pstore::storage Class Reference

Classes
struct	copy_from_store_traits
struct	copy_to_store_traits

Public Types
using	region_container = std::vector< region::memory_mapper_ptr >

Public Member Functions
	PSTORE_STATIC_ASSERT (full_region_size % min_region_size==0)
template<typename File >
	storage (std::shared_ptr< File > const &file, std::unique_ptr< system_page_size_interface > &&page_size, std::unique_ptr< region::factory > &&region_factory)
template<typename File >
	storage (std::shared_ptr< File > const &file)
file::file_base *	file () noexcept
file::file_base const *	file () const noexcept
void	map_bytes (std::uint64_t new_size)
void	update_master_pointers (std::size_t old_length)
	Called to add newly created memory-mapped regions to the segment address table. More...
template<typename Traits , typename Function >
void	copy (address addr, std::size_t size, typename Traits::temp_pointer p, Function copier) const
	This function performs the bulk of the work of creating a "shadow" block when a request spans more than one memory-mapped region (or when PSTORE_ALWAYS_SPANNING is enabled). More...
bool	request_spans_regions (address const &addr, std::size_t size) const noexcept
	Returns true if the given address range "spans" more than one region. More...
void	protect (address first, address last)
	Marks the address range [first, last) as read-only.
region_container const &	regions () const
std::shared_ptr< void const >	segment_base (address::segment_type const segment) const noexcept
std::shared_ptr< void > const &	segment_base (address::segment_type const segment) noexcept
std::shared_ptr< void const >	address_to_pointer (address const addr) const noexcept
std::shared_ptr< void >	address_to_pointer (address const addr) noexcept
template<typename T >
std::shared_ptr< T const >	address_to_pointer (typed_address< T > addr) const noexcept
template<typename T >
std::shared_ptr< T >	address_to_pointer (typed_address< T > addr) noexcept

Static Public Attributes
static auto constexpr	full_region_size = UINT64_C (1) << 32U
static auto constexpr	min_region_size = UINT64_C (1) << 22U

Member Function Documentation

copy()

template<typename Traits , typename Function >

void pstore::storage::copy	(	address	addr,
		std::size_t	size,
		typename Traits::temp_pointer	p,
		Function	copier
	)		const

This function performs the bulk of the work of creating a "shadow" block when a request spans more than one memory-mapped region (or when PSTORE_ALWAYS_SPANNING is enabled).

It breaks the data into a series of copies (each read or writing as much data as possible) and calls the provided "copier" function to perform the actual copy. This same function is used to copy data from the store into a newly allocated block, and to copy from a contiguous block back to the store.

The template traits argument controls the direction of copy: either copy_from_store_traits or copy_to_store_traits may be used.

Parameters

addr	The store address of the data to be copied.
size	The number of bytes to be copied.
p	A pointer to a block of memory of at least 'size' bytes.
copier	A function that will perform the actual copy. The expected type of the function's arguments are controlled by the 'traits' template argument. The function will be passed 3 arguments: Traits::in_store_pointer: An address lying within the data store. Traits::temp_pointer: A pointer within the memory block given by [p,p+size). std::uint64_t: The number of bytes to be copied.

request_spans_regions()

bool pstore::storage::request_spans_regions ( address const &  addr, std::size_t  size  ) const

inlinenoexcept

Returns true if the given address range "spans" more than one region.

Note

The PSTORE_ALWAYS_SPANNING configure-time setting can cause this function to always return true.

We expect addr and size to have been checked for sanity by the caller.

Parameters

addr	The start of the address range to be considered.
size	The size of the address range to be considered.

Returns

true if the given address range "spans" more than one region.

segment_base()

std::shared_ptr<void const> pstore::storage::segment_base ( address::segment_type const  segment ) const

inlinenoexcept

Returns the base address of a segment given its index.

Parameters

segment

The segment number whose base address it to be returned. The segment number must lie within the memory mapped regions.

update_master_pointers()

void pstore::storage::update_master_pointers

(

std::size_t

old_length

)

Called to add newly created memory-mapped regions to the segment address table.

This happens when the file is initially opened, and when it is grown by calling allocate().

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The documentation for this class was generated from the following files:

• include/pstore/core/storage.hpp
• lib/core/storage.cpp