gost_software/server.go
2017-08-13 09:30:18 +08:00

119 lines
2.0 KiB
Go

package gost
import (
"io"
"net"
"time"
"github.com/go-log/log"
)
// Server is a proxy server.
type Server struct {
Listener Listener
}
// Addr returns the address of the server
func (s *Server) Addr() net.Addr {
return s.Listener.Addr()
}
// Close closes the server
func (s *Server) Close() error {
return s.Listener.Close()
}
// Serve serves as a proxy server.
func (s *Server) Serve(h Handler) error {
if s.Listener == nil {
ln, err := TCPListener("")
if err != nil {
return err
}
s.Listener = ln
}
if h == nil {
h = HTTPHandler()
}
l := s.Listener
var tempDelay time.Duration
for {
conn, e := l.Accept()
if e != nil {
if ne, ok := e.(net.Error); ok && ne.Temporary() {
if tempDelay == 0 {
tempDelay = 5 * time.Millisecond
} else {
tempDelay *= 2
}
if max := 1 * time.Second; tempDelay > max {
tempDelay = max
}
log.Logf("server: Accept error: %v; retrying in %v", e, tempDelay)
time.Sleep(tempDelay)
continue
}
return e
}
tempDelay = 0
go h.Handle(conn)
}
}
// Listener is a proxy server listener, just like a net.Listener.
type Listener interface {
net.Listener
}
type tcpListener struct {
net.Listener
}
// TCPListener creates a Listener for TCP proxy server.
func TCPListener(addr string) (Listener, error) {
laddr, err := net.ResolveTCPAddr("tcp", addr)
if err != nil {
return nil, err
}
ln, err := net.ListenTCP("tcp", laddr)
if err != nil {
return nil, err
}
return &tcpListener{Listener: tcpKeepAliveListener{ln}}, nil
}
type tcpKeepAliveListener struct {
*net.TCPListener
}
func (ln tcpKeepAliveListener) Accept() (c net.Conn, err error) {
tc, err := ln.AcceptTCP()
if err != nil {
return
}
tc.SetKeepAlive(true)
tc.SetKeepAlivePeriod(KeepAliveTime)
return tc, nil
}
func transport(rw1, rw2 io.ReadWriter) error {
errc := make(chan error, 1)
go func() {
_, err := io.Copy(rw1, rw2)
errc <- err
}()
go func() {
_, err := io.Copy(rw2, rw1)
errc <- err
}()
err := <-errc
if err != nil && err == io.EOF {
err = nil
}
return err
}