Interfaces
typessince 0.3.0ip-name-lookupsince 0.3.0
Worlds
imports
Exports
None
WIT
package wasi:sockets@0.3.0;
@since(version = 0.3.0)
interface types {
@since(version = 0.3.0)
use wasi:clocks/types@0.3.0.{duration};
/// Error codes.
///
/// In theory, every API can return any error code.
/// In practice, API's typically only return the errors documented per API
/// combined with a couple of errors that are always possible:
/// - `other`
/// - `access-denied`
/// - `not-supported`
/// - `out-of-memory`
///
/// See each individual API for what the POSIX equivalents are. They sometimes differ per API.
@since(version = 0.3.0)
variant error-code {
/// Access denied.
///
/// POSIX equivalent: EACCES, EPERM
access-denied,
/// The operation is not supported.
///
/// POSIX equivalent: EOPNOTSUPP, ENOPROTOOPT, EPFNOSUPPORT, EPROTONOSUPPORT, ESOCKTNOSUPPORT
not-supported,
/// One of the arguments is invalid.
///
/// POSIX equivalent: EINVAL, EDESTADDRREQ, EAFNOSUPPORT
invalid-argument,
/// Not enough memory to complete the operation.
///
/// POSIX equivalent: ENOMEM, ENOBUFS
out-of-memory,
/// The operation timed out before it could finish completely.
///
/// POSIX equivalent: ETIMEDOUT
timeout,
/// The operation is not valid in the socket's current state.
invalid-state,
/// The local address is not available.
///
/// POSIX equivalent: EADDRNOTAVAIL
address-not-bindable,
/// A bind operation failed because the provided address is already in
/// use or because there are no ephemeral ports available.
///
/// POSIX equivalent: EADDRINUSE
address-in-use,
/// The remote address is not reachable.
///
/// POSIX equivalent: EHOSTUNREACH, EHOSTDOWN, ENETDOWN, ENETUNREACH, ENONET
remote-unreachable,
/// The connection was forcefully rejected.
///
/// POSIX equivalent: ECONNREFUSED
connection-refused,
/// A write failed because the connection was broken.
///
/// POSIX equivalent: EPIPE
connection-broken,
/// The connection was reset.
///
/// POSIX equivalent: ECONNRESET
connection-reset,
/// The connection was aborted.
///
/// POSIX equivalent: ECONNABORTED
connection-aborted,
/// The size of a datagram sent to a UDP socket exceeded the maximum
/// supported size.
///
/// POSIX equivalent: EMSGSIZE
datagram-too-large,
/// A catch-all for errors not captured by the existing variants.
/// Implementations can use this to extend the error type without
/// breaking existing code.
other(option<string>),
}
@since(version = 0.3.0)
enum ip-address-family {
/// Similar to `AF_INET` in POSIX.
ipv4,
/// Similar to `AF_INET6` in POSIX.
ipv6,
}
@since(version = 0.3.0)
type ipv4-address = tuple<u8, u8, u8, u8>;
@since(version = 0.3.0)
type ipv6-address = tuple<u16, u16, u16, u16, u16, u16, u16, u16>;
@since(version = 0.3.0)
variant ip-address {
ipv4(ipv4-address),
ipv6(ipv6-address),
}
@since(version = 0.3.0)
record ipv4-socket-address {
/// sin_port
port: u16,
/// sin_addr
address: ipv4-address,
}
@since(version = 0.3.0)
record ipv6-socket-address {
/// sin6_port
port: u16,
/// sin6_flowinfo
flow-info: u32,
/// sin6_addr
address: ipv6-address,
/// sin6_scope_id
scope-id: u32,
}
@since(version = 0.3.0)
variant ip-socket-address {
ipv4(ipv4-socket-address),
ipv6(ipv6-socket-address),
}
/// A TCP socket resource.
///
/// The socket can be in one of the following states:
/// - `unbound`
/// - `bound` (See note below)
/// - `listening`
/// - `connecting`
/// - `connected`
/// - `closed`
/// See <https://github.com/WebAssembly/WASI/blob/main/proposals/sockets/TcpSocketOperationalSemantics-0.3.0.md>
/// for more information.
///
/// Note: Except where explicitly mentioned, whenever this documentation uses
/// the term "bound" without backticks it actually means: in the `bound` state *or higher*.
