community
/
dns
3
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix datarace in Start/Shutdown 

Add mutex and guard a 'started' boolean as well as the stopUDP
and tcpTCP channels so that 'go test -race' does not trigger.

Closes #111, closes #114
This commit is contained in:
Miek Gieben 2014-08-30 10:34:44 +01:00
parent 06fc321c2c
commit ebc5489482
1 changed files with 24 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
server.go
View File

@ -231,10 +231,21 @@ type Server struct {
stopTCP chan bool
wgUDP sync.WaitGroup
wgTCP sync.WaitGroup
// make start/shutdown not racy
lock sync.Mutex
started bool
}
// ListenAndServe starts a nameserver on the configured address in *Server.
func (srv *Server) ListenAndServe() error {
srv.lock.Lock()
if srv.started {
return &Error{err: "server already started"}
}
srv.stopUDP, srv.stopTCP = make(chan bool), make(chan bool)
srv.started = true
srv.lock.Unlock()
addr := srv.Addr
if addr == "" {
addr = ":domain"
@ -244,7 +255,6 @@ func (srv *Server) ListenAndServe() error {
}
switch srv.Net {
case "tcp", "tcp4", "tcp6":
srv.stopTCP = make(chan bool)
a, e := net.ResolveTCPAddr(srv.Net, addr)
if e != nil {
return e
@ -255,7 +265,6 @@ func (srv *Server) ListenAndServe() error {
}
return srv.serveTCP(l)
case "udp", "udp4", "udp6":
srv.stopUDP = make(chan bool)
a, e := net.ResolveUDPAddr(srv.Net, addr)
if e != nil {
return e
@ -264,7 +273,6 @@ func (srv *Server) ListenAndServe() error {
if e != nil {
return e
}
if e := setUDPSocketOptions(l); e != nil {
return e
}
@ -276,11 +284,17 @@ func (srv *Server) ListenAndServe() error {
// ActivateAndServe starts a nameserver with the PacketConn or Listener
// configured in *Server. Its main use is to start a server from systemd.
func (srv *Server) ActivateAndServe() error {
srv.lock.Lock()
if srv.started {
return &Error{err: "server already started"}
}
srv.stopUDP, srv.stopTCP = make(chan bool), make(chan bool)
srv.started = true
srv.lock.Unlock()
if srv.UDPSize == 0 {
srv.UDPSize = MinMsgSize
}
if srv.PacketConn != nil {
srv.stopUDP = make(chan bool)
if srv.UDPSize == 0 {
srv.UDPSize = MinMsgSize
}
@ -292,7 +306,6 @@ func (srv *Server) ActivateAndServe() error {
}
}
if srv.Listener != nil {
srv.stopTCP = make(chan bool)
if t, ok := srv.Listener.(*net.TCPListener); ok {
return srv.serveTCP(t)
}
@ -305,6 +318,12 @@ func (srv *Server) ActivateAndServe() error {
// is taken down. If the Shutdown was not succesful an error is taking longer than reading
// timeout.
func (srv *Server) Shutdown() error {
srv.lock.Lock()
if !srv.started {
return &Error{err: "server not started"}
}
srv.started = false
srv.lock.Unlock()
net, addr := srv.Net, srv.Addr
switch {
case srv.Listener != nil: