package wasi:sockets@0.2.10;

@since(version = 0.2.0)
interface network {
  @unstable(feature = network-error-code)
  use wasi:io/error@0.2.10.{error};

  /// 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.
  @since(version = 0.2.0)
  resource network;

  /// 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:
  /// - `unknown`
  /// - `access-denied`
  /// - `not-supported`
  /// - `out-of-memory`
  /// - `concurrency-conflict`
  ///
  /// See each individual API for what the POSIX equivalents are. They sometimes differ per API.
  @since(version = 0.2.0)
  enum error-code {
    /// Unknown error
    unknown,
    /// Access denied.
    ///
    /// POSIX equivalent: EACCES, EPERM
    access-denied,
    /// The operation is not supported.
    ///
    /// POSIX equivalent: EOPNOTSUPP
    not-supported,
    /// One of the arguments is invalid.
    ///
    /// POSIX equivalent: EINVAL
    invalid-argument,
    /// Not enough memory to complete the operation.
    ///
    /// POSIX equivalent: ENOMEM, ENOBUFS, EAI_MEMORY
    out-of-memory,
    /// The operation timed out before it could finish completely.
    timeout,
    /// This operation is incompatible with another asynchronous operation that is already in progress.
    ///
    /// POSIX equivalent: EALREADY
    concurrency-conflict,
    /// Trying to finish an asynchronous operation that:
    /// - has not been started yet, or:
    /// - was already finished by a previous `finish-*` call.
    ///
    /// Note: this is scheduled to be removed when `future`s are natively supported.
    not-in-progress,
    /// The operation has been aborted because it could not be completed immediately.
    ///
    /// Note: this is scheduled to be removed when `future`s are natively supported.
    would-block,
    /// The operation is not valid in the socket's current state.
    invalid-state,
    /// A new socket resource could not be created because of a system limit.
    new-socket-limit,
    /// A bind operation failed because the provided address is not an address that the `network` can bind to.
    address-not-bindable,
    /// A bind operation failed because the provided address is already in use or because there are no ephemeral ports available.
    address-in-use,
    /// The remote address is not reachable
    remote-unreachable,
    /// The TCP connection was forcefully rejected
    connection-refused,
    /// The TCP connection was reset.
    connection-reset,
    /// A TCP connection was aborted.
    connection-aborted,
    /// The size of a datagram sent to a UDP socket exceeded the maximum
    /// supported size.
    datagram-too-large,
    /// Name does not exist or has no suitable associated IP addresses.
    name-unresolvable,
    /// A temporary failure in name resolution occurred.
    temporary-resolver-failure,
    /// A permanent failure in name resolution occurred.
    permanent-resolver-failure,
  }

  @since(version = 0.2.0)
  enum ip-address-family {
    /// Similar to `AF_INET` in POSIX.
    ipv4,
    /// Similar to `AF_INET6` in POSIX.
    ipv6,
  }

  @since(version = 0.2.0)
  type ipv4-address = tuple<u8, u8, u8, u8>;

  @since(version = 0.2.0)
  type ipv6-address = tuple<u16, u16, u16, u16, u16, u16, u16, u16>;

  @since(version = 0.2.0)
  variant ip-address {
    ipv4(ipv4-address),
    ipv6(ipv6-address),
  }

  @since(version = 0.2.0)
  record ipv4-socket-address {
    /// sin_port
    port: u16,
    /// sin_addr
    address: ipv4-address,
  }

  @since(version = 0.2.0)
  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 = 0.2.0)
  variant ip-socket-address {
    ipv4(ipv4-socket-address),
    ipv6(ipv6-socket-address),
  }

  /// Attempts to extract a network-related `error-code` from the stream
  /// `error` provided.
  ///
  /// Stream operations which return `stream-error::last-operation-failed`
  /// have a payload with more information about the operation that failed.
  /// This payload can be passed through to this function to see if there's
  /// network-related information about the error to return.
  ///
  /// Note that this function is fallible because not all stream-related
  /// errors are network-related errors.
  @unstable(feature = network-error-code)
  network-error-code: func(err: borrow<error>) -> option<error-code>;
}

