/// Returns `true` if the connection is done.
Returns `true` if the connection is done.
Returns ` true ` if the connection is done .
fn handle_connection_event(
    registry: &Registry,
    connection: &mut TcpStream,
    event: &Event,
) -> io::Result<bool> {
    if event.is_writable() {
        // We can (maybe) write to the connection.
        match connection.write(DATA) {
            // We want to write the entire `DATA` buffer in a single go. If we
            // write less we'll return a short write error (same as
            // `io::Write::write_all` does).
            Ok(n) if n < DATA.len() => return Err(io::ErrorKind::WriteZero.into()),
            Ok(_) => {
                // After we've written something we'll reregister the connection
                // to only respond to readable events.
                registry.reregister(connection, event.token(), Interest::READABLE)?
            }
            // Would block "errors" are the OS's way of saying that the
            // connection is not actually ready to perform this I/O operation.
            Err(ref err) if would_block(err) => {}
            // Got interrupted (how rude!), we'll try again.
            Err(ref err) if interrupted(err) => {
                return handle_connection_event(registry, connection, event)
            }
            // Other errors we'll consider fatal.
            Err(err) => return Err(err),
        }
    }
    if event.is_readable() {
        let mut connection_closed = false;
        let mut received_data = vec![0; 4096];
        let mut bytes_read = 0;
        // We can (maybe) read from the connection.
        loop {
            match connection.read(&mut received_data[bytes_read..]) {
                Ok(0) => {
                    // Reading 0 bytes means the other side has closed the
                    // connection or is done writing, then so are we.
                    connection_closed = true;
                    break;
                }
                Ok(n) => {
                    // echo back what we received and ignore any errors while doing so
                    let _ = connection.write_all(&received_data[bytes_read..(bytes_read + n)]);
                    bytes_read += n;
                    if bytes_read == received_data.len() {
                        received_data.resize(received_data.len() + 1024, 0);
                    }
                }
                // Would block "errors" are the OS's way of saying that the
                // connection is not actually ready to perform this I/O operation.
                Err(ref err) if would_block(err) => break,
                Err(ref err) if interrupted(err) => continue,
                // Other errors we'll consider fatal.
                Err(err) => return Err(err),
            }
        }
        if bytes_read != 0 {
            let received_data = &received_data[..bytes_read];
            if let Ok(str_buf) = from_utf8(received_data) {
                println!("Received data: {}", str_buf.trim_end());
            } else {
                println!("Received (none UTF-8) data: {:?}", received_data);
            }
        }
        if connection_closed {
            println!("Connection closed");
            return Ok(true);
        }
    }
    Ok(false)
}
fn handle_connection_event ( registry : & Registry , connection : & mut TcpStream , event : & Event , ) -> io :: Result < bool > { if event . is_writable ( ) { // We can (maybe) write to the connection. match connection . write ( DATA ) { // We want to write the entire `DATA` buffer in a single go. If we // write less we'll return a short write error (same as // `io::Write::write_all` does). Ok ( n ) if n < DATA . len ( ) => return Err ( io :: ErrorKind :: WriteZero . into ( ) ) , Ok ( _ ) => { // After we've written something we'll reregister the connection // to only respond to readable events. registry . reregister ( connection , event . token ( ) , Interest :: READABLE ) ? } // Would block "errors" are the OS's way of saying that the // connection is not actually ready to perform this I/O operation. Err ( ref err ) if would_block ( err ) => { } // Got interrupted (how rude!), we'll try again. Err ( ref err ) if interrupted ( err ) => { return handle_connection_event ( registry , connection , event ) } // Other errors we'll consider fatal. Err ( err ) => return Err ( err ) , } } if event . is_readable ( ) { let mut connection_closed = false ; let mut received_data = vec ! [ 0 4096 ] ; let mut bytes_read = 0 ; // We can (maybe) read from the connection. loop { match connection . read ( & mut received_data [ bytes_read .. ] ) { Ok ( 0 ) => { // Reading 0 bytes means the other side has closed the // connection or is done writing, then so are we. connection_closed = true ; break ; } Ok ( n ) => { // echo back what we received and ignore any errors while doing so let _ = connection . write_all ( & received_data [ bytes_read .. ( bytes_read + n ) ] ) ; bytes_read += n ; if bytes_read == received_data . len ( ) { received_data . resize ( received_data . len ( ) + 1024 , 0 ) ; } } // Would block "errors" are the OS's way of saying that the // connection is not actually ready to perform this I/O operation. Err ( ref err ) if would_block ( err ) => break , Err ( ref err ) if interrupted ( err ) => continue , // Other errors we'll consider fatal. Err ( err ) => return Err ( err ) , } } if bytes_read != 0 { let received_data = & received_data [ .. bytes_read ] ; if let Ok ( str_buf ) = from_utf8 ( received_data ) { println ! ( " " str_buf trim_end ( ) ) ; } else { println ! ( " " received_data ) ; } } if connection_closed { println ! ( " " ) ; return Ok ( true ) ; } } Ok ( false ) }
Returns `true` if the connection is done.
Returns ` true ` if the connection is done .
registry
&Registry
connection
&mut TcpStream
event
&Event