Struct zng_task::io::McBufReader

pub struct McBufReader<S: AsyncRead> { /* private fields */ }

Multiple consumer buffered read.

Clone an instance to create a new consumer, already read bytes stay in the buffer until all clones have read it, clones continue reading from the same offset as the reader they cloned.

A single instance of this reader behaves like a BufReader.

Result

The result is repeats ready when EOF or an Error occurs, unfortunately the IO error is not cloneable so the error is recreated using CloneableError for subsequent poll attempts.

The inner reader is dropped as soon as it finishes.

Lazy Clones

You can mark clones as lazy, lazy clones don’t pull from the inner reader, only advance when another clone reads, if all living clones are lazy they stop reading with an error. You can identify this custom error using the McBufErrorExt::is_only_lazy_left extension method.

Implementations

impl<S: AsyncRead> McBufReader<S>

pub fn new(source: S) -> Self

Creates a buffered reader.

pub fn is_lazy(&self) -> bool

Returns true if this reader does not pull from the inner reader, only advancing when a non-lazy reader advances.

The initial reader is not lazy, only clones of lazy readers are lazy by default.

pub fn set_lazy(&mut self, lazy: bool)

Sets is_lazy.

Trait Implementations

impl<S: AsyncRead> AsyncRead for McBufReader<S>

fn poll_read( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &mut [u8] ) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into buf.

fn poll_read_vectored( self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &mut [IoSliceMut<'_>] ) -> Poll<Result<usize, Error>>

Attempt to read from the AsyncRead into bufs using vectored IO operations.

impl<S: AsyncRead> Clone for McBufReader<S>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<S: AsyncRead> Drop for McBufReader<S>

fn drop(&mut self)

Executes the destructor for this type.