Struct ByteArena 

pub struct ByteArena { /* private fields */ }

Append-only byte store addressed by u32 offset. data.len() is the (zero-filled) capacity; cursor is the live high-water mark — bytes [0, cursor) are the appended payloads.

Implementations

impl ByteArena

pub const fn new() -> Self

Empty arena, no allocation until the first append.

pub fn with_capacity(capacity: usize) -> Self

Empty arena pre-grown to capacity so the first appends don’t re-grow.

pub fn append(&mut self, bytes: &[u8]) -> u32

Append bytes, returning the offset they were written at. Grows the backing power-of-two when the bump would overflow capacity.

Panics

Panics if the resulting high-water mark exceeds u32::MAX — the address width of the returned offset. Callers with a bounded window (in-flight bytes ≤ congestion window) never reach this.

pub fn read(&self, offset: u32, len: u32) -> &[u8]

Borrow the len bytes written at offset.

pub fn reset(&mut self)

Reclaim everything: the next append starts at offset 0 again. The backing allocation is retained for reuse. Sound only when no live (offset, len) reference into the arena outlives the reset.

pub fn bytes_used(&self) -> usize

Live bytes appended since the last reset.

pub fn capacity(&self) -> usize

Retained backing capacity in bytes.

pub fn is_empty(&self) -> bool

True when nothing has been appended since the last reset.

Trait Implementations

impl Clone for ByteArena

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ByteArena

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ByteArena

fn default() -> Self

Returns the “default value” for a type.