async_ringbuf/
transfer.rs

1use crate::{consumer::AsyncConsumer, producer::AsyncProducer};
2
3/// Tranfer data from one ring buffer to another.
4///
5/// `count` is the number of items to transfer.
6/// The number of actually transfered items is returned.
7///
8/// If `count` is `Some(n)` then exactly `n` items will be transfered on completion
9/// except the situation when `src` or `dst` is closed or the future is dropped before completion.
10///
11/// If `count` is `None` then transfer will be performed until the one or another ring buffer is closed.
12///
13/// # Cancel safety
14///
15/// Transfer safely stops if the future is dropped.
16pub async fn async_transfer<T, As: AsyncConsumer<Item = T>, Ad: AsyncProducer<Item = T>>(
17    src: &mut As,
18    dst: &mut Ad,
19    count: Option<usize>,
20) -> usize {
21    let mut actual_count = 0;
22    // TODO: Transfer multiple items at once.
23    loop {
24        if count.as_ref().is_some_and(|n| actual_count == *n) {
25            break;
26        }
27        actual_count += 1;
28
29        match dst
30            .push(match src.pop().await {
31                Some(item) => item,
32                None => break,
33            })
34            .await
35        {
36            Ok(()) => (),
37            Err(_item) => break,
38        };
39    }
40    actual_count
41}
async_ringbuf/transfer.rs

async_ringbuf/
transfer.rs
