// raw packet encapsulation and put it online
func (buf *Buffer) raw_send(data []byte) bool {
// combine output
sz := len(data)
binary.BigEndian.PutUint16(buf.cache, uint16(sz))
copy(buf.cache[2:], data)
// write data
n, err := buf.conn.Write(buf.cache[:sz+2])
if err != nil {
log.Warningf("Error send reply data, bytes: %v reason: %v", n, err)
return false
}
return true
}
// start a goroutine when a new connection is accepted
func handleClient(conn *net.TCPConn) {
defer utils.PrintPanicStack()
// set per-connection socket buffer
conn.SetReadBuffer(SO_RCVBUF)
// set initial socket buffer
conn.SetWriteBuffer(SO_SNDBUF)
// initial network control struct
header := make([]byte, 2)
in := make(chan []byte)
defer func() {
close(in) // session will close
}()
// create a new session object for the connection
var sess Session
host, port, err := net.SplitHostPort(conn.RemoteAddr().String())
if err != nil {
log.Error("cannot get remote address:", err)
return
}
sess.IP = net.ParseIP(host)
log.Infof("new connection from:%v port:%v", host, port)
// session die signal
sess_die := make(chan bool)
// create a write buffer
out := new_buffer(conn, sess_die)
go out.start()
// start one agent for handling packet
wg.Add(1)
go agent(&sess, in, out, sess_die)
// network loop
for {
// solve dead link problem
conn.SetReadDeadline(time.Now().Add(TCP_READ_DEADLINE * time.Second))
n, err := io.ReadFull(conn, header)
if err != nil {
log.Warningf("read header failed, ip:%v reason:%v size:%v", sess.IP, err, n)
return
}
size := binary.BigEndian.Uint16(header)
// alloc a byte slice for reading
payload := make([]byte, size)
// read msg
n, err = io.ReadFull(conn, payload)
if err != nil {
log.Warningf("read payload failed, ip:%v reason:%v size:%v", sess.IP, err, n)
return
}
select {
case in <- payload: // payload queued
case <-sess_die:
log.Warningf("connection closed by logic, flag:%v ip:%v", sess.Flag, sess.IP)
return
}
}
}