/// This interface provides a value-export of the default network handle..
@since(version = 0.2.0)
interface instance-network {
  @since(version = 0.2.0)
  use network.{network};

  /// Get a handle to the default network.
  @since(version = 0.2.0)
  instance-network: func() -> network;
}

@since(version = 0.2.0)
interface ip-name-lookup {
  @since(version = 0.2.0)
  use wasi:io/poll@0.2.10.{pollable};
  @since(version = 0.2.0)
  use network.{network, error-code, ip-address};

  @since(version = 0.2.0)
  resource resolve-address-stream {
    /// 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`.
    ///
    /// This function never returns IPv4-mapped IPv6 addresses.
    ///
    /// # Typical errors
    /// - `name-unresolvable`:          Name does not exist or has no suitable associated IP addresses. (EAI_NONAME, EAI_NODATA, EAI_ADDRFAMILY)
    /// - `temporary-resolver-failure`: A temporary failure in name resolution occurred. (EAI_AGAIN)
    /// - `permanent-resolver-failure`: A permanent failure in name resolution occurred. (EAI_FAIL)
    /// - `would-block`:                A result is not available yet. (EWOULDBLOCK, EAGAIN)
    @since(version = 0.2.0)
    resolve-next-address: func() -> result<option<ip-address>, error-code>;
    /// Create a `pollable` which will resolve once the stream is ready for I/O.
    ///
    /// Note: this function is here for WASI 0.2 only.
    /// It's planned to be removed when `future` is natively supported in Preview3.
    @since(version = 0.2.0)
    subscribe: func() -> pollable;
  }

  /// 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.
  ///
  /// This function never blocks. It either immediately fails or immediately
  /// returns successfully with a `resolve-address-stream` that can be used
  /// to (asynchronously) fetch the results.
  ///
  /// # Typical errors
  /// - `invalid-argument`: `name` is a syntactically invalid domain name or IP address.
  ///
  /// # 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 = 0.2.0)
  resolve-addresses: func(network: borrow<network>, name: string) -> result<resolve-address-stream, error-code>;
}

@since(version = 0.2.0)
interface tcp {
  @since(version = 0.2.0)
  use wasi:io/streams@0.2.10.{input-stream, output-stream};
  @since(version = 0.2.0)
  use wasi:io/poll@0.2.10.{pollable};
  @since(version = 0.2.0)
  use wasi:clocks/monotonic-clock@0.2.10.{duration};
  @since(version = 0.2.0)
  use network.{network, error-code, ip-socket-address, ip-address-family};

  @since(version = 0.2.0)
  enum shutdown-type {
    /// Similar to `SHUT_RD` in POSIX.
    receive,
    /// Similar to `SHUT_WR` in POSIX.
    send,
    /// Similar to `SHUT_RDWR` in POSIX.
    both,
  }

