wasmtime_wasi/p2/
ip_name_lookup.rs

1use crate::p2::SocketError;
2use crate::p2::bindings::sockets::ip_name_lookup::{Host, HostResolveAddressStream};
3use crate::p2::bindings::sockets::network::{ErrorCode, IpAddress, Network};
4use crate::sockets::ip_name_lookup::resolve_addresses;
5use crate::sockets::{MaybeReady, WasiSocketsCtxView, noop_cx};
6use std::net::IpAddr;
7use std::task::Poll;
8use std::vec;
9use wasmtime::Result;
10use wasmtime::component::Resource;
11use wasmtime_wasi_io::poll::{DynPollable, Pollable, subscribe};
12
13pub struct ResolveAddressStream(MaybeReady<Result<vec::IntoIter<IpAddr>, ErrorCode>>);
14
15impl Host for WasiSocketsCtxView<'_> {
16    fn resolve_addresses(
17        &mut self,
18        network: Resource<Network>,
19        name: String,
20    ) -> Result<Resource<ResolveAddressStream>, SocketError> {
21        // The network resource itself represents the capability to use this
22        // method, so we need to check its validity. Other than that, we have no
23        // use for it.
24        _ = self.table.get(&network)?;
25
26        let fut = resolve_addresses(&self.ctx, name);
27        let stream = ResolveAddressStream(MaybeReady::poll_or_spawn(async move {
28            Ok(fut.await?.into_iter())
29        }));
30
31        // Attempt to surface errors immediately.
32        if let MaybeReady::Ready(Err(err)) = &stream.0 {
33            return Err((*err).into());
34        }
35        Ok(self.table.push(stream)?)
36    }
37}
38
39impl HostResolveAddressStream for WasiSocketsCtxView<'_> {
40    fn resolve_next_address(
41        &mut self,
42        resource: Resource<ResolveAddressStream>,
43    ) -> Result<Option<IpAddress>, SocketError> {
44        let stream: &mut ResolveAddressStream = self.table.get_mut(&resource)?;
45        let Poll::Ready(result) = stream.0.poll_ready(&mut noop_cx()) else {
46            return Err(ErrorCode::WouldBlock.into());
47        };
48
49        match result {
50            Ok(iter) => Ok(iter.next().map(|addr| addr.into())),
51            Err(err) => Err((*err).into()),
52        }
53    }
54
55    fn subscribe(
56        &mut self,
57        resource: Resource<ResolveAddressStream>,
58    ) -> Result<Resource<DynPollable>> {
59        subscribe(self.table, resource)
60    }
61
62    fn drop(&mut self, resource: Resource<ResolveAddressStream>) -> Result<()> {
63        self.table.delete(resource)?;
64        Ok(())
65    }
66}
67
68#[async_trait::async_trait]
69impl Pollable for ResolveAddressStream {
70    async fn ready(&mut self) {
71        std::future::poll_fn(|cx| self.0.poll_ready(cx).map(|_| ())).await
72    }
73}
wasmtime_wasi/p2/ip_name_lookup.rs

wasmtime_wasi/p2/
ip_name_lookup.rs
