libstdc++: std::pmr::monotonic_buffer_resource Class Reference

libstdc++

std::pmr::monotonic_buffer_resource Class Reference
Utilities » Memory » Polymorphic memory resources

`#include <memory_resource>`

Inheritance diagram for std::pmr::monotonic_buffer_resource:
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## Public Member Functions
| monotonic_buffer_resource (const monotonic_buffer_resource &)=delete
| monotonic_buffer_resource (memory_resource *__upstream) noexcept
| monotonic_buffer_resource (size_t __initial_size) noexcept
| monotonic_buffer_resource (size_t __initial_size, memory_resource *__upstream) noexcept
| monotonic_buffer_resource (void *__buffer, size_t __buffer_size) noexcept
| monotonic_buffer_resource (void *__buffer, size_t __buffer_size, memory_resource *__upstream) noexcept
void * | allocate (size_t __bytes, size_t __alignment=_S_max_align)
void | deallocate (void *__p, size_t __bytes, size_t __alignment=_S_max_align)
bool | is_equal (const memory_resource &__other) const noexcept
monotonic_buffer_resource & | operator= (const monotonic_buffer_resource &)=delete
void | release () noexcept
memory_resource * | upstream_resource () const noexcept

## Protected Member Functions
void * | do_allocate (size_t __bytes, size_t __alignment) override
void | do_deallocate (void *, size_t, size_t) override
bool | do_is_equal (const memory_resource &__other) const noexcept override

## Detailed Description

A memory resource that allocates from a fixed-size buffer.

The main feature of a pmr::monotonic_buffer_resource is that its do_deallocate does nothing. This makes it very fast because there is no need to manage a free list, and every allocation simply returns a new block of memory, rather than searching for a suitably-sized free block. Because deallocating is a no-op, the amount of memory used by the resource only grows until release() (or the destructor) is called to return all memory to upstream.

A monotonic_buffer_resource can be initialized with a buffer that will be used to satisfy all allocation requests, until the buffer is full. After that a new buffer will be allocated from the upstream resource. By using a stack buffer and pmr::null_memory_resource() as the upstream you can get a memory resource that only uses the stack and never dynamically allocates.

Since
  C++17

Definition at line 339 of file memory_resource.

## Constructor & Destructor Documentation

## ◆ monotonic_buffer_resource() [1/6]

std::pmr::monotonic_buffer_resource::monotonic_buffer_resource | ( | memory_resource * | __upstream | ) |
| inlineexplicitnoexcept

Definition at line 343 of file memory_resource.

## ◆ monotonic_buffer_resource() [2/6]

std::pmr::monotonic_buffer_resource::monotonic_buffer_resource | ( | size_t | __initial_size,
|  | memory_resource * | __upstream )
| inlinenoexcept

Definition at line 348 of file memory_resource.

## ◆ monotonic_buffer_resource() [3/6]

std::pmr::monotonic_buffer_resource::monotonic_buffer_resource | ( | void * | __buffer,
|  | size_t | __buffer_size,
|  | memory_resource * | __upstream )
| inlinenoexcept

Definition at line 358 of file memory_resource.

## ◆ monotonic_buffer_resource() [4/6]

std::pmr::monotonic_buffer_resource::monotonic_buffer_resource | ( |  | ) |
| inlinenoexcept

Definition at line 370 of file memory_resource.

## ◆ monotonic_buffer_resource() [5/6]

std::pmr::monotonic_buffer_resource::monotonic_buffer_resource | ( | size_t | __initial_size | ) |
| inlineexplicitnoexcept

Definition at line 375 of file memory_resource.

## ◆ monotonic_buffer_resource() [6/6]

std::pmr::monotonic_buffer_resource::monotonic_buffer_resource | ( | void * | __buffer,
|  | size_t | __buffer_size )
| inlinenoexcept

Definition at line 379 of file memory_resource.

## Member Function Documentation

## ◆ allocate()

void * std::pmr::memory_resource::allocate | ( | size_t | __bytes,
|  | size_t | __alignment = _S_max_align )
| inlinenodiscardinherited

Definition at line 77 of file memory_resource.h.

## ◆ deallocate()

void std::pmr::memory_resource::deallocate | ( | void * | __p,
|  | size_t | __bytes,
|  | size_t | __alignment = _S_max_align )
| inlineinherited

Definition at line 82 of file memory_resource.h.

## ◆ do_allocate()

void * std::pmr::monotonic_buffer_resource::do_allocate | ( | size_t | __bytes,
|  | size_t | __alignment )
| inlineoverrideprotectedvirtual

Implements std::pmr::memory_resource.

Definition at line 416 of file memory_resource.

## ◆ do_deallocate()

void std::pmr::monotonic_buffer_resource::do_deallocate | ( | void * | ,
|  | size_t | ,
|  | size_t | )
| inlineoverrideprotectedvirtual

Implements std::pmr::memory_resource.

Definition at line 433 of file memory_resource.

## ◆ do_is_equal()

bool std::pmr::monotonic_buffer_resource::do_is_equal | ( | const memory_resource & | __other | ) | const
| inlineoverrideprotectedvirtualnoexcept

Implements std::pmr::memory_resource.

Definition at line 437 of file memory_resource.

## ◆ is_equal()

bool std::pmr::memory_resource::is_equal | ( | const memory_resource & | __other | ) | const
| inlinenodiscardnoexceptinherited

Definition at line 88 of file memory_resource.h.

## ◆ release()

void std::pmr::monotonic_buffer_resource::release | ( |  | ) |
| inlinenoexcept

Definition at line 391 of file memory_resource.

## ◆ upstream_resource()

memory_resource * std::pmr::monotonic_buffer_resource::upstream_resource | ( |  | ) | const
| inlinenoexcept

Definition at line 410 of file memory_resource.

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

- memory_resource