  /// A TCP socket resource.
  ///
  /// The socket can be in one of the following states:
  /// - `unbound`
  /// - `bind-in-progress`
  /// - `bound` (See note below)
  /// - `listen-in-progress`
  /// - `listening`
  /// - `connect-in-progress`
  /// - `connected`
  /// - `closed`
  /// See <https://github.com/WebAssembly/wasi-sockets/blob/main/TcpSocketOperationalSemantics.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`, `listen-in-progress`, `listening`, `connect-in-progress` or `connected`)
  ///
  /// In addition to the general error codes documented on the
  /// `network::error-code` type, TCP socket methods may always return
  /// `error(invalid-state)` when in the `closed` state.
  @since(version = 0.2.0)
  resource tcp-socket {
    /// Bind the socket to a specific network on 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 the `network` can bind to. (EADDRNOTAVAIL)
    /// - `not-in-progress`:           A `bind` operation is not in progress.
    /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
    ///
    /// # Implementors note
    /// When binding to a non-zero port, this 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 entirely.
    ///
    /// Unlike in POSIX, in WASI the bind operation is async. This enables
    /// interactive WASI hosts to inject permission prompts. Runtimes that
    /// don't want to make use of this ability can simply call the native
    /// `bind` as part of either `start-bind` or `finish-bind`.
    ///
    /// # 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 = 0.2.0)
    start-bind: func(network: borrow<network>, local-address: ip-socket-address) -> result<_, error-code>;
    @since(version = 0.2.0)
    finish-bind: func() -> result<_, error-code>;
    /// Connect to a remote endpoint.
    ///
    /// On success:
    /// - the socket is transitioned into the `connected` state.
    /// - a pair of streams is returned that can be used to read & write to the connection
    ///
    /// 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-argument`:          The socket is already attached to a different network. The `network` passed to `connect` must be identical to the one passed to `bind`.
    /// - `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)
    /// - `not-in-progress`:           A connect operation is not in progress.
    /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
    ///
    /// # Implementors note
    /// The POSIX equivalent of `start-connect` is the regular `connect` syscall.
    /// Because all WASI sockets are non-blocking this is expected to return
    /// EINPROGRESS, which should be translated to `ok()` in WASI.
    ///
    /// The POSIX equivalent of `finish-connect` is a `poll` for event `POLLOUT`
    /// with a timeout of 0 on the socket descriptor. Followed by a check for
    /// the `SO_ERROR` socket option, in case the poll signaled readiness.
    ///
    /// # 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 = 0.2.0)
    start-connect: func(network: borrow<network>, remote-address: ip-socket-address) -> result<_, error-code>;
    @since(version = 0.2.0)
    finish-connect: func() -> result<tuple<input-stream, output-stream>, error-code>;
    /// Start listening for new connections.
    ///
    /// Transitions the socket into the `listening` state.
    ///
    /// Unlike POSIX, the socket must already be explicitly bound.
    ///
    /// # Typical errors
    /// - `invalid-state`:             The socket is not bound to any local address. (EDESTADDRREQ)
    /// - `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)
    /// - `not-in-progress`:           A listen operation is not in progress.
    /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
    ///
    /// # Implementors note
    /// Unlike in POSIX, in WASI the listen operation is async. This enables
    /// interactive WASI hosts to inject permission prompts. Runtimes that
    /// don't want to make use of this ability can simply call the native
    /// `listen` as part of either `start-listen` or `finish-listen`.
    ///
    /// # References
    /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/listen.html>
    /// - <https://man7.org/linux/man-pages/man2/listen.2.html>
    /// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-listen>
    /// - <https://man.freebsd.org/cgi/man.cgi?query=listen&sektion=2>
    @since(version = 0.2.0)
    start-listen: func() -> result<_, error-code>;
    @since(version = 0.2.0)
    finish-listen: func() -> result<_, error-code>;
    /// Accept a new client socket.
    ///
    /// The returned socket is bound and in the `connected` state. 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`
    ///
    /// On success, this function returns the newly accepted client socket along with
    /// a pair of streams that can be used to read & write to the connection.
    ///
    /// # Typical errors
    /// - `invalid-state`:      Socket is not in the `listening` state. (EINVAL)
    /// - `would-block`:        No pending connections at the moment. (EWOULDBLOCK, EAGAIN)
    /// - `connection-aborted`: An incoming connection was pending, but was terminated by the client before this listener could accept it. (ECONNABORTED)
    /// - `new-socket-limit`:   The new socket resource could not be created because of a system limit. (EMFILE, ENFILE)
    ///
    /// # References
    /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/accept.html>
    /// - <https://man7.org/linux/man-pages/man2/accept.2.html>
    /// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-accept>
    /// - <https://man.freebsd.org/cgi/man.cgi?query=accept&sektion=2>
    @since(version = 0.2.0)
