20 Memory management library [mem]

20.4 Memory resources [mem.res]

20.4.6 Class monotonic_buffer_resource [mem.res.monotonic.buffer] Members [mem.res.monotonic.buffer.mem]

void release();
Effects: Calls upstream_rsrc->deallocate() as necessary to release all allocated memory.
Resets current_buffer and next_buffer_size to their initial values at construction.
[Note 1: 
The memory is released back to upstream_rsrc even if some blocks that were allocated from *this have not been deallocated from *this.
— end note]
memory_resource* upstream_resource() const;
Returns: The value of upstream_rsrc.
void* do_allocate(size_t bytes, size_t alignment) override;
Effects: If the unused space in current_buffer can fit a block with the specified bytes and alignment, then allocate the return block from current_buffer; otherwise set current_buffer to upstream_rsrc->allocate(n, m), where n is not less than max(bytes, next_buffer_size) and m is not less than alignment, and increase next_buffer_size by an implementation-defined growth factor (which need not be integral), then allocate the return block from the newly-allocated current_buffer.
Returns: A pointer to allocated storage ([basic.stc.dynamic.allocation]) with a size of at least bytes.
The size and alignment of the allocated memory shall meet the requirements for a class derived from memory_resource ([mem.res.class]).
Throws: Nothing unless upstream_rsrc->allocate() throws.
void do_deallocate(void* p, size_t bytes, size_t alignment) override;
Effects: None.
Throws: Nothing.
Remarks: Memory used by this resource increases monotonically until its destruction.
bool do_is_equal(const memory_resource& other) const noexcept override;
Returns: this == &other.