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Fix the documentation of the responder package

This commit is contained in:
Miek Gieben 2011-01-13 16:52:12 +01:00
parent ea275e888e
commit 53bea506ba
1 changed files with 28 additions and 27 deletions
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55
responder/responder.go
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@ -2,10 +2,9 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// DNS server
// DNS server implementation
// For every reply the resolver answers by sending the
// received packet (with a possible error) back on the channel.
// Package responder implements a DNS server
package responder
import (
@ -15,33 +14,35 @@ import (
)
type Server struct {
Address string // interface to use, for multiple interfaces, use multiple servers
Port string // what port to use
Timeout int // seconds before giving up on packet
Tcp bool // use TCP
Mangle func([]byte) []byte // mangle the packet, before sending
Address string // interface to use, for multiple interfaces, use multiple servers
Port string // what port to use
Timeout int // seconds before giving up on packet
Tcp bool // use TCP
}
type Msg struct {
cu *net.UDPConn // udp conn
ct *net.TCPConn // tcp conn
type msg struct {
cu *net.UDPConn // udp conn
ct *net.TCPConn // tcp conn
addr net.Addr // remote address
msg []byte // raw dns message
err os.Error // any errors
}
// Every nameserver must implement the Handler interface.
// Every nameserver implements the Responder interface. It defines
// the kind of nameserver
type Responder interface {
// Receives the raw message content
// Receives the raw message content and writes back
// an udp response. An UDP connection needs a remote
// address to write to.
ResponderUDP(c *net.UDPConn, a net.Addr, in []byte)
// Receives the raw message content
// Receives the raw message content and writes back
// a tcp response. A TCP connection does need to
// know explicitly be told the remote address.
ResponderTCP(c *net.TCPConn, in []byte)
}
// This is a NAMESERVER
// Stop it by sending it true over the channel
// NewResponder returns a channel, for communication (start/stop)
// caN we use the channel for other stuff??
// Start a new responder. The returned channel is only used
// to stop the responder.
func (res *Server) NewResponder(h Responder, ch chan bool) os.Error {
var port string
if len(res.Address) == 0 {
@ -55,7 +56,7 @@ func (res *Server) NewResponder(h Responder, ch chan bool) os.Error {
}
switch res.Tcp {
case true:
tch := make(chan Msg)
tch := make(chan msg)
a, _ := net.ResolveTCPAddr(res.Address + ":" + port)
go listenerTCP(a, tch)
foreverTCP:
@ -74,7 +75,7 @@ func (res *Server) NewResponder(h Responder, ch chan bool) os.Error {
}
case false:
uch := make(chan Msg)
uch := make(chan msg)
a, _ := net.ResolveUDPAddr(res.Address + ":" + port)
go listenerUDP(a, uch)
foreverUDP:
@ -94,7 +95,7 @@ func (res *Server) NewResponder(h Responder, ch chan bool) os.Error {
return nil
}
func listenerUDP(a *net.UDPAddr, ch chan Msg) {
func listenerUDP(a *net.UDPAddr, ch chan msg) {
c, _ := net.ListenUDP("udp", a)
// check error TODO(mg)
for {
@ -105,11 +106,11 @@ func listenerUDP(a *net.UDPAddr, ch chan Msg) {
}
m = m[:n]
// if closed(ch) c.Close() TODO(mg)
ch <- Msg{cu: c, addr: radd, msg: m}
ch <- msg{cu: c, addr: radd, msg: m}
}
}
func listenerTCP(a *net.TCPAddr, ch chan Msg) {
func listenerTCP(a *net.TCPAddr, ch chan msg) {
t, _ := net.ListenTCP("tcp", a)
for {
l := make([]byte, 2) // receiver length
@ -142,11 +143,11 @@ func listenerTCP(a *net.TCPAddr, ch chan Msg) {
}
i += n
}
ch <- Msg{ct: c, msg: m}
ch <- msg{ct: c, msg: m}
}
}
// Send a raw msg over a TCP connection
// Send a buffer on the TCP connection
func SendTCP(m []byte, c *net.TCPConn) os.Error {
l := make([]byte, 2)
l[0] = byte(len(m) >> 8)
@ -164,8 +165,8 @@ func SendTCP(m []byte, c *net.TCPConn) os.Error {
return nil
}
// if we do tcp we should also provide an udp version
// First the message TODO(mg)
// Small helper function to help sending UDP packets. Mostly
// done for the symmetry. see SendTCP.
func SendUDP(m []byte, c *net.UDPConn, a net.Addr) os.Error {
_, err := c.WriteTo(m, a)
if err != nil {