    accept: func() -> result<tuple<tcp-socket, input-stream, output-stream>, 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 `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 = 0.2.0)
    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 = 0.2.0)
    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 = 0.2.0)
    is-listening: func() -> bool;
    /// Whether this is a IPv4 or IPv6 socket.
    ///
    /// Equivalent to the SO_DOMAIN socket option.
    @since(version = 0.2.0)
    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 `connect-in-progress` or `connected` state.
    @since(version = 0.2.0)
    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 = 0.2.0)
    keep-alive-enabled: func() -> result<bool, error-code>;
    @since(version = 0.2.0)
    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.
    /// Any other value will never cause an error, but it might be silently clamped and/or rounded.
    /// I.e. after setting a value, reading the same setting back may return a different value.
    ///
    /// Equivalent to the TCP_KEEPIDLE socket option. (TCP_KEEPALIVE on MacOS)
    ///
    /// # Typical errors
    /// - `invalid-argument`:     (set) The provided value was 0.
    @since(version = 0.2.0)
    keep-alive-idle-time: func() -> result<duration, error-code>;
    @since(version = 0.2.0)
    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.
    /// Any other value will never cause an error, but it might be silently clamped and/or rounded.
    /// I.e. after setting a value, reading the same setting back may return a different value.
    ///
    /// Equivalent to the TCP_KEEPINTVL socket option.
    ///
    /// # Typical errors
    /// - `invalid-argument`:     (set) The provided value was 0.
    @since(version = 0.2.0)
    keep-alive-interval: func() -> result<duration, error-code>;
    @since(version = 0.2.0)
    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.
    /// Any other value will never cause an error, but it might be silently clamped and/or rounded.
    /// I.e. after setting a value, reading the same setting back may return a different value.
    ///
    /// Equivalent to the TCP_KEEPCNT socket option.
    ///
    /// # Typical errors
    /// - `invalid-argument`:     (set) The provided value was 0.
    @since(version = 0.2.0)
    keep-alive-count: func() -> result<u32, error-code>;
    @since(version = 0.2.0)
    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 = 0.2.0)
    hop-limit: func() -> result<u8, error-code>;
    @since(version = 0.2.0)
    set-hop-limit: func(value: u8) -> result<_, error-code>;
    /// The kernel buffer space reserved for sends/receives on this socket.
    ///
    /// 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.
    /// I.e. after setting a value, reading the same setting back may return a different value.
    ///
    /// Equivalent to the SO_RCVBUF and SO_SNDBUF socket options.
    ///
    /// # Typical errors
    /// - `invalid-argument`:     (set) The provided value was 0.
    @since(version = 0.2.0)
    receive-buffer-size: func() -> result<u64, error-code>;
    @since(version = 0.2.0)
    set-receive-buffer-size: func(value: u64) -> result<_, error-code>;
    @since(version = 0.2.0)
    send-buffer-size: func() -> result<u64, error-code>;
    @since(version = 0.2.0)
    set-send-buffer-size: func(value: u64) -> result<_, error-code>;
    /// Create a `pollable` which can be used to poll for, or block on,
    /// completion of any of the asynchronous operations of this socket.
    ///
    /// When `finish-bind`, `finish-listen`, `finish-connect` or `accept`
    /// return `error(would-block)`, this pollable can be used to wait for
    /// their success or failure, after which the method can be retried.
    ///
    /// The pollable is not limited to the async operation that happens to be
    /// in progress at the time of calling `subscribe` (if any). Theoretically,
    /// `subscribe` only has to be called once per socket and can then be
    /// (re)used for the remainder of the socket's lifetime.
    ///
    /// See <https://github.com/WebAssembly/wasi-sockets/blob/main/TcpSocketOperationalSemantics.md#pollable-readiness>
    /// for more information.
    ///
    /// Note: this function is here for WASI 0.2 only.
    /// It's planned to be removed when `future` is natively supported in Preview3.
    @since(version = 0.2.0)
    subscribe: func() -> pollable;
    /// Initiate a graceful shutdown.
    ///
    /// - `receive`: The socket is not expecting to receive any data from
    ///   the peer. The `input-stream` associated with this socket will be
    ///   closed. Any data still in the receive queue at time of calling
    ///   this method will be discarded.
    /// - `send`: The socket has no more data to send to the peer. The `output-stream`
    ///   associated with this socket will be closed and a FIN packet will be sent.
    /// - `both`: Same effect as `receive` & `send` combined.
    ///
    /// This function is idempotent; shutting down a direction more than once
    /// has no effect and returns `ok`.
    ///
    /// The shutdown function does not close (drop) the socket.
    ///
    /// # Typical errors
    /// - `invalid-state`: The socket is not in the `connected` state. (ENOTCONN)
    ///
    /// # References
    /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/shutdown.html>
    /// - <https://man7.org/linux/man-pages/man2/shutdown.2.html>
    /// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-shutdown>
    /// - <https://man.freebsd.org/cgi/man.cgi?query=shutdown&sektion=2>
    @since(version = 0.2.0)
    shutdown: func(shutdown-type: shutdown-type) -> result<_, error-code>;
  }
}