/// (i.e. `bound`, `listening`, `connecting` or `connected`)
///
/// WASI uses shared ownership semantics: the `tcp-socket` handle and all
/// derived `stream` and `future` values reference a single underlying OS
/// socket:
/// - Send/receive streams remain functional after the original `tcp-socket`
/// handle is dropped.
/// - The stream returned by `listen` behaves similarly.
/// - Client sockets returned by `tcp-socket::listen` are independent and do
/// not keep the listening socket alive.
///
/// The OS socket is closed only after the last handle is dropped. This
/// model has observable effects; for example, it affects when the local
/// port binding is released.
///
/// In addition to the general error codes documented on the
/// `types::error-code` type, TCP socket methods may always return
/// `error(invalid-state)` when in the `closed` state.
@since(version = 0.3.0)
resource tcp-socket {
/// Create a new TCP socket.
///
/// Similar to `socket(AF_INET or AF_INET6, SOCK_STREAM, IPPROTO_TCP)`
/// in POSIX. On IPv6 sockets, IPV6_V6ONLY is enabled by default and
/// can't be configured otherwise.
///
/// Unlike POSIX, WASI sockets have no notion of a socket-level
/// `O_NONBLOCK` flag. Instead they fully rely on the Component Model's
/// async support.
///
/// # Typical errors
/// - `not-supported`: The `address-family` is not supported. (EAFNOSUPPORT)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/socket.html>
/// - <https://man7.org/linux/man-pages/man2/socket.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsasocketw>
/// - <https://man.freebsd.org/cgi/man.cgi?query=socket&sektion=2>
@since(version = 0.3.0)
create: static func(address-family: ip-address-family) -> result<tcp-socket, error-code>;
/// Bind the socket to the provided IP address and port.
///
/// If the IP address is zero (`0.0.0.0` in IPv4, `::` in IPv6), it is
/// left to the implementation to decide which network interface(s) to
/// bind to. If the TCP/UDP port is zero, the socket will be bound to a
/// random free port.
///
/// Bind can be attempted multiple times on the same socket, even with
/// different arguments on each iteration. But never concurrently and
/// only as long as the previous bind failed. Once a bind succeeds, the
/// binding can't be changed anymore.
///
/// # Typical errors
/// - `invalid-argument`: The `local-address` has the wrong address family. (EAFNOSUPPORT, EFAULT on Windows)
/// - `invalid-argument`: `local-address` is not a unicast address. (EINVAL)
/// - `invalid-argument`: `local-address` is an IPv4-mapped IPv6 address. (EINVAL)
/// - `invalid-state`: The socket is already bound. (EINVAL)
/// - `address-in-use`: No ephemeral ports available. (EADDRINUSE, ENOBUFS on Windows)
/// - `address-in-use`: Address is already in use. (EADDRINUSE)
/// - `address-not-bindable`: `local-address` is not an address that can be bound to. (EADDRNOTAVAIL)
///
/// # Implementors note
/// The bind operation shouldn't be affected by the TIME_WAIT state of a
/// recently closed socket on the same local address. In practice this
/// means that the SO_REUSEADDR socket option should be set implicitly
/// on all platforms, except on Windows where this is the default
/// behavior and SO_REUSEADDR performs something different.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/bind.html>
/// - <https://man7.org/linux/man-pages/man2/bind.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-bind>
/// - <https://man.freebsd.org/cgi/man.cgi?query=bind&sektion=2&format=html>
@since(version = 0.3.0)
bind: func(local-address: ip-socket-address) -> result<_, error-code>;
/// Connect to a remote endpoint.
///
/// On success, the socket is transitioned into the `connected` state
/// and the `remote-address` of the socket is updated.
/// The `local-address` may be updated as well, based on the best network
/// path to `remote-address`. If the socket was not already explicitly
/// bound, this function will implicitly bind the socket to a random
/// free port.
///
/// After a failed connection attempt, the socket will be in the `closed`
/// state and the only valid action left is to `drop` the socket. A single
/// socket can not be used to connect more than once.
///
/// # Typical errors
/// - `invalid-argument`: The `remote-address` has the wrong address family. (EAFNOSUPPORT)
/// - `invalid-argument`: `remote-address` is not a unicast address. (EINVAL, ENETUNREACH on Linux, EAFNOSUPPORT on MacOS)
/// - `invalid-argument`: `remote-address` is an IPv4-mapped IPv6 address. (EINVAL, EADDRNOTAVAIL on Illumos)
/// - `invalid-argument`: The IP address in `remote-address` is set to INADDR_ANY (`0.0.0.0` / `::`). (EADDRNOTAVAIL on Windows)
/// - `invalid-argument`: The port in `remote-address` is set to 0. (EADDRNOTAVAIL on Windows)
/// - `invalid-state`: The socket is already in the `connecting` state. (EALREADY)
/// - `invalid-state`: The socket is already in the `connected` state. (EISCONN)
/// - `invalid-state`: The socket is already in the `listening` state. (EOPNOTSUPP, EINVAL on Windows)
/// - `timeout`: Connection timed out. (ETIMEDOUT)
/// - `connection-refused`: The connection was forcefully rejected. (ECONNREFUSED)
/// - `connection-reset`: The connection was reset. (ECONNRESET)
/// - `connection-aborted`: The connection was aborted. (ECONNABORTED)
/// - `remote-unreachable`: The remote address is not reachable. (EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
/// - `address-in-use`: Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE, EADDRNOTAVAIL on Linux, EAGAIN on BSD)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/connect.html>
/// - <https://man7.org/linux/man-pages/man2/connect.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-connect>
/// - <https://man.freebsd.org/cgi/man.cgi?connect>
@since(version = 0.3.0)
connect: async func(remote-address: ip-socket-address) -> result<_, error-code>;
/// Start listening and return a stream of new inbound connections.
///
/// Transitions the socket into the `listening` state. This can be called
/// at most once per socket.
///
/// If the socket is not already explicitly bound, this function will
/// implicitly bind the socket to a random free port.
///
/// Normally, the returned sockets are bound, in the `connected` state
/// and immediately ready for I/O. Though, depending on exact timing and
/// circumstances, a newly accepted connection may already be `closed`
/// by the time the server attempts to perform its first I/O on it. This
/// is true regardless of whether the WASI implementation uses
/// "synthesized" sockets or not (see Implementors Notes below).
///
/// The following properties are inherited from the listener socket:
/// - `address-family`
/// - `keep-alive-enabled`
/// - `keep-alive-idle-time`
/// - `keep-alive-interval`
/// - `keep-alive-count`
/// - `hop-limit`
/// - `receive-buffer-size`
/// - `send-buffer-size`
///
/// # Typical errors
/// - `invalid-state`: The socket is already in the `connected` state. (EISCONN, EINVAL on BSD)
/// - `invalid-state`: The socket is already in the `listening` state.
/// - `address-in-use`: Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE)
///
/// # Implementors note
/// This method returns a single perpetual stream that should only close
/// on fatal errors (if any). Yet, the POSIX' `accept` function may also
/// return transient errors (e.g. ECONNABORTED). The exact details differ
/// per operation system. For example, the Linux manual mentions:
///
/// > Linux accept() passes already-pending network errors on the new
/// > socket as an error code from accept(). This behavior differs from
/// > other BSD socket implementations. For reliable operation the
/// > application should detect the network errors defined for the
/// > protocol after accept() and treat them like EAGAIN by retrying.
/// > In the case of TCP/IP, these are ENETDOWN, EPROTO, ENOPROTOOPT,
/// > EHOSTDOWN, ENONET, EHOSTUNREACH, EOPNOTSUPP, and ENETUNREACH.
/// Source: https://man7.org/linux/man-pages/man2/accept.2.html
///
/// WASI implementations have two options to handle this:
/// - Optionally log it and then skip over non-fatal errors returned by
/// `accept`. Guest code never gets to see these failures. Or:
/// - Synthesize a `tcp-socket` resource that exposes the error when
/// attempting to send or receive on it. Guest code then sees these
/// failures as regular I/O errors.
///
/// In either case, the stream returned by this `listen` method remains
/// operational.
///
/// WASI requires `listen` to perform an implicit bind if the socket
/// has not already been bound. Not all platforms (notably Windows)
/// exhibit this behavior out of the box. On platforms that require it,
/// the WASI implementation can emulate this behavior by performing
/// the bind itself if the guest hasn't already done so.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/listen.html>
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/accept.html>
/// - <https://man7.org/linux/man-pages/man2/listen.2.html>
/// - <https://man7.org/linux/man-pages/man2/accept.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-listen>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-accept>
/// - <https://man.freebsd.org/cgi/man.cgi?query=listen&sektion=2>
/// - <https://man.freebsd.org/cgi/man.cgi?query=accept&sektion=2>
@since(version = 0.3.0)
listen: func() -> result<stream<tcp-socket>, error-code>;
/// Transmit data to peer.
///
/// The caller should close the stream when it has no more data to send
/// to the peer. Under normal circumstances this will cause a FIN packet
/// to be sent out. Closing the stream is equivalent to calling
/// `shutdown(SHUT_WR)` in POSIX.
///
/// This function may be called at most once and returns once the full
/// contents of the stream are transmitted or an error is encountered.
///
/// # Typical errors
/// - `invalid-state`: The socket is not in the `connected` state. (ENOTCONN)
/// - `invalid-state`: `send` has already been called on this socket.
/// - `connection-broken`: The connection is not writable anymore. (EPIPE, ECONNABORTED on Windows)
/// - `connection-reset`: The connection was reset. (ECONNRESET)
/// - `remote-unreachable`: The remote address is not reachable. (EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/send.html>
/// - <https://man7.org/linux/man-pages/man2/send.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-send>
/// - <https://man.freebsd.org/cgi/man.cgi?query=send&sektion=2>
@since(version = 0.3.0)
send: func(data: stream<u8>) -> future<result<_, error-code>>;
/// Read data from peer.
///
/// Returns a `stream` of data sent by the peer. The implementation
/// drops the stream once no more data is available. At that point, the
/// returned `future` resolves to:
/// - `ok` after a graceful shutdown from the peer (i.e. a FIN packet), or
/// - `err` if the socket was closed abnormally.
///
/// `receive` may be called only once per socket. Subsequent calls return
/// a closed stream and a future resolved to `err(invalid-state)`.
///
/// If the caller is not expecting to receive any more data from the peer,
/// they should drop the stream. Any data still in the receive queue
/// will be discarded. This is equivalent to calling `shutdown(SHUT_RD)`
/// in POSIX.
///
/// # Typical errors
/// - `invalid-state`: The socket is not in the `connected` state. (ENOTCONN)
/// - `invalid-state`: `receive` has already been called on this socket.
/// - `connection-reset`: The connection was reset. (ECONNRESET)
/// - `remote-unreachable`: The remote address is not reachable. (EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/recv.html>
/// - <https://man7.org/linux/man-pages/man2/recv.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-recv>
/// - <https://man.freebsd.org/cgi/man.cgi?query=recv&sektion=2>
@since(version = 0.3.0)
receive: func() -> tuple<stream<u8>, future<result<_, error-code>>>;
/// Get the bound local address.
///
/// POSIX mentions:
/// > If the socket has not been bound to a local name, the value
/// > stored in the object pointed to by `address` is unspecified.
///
/// WASI is stricter and requires `get-local-address` to return
/// `invalid-state` when the socket hasn't been bound yet.
///
/// # Typical errors
/// - `invalid-state`: The socket is not bound to any local address.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/getsockname.html>
/// - <https://man7.org/linux/man-pages/man2/getsockname.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-getsockname>
/// - <https://man.freebsd.org/cgi/man.cgi?getsockname>
@since(version = 0.3.0)
get-local-address: func() -> result<ip-socket-address, error-code>;
/// Get the remote address.
///
/// # Typical errors
/// - `invalid-state`: The socket is not connected to a remote address. (ENOTCONN)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/getpeername.html>
/// - <https://man7.org/linux/man-pages/man2/getpeername.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-getpeername>
/// - <https://man.freebsd.org/cgi/man.cgi?query=getpeername&sektion=2&n=1>
@since(version = 0.3.0)
get-remote-address: func() -> result<ip-socket-address, error-code>;
/// Whether the socket is in the `listening` state.
///
/// Equivalent to the SO_ACCEPTCONN socket option.
@since(version = 0.3.0)
get-is-listening: func() -> bool;
/// Whether this is a IPv4 or IPv6 socket.
///
/// This is the value passed to the constructor.
///
/// Equivalent to the SO_DOMAIN socket option.
@since(version = 0.3.0)
get-address-family: func() -> ip-address-family;
/// Hints the desired listen queue size. Implementations are free to
/// ignore this.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
/// Any other value will never cause an error, but it might be silently
/// clamped and/or rounded.
