diff options
| -rw-r--r-- | caddy.go | 2 | ||||
| -rw-r--r-- | listeners.go | 68 | ||||
| -rw-r--r-- | modules/caddyhttp/responsewriter.go | 3 |
3 files changed, 65 insertions, 8 deletions
@@ -34,7 +34,7 @@ func Start(cfg Config) error { currentCfgMu.Lock() if currentCfg != nil { - for _, r := range cfg.runners { + for _, r := range currentCfg.runners { err := r.Cancel() if err != nil { log.Println(err) diff --git a/listeners.go b/listeners.go index a3efc9e..6849319 100644 --- a/listeners.go +++ b/listeners.go @@ -5,6 +5,7 @@ import ( "net" "sync" "sync/atomic" + "time" ) // Listen returns a listener suitable for use in a Caddy module. @@ -41,16 +42,58 @@ type fakeCloseListener struct { // Accept accepts connections until Close() is called. func (fcl *fakeCloseListener) Accept() (net.Conn, error) { + // if the listener is already "closed", return error if atomic.LoadInt32(&fcl.closed) == 1 { - return nil, ErrSwappingServers + return nil, fcl.fakeClosedErr() } - return fcl.Listener.Accept() + + // wrap underlying accept + conn, err := fcl.Listener.Accept() + if err == nil { + return conn, nil + } + + if atomic.LoadInt32(&fcl.closed) == 1 { + // clear the deadline + switch ln := fcl.Listener.(type) { + case *net.TCPListener: + ln.SetDeadline(time.Time{}) + case *net.UnixListener: + ln.SetDