diff --git a/client/Makefile b/client/Makefile index 35dfe19..48c3976 100644 --- a/client/Makefile +++ b/client/Makefile @@ -9,6 +9,7 @@ GOFILES=\ connection.go\ commands.go\ handlers.go\ + line.go\ nickchan.go include $(GOROOT)/src/Make.pkg diff --git a/client/connection.go b/client/connection.go index 2202094..73706f3 100644 --- a/client/connection.go +++ b/client/connection.go @@ -10,6 +10,10 @@ import ( "time" ) +const ( + second = int64(1e9) +) + // An IRC connection is represented by this struct. Once connected, any errors // encountered are piped down *Conn.Err; this channel is closed on disconnect. type Conn struct { @@ -32,6 +36,9 @@ type Conn struct { out chan string connected bool + // Control channels to goroutines + cSend, cLoop chan bool + // Error channel to transmit any fail back to the user Err chan os.Error @@ -40,9 +47,15 @@ type Conn struct { SSL bool SSLConfig *tls.Config + // Socket timeout, in seconds. Defaulted to 5m in New(). + Timeout int64 + // Set this to true to disable flood protection and false to re-enable Flood bool + // Internal counters for flood protection + badness, lastsent int64 + // Function which returns a *time.Time for use as a timestamp Timestamp func() *time.Time @@ -51,43 +64,38 @@ type Conn struct { TSFormat string } -// We parse an incoming line into this struct. Line.Cmd is used as the trigger -// name for incoming event handlers, see *Conn.recv() for details. -// Raw =~ ":nick!user@host cmd args[] :text" -// Src == "nick!user@host" -// Cmd == e.g. PRIVMSG, 332 -type Line struct { - Nick, Ident, Host, Src string - Cmd, Raw string - Args []string - Time *time.Time -} - // Creates a new IRC connection object, but doesn't connect to anything so // that you can add event handlers to it. See AddHandler() for details. func New(nick, user, name string) *Conn { - conn := new(Conn) + conn := &Conn{ + in: make(chan *Line, 32), + out: make(chan string, 32), + Err: make(chan os.Error, 4), + cSend: make(chan bool), + cLoop: make(chan bool), + SSL: false, + SSLConfig: nil, + Timeout: 300, + Flood: false, + badness: 0, + lastsent: 0, + Timestamp: time.LocalTime, + TSFormat: "15:04:05", + } conn.initialise() - conn.SSL = false - conn.SSLConfig = nil - conn.Me = conn.NewNick(nick, user, name, "") - conn.Timestamp = time.LocalTime - conn.TSFormat = "15:04:05" conn.setupEvents() + conn.Me = conn.NewNick(nick, user, name, "") return conn } +// Per-connection state initialisation. func (conn *Conn) initialise() { - // allocate meh some memoraaaahh conn.nicks = make(map[string]*Nick) conn.chans = make(map[string]*Channel) - conn.in = make(chan *Line, 32) - conn.out = make(chan string, 32) - conn.Err = make(chan os.Error, 4) conn.io = nil conn.sock = nil - // if this is being called because we are reconnecting, conn.Me + // If this is being called because we are reconnecting, conn.Me // will still have all the old channels referenced -- nuke them! if conn.Me != nil { conn.Me = conn.NewNick(conn.Me.Nick, conn.Me.Ident, conn.Me.Name, "") @@ -110,18 +118,8 @@ func (conn *Conn) Connect(host string, pass ...string) os.Error { if !hasPort(host) { host += ":6697" } - // It's unfortunate that tls.Dial doesn't allow a tls.Config arg, - // so we simply replicate it here with the correct Config. - // http://codereview.appspot.com/2883041 - if s, err := net.Dial("tcp", host); err == nil { - // Passing nil config => certs are validated. - c := tls.Client(s, conn.SSLConfig) - if err = c.Handshake(); err == nil { - conn.sock = c - } else { - s.Close() - return err - } + if s, err := tls.Dial("tcp", host, conn.SSLConfig); err == nil { + conn.sock = s } else { return err } @@ -140,7 +138,8 @@ func (conn *Conn) Connect(host string, pass ...string) os.Error { conn.io = bufio.NewReadWriter( bufio.NewReader(conn.sock), bufio.NewWriter(conn.sock)) - conn.sock.SetTimeout(300000000000) // 5 minutes + conn.sock.SetTimeout(conn.Timeout * second) + conn.connected = true go conn.send() go conn.recv() @@ -164,38 +163,15 @@ func hasPort(s string) bool { return strings.LastIndex(s, ":") > strings.LastIndex(s, "]") } -// dispatch input from channel as \r\n terminated line to peer -// flood controlled using hybrid's algorithm if conn.Flood is true +// goroutine to pass data from output channel to write() func (conn *Conn) send() { - lastsent := time.Nanoseconds() - var badness, linetime, second int64 = 0, 0, 1000000000 - for line := range conn.out { - // Hybrid's algorithm allows for 2 seconds per line and an additional - // 1/120 of a second per character on that line. - linetime = 2*second + int64(len(line))*second/120 - if !conn.Flood && conn.connected { - // No point in tallying up flood protection stuff until connected - if badness += linetime + lastsent - time.Nanoseconds(); badness < 0 { - // negative badness times are badness... - badness = int64(0) - } - } - lastsent = time.Nanoseconds() - - // If we've sent more than 10 second's worth of lines according to the - // calculation above, then we're at risk of "Excess Flood". - if badness > 10*second && !conn.Flood { - // so sleep for the current line's time value before sending it - time.Sleep(linetime) - } - if _, err := conn.io.WriteString(line + "\r\n"); err != nil { - conn.error("irc.send(): %s", err.String()) - conn.shutdown() - break - } - conn.io.Flush() - if conn.Debug { - fmt.Println(conn.Timestamp().Format(conn.TSFormat) + " -> " + line) + for { + select { + case line := <-conn.out: + conn.write(line) + case <-conn.cSend: + // strobe on control channel, bail out + return } } } @@ -204,70 +180,86 @@ func (conn *Conn) send() { func (conn *Conn) recv() { for { s, err := conn.io.ReadString('\n') - t := conn.Timestamp() if err != nil { conn.error("irc.recv(): %s", err.String()) conn.shutdown() break } s = strings.Trim(s, "\r\n") + t := conn.Timestamp() if conn.Debug { fmt.Println(t.Format(conn.TSFormat) + " <- " + s) } - line := &Line{Raw: s, Time: t} - if s[0] == ':' { - // remove a source and parse it - if idx := strings.Index(s, " "); idx != -1 { - line.Src, s = s[1:idx], s[idx+1:len(s)] - } else { - // pretty sure we shouldn't get here ... - line.Src = s[1:len(s)] - conn.in <- line - continue - } - - // src can be the hostname of the irc server or a nick!user@host - line.Host = line.Src - nidx, uidx := strings.Index(line.Src, "!"), strings.Index(line.Src, "@") - if uidx != -1 && nidx != -1 { - line.Nick = line.Src[0:nidx] - line.Ident = line.Src[nidx+1 : uidx] - line.Host = line.Src[uidx+1 : len(line.Src)] - } - } - - // now we're here, we've parsed a :nick!user@host or :server off - // s should contain "cmd args[] :text" - args := strings.Split(s, " :", 2) - if len(args) > 1 { - args = append(strings.Fields(args[0]), args[1]) - } else { - args = strings.Fields(args[0]) - } - line.Cmd = strings.ToUpper(args[0]) - if len(args) > 1 { - line.Args = args[1:len(args)] - } + line := parseLine(s) + line.Time = t conn.in <- line } } +// goroutine to dispatch events for lines received on input channel func (conn *Conn) runLoop() { - for line := range conn.in { - conn.dispatchEvent(line) + for { + select { + case line := <-conn.in: + conn.dispatchEvent(line) + case <-conn.cLoop: + // strobe on control channel, bail out + return + } + } +} + +// Write a \r\n terminated line of output to the connected server, +// using Hybrid's algorithm to rate limit if conn.Flood is false. +func (conn *Conn) write(line string) { + if !conn.Flood { + conn.rateLimit(int64(len(line))) + } + + if _, err := conn.io.WriteString(line + "\r\n"); err != nil { + conn.error("irc.send(): %s", err.String()) + conn.shutdown() + return + } + conn.io.Flush() + if conn.Debug { + fmt.Println(conn.Timestamp().Format(conn.TSFormat) + " -> " + line) + } +} + +// Implement Hybrid's flood control algorithm to rate-limit outgoing lines. +func (conn *Conn) rateLimit(chars int64) { + // Hybrid's algorithm allows for 2 seconds per line and an additional + // 1/120 of a second per character on that line. + linetime := 2*second + chars*second/120 + elapsed := time.Nanoseconds() - conn.lastsent + if conn.badness += linetime - elapsed; conn.badness < 0 { + // negative badness times are badness... + conn.badness = int64(0) + } + conn.lastsent = time.Nanoseconds() + // If we've sent more than 10 second's worth of lines according to the + // calculation above, then we're at risk of "Excess Flood". + if conn.badness > 10*second && !conn.Flood { + // so sleep for the current line's time value before sending it + time.Sleep(linetime) } } func (conn *Conn) shutdown() { - close(conn.in) - close(conn.out) - close(conn.Err) - conn.connected = false - conn.sock.Close() - // reinit datastructures ready for next connection - // do this here rather than after runLoop()'s for due to race - conn.initialise() + // Guard against double-call of shutdown() if we get an error in send() + // as calling sock.Close() will cause recv() to recieve EOF in readstring() + if conn.connected { + conn.connected = false + conn.sock.Close() + conn.cSend <- true + conn.cLoop <- true + conn.dispatchEvent(&Line{Cmd: "DISCONNECTED"}) + // reinit datastructures ready for next connection + // do this here rather than after runLoop()'s for due to race + conn.initialise() + } } // Dumps a load of information about the current state of the connection to a diff --git a/client/handlers.go b/client/handlers.go index 3745ffd..f6f0f8b 100644 --- a/client/handlers.go +++ b/client/handlers.go @@ -76,7 +76,6 @@ func (conn *Conn) h_PING(line *Line) { // Handler to trigger a "CONNECTED" event on receipt of numeric 001 func (conn *Conn) h_001(line *Line) { // we're connected! - conn.connected = true conn.dispatchEvent(&Line{Cmd: "CONNECTED"}) // and we're being given our hostname (from the server's perspective) t := line.Args[len(line.Args)-1] @@ -103,7 +102,7 @@ func (conn *Conn) h_433(line *Line) { // if this is happening before we're properly connected (i.e. the nick // we sent in the initial NICK command is in use) we will not receive // a NICK message to confirm our change of nick, so ReNick here... - if !conn.connected && line.Args[1] == conn.Me.Nick { + if line.Args[1] == conn.Me.Nick { conn.Me.ReNick(line.Args[1] + "_") } } diff --git a/client/line.go b/client/line.go new file mode 100644 index 0000000..d644add --- /dev/null +++ b/client/line.go @@ -0,0 +1,56 @@ +package client + +import ( + "strings" + "time" +) + +// We parse an incoming line into this struct. Line.Cmd is used as the trigger +// name for incoming event handlers, see *Conn.recv() for details. +// Raw =~ ":nick!user@host cmd args[] :text" +// Src == "nick!user@host" +// Cmd == e.g. PRIVMSG, 332 +type Line struct { + Nick, Ident, Host, Src string + Cmd, Raw string + Args []string + Time *time.Time +} + +func parseLine(s string) *Line { + line := &Line{Raw: s} + if s[0] == ':' { + // remove a source and parse it + if idx := strings.Index(s, " "); idx != -1 { + line.Src, s = s[1:idx], s[idx+1:len(s)] + } else { + // pretty sure we shouldn't get here ... + line.Src = s[1:len(s)] + return line + } + + // src can be the hostname of the irc server or a nick!user@host + line.Host = line.Src + nidx, uidx := strings.Index(line.Src, "!"), strings.Index(line.Src, "@") + if uidx != -1 && nidx != -1 { + line.Nick = line.Src[0:nidx] + line.Ident = line.Src[nidx+1 : uidx] + line.Host = line.Src[uidx+1 : len(line.Src)] + } + } + + // now we're here, we've parsed a :nick!user@host or :server off + // s should contain "cmd args[] :text" + args := strings.Split(s, " :", 2) + if len(args) > 1 { + args = append(strings.Fields(args[0]), args[1]) + } else { + args = strings.Fields(args[0]) + } + line.Cmd = strings.ToUpper(args[0]) + if len(args) > 1 { + line.Args = args[1:len(args)] + } + return line +} +