A simple first-fit MultiBufAllocator. More...

#include <simple_allocator.h>

Inheritance diagram for pw::multibuf::SimpleAllocator:

Public Member Functions
	SimpleAllocator (ByteSpan data_area, pw::allocator::Allocator &metadata_alloc, size_t alignment=1)

Public Member Functions inherited from pw::multibuf::MultiBufAllocator
	MultiBufAllocator (MultiBufAllocator &)=delete
	``MultiBufAllocator` is not copyable or movable.

MultiBufAllocator &	operator= (MultiBufAllocator &)=delete

	MultiBufAllocator (MultiBufAllocator &&)=delete

MultiBufAllocator &	operator= (MultiBufAllocator &&)=delete

std::optional< MultiBuf >	Allocate (size_t size)

std::optional< MultiBuf >	Allocate (size_t min_size, size_t desired_size)

std::optional< MultiBuf >	AllocateContiguous (size_t size)

std::optional< MultiBuf >	AllocateContiguous (size_t min_size, size_t desired_size)

std::optional< size_t >	GetBackingCapacity ()

Private Member Functions
pw::Result< MultiBuf >	DoAllocate (size_t min_size, size_t desired_size, ContiguityRequirement contiguity_requirement) final

std::optional< size_t >	DoGetBackingCapacity () final

Friends
class	internal::LinkedRegionTracker

Additional Inherited Members
Protected Member Functions inherited from pw::multibuf::MultiBufAllocator
void	MoreMemoryAvailable (size_t size_available, size_t contiguous_size_available)

Detailed Description

A simple first-fit MultiBufAllocator.

Constructor & Destructor Documentation

◆ SimpleAllocator()

pw::multibuf::SimpleAllocator::SimpleAllocator	(	ByteSpan	data_area,
		pw::allocator::Allocator &	metadata_alloc,
		size_t	alignment = `1`
	)

Creates a new SimpleAllocator.

Parameters

[in]	data_area	The region to use for storing chunk memory.
[in]	metadata_alloc	The allocator to use for metadata tracking the in-use regions. This allocator must be thread-safe if the resulting buffers may travel to another thread. `SynchronizedAllocator` can be used to create a thread-safe allocator from a non-thread-safe allocator.
[in]	alignment	The alignment to use. All chunks allocated by this allocator will start aligned with the specified alignment. The alignment can change if the prefix Chunk methods are used. The supplied `data_area` must be aligned (both start and end) to the specified alignment. Defaults to 1.

Member Function Documentation

◆ DoAllocate()

pw::Result< MultiBuf > pw::multibuf::SimpleAllocator::DoAllocate	(	size_t	min_size,
		size_t	desired_size,
		ContiguityRequirement	contiguity_requirement
	)

finalprivatevirtual

Attempts to allocate a MultiBuf of at least min_size bytes and at most desired_size bytes.

Returns

embed:rst:leading-asterisk
 
* 
*  .. pw-status-codes::
* 
*     OK: Returns the buffer if the allocation was successful.
* 
*     RESOURCE_EXHAUSTED: Insufficient memory is available currently.
* 
*     OUT_OF_RANGE: This amount of memory will not become possible to
*     allocate in the future, or this allocator is unable to signal via
*     ``MoreMemoryAvailable`` (this will result in asynchronous allocations
*     failing immediately on OOM).
* 
*

Implements pw::multibuf::MultiBufAllocator.

◆ DoGetBackingCapacity()

std::optional< size_t > pw::multibuf::SimpleAllocator::DoGetBackingCapacity ( )

inlinefinalprivatevirtual

Returns the total amount of memory provided by this object.

This is an optional method. Some memory providers may not have an easily defined capacity, e.g. the system allocator.

Return values

the	total memory if known.
``nullopt_t``	if the total memory is not knowable.

Implements pw::multibuf::MultiBufAllocator.

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

pw_multibuf/public/pw_multibuf/simple_allocator.h

Public Member Functions

Private Member Functions