make_persistent_array.hpp File Reference

Persistent_ptr allocation functions for arrays. More...

#include <libpmemobj++/allocation_flag.hpp>
#include <libpmemobj++/detail/array_traits.hpp>
#include <libpmemobj++/detail/check_persistent_ptr_array.hpp>
#include <libpmemobj++/detail/common.hpp>
#include <libpmemobj++/detail/life.hpp>
#include <libpmemobj++/detail/variadic.hpp>
#include <libpmemobj++/pexceptions.hpp>
#include <libpmemobj/tx_base.h>
#include <cassert>
#include <limits>

Go to the source code of this file.

Namespaces
	pmem
	A persistent version of concurrent hash map implementation Ref: https://arxiv.org/abs/1509.02235.

Functions
template<typename T >
detail::pp_if_array< T >::type	pmem::obj::make_persistent (std::size_t N, allocation_flag flag=allocation_flag::none())
	Transactionally allocate and construct an array of objects of type T. More...
template<typename T >
detail::pp_if_size_array< T >::type	pmem::obj::make_persistent (allocation_flag flag=allocation_flag::none())
	Transactionally allocate and construct an array of objects of type T. More...
template<typename T >
void	pmem::obj::delete_persistent (typename detail::pp_if_array< T >::type ptr, std::size_t N)
	Transactionally free an array of objects of type T held in a persistent_ptr. More...
template<typename T >
void	pmem::obj::delete_persistent (typename detail::pp_if_size_array< T >::type ptr)
	Transactionally free an array of objects of type T held in a persistent_ptr. More...

Detailed Description

Persistent_ptr allocation functions for arrays.

The typical usage examples would be:

#include <fcntl.h>
#include <libpmemobj++/make_persistent_array.hpp>
#include <libpmemobj++/p.hpp>
#include <libpmemobj++/persistent_ptr.hpp>
#include <libpmemobj++/pool.hpp>
#include <libpmemobj++/transaction.hpp>
 
using namespace pmem::obj;
 
void
make_persistent_array_example()
{
 
    struct compound_type {
 
        compound_type() : some_variable(0), some_other_variable(0)
        {
        }
 
        void
        set_some_variable(int val)
        {
            some_variable = val;
        }
 
        p<int> some_variable;
        p<double> some_other_variable;
    };
 
    // pool root structure
    struct root {
        persistent_ptr<compound_type[]> comp; //
    };
 
    // create a pmemobj pool
    auto pop = pool<root>::create("poolfile", "layout", PMEMOBJ_MIN_POOL);
    auto proot = pop.root();
 
    // typical usage schemes
    transaction::run(pop, [&] {
        // allocate an array of 20 objects - compound_type must be
        // default constructible
        proot->comp = make_persistent<compound_type[]>(20);
        // another allocation method
        auto arr1 = make_persistent<compound_type[3]>();
 
        // transactionally delete arrays , ~compound_type() is called
        delete_persistent<compound_type[]>(proot->comp, 20);
        delete_persistent<compound_type[3]>(arr1);
    });
 
    // throws an transaction_scope_error exception
    auto arr1 = make_persistent<compound_type[3]>();
    delete_persistent<compound_type[3]>(arr1);
}

Function Documentation

delete_persistent() [1/2]

template<typename T >

void pmem::obj::delete_persistent	(	typename detail::pp_if_array< T >::type	ptr,
		std::size_t	N
	)

Transactionally free an array of objects of type T held in a persistent_ptr.

This function can be used to transactionally free an array of objects. Calls the objects' destructors before freeing memory. This overload only participates in overload resolution if T is an array.

Parameters

[in,out]	ptr	persistent pointer to an array of objects.
[in]	N	the size of the array.

Exceptions

transaction_scope_error	if called outside of an active transaction
transaction_free_error	on transactional free failure.

delete_persistent() [2/2]

template<typename T >

void pmem::obj::delete_persistent

(

typename detail::pp_if_size_array< T >::type

ptr

)

Transactionally free an array of objects of type T held in a persistent_ptr.

This function can be used to transactionally free an array of objects. Calls the objects' destructors before freeing memory. This overload only participates in overload resolution if T is an array.

Parameters

[in,out]

ptr

persistent pointer to an array of objects.

Exceptions

transaction_scope_error	if called outside of an active transaction
transaction_free_error	on transactional free failure.

make_persistent() [1/2]

template<typename T >

detail::pp_if_size_array<T>::type pmem::obj::make_persistent

(

allocation_flag

flag = allocation_flag::none()

)

Transactionally allocate and construct an array of objects of type T.

This function can be used to transactionally allocate an array. This overload only participates in overload resolution if T is an array.

Parameters

[in]

flag

affects behaviour of allocator

Returns

persistent_ptr<T[N]> on success

Exceptions

transaction_scope_error	if called outside of an active transaction
transaction_alloc_error	on transactional allocation failure.
rethrow	exception from T constructor

make_persistent() [2/2]

template<typename T >

detail::pp_if_array<T>::type pmem::obj::make_persistent	(	std::size_t	N,
		allocation_flag	flag = allocation_flag::none()
	)

Transactionally allocate and construct an array of objects of type T.

This function can be used to transactionally allocate an array. This overload only participates in overload resolution if T is an array.

Parameters

[in]	N	the number of array elements.
[in]	flag	affects behaviour of allocator

Returns

persistent_ptr<T[]> on success

Exceptions

transaction_scope_error	if called outside of an active transaction
transaction_alloc_error	on transactional allocation failure.
rethrow	exception from T constructor