Struct PubSubRing 

pub struct PubSubRing { /* private fields */ }

One-producer many-subscriber broadcast ring with per-subscriber positions.

Implementations

impl PubSubRing

pub fn create_anon(capacity: usize) -> Result<Self>

Construct an anonymous in-process pub/sub ring.

pub fn create(path: impl AsRef<Path>, capacity: usize) -> Result<Self>

Construct a file-backed pub/sub ring. Cross-process via the OS page cache.

pub fn open(path: impl AsRef<Path>, expected_capacity: usize) -> Result<Self>

Open an existing file-backed pub/sub ring. Validates magic

• capacity.

pub fn create_from_shm(shm: ShmFile, capacity: usize) -> Result<Self>

Construct a fresh pub/sub ring on top of a named RAM-resident shared-memory backing.

pub fn open_from_shm(shm: ShmFile, expected_capacity: usize) -> Result<Self>

Open an existing named ShmFs-backed pub/sub ring.

pub fn head(&self) -> u64

Producer’s published head. Equals the next position that will be assigned to a publish call.

pub fn capacity(&self) -> usize

Capacity in slots (always a power of 2).

pub fn publish(&self, payload: &[u8]) -> u64

Publish one payload. Returns the absolute position assigned to this item. Caller MUST be the single producer.

pub fn read_at( &self, position: u64, out: &mut [u8], ) -> Result<(), PubSubReadError>

Read the payload at absolute position. The subscriber supplies a buffer of at least PUBSUB_PAYLOAD_BYTES.

Returns Ok(()) on success (payload copied into out), Err(Pending) when the position has not been published yet, Err(Lost) when the slot has wrapped past position.

Trait Implementations

impl Send for PubSubRing

impl Sync for PubSubRing