Struct catalyst_entities::Allocator

pub struct Allocator { /* private fields */ }

A simple bump allocator that allocates memory into fixed size chunks.

Implementations

impl Allocator

pub const DEFAULT_CHUNK_SIZE: usize = 2_097_152usize

Something with linux page size

pub fn new(chunk_size: usize) -> Self

Create a new allocator with a chunk size of chunk_size. The constructor by it self does not allocate anything.

pub fn alloc(&mut self, layout: Layout, write_padding: bool) -> NonNull<[u8]>

Allocate a new chunk of memory. This rarely causes system calls if the layout size is small compared to the chunk size. Lifetime of the returned memory is tied to the lifetime of the allocator.

pub unsafe fn clear(&mut self)

Declares all memory freed. Using the pointers after this call is UB.

pub fn frame(&mut self) -> AllocatorFrame<'_>

Creates allocator frame, frame takes snapshot of the allocator and frees subsequent allocations on drop.

impl Allocator

pub unsafe fn grow( &mut self, ptr: NonNull<u8>, previous_layout: Layout, new_layout: Layout ) -> NonNull<[u8]>

Safety

previous_size must be the size of the allocation at ptr. puadding needs to be written for top allocation

pub unsafe fn try_free(&mut self, ptr: NonNull<u8>, layout: Layout) -> bool

try to free the memory at ptr if it is the last allocation in the current chunk

Safety

size mush match the size of the allocation at ptr.

Trait Implementations

impl Default for Allocator

fn default() -> Self

Returns the “default value” for a type.