Struct swim_mem::alloc::Pack

pub struct Pack<'a> { /* fields omitted */ }

Linear allocator for a fixed-size memory block.

A pack allocates space by advancing a pointer into its memory block, similar to stack allocation. Packs only reclaim space when the most recent allocation drops, and when the whole pack drops.

Methods

impl<'a> Pack<'a>

pub fn new(block: Block<'a>) -> &'a Pack<'a>

Constructs a Pack in a memory block.

pub fn from_block(block: Block<'a>, header_size: usize) -> *mut Pack<'a>

Constructs a Pack in a memory block with a reserved header.

Safety

Assumes header_size is large enough to hold the Pack header.

pub fn size(&self) -> usize

Returns the total number of bytes in the memory block, including the pack header.

pub fn free(&self) -> usize

Returns the number of free bytes available for allocation in this Pack.

pub fn live(&self) -> usize

Return the number of live allocations in this Pack.

pub fn used(&self) -> usize

Returns the number of bytes currently allocated in this Pack.

pub unsafe fn as_block(&mut self) -> Block<'a>

Returns the memory block managed by this Pack.

Trait Implementations

impl<'a> Hold<'a> for Pack<'a>

unsafe fn alloc(&self, layout: Layout) -> Result<Block<'a>, HoldError>

Returns an unmanaged pointer to an uninitialized memory block sized and aligned to layout; returns an Err if the allocation fails. The allocated block will have a valid AllocTag in the bytes immediately preceding the block.

unsafe fn dealloc(&self, block: Block<'a>) -> usize

Releases a memory block allocated by this Hold. Returns the number of freed bytes.

unsafe fn resize(
    &self,
    block: Block<'a>,
    layout: Layout
) -> Result<Block<'a>, HoldError>

Attempts to resize in place a memory block allocated by this Hold to fit a new layout. Returns Ok with the resized memory block on success; returns a HoldError on failure.

unsafe fn realloc(
    &self,
    block: Block<'a>,
    layout: Layout
) -> Result<Block<'a>, HoldError>

Attempts to resize a memory block allocated by this Hold to fit a new layout. Returns Ok with the resized memory block on success; returns a HoldError on failure.

impl<'a> Reify<'a, dyn Hold<'a> + 'a> for Pack<'a>

unsafe fn deify(object: &mut (dyn Hold<'a> + 'a))

Initialized the Reified structure at the base address of the object reference to the vtable of the object instance.

unsafe fn reify(base: &'a Reified<dyn Hold<'a> + 'a>) -> &'a (dyn Hold<'a> + 'a)

Returns a polymorphic trait object for the concrete type of the object whose base address equals the address of the passed-in Reified reference.