openethereum/util/io/src/lib.rs
2017-06-22 19:00:53 +02:00

173 lines
5.2 KiB
Rust

// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
//! General IO module.
//!
//! Example usage for creating a network service and adding an IO handler:
//!
//! ```rust
//! extern crate ethcore_io;
//! use ethcore_io::*;
//! use std::sync::Arc;
//!
//! struct MyHandler;
//!
//! #[derive(Clone)]
//! struct MyMessage {
//! data: u32
//! }
//!
//! impl IoHandler<MyMessage> for MyHandler {
//! fn initialize(&self, io: &IoContext<MyMessage>) {
//! io.register_timer(0, 1000).unwrap();
//! }
//!
//! fn timeout(&self, _io: &IoContext<MyMessage>, timer: TimerToken) {
//! println!("Timeout {}", timer);
//! }
//!
//! fn message(&self, _io: &IoContext<MyMessage>, message: &MyMessage) {
//! println!("Message {}", message.data);
//! }
//! }
//!
//! fn main () {
//! let mut service = IoService::<MyMessage>::start().expect("Error creating network service");
//! service.register_handler(Arc::new(MyHandler)).unwrap();
//!
//! // Wait for quit condition
//! // ...
//! // Drop the service
//! }
//! ```
//TODO: use Poll from mio
#![allow(deprecated)]
extern crate mio;
#[macro_use]
extern crate log as rlog;
extern crate slab;
extern crate crossbeam;
extern crate parking_lot;
mod service;
mod worker;
use mio::{Token};
use mio::deprecated::{EventLoop, NotifyError};
use std::fmt;
pub use worker::LOCAL_STACK_SIZE;
#[derive(Debug)]
/// IO Error
pub enum IoError {
/// Low level error from mio crate
Mio(::std::io::Error),
/// Error concerning the Rust standard library's IO subsystem.
StdIo(::std::io::Error),
}
impl fmt::Display for IoError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
// just defer to the std implementation for now.
// we can refine the formatting when more variants are added.
match *self {
IoError::Mio(ref std_err) => std_err.fmt(f),
IoError::StdIo(ref std_err) => std_err.fmt(f),
}
}
}
impl From<::std::io::Error> for IoError {
fn from(err: ::std::io::Error) -> IoError {
IoError::StdIo(err)
}
}
impl<Message> From<NotifyError<service::IoMessage<Message>>> for IoError where Message: Send + Clone {
fn from(_err: NotifyError<service::IoMessage<Message>>) -> IoError {
IoError::Mio(::std::io::Error::new(::std::io::ErrorKind::ConnectionAborted, "Network IO notification error"))
}
}
/// Generic IO handler.
/// All the handler function are called from within IO event loop.
/// `Message` type is used as notification data
pub trait IoHandler<Message>: Send + Sync where Message: Send + Sync + Clone + 'static {
/// Initialize the handler
fn initialize(&self, _io: &IoContext<Message>) {}
/// Timer function called after a timeout created with `HandlerIo::timeout`.
fn timeout(&self, _io: &IoContext<Message>, _timer: TimerToken) {}
/// Called when a broadcasted message is received. The message can only be sent from a different IO handler.
fn message(&self, _io: &IoContext<Message>, _message: &Message) {}
/// Called when an IO stream gets closed
fn stream_hup(&self, _io: &IoContext<Message>, _stream: StreamToken) {}
/// Called when an IO stream can be read from
fn stream_readable(&self, _io: &IoContext<Message>, _stream: StreamToken) {}
/// Called when an IO stream can be written to
fn stream_writable(&self, _io: &IoContext<Message>, _stream: StreamToken) {}
/// Register a new stream with the event loop
fn register_stream(&self, _stream: StreamToken, _reg: Token, _event_loop: &mut EventLoop<IoManager<Message>>) {}
/// Re-register a stream with the event loop
fn update_stream(&self, _stream: StreamToken, _reg: Token, _event_loop: &mut EventLoop<IoManager<Message>>) {}
/// Deregister a stream. Called whenstream is removed from event loop
fn deregister_stream(&self, _stream: StreamToken, _event_loop: &mut EventLoop<IoManager<Message>>) {}
}
pub use service::TimerToken;
pub use service::StreamToken;
pub use service::IoContext;
pub use service::IoService;
pub use service::IoChannel;
pub use service::IoManager;
pub use service::TOKENS_PER_HANDLER;
#[cfg(test)]
mod tests {
use std::sync::Arc;
use super::*;
struct MyHandler;
#[derive(Clone)]
struct MyMessage {
data: u32
}
impl IoHandler<MyMessage> for MyHandler {
fn initialize(&self, io: &IoContext<MyMessage>) {
io.register_timer(0, 1000).unwrap();
}
fn timeout(&self, _io: &IoContext<MyMessage>, timer: TimerToken) {
println!("Timeout {}", timer);
}
fn message(&self, _io: &IoContext<MyMessage>, message: &MyMessage) {
println!("Message {}", message.data);
}
}
#[test]
fn test_service_register_handler () {
let service = IoService::<MyMessage>::start().expect("Error creating network service");
service.register_handler(Arc::new(MyHandler)).unwrap();
}
}