chain.begin()), *last(&*chain.last());
size_t size(chain.size());
BOOST_CONTAINER_MEMCHAIN_INIT_FROM(&ch, beg, last, size);
dlmalloc_multidealloc(&ch);
//dlmalloc_multidealloc(reinterpret_cast<dlmalloc_memchain *>(&chain));
}
private:
pointer priv_allocation_command
(allocation_type command, std::size_t limit_size
,size_type &prefer_in_recvd_out_size
,pointer &reuse_ptr)
{
std::size_t const preferred_size = prefer_in_recvd_out_size;
dlmalloc_command_ret_t ret = {0 , 0};
if((limit_size > this->max_size()) | (preferred_size > this->max_size())){
return pointer();
}
std::size_t l_size = limit_size*sizeof(T);
std::size_t p_size = preferred_size*sizeof(T);
std::size_t r_size;
{
void* reuse_ptr_void = reuse_ptr;
ret = dlmalloc_allocation_command(command, sizeof(T), l_size, p_size, &r_size, reuse_ptr_void);
reuse_ptr = ret.second ? static_cast<T*>(reuse_ptr_void) : 0;
}
prefer_in_recvd_out_size = r_size/sizeof(T);
return (pointer)ret.first;
}
};
} //namespace container {
} //namespace boost {
#include <boost/container/detail/config_end.hpp>
#endif //BOOST_CONTAINER_ALLOCATOR_HPP