Struct crossbeam_channel::flavors::array::Channel

pub(crate) struct Channel<T> {
    head: CachePadded<AtomicUsize>,
    tail: CachePadded<AtomicUsize>,
    buffer: Box<[Slot<T>]>,
    cap: usize,
    one_lap: usize,
    mark_bit: usize,
    senders: SyncWaker,
    receivers: SyncWaker,
}

Bounded channel based on a preallocated array.

Fields

head: CachePadded<AtomicUsize>

The head of the channel.

This value is a “stamp” consisting of an index into the buffer, a mark bit, and a lap, but packed into a single usize. The lower bits represent the index, while the upper bits represent the lap. The mark bit in the head is always zero.

Messages are popped from the head of the channel.

tail: CachePadded<AtomicUsize>

The tail of the channel.

This value is a “stamp” consisting of an index into the buffer, a mark bit, and a lap, but packed into a single usize. The lower bits represent the index, while the upper bits represent the lap. The mark bit indicates that the channel is disconnected.

Messages are pushed into the tail of the channel.

buffer: Box<[Slot<T>]>

The buffer holding slots.

cap: usize

The channel capacity.

one_lap: usize

A stamp with the value of { lap: 1, mark: 0, index: 0 }.

mark_bit: usize

If this bit is set in the tail, that means the channel is disconnected.

senders: SyncWaker

Senders waiting while the channel is full.

receivers: SyncWaker

Receivers waiting while the channel is empty and not disconnected.

Implementations

impl<T> Channel<T>

pub(crate) fn with_capacity(cap: usize) -> Self

Creates a bounded channel of capacity cap.

pub(crate) fn receiver(&self) -> Receiver<'_, T>

Returns a receiver handle to the channel.

pub(crate) fn sender(&self) -> Sender<'_, T>

Returns a sender handle to the channel.

fn start_send(&self, token: &mut Token) -> bool

Attempts to reserve a slot for sending a message.

pub(crate) unsafe fn write(&self, token: &mut Token, msg: T) -> Result<(), T>

Writes a message into the channel.

fn start_recv(&self, token: &mut Token) -> bool

Attempts to reserve a slot for receiving a message.

pub(crate) unsafe fn read(&self, token: &mut Token) -> Result<T, ()>

Reads a message from the channel.

pub(crate) fn try_send(&self, msg: T) -> Result<(), TrySendError<T>>

Attempts to send a message into the channel.

pub(crate) fn send( &self, msg: T, deadline: Option<Instant>, ) -> Result<(), SendTimeoutError<T>>

Sends a message into the channel.

pub(crate) fn try_recv(&self) -> Result<T, TryRecvError>

Attempts to receive a message without blocking.

pub(crate) fn recv( &self, deadline: Option<Instant>, ) -> Result<T, RecvTimeoutError>

Receives a message from the channel.

pub(crate) fn len(&self) -> usize

Returns the current number of messages inside the channel.

pub(crate) fn capacity(&self) -> Option<usize>

Returns the capacity of the channel.

pub(crate) fn disconnect(&self) -> bool

Disconnects the channel and wakes up all blocked senders and receivers.

Returns true if this call disconnected the channel.

pub(crate) fn is_disconnected(&self) -> bool

Returns true if the channel is disconnected.

pub(crate) fn is_empty(&self) -> bool

Returns true if the channel is empty.

pub(crate) fn is_full(&self) -> bool

Returns true if the channel is full.

Trait Implementations

impl<T> Drop for Channel<T>

fn drop(&mut self)

Executes the destructor for this type.