@since(version = 0.2.0)
interface tcp-create-socket {
  @since(version = 0.2.0)
  use network.{network, error-code, ip-address-family};
  @since(version = 0.2.0)
  use tcp.{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.
  ///
  /// This function does not require a network capability handle. This is considered to be safe because
  /// at time of creation, the socket is not bound to any `network` yet. Up to the moment `bind`/`connect`
  /// is called, the socket is effectively an in-memory configuration object, unable to communicate with the outside world.
  ///
  /// All sockets are non-blocking. Use the wasi-poll interface to block on asynchronous operations.
  ///
  /// # Typical errors
  /// - `not-supported`:     The specified `address-family` is not supported. (EAFNOSUPPORT)
  /// - `new-socket-limit`:  The new socket resource could not be created because of a system limit. (EMFILE, ENFILE)
  ///
  /// # 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 = 0.2.0)
  create-tcp-socket: func(address-family: ip-address-family) -> result<tcp-socket, error-code>;
}

@since(version = 0.2.0)
interface udp {
  @since(version = 0.2.0)
  use wasi:io/poll@0.2.10.{pollable};
  @since(version = 0.2.0)
  use network.{network, error-code, ip-socket-address, ip-address-family};

  /// A received datagram.
  @since(version = 0.2.0)
  record incoming-datagram {
    /// The payload.
    ///
    /// Theoretical max size: ~64 KiB. In practice, typically less than 1500 bytes.
    data: list<u8>,
    /// The source address.
    ///
    /// This field is guaranteed to match the remote address the stream was initialized with, if any.
    ///
    /// Equivalent to the `src_addr` out parameter of `recvfrom`.
    remote-address: ip-socket-address,
  }

  /// A datagram to be sent out.
  @since(version = 0.2.0)
  record outgoing-datagram {
    /// The payload.
    data: list<u8>,
    /// The destination address.
    ///
    /// The requirements on this field depend on how the stream was initialized:
    /// - with a remote address: this field must be None or match the stream's remote address exactly.
    /// - without a remote address: this field is required.
    ///
    /// If this value is None, the send operation is equivalent to `send` in POSIX. Otherwise it is equivalent to `sendto`.
    remote-address: option<ip-socket-address>,
  }