///
/// # Typical errors
/// - `not-supported`: (set) The platform does not support changing the backlog size after the initial listen.
/// - `invalid-argument`: (set) The provided value was 0.
/// - `invalid-state`: (set) The socket is in the `connecting` or `connected` state.
@since(version = 0.3.0)
set-listen-backlog-size: func(value: u64) -> result<_, error-code>;
/// Enables or disables keepalive.
///
/// The keepalive behavior can be adjusted using:
/// - `keep-alive-idle-time`
/// - `keep-alive-interval`
/// - `keep-alive-count`
/// These properties can be configured while `keep-alive-enabled` is
/// false, but only come into effect when `keep-alive-enabled` is true.
///
/// Equivalent to the SO_KEEPALIVE socket option.
@since(version = 0.3.0)
get-keep-alive-enabled: func() -> result<bool, error-code>;
@since(version = 0.3.0)
set-keep-alive-enabled: func(value: bool) -> result<_, error-code>;
/// Amount of time the connection has to be idle before TCP starts
/// sending keepalive packets.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
/// All other values are accepted without error, but may be
/// clamped or rounded. As a result, the value read back from
/// this setting may differ from the value that was set.
///
/// Equivalent to the TCP_KEEPIDLE socket option. (TCP_KEEPALIVE on MacOS)
///
/// # Typical errors
/// - `invalid-argument`: (set) The provided value was 0.
@since(version = 0.3.0)
get-keep-alive-idle-time: func() -> result<duration, error-code>;
@since(version = 0.3.0)
set-keep-alive-idle-time: func(value: duration) -> result<_, error-code>;
/// The time between keepalive packets.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
/// All other values are accepted without error, but may be
/// clamped or rounded. As a result, the value read back from
/// this setting may differ from the value that was set.
///
/// Equivalent to the TCP_KEEPINTVL socket option.
///
/// # Typical errors
/// - `invalid-argument`: (set) The provided value was 0.
@since(version = 0.3.0)
get-keep-alive-interval: func() -> result<duration, error-code>;
@since(version = 0.3.0)
set-keep-alive-interval: func(value: duration) -> result<_, error-code>;
/// The maximum amount of keepalive packets TCP should send before
/// aborting the connection.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
/// All other values are accepted without error, but may be
/// clamped or rounded. As a result, the value read back from
/// this setting may differ from the value that was set.
///
/// Equivalent to the TCP_KEEPCNT socket option.
///
/// # Typical errors
/// - `invalid-argument`: (set) The provided value was 0.
@since(version = 0.3.0)
get-keep-alive-count: func() -> result<u32, error-code>;
@since(version = 0.3.0)
set-keep-alive-count: func(value: u32) -> result<_, error-code>;
/// Equivalent to the IP_TTL & IPV6_UNICAST_HOPS socket options.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
///
/// # Typical errors
/// - `invalid-argument`: (set) The TTL value must be 1 or higher.
@since(version = 0.3.0)
get-hop-limit: func() -> result<u8, error-code>;
@since(version = 0.3.0)
set-hop-limit: func(value: u8) -> result<_, error-code>;
/// Kernel buffer space reserved for sending/receiving on this socket.
/// Implementations usually treat this as a cap the buffer can grow to,
/// rather than allocating the full amount immediately.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
/// All other values are accepted without error, but may be
/// clamped or rounded. As a result, the value read back from
/// this setting may differ from the value that was set.
///
/// This is only a performance hint. The implementation may ignore it or
/// tweak it based on real traffic patterns.
/// Linux and macOS appear to behave differently depending on whether a
/// buffer size was explicitly set. When set, they tend to honor it; when
/// not set, they dynamically adjust the buffer size as the connection
/// progresses. This is especially noticeable when comparing the values
/// from before and after connection establishment.
///
/// Equivalent to the SO_RCVBUF and SO_SNDBUF socket options.
///
/// # Typical errors
/// - `invalid-argument`: (set) The provided value was 0.
@since(version = 0.3.0)
get-receive-buffer-size: func() -> result<u64, error-code>;
@since(version = 0.3.0)
set-receive-buffer-size: func(value: u64) -> result<_, error-code>;
@since(version = 0.3.0)
get-send-buffer-size: func() -> result<u64, error-code>;
@since(version = 0.3.0)
set-send-buffer-size: func(value: u64) -> result<_, error-code>;
}
/// A UDP socket handle.
