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//
// rhctl
//
// Copyright (C) 2009-2016 Christian Pointner <equinox@helsinki.at>
//
// This file is part of rhctl.
//
// rhctl 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
// any later version.
//
// rhctl 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 rhctl. If not, see <http://www.gnu.org/licenses/>.
//
package main
import (
"net"
)
const (
CLIENT_MAX_DATA_BYTES = 64 * 1024 // close connection if the client sends more then 64k of data
)
type NopTCPInterface struct {
ln net.Listener
ctrl *SwitchControl
}
type Close bool
func readData(con net.Conn, ch chan<- interface{}) {
defer func() {
ch <- Close(false)
}()
bytesRead := 0
for {
var null [1024]byte
n, err := con.Read(null[:])
if err != nil {
return
}
bytesRead = bytesRead + n
if bytesRead > CLIENT_MAX_DATA_BYTES {
rhdl.Printf("NopTCP: client(%s) sent too many bytes", con.RemoteAddr())
return
}
}
}
func handleClient(con net.Conn, ctrl *SwitchControl) {
defer func() {
con.Close()
rhdl.Printf("NopTCP: client(%s) disconnected", con.RemoteAddr())
}()
var ch = ctrl.Updates.Sub()
defer ctrl.Updates.Unsub(ch)
go readData(con, ch)
ctrl.Updates.AddSub(ch, "state")
ctrl.Commands <- &Command{Type: CmdState, Response: ch}
for {
data, ok := <-ch
if !ok {
return
}
switch data.(type) {
case State:
state := data.(State)
if state.ActiveServer == "" {
state.ActiveServer = "none"
}
if _, err := con.Write([]byte(state.ActiveServer + "\n")); err != nil {
break
}
case Close:
return
}
}
}
func (nop *NopTCPInterface) Run() {
rhdl.Printf("NopTCP: handler running...")
for {
con, err := nop.ln.Accept()
if err != nil {
switch err.(type) {
case *net.OpError:
if !err.(*net.OpError).Temporary() {
rhl.Printf("NopTCP: server exiting: %s", err)
return
}
default:
rhl.Printf("NopTCP: server exiting: %s", err)
return
}
}
rhdl.Printf("NopTCP: client(%s) connected", con.RemoteAddr())
go handleClient(con, nop.ctrl)
}
}
func NopTCPInit(conf *Config, ctrl *SwitchControl) (nop *NopTCPInterface, err error) {
nop = &NopTCPInterface{}
nop.ctrl = ctrl
if nop.ln, err = net.Listen("tcp", conf.Clients.Noptcp.Address); err != nil {
return
}
rhdl.Printf("NopTCP: listening on %s", nop.ln.Addr())
return
}
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