Trait trillium_server_common::AsyncWrite
pub trait AsyncWrite {
// Required methods
fn poll_write(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8]
) -> Poll<Result<usize, Error>>;
fn poll_flush(
self: Pin<&mut Self>,
cx: &mut Context<'_>
) -> Poll<Result<(), Error>>;
fn poll_close(
self: Pin<&mut Self>,
cx: &mut Context<'_>
) -> Poll<Result<(), Error>>;
// Provided method
fn poll_write_vectored(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
bufs: &[IoSlice<'_>]
) -> Poll<Result<usize, Error>> { ... }
}
Expand description
Write bytes asynchronously.
This trait is analogous to the std::io::Write
trait, but integrates
with the asynchronous task system. In particular, the poll_write
method, unlike Write::write
, will automatically queue the current task
for wakeup and return if the writer cannot take more data, rather than blocking
the calling thread.
Required Methods§
fn poll_write(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8]
) -> Poll<Result<usize, Error>>
fn poll_write( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &[u8] ) -> Poll<Result<usize, Error>>
Attempt to write bytes from buf
into the object.
On success, returns Poll::Ready(Ok(num_bytes_written))
.
If the object is not ready for writing, the method returns
Poll::Pending
and arranges for the current task (via
cx.waker().wake_by_ref()
) to receive a notification when the object becomes
writable or is closed.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Poll::Pending
and either internally retry or convert
Interrupted
into another error kind.
poll_write
must try to make progress by flushing the underlying object if
that is the only way the underlying object can become writable again.
fn poll_flush(
self: Pin<&mut Self>,
cx: &mut Context<'_>
) -> Poll<Result<(), Error>>
fn poll_flush( self: Pin<&mut Self>, cx: &mut Context<'_> ) -> Poll<Result<(), Error>>
Attempt to flush the object, ensuring that any buffered data reach their destination.
On success, returns Poll::Ready(Ok(()))
.
If flushing cannot immediately complete, this method returns
Poll::Pending
and arranges for the current task (via
cx.waker().wake_by_ref()
) to receive a notification when the object can make
progress towards flushing.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Poll::Pending
and either internally retry or convert
Interrupted
into another error kind.
It only makes sense to do anything here if you actually buffer data.
fn poll_close(
self: Pin<&mut Self>,
cx: &mut Context<'_>
) -> Poll<Result<(), Error>>
fn poll_close( self: Pin<&mut Self>, cx: &mut Context<'_> ) -> Poll<Result<(), Error>>
Attempt to close the object.
On success, returns Poll::Ready(Ok(()))
.
If closing cannot immediately complete, this function returns
Poll::Pending
and arranges for the current task (via
cx.waker().wake_by_ref()
) to receive a notification when the object can make
progress towards closing.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Poll::Pending
and either internally retry or convert
Interrupted
into another error kind.
Provided Methods§
fn poll_write_vectored(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
bufs: &[IoSlice<'_>]
) -> Poll<Result<usize, Error>>
fn poll_write_vectored( self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>] ) -> Poll<Result<usize, Error>>
Attempt to write bytes from bufs
into the object using vectored
IO operations.
This method is similar to poll_write
, but allows data from multiple buffers to be written
using a single operation.
On success, returns Poll::Ready(Ok(num_bytes_written))
.
If the object is not ready for writing, the method returns
Poll::Pending
and arranges for the current task (via
cx.waker().wake_by_ref()
) to receive a notification when the object becomes
writable or is closed.
By default, this method delegates to using poll_write
on the first
nonempty buffer in bufs
, or an empty one if none exists. Objects which
support vectored IO should override this method.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Poll::Pending
and either internally retry or convert
Interrupted
into another error kind.