@since(version = 0.3.0)
resource udp-socket {
/// Create a new UDP socket.
///
/// Similar to `socket(AF_INET or AF_INET6, SOCK_DGRAM, IPPROTO_UDP)`
/// in POSIX. On IPv6 sockets, IPV6_V6ONLY is enabled by default and
/// can't be configured otherwise.
///
/// Unlike POSIX, WASI sockets have no notion of a socket-level
/// `O_NONBLOCK` flag. Instead they fully rely on the Component Model's
/// async support.
///
/// # References:
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/socket.html>
/// - <https://man7.org/linux/man-pages/man2/socket.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsasocketw>
/// - <https://man.freebsd.org/cgi/man.cgi?query=socket&sektion=2>
@since(version = 0.3.0)
create: static func(address-family: ip-address-family) -> result<udp-socket, error-code>;
/// Bind the socket to the provided IP address and port.
///
/// If the IP address is zero (`0.0.0.0` in IPv4, `::` in IPv6), it is
/// left to the implementation to decide which network interface(s) to
/// bind to. If the port is zero, the socket will be bound to a random
/// free port.
///
/// # Typical errors
/// - `invalid-argument`: The `local-address` has the wrong address family. (EAFNOSUPPORT, EFAULT on Windows)
/// - `invalid-state`: The socket is already bound. (EINVAL)
/// - `address-in-use`: No ephemeral ports available. (EADDRINUSE, ENOBUFS on Windows)
/// - `address-in-use`: Address is already in use. (EADDRINUSE)
/// - `address-not-bindable`: `local-address` is not an address that can be bound to. (EADDRNOTAVAIL)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/bind.html>
/// - <https://man7.org/linux/man-pages/man2/bind.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-bind>
/// - <https://man.freebsd.org/cgi/man.cgi?query=bind&sektion=2&format=html>
@since(version = 0.3.0)
bind: func(local-address: ip-socket-address) -> result<_, error-code>;
/// Associate this socket with a specific peer address.
///
/// On success, the `remote-address` of the socket is updated.
/// The `local-address` may be updated as well, based on the best network
/// path to `remote-address`. If the socket was not already explicitly
/// bound, this function will implicitly bind the socket to a random
/// free port.
///
/// When a UDP socket is "connected", the `send` and `receive` methods
/// are limited to communicating with that peer only:
/// - `send` can only be used to send to this destination.
/// - `receive` will only return datagrams sent from the provided `remote-address`.
///
/// The name "connect" was kept to align with the existing POSIX
/// terminology. Other than that, this function only changes the local
/// socket configuration and does not generate any network traffic.
/// The peer is not aware of this "connection".
///
/// This method may be called multiple times on the same socket to change
/// its association, but only the most recent one will be effective.
///
/// # Typical errors
/// - `invalid-argument`: The `remote-address` has the wrong address family. (EAFNOSUPPORT)
/// - `invalid-argument`: The IP address in `remote-address` is set to INADDR_ANY (`0.0.0.0` / `::`). (EDESTADDRREQ, EADDRNOTAVAIL)
/// - `invalid-argument`: The port in `remote-address` is set to 0. (EDESTADDRREQ, EADDRNOTAVAIL)
/// - `address-in-use`: Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE, EADDRNOTAVAIL on Linux, EAGAIN on BSD)
///
/// # Implementors note
/// If the socket is already connected, some platforms (e.g. Linux)
/// require a disconnect before connecting to a different peer address.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/connect.html>
/// - <https://man7.org/linux/man-pages/man2/connect.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-connect>
/// - <https://man.freebsd.org/cgi/man.cgi?connect>
@since(version = 0.3.0)
connect: func(remote-address: ip-socket-address) -> result<_, error-code>;
/// Dissociate this socket from its peer address.
///
/// After calling this method, `send` & `receive` are free to communicate
/// with any remote address again.
///
/// The POSIX equivalent of this is calling `connect` with an `AF_UNSPEC` address.
