Crate crossbar 

crossbar

Zero-copy pub/sub over shared memory. URI-addressed. O(1) transfer at any payload size.

Transfers an 8-byte descriptor through a lock-free ring — O(1) regardless of payload. Subscribers read directly from shared memory via Sample — no copy, no serialization, no service discovery layer.

Supported platforms: Linux, macOS, Windows.

Quick Start

use crossbar::*;

// Publisher
let mut pub_ = Publisher::create("prices", Config::default()).unwrap();
let topic = pub_.register("/tick/AAPL").unwrap();

let mut loan = pub_.loan(&topic).unwrap();
loan.set_data(b"hello").unwrap();
loan.publish(); // O(1) — writes 8 bytes to ring

Re-exports

pub use protocol::Config;

pub use protocol::Region;

pub use wait::WaitStrategy;

Modules

error

Error types for shared-memory pub/sub operations.

protocol

Core protocol types and layout constants for crossbar pub/sub.

wait

Wait strategies for blocking receive operations.

Structs

BusSubscriber

A subscriber that reads from a PodBus ring via shared memory.

Channel

Bidirectional shared-memory channel.

DiscoveredTopic

A discovered topic from the global registry.

Loan

A mutable view into a pool block in shared memory.

PinnedLoan

Mutable view into a pinned block in shared memory.

PinnedSample

Near-zero-overhead read reference to a pinned block in shared memory.

PodBus

SPMC broadcast ring for Pod types, backed by shared memory.

Publisher

O(1) zero-copy publisher over shared memory.

Registry

Global topic registry for service discovery.

Sample

Safe zero-copy reference to a published sample in shared memory.

Stream

A subscription to a single topic on a pool-backed pub/sub region.

Subscriber

O(1) zero-copy subscriber for pool-backed pub/sub.

Topic

Handle returned by super::shm::Publisher::register. Identifies a topic for use with super::shm::Publisher::loan.

TypedLoan

Typed mutable loan of a T: Pod value in shared memory.

TypedSample

Typed zero-copy reference to a T: Pod value in shared memory.

Traits

Pod

Plain-old-data types where every bit pattern is valid.

Functions

discover

Discover topics matching a URI pattern.

Type Aliases

IpcErrorDeprecated

Renamed to error::Error.

PinnedGuardDeprecated

Renamed to PinnedSample.

PodBusSubscriberDeprecated

Renamed to BusSubscriber.

PubSubConfigDeprecated

Renamed to Config.

SampleGuardDeprecated

Renamed to Sample.

ShmChannelDeprecated

Renamed to Channel.

ShmLoanDeprecated

Renamed to Loan.

ShmPublisherDeprecated

Renamed to Publisher.

ShmSubscriberDeprecated

Renamed to Subscriber.

SubscriptionDeprecated

Renamed to Stream.

TopicHandleDeprecated

Renamed to Topic.

TypedSampleGuardDeprecated

Renamed to TypedSample.

TypedShmLoanDeprecated

Renamed to TypedLoan.