75 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Go
		
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Go
		
	
	
| package listener
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| 
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| import (
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| 	"fmt"
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| 	"net"
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| 	"os"
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| 	"time"
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| )
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| 
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| // tcpKeepAliveListener sets TCP keep-alive timeouts on accepted
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| // connections. It's used by ListenAndServe and ListenAndServeTLS so
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| // dead TCP connections (e.g. closing laptop mid-download) eventually
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| // go away.
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| // it is a plain copy-paste from net/http/server.go
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| type tcpKeepAliveListener struct {
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| 	*net.TCPListener
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| }
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| 
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| func (ln tcpKeepAliveListener) Accept() (c net.Conn, err error) {
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| 	tc, err := ln.AcceptTCP()
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| 	if err != nil {
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| 		return
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| 	}
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| 	tc.SetKeepAlive(true)
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| 	tc.SetKeepAlivePeriod(3 * time.Minute)
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| 	return tc, nil
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| }
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| 
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| // NewListener announces on laddr and net. Accepted values of the net are
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| // 'unix' and 'tcp'
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| func NewListener(net, laddr string) (net.Listener, error) {
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| 	switch net {
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| 	case "unix":
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| 		return newUnixListener(laddr)
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| 	case "tcp", "": // an empty net means tcp
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| 		return newTCPListener(laddr)
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| 	default:
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| 		return nil, fmt.Errorf("unknown address type %s", net)
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| 	}
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| }
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| 
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| func newUnixListener(laddr string) (net.Listener, error) {
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| 	fi, err := os.Stat(laddr)
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| 	if err == nil {
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| 		// the file exists.
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| 		// try to remove it if it's a socket
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| 		if !isSocket(fi.Mode()) {
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| 			return nil, fmt.Errorf("file %s exists and is not a socket", laddr)
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| 		}
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| 
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| 		if err := os.Remove(laddr); err != nil {
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| 			return nil, err
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| 		}
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| 	} else if !os.IsNotExist(err) {
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| 		// we can't do stat on the file.
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| 		// it means we can not remove it
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| 		return nil, err
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| 	}
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| 
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| 	return net.Listen("unix", laddr)
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| }
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| 
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| func isSocket(m os.FileMode) bool {
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| 	return m&os.ModeSocket != 0
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| }
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| 
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| func newTCPListener(laddr string) (net.Listener, error) {
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| 	ln, err := net.Listen("tcp", laddr)
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| 	if err != nil {
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| 		return nil, err
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| 	}
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| 
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| 	return tcpKeepAliveListener{ln.(*net.TCPListener)}, nil
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| }
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