///
/// # Typical errors
/// - `invalid-state`: The socket is not connected.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/connect.html>
/// - <https://man7.org/linux/man-pages/man2/connect.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-connect>
/// - <https://man.freebsd.org/cgi/man.cgi?connect>
@since(version = 0.3.0)
disconnect: func() -> result<_, error-code>;
/// Send a message on the socket to a particular peer.
///
/// If the socket is connected, the peer address may be left empty. In
/// that case this is equivalent to `send` in POSIX. Otherwise it is
/// equivalent to `sendto`.
///
/// Additionally, if the socket is connected, a `remote-address` argument
/// _may_ be provided but then it must be identical to the address
/// passed to `connect`.
///
/// If the socket has not been explicitly bound, it will be
/// implicitly bound to a random free port.
///
/// Implementations may trap if the `data` length exceeds 64 KiB.
///
/// # Typical errors
/// - `invalid-argument`: The `remote-address` has the wrong address family. (EAFNOSUPPORT)
/// - `invalid-argument`: The IP address in `remote-address` is set to INADDR_ANY (`0.0.0.0` / `::`). (EDESTADDRREQ, EADDRNOTAVAIL)
/// - `invalid-argument`: The port in `remote-address` is set to 0. (EDESTADDRREQ, EADDRNOTAVAIL)
/// - `invalid-argument`: The socket is in "connected" mode and `remote-address` is `some` value that does not match the address passed to `connect`. (EISCONN)
/// - `invalid-argument`: The socket is not "connected" and no value for `remote-address` was provided. (EDESTADDRREQ)
/// - `remote-unreachable`: The remote address is not reachable. (ECONNRESET, ENETRESET on Windows, EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
/// - `connection-refused`: The connection was refused. (ECONNREFUSED)
/// - `datagram-too-large`: The datagram is too large. (EMSGSIZE)
/// - `address-in-use`: Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE)
///
/// # Implementors note
/// WASI requires `send` to perform an implicit bind if the socket
/// has not been bound. Not all platforms (notably Windows) exhibit
/// this behavior natively. On such platforms, the WASI implementation
/// should emulate it by performing the bind if the guest has not
/// already done so.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/sendto.html>
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/sendmsg.html>
/// - <https://man7.org/linux/man-pages/man2/send.2.html>
/// - <https://man7.org/linux/man-pages/man2/sendmmsg.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-send>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-sendto>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsasendmsg>
/// - <https://man.freebsd.org/cgi/man.cgi?query=send&sektion=2>
@since(version = 0.3.0)
send: async func(data: list<u8>, remote-address: option<ip-socket-address>) -> result<_, error-code>;
/// Receive a message on the socket.
///
/// On success, the return value contains a tuple of the received data
/// and the address of the sender. Theoretical maximum length of the
/// data is 64 KiB. Though in practice, it will typically be less than
/// 1500 bytes.
///
/// If the socket is connected, the sender address is guaranteed to
/// match the remote address passed to `connect`.
///
/// # Typical errors
/// - `invalid-state`: The socket has not been bound yet.
/// - `remote-unreachable`: The remote address is not reachable. (ECONNRESET, ENETRESET on Windows, EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
/// - `connection-refused`: The connection was refused. (ECONNREFUSED)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/recvfrom.html>
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/recvmsg.html>
/// - <https://man7.org/linux/man-pages/man2/recv.2.html>
/// - <https://man7.org/linux/man-pages/man2/recvmmsg.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-recvfrom>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/mswsock/nc-mswsock-lpfn_wsarecvmsg>
/// - <https://man.freebsd.org/cgi/man.cgi?query=recv&sektion=2>
@since(version = 0.3.0)
receive: async func() -> result<tuple<list<u8>, ip-socket-address>, error-code>;
/// Get the current bound address.
///
/// POSIX mentions:
/// > If the socket has not been bound to a local name, the value
/// > stored in the object pointed to by `address` is unspecified.
///
/// WASI is stricter and requires `get-local-address` to return
/// `invalid-state` when the socket hasn't been bound yet.
///
/// # Typical errors
/// - `invalid-state`: The socket is not bound to any local address.
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/getsockname.html>
/// - <https://man7.org/linux/man-pages/man2/getsockname.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-getsockname>
/// - <https://man.freebsd.org/cgi/man.cgi?getsockname>
@since(version = 0.3.0)
get-local-address: func() -> result<ip-socket-address, error-code>;
/// Get the address the socket is currently "connected" to.
