Module common 

One-shot channel implementations for single-use value transfer

This module provides two variants of one-shot channels optimized for different use cases:

一次性通道实现，用于单次值传递

此模块提供两种针对不同使用场景优化的一次性通道变体：

Variants | 变体

lite - Lightweight state-based oneshot

Optimized for small copyable states that can be encoded as u8. Zero heap allocation for the value itself (stored in AtomicU8). Perfect for completion notifications, simple enums, and boolean states.

为可编码为 u8 的小型可复制状态优化。 值本身零堆分配（存储在 AtomicU8 中）。 非常适合完成通知、简单枚举和布尔状态。

Use cases | 使用场景:

• Task completion notification (unit type ())
• Small state machines (custom enums with State trait)
• Boolean flags and simple status codes

Example:

use lite_sync::oneshot::lite::{Sender, error::RecvError};

let (sender, receiver) = Sender::<()>::new();

tokio::spawn(async move {
    // ... do work ...
    sender.send(());
});

receiver.await; // Wait for completion

generic - Generic value transfer oneshot

Supports arbitrary types with zero extra heap allocation for the value. Uses UnsafeCell<MaybeUninit<T>> + AtomicU8 for lock-free value transfer. Value is stored directly in the structure, avoiding Box allocation. Ideal for transferring ownership of any data between tasks.

支持任意类型，值无需额外堆分配。 使用 UnsafeCell<MaybeUninit<T>> + AtomicU8 实现无锁值传递。 值直接存储在结构体中，避免 Box 分配。 非常适合在任务间传递任意数据的所有权。

Use cases | 使用场景:

• Request-response patterns with complex types
• Transferring ownership of heap-allocated data
• Sending results of arbitrary computations

Example:

use lite_sync::oneshot::generic::Sender;

let (sender, receiver) = Sender::<String>::new();

tokio::spawn(async move {
    let result = "Hello, World!".to_string();
    sender.send(result).unwrap();
});

let message = receiver.await.unwrap();
assert_eq!(message, "Hello, World!");

Performance Characteristics | 性能特点

lite

• Allocation: Zero heap allocation for values
• Size: Single AtomicU8 + AtomicWaker
• Latency: Minimal - direct atomic operations
• Best for: High-frequency notifications

generic

• Allocation: Zero heap allocation (value stored inline)
• Size: UnsafeCell<MaybeUninit<T>> + AtomicU8 + AtomicWaker
• Latency: Low - single atomic state transition
• Best for: Arbitrary data transfer

Thread Safety | 线程安全

Both implementations are fully thread-safe and lock-free:

• Sender can be called from any thread
• Receiver can be awaited from any task
• No spinlocks or blocking operations

两种实现都是完全线程安全且无锁的：

• Sender 可以从任何线程调用
• Receiver 可以从任何任务 await
• 无自旋锁或阻塞操作 Common types and traits shared between oneshot implementations.

一次性通道实现之间共享的公共类型和 trait。

Re-exports

pub use self::error::RecvError;

pub use self::error::TryRecvError;

Modules

error

Oneshot error types.

Structs

Inner

Inner state for oneshot channel

Receiver

Receiver for one-shot value transfer

Sender

Sender for one-shot value transfer

Enums

TakeResult

Result of trying to take a value from storage

Traits

OneshotStorage

Trait for oneshot value storage mechanisms

Functions

channel

Create a oneshot channel with the given storage type