| use std::{ |
| io, |
| pin::Pin, |
| task::{Context, Poll}, |
| }; |
| |
| pub(crate) trait AsyncBufWrite { |
| /// Attempt to return an internal buffer to write to, flushing data out to the inner reader if |
| /// it is full. |
| /// |
| /// On success, returns `Poll::Ready(Ok(buf))`. |
| /// |
| /// If the buffer is full and cannot be flushed, the method returns `Poll::Pending` and |
| /// arranges for the current task context (`cx`) to receive a notification when the object |
| /// becomes readable or is closed. |
| fn poll_partial_flush_buf( |
| self: Pin<&mut Self>, |
| cx: &mut Context<'_>, |
| ) -> Poll<io::Result<&mut [u8]>>; |
| |
| /// Tells this buffer that `amt` bytes have been written to its buffer, so they should be |
| /// written out to the underlying IO when possible. |
| /// |
| /// This function is a lower-level call. It needs to be paired with the `poll_flush_buf` method to |
| /// function properly. This function does not perform any I/O, it simply informs this object |
| /// that some amount of its buffer, returned from `poll_flush_buf`, has been written to and should |
| /// be sent. As such, this function may do odd things if `poll_flush_buf` isn't |
| /// called before calling it. |
| /// |
| /// The `amt` must be `<=` the number of bytes in the buffer returned by `poll_flush_buf`. |
| fn produce(self: Pin<&mut Self>, amt: usize); |
| } |
