WASI Preview2

wasi-default-network.wit

@@ -0,0 +1,9 @@
+
+/// This interface provides a value-export of the default network handle..
+default interface wasi-default-network {
+	use pkg.wasi-network.{network}
+
+	/// Get a handle to the default network.
+	default-network: func() -> network
+
+}

wasi-ip-name-lookup.wit

@@ -1,32 +1,71 @@
-use { error, ip-address, ip-address-family } from common-types
-use { network } from wasi-network
-
-/// Resolve an internet host name to a list of IP addresses.
-/// 
-/// See the proposal README.md for a comparison with getaddrinfo.
-/// 
-/// Parameters:
-/// - `name`: The name to look up. IP addresses are not allowed. Unicode domain names are automatically converted
-///     to ASCII using IDNA encoding.
-/// - `address-family`: If provided, limit the results to addresses of this specific address family.
-/// - `include-unavailable`: When set to true, this function will also return addresses of which the runtime
-///   thinks (or knows) can't be connected to at the moment. For example, this will return IPv6 addresses on
-///   systems without an active IPv6 interface. Notes:
-///     - Even when no public IPv6 interfaces are present or active, names like "localhost" can still resolve to an IPv6 address.
-///     - Whatever is "available" or "unavailable" is volatile and can change everytime a network cable is unplugged.
-/// 
-/// Results:
-/// - When successful, there is always at least one result.
-/// - The results are returned in the order the runtime thinks the application should try to connect to first.
-/// - Never returns IPv4-mapped IPv6 addresses.
-/// 
-/// Returns EAI_FAIL when `name` is:
-/// - empty
-/// - an IP address
-/// - a syntactically invalid domain name in another way
-/// 
-/// References:
-/// - https://pubs.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html
-/// - https://man7.org/linux/man-pages/man3/getaddrinfo.3.html
-/// 
-resolve-addresses: func(name: string, address-family: option<ip-address-family>, include-unavailable: bool) -> future<expected<list<ip-address>, error>>
+
+default interface wasi-ip-name-lookup {
+	use pkg.wasi-poll.{pollable}
+	use pkg.wasi-network.{network, error, ip-address, ip-address-family}
+
+
+	/// Resolve an internet host name to a list of IP addresses.
+	/// 
+	/// See the wasi-socket proposal README.md for a comparison with getaddrinfo.
+	/// 
+	/// Parameters:
+	/// - `name`: The name to look up. IP addresses are not allowed. Unicode domain names are automatically converted
+	///     to ASCII using IDNA encoding.
+	/// - `address-family`: If provided, limit the results to addresses of this specific address family.
+	/// - `include-unavailable`: When set to true, this function will also return addresses of which the runtime
+	///   thinks (or knows) can't be connected to at the moment. For example, this will return IPv6 addresses on
+	///   systems without an active IPv6 interface. Notes:
+	///     - Even when no public IPv6 interfaces are present or active, names like "localhost" can still resolve to an IPv6 address.
+	///     - Whatever is "available" or "unavailable" is volatile and can change everytime a network cable is unplugged.
+	/// 
+	/// This function never blocks. It either immediately returns successfully with a `resolve-address-stream`
+	/// that can be used to (asynchronously) fetch the results.
+	/// Or it immediately fails whenever `name` is:
+	/// - empty
+	/// - an IP address
+	/// - a syntactically invalid domain name in another way
+	/// 
+	/// References:
+	/// - https://pubs.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html
+	/// - https://man7.org/linux/man-pages/man3/getaddrinfo.3.html
+	/// 
+	resolve-addresses: func(network: network, name: string, address-family: option<ip-address-family>, include-unavailable: bool) -> result<resolve-address-stream, error>
+
+
+
+    type resolve-address-stream = u32
+
+	/// Returns the next address from the resolver.
+	/// 
+	/// This function should be called multiple times. On each call, it will
+	/// return the next address in connection order preference. If all
+	/// addresses have been exhausted, this function returns `none`.
+	/// After which, you should release the stream with `drop-resolve-address-stream`.
+	/// 
+	/// This function never returns IPv4-mapped IPv6 addresses.
+	resolve-next-address: func(this: resolve-address-stream) -> result<option<ip-address>, error>
+
+
+
+	/// Dispose of the specified `resolve-address-stream`, after which it may no longer be used.
+	/// 
+	/// Note: this function is scheduled to be removed when Resources are natively supported in Wit.
+	drop-resolve-address-stream: func(this: resolve-address-stream)
+
+	/// Get/set the blocking mode of the stream.
+	/// 
+	/// By default a stream is in "blocking" mode, meaning that any function blocks and waits for its completion.
+	/// When switched to "non-blocking" mode, operations that would block return an `again` error. After which
+	/// the API consumer is expected to call `subscribe` and wait for completion using the wasi-poll module.
+	/// 
+	/// Note: these functions are here for WASI Preview2 only.
+	/// They're planned to be removed when `future` is natively supported in Preview3.
+	non-blocking: func(this: resolve-address-stream) -> result<bool, error>
+	set-non-blocking: func(this: resolve-address-stream, value: bool) -> result<_, error>
+
+	/// Create a `pollable` which will resolve once the stream is ready for I/O.
+	/// 
+	/// Note: this function is here for WASI Preview2 only.
+	/// It's planned to be removed when `future` is natively supported in Preview3.
+	subscribe: func(this: resolve-address-stream) -> pollable
+}

wasi-network.wit

@@ -1,3 +1,56 @@
 
-/// Capability handle for accessing network-related functions.
-resource network {}
+default interface wasi-network {
+    /// An opaque resource that represents access to (a subset of) the network.
+	/// This enables context-based security for networking.
+	/// There is no need for this to map 1:1 to a physical network interface.
+	/// 
+	/// FYI, In the future this will be replaced by handle types.
+    type network = u32
+
+	/// Dispose of the specified `network`, after which it may no longer be used.
+	/// 
+	/// Note: this function is scheduled to be removed when Resources are natively supported in Wit.
+	drop-network: func(this: network)
+
+
+
+	enum error {
+		unknown,
+		again,
+		// TODO ...
+	}
+
+	enum ip-address-family {
+		/// Similar to `AF_INET` in POSIX.
+		ipv4, 
+
+		/// Similar to `AF_INET6` in POSIX.
+		ipv6,
+	}
+
+	type ipv4-address = tuple<u8, u8, u8, u8>
+	type ipv6-address = tuple<u16, u16, u16, u16, u16, u16, u16, u16>
+
+	variant ip-address {
+		ipv4(ipv4-address),
+		ipv6(ipv6-address),
+	}
+
+	record ipv4-socket-address {
+		port: u16, // sin_port
+		address: ipv4-address, // sin_addr
+	}
+
+	record ipv6-socket-address {
+		port: u16, // sin6_port
+		flow-info: u32, // sin6_flowinfo
+		address: ipv6-address, // sin6_addr
+		scope-id: u32, // sin6_scope_id
+	}
+
+	variant ip-socket-address {
+		ipv4(ipv4-socket-address),
+		ipv6(ipv6-socket-address),
+	}
+
+}