  /// A UDP socket handle.
  @since(version = 0.2.0)
  resource udp-socket {
    /// Bind the socket to a specific network on 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 the `network` can bind to. (EADDRNOTAVAIL)
    /// - `not-in-progress`:           A `bind` operation is not in progress.
    /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
    ///
    /// # Implementors note
    /// Unlike in POSIX, in WASI the bind operation is async. This enables
    /// interactive WASI hosts to inject permission prompts. Runtimes that
    /// don't want to make use of this ability can simply call the native
    /// `bind` as part of either `start-bind` or `finish-bind`.
    ///
    /// # 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 = 0.2.0)
    start-bind: func(network: borrow<network>, local-address: ip-socket-address) -> result<_, error-code>;
    @since(version = 0.2.0)
    finish-bind: func() -> result<_, error-code>;
    /// Set up inbound & outbound communication channels, optionally to a specific peer.
    ///
    /// This function only changes the local socket configuration and does not generate any network traffic.
    /// 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`.
    ///
    /// When a `remote-address` is provided, the returned streams are limited to communicating with that specific peer:
    /// - `send` can only be used to send to this destination.
    /// - `receive` will only return datagrams sent from the provided `remote-address`.
    ///
    /// This method may be called multiple times on the same socket to change its association, but
    /// only the most recently returned pair of streams will be operational. Implementations may trap if
    /// the streams returned by a previous invocation haven't been dropped yet before calling `stream` again.
    ///
    /// The POSIX equivalent in pseudo-code is:
    /// ```text
    /// if (was previously connected) {
    /// 	connect(s, AF_UNSPEC)
    /// }
    /// if (remote_address is Some) {
    /// 	connect(s, remote_address)
    /// }
    /// ```
    ///
    /// Unlike in POSIX, the socket must already be explicitly bound.
    ///
    /// # 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-state`:             The socket is not bound.
    /// - `address-in-use`:            Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE, EADDRNOTAVAIL on Linux, EAGAIN on BSD)
    /// - `remote-unreachable`:        The remote address is not reachable. (ECONNRESET, ENETRESET, EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
    /// - `connection-refused`:        The connection was refused. (ECONNREFUSED)
    ///
    /// # 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 = 0.2.0)
    %stream: func(remote-address: option<ip-socket-address>) -> result<tuple<incoming-datagram-stream, outgoing-datagram-stream>, 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 `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 = 0.2.0)
    local-address: func() -> result<ip-socket-address, error-code>;
    /// Get the address the socket is currently streaming to.
    ///
    /// # Typical errors
    /// - `invalid-state`: The socket is not streaming 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 = 0.2.0)
    remote-address: func() -> result<ip-socket-address, error-code>;
    /// Whether this is a IPv4 or IPv6 socket.
    ///
    /// Equivalent to the SO_DOMAIN socket option.
    @since(version = 0.2.0)
    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 = 0.2.0)
    unicast-hop-limit: func() -> result<u8, error-code>;
    @since(version = 0.2.0)
    set-unicast-hop-limit: func(value: u8) -> result<_, error-code>;
    /// The kernel buffer space reserved for sends/receives on this socket.
    ///
    /// 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.
    /// I.e. after setting a value, reading the same setting back may return a different value.
    ///
    /// Equivalent to the SO_RCVBUF and SO_SNDBUF socket options.
    ///
    /// # Typical errors
    /// - `invalid-argument`:     (set) The provided value was 0.
    @since(version = 0.2.0)
    receive-buffer-size: func() -> result<u64, error-code>;
    @since(version = 0.2.0)
    set-receive-buffer-size: func(value: u64) -> result<_, error-code>;
    @since(version = 0.2.0)
    send-buffer-size: func() -> result<u64, error-code>;
    @since(version = 0.2.0)
    set-send-buffer-size: func(value: u64) -> result<_, error-code>;
    /// Create a `pollable` which will resolve once the socket is ready for I/O.
    ///
    /// Note: this function is here for WASI 0.2 only.
    /// It's planned to be removed when `future` is natively supported in Preview3.
    @since(version = 0.2.0)
    subscribe: func() -> pollable;
  }

  @since(version = 0.2.0)
  resource incoming-datagram-stream {
    /// Receive messages on the socket.
    ///
    /// This function attempts to receive up to `max-results` datagrams on the socket without blocking.
    /// The returned list may contain fewer elements than requested, but never more.
    ///
    /// This function returns successfully with an empty list when either:
    /// - `max-results` is 0, or:
    /// - `max-results` is greater than 0, but no results are immediately available.
    /// This function never returns `error(would-block)`.
    ///
    /// # Typical errors
    /// - `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-recv>
    /// - <https://learn.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-recvfrom>
    /// - <https://learn.microsoft.com/en-us/previous-versions/windows/desktop/legacy/ms741687(v=vs.85)>
    /// - <https://man.freebsd.org/cgi/man.cgi?query=recv&sektion=2>
    @since(version = 0.2.0)
    receive: func(max-results: u64) -> result<list<incoming-datagram>, error-code>;
    /// Create a `pollable` which will resolve once the stream is ready to receive again.
    ///
    /// Note: this function is here for WASI 0.2 only.
    /// It's planned to be removed when `future` is natively supported in Preview3.
    @since(version = 0.2.0)
    subscribe: func() -> pollable;
  }