///
/// # Typical errors
/// - `invalid-state`: The socket is not "connected" to a specific remote address. (ENOTCONN)
///
/// # References
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/getpeername.html>
/// - <https://man7.org/linux/man-pages/man2/getpeername.2.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-getpeername>
/// - <https://man.freebsd.org/cgi/man.cgi?query=getpeername&sektion=2&n=1>
@since(version = 0.3.0)
get-remote-address: func() -> result<ip-socket-address, error-code>;
/// Whether this is a IPv4 or IPv6 socket.
///
/// This is the value passed to the constructor.
///
/// Equivalent to the SO_DOMAIN socket option.
@since(version = 0.3.0)
get-address-family: func() -> ip-address-family;
/// Equivalent to the IP_TTL & IPV6_UNICAST_HOPS socket options.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
///
/// # Typical errors
/// - `invalid-argument`: (set) The TTL value must be 1 or higher.
@since(version = 0.3.0)
get-unicast-hop-limit: func() -> result<u8, error-code>;
@since(version = 0.3.0)
set-unicast-hop-limit: func(value: u8) -> result<_, error-code>;
/// Kernel buffer space reserved for sending/receiving on this socket.
/// Implementations usually treat this as a cap the buffer can grow to,
/// rather than allocating the full amount immediately.
///
/// If the provided value is 0, an `invalid-argument` error is returned.
/// All other values are accepted without error, but may be
/// clamped or rounded. As a result, the value read back from
/// this setting may differ from the value that was set.
///
/// Equivalent to the SO_RCVBUF and SO_SNDBUF socket options.
///
/// # Typical errors
/// - `invalid-argument`: (set) The provided value was 0.
@since(version = 0.3.0)
get-receive-buffer-size: func() -> result<u64, error-code>;
@since(version = 0.3.0)
set-receive-buffer-size: func(value: u64) -> result<_, error-code>;
@since(version = 0.3.0)
get-send-buffer-size: func() -> result<u64, error-code>;
@since(version = 0.3.0)
set-send-buffer-size: func(value: u64) -> result<_, error-code>;
}
}
@since(version = 0.3.0)
interface ip-name-lookup {
@since(version = 0.3.0)
use types.{ip-address};
/// Lookup error codes.
@since(version = 0.3.0)
variant error-code {
/// Access denied.
///
/// POSIX equivalent: EACCES, EPERM
access-denied,
/// `name` is a syntactically invalid domain name or IP address.
///
/// POSIX equivalent: EINVAL
invalid-argument,
/// Name does not exist or has no suitable associated IP addresses.
///
/// POSIX equivalent: EAI_NONAME, EAI_NODATA, EAI_ADDRFAMILY
name-unresolvable,
/// A temporary failure in name resolution occurred.
///
/// POSIX equivalent: EAI_AGAIN
temporary-resolver-failure,
/// A permanent failure in name resolution occurred.
///
/// POSIX equivalent: EAI_FAIL
permanent-resolver-failure,
/// A catch-all for errors not captured by the existing variants.
/// Implementations can use this to extend the error type without
/// breaking existing code.
other(option<string>),
}
/// Resolve an internet host name to a list of IP addresses.
///
/// Unicode domain names are automatically converted to ASCII using IDNA
/// encoding. If the input is an IP address string, the address is parsed
/// and returned as-is without making any external requests.
///
/// See the wasi-socket proposal README.md for a comparison with getaddrinfo.
///
/// The results are returned in connection order preference.
///
/// This function never succeeds with 0 results. It either fails or succeeds
/// with at least one address. Additionally, this function never returns
/// IPv4-mapped IPv6 addresses.
///
/// # References:
/// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html>
/// - <https://man7.org/linux/man-pages/man3/getaddrinfo.3.html>
/// - <https://learn.microsoft.com/en-us/windows/win32/api/ws2tcpip/nf-ws2tcpip-getaddrinfo>
/// - <https://man.freebsd.org/cgi/man.cgi?query=getaddrinfo&sektion=3>
@since(version = 0.3.0)
resolve-addresses: async func(name: string) -> result<list<ip-address>, error-code>;
}
@since(version = 0.3.0)
world imports {
@since(version = 0.3.0)
import wasi:clocks/types@0.3.0;
@since(version = 0.3.0)
import types;
@since(version = 0.3.0)
import ip-name-lookup;
}