transport

type Codec interface {
	Encode(*capnp.Message) error
	Decode() (*capnp.Message, error)
	Close() error
}

type IncomingMessage interface {
	Message() rpccp.Message
	Release()
}

type OutgoingMessage interface {
	Send() error
	Message() rpccp.Message
	Release()
}

type Transport interface {
	// NewMessage allocates a new message to be sent over the transport.
	// The caller must call OutgoingMessage.Release() when it no longer
	// needs to reference the message. Calling Release() more than once
	// has no effect.  Before releasing the message, Send() MAY be called
	// at most once to send the mssage.
	//
	// When Release() is called, the underlying *capnp.Message SHOULD be
	// released.  This will also release any clients in the CapTable and
	// release its Arena.
	//
	// The Arena in the returned message should be fast at allocating new
	// segments.  The returned ReleaseFunc MUST be safe to call concurrently
	// with subsequent calls to NewMessage.
	NewMessage() (OutgoingMessage, error)

	// RecvMessage receives the next message sent from the remote vat.
	// The returned message is only valid until the release method is
	// called.  The IncomingMessage.Release() method may be called
	// concurrently with RecvMessage or with any other release function
	// returned by RecvMessage.
	//
	// When Release() is called, the underlying *capnp.Message SHOULD be
	// released.  This will also release any clients in the CapTable and
	// release its Arena.
	//
	// The Arena in the returned message should not fetch segments lazily;
	// the Arena should be fast to access other segments.
	RecvMessage() (IncomingMessage, error)

	// Close releases any resources associated with the transport. If there
	// are any outstanding calls to NewMessage, a returned send function,
	// or RecvMessage, they will be interrupted and return errors.
	Close() error
}