  @since(version = 0.2.0)
  resource outgoing-datagram-stream {
    /// Check readiness for sending. This function never blocks.
    ///
    /// Returns the number of datagrams permitted for the next call to `send`,
    /// or an error. Calling `send` with more datagrams than this function has
    /// permitted will trap.
    ///
    /// When this function returns ok(0), the `subscribe` pollable will
    /// become ready when this function will report at least ok(1), or an
    /// error.
    ///
    /// Never returns `would-block`.
    check-send: func() -> result<u64, error-code>;
    /// Send messages on the socket.
    ///
    /// This function attempts to send all provided `datagrams` on the socket without blocking and
    /// returns how many messages were actually sent (or queued for sending). This function never
    /// returns `error(would-block)`. If none of the datagrams were able to be sent, `ok(0)` is returned.
    ///
    /// This function semantically behaves the same as iterating the `datagrams` list and sequentially
    /// sending each individual datagram until either the end of the list has been reached or the first error occurred.
    /// If at least one datagram has been sent successfully, this function never returns an error.
    ///
    /// If the input list is empty, the function returns `ok(0)`.
    ///
    /// Each call to `send` must be permitted by a preceding `check-send`. Implementations must trap if
    /// either `check-send` was not called or `datagrams` contains more items than `check-send` permitted.
    ///
    /// # 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 `stream`. (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)
    ///
    /// # 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 = 0.2.0)
    send: func(datagrams: list<outgoing-datagram>) -> result<u64, error-code>;
    /// Create a `pollable` which will resolve once the stream is ready to send again.
    ///
    /// Note: this function is here for WASI 0.2 only.
    /// It's planned to be removed when `future` is natively supported in Preview3.
    @since(version = 0.2.0)
    subscribe: func() -> pollable;
  }
}

@since(version = 0.2.0)
interface udp-create-socket {
  @since(version = 0.2.0)
  use network.{network, error-code, ip-address-family};
  @since(version = 0.2.0)
  use udp.{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.
  ///
  /// This function does not require a network capability handle. This is considered to be safe because
  /// at time of creation, the socket is not bound to any `network` yet. Up to the moment `bind` is called,
  /// the socket is effectively an in-memory configuration object, unable to communicate with the outside world.
  ///
  /// All sockets are non-blocking. Use the wasi-poll interface to block on asynchronous operations.
  ///
  /// # Typical errors
  /// - `not-supported`:     The specified `address-family` is not supported. (EAFNOSUPPORT)
  /// - `new-socket-limit`:  The new socket resource could not be created because of a system limit. (EMFILE, ENFILE)
  ///
  /// # 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 = 0.2.0)
  create-udp-socket: func(address-family: ip-address-family) -> result<udp-socket, error-code>;
}

@since(version = 0.2.0)
world imports {
  @since(version = 0.2.0)
  import wasi:io/error@0.2.10;
  @since(version = 0.2.0)
  import network;
  @since(version = 0.2.0)
  import instance-network;
  @since(version = 0.2.0)
  import wasi:io/poll@0.2.10;
  @since(version = 0.2.0)
  import udp;
  @since(version = 0.2.0)
  import udp-create-socket;
  @since(version = 0.2.0)
  import wasi:io/streams@0.2.10;
  @since(version = 0.2.0)
  import wasi:clocks/monotonic-clock@0.2.10;
  @since(version = 0.2.0)
  import tcp;
  @since(version = 0.2.0)
  import tcp-create-socket;
  @since(version = 0.2.0)
  import ip-name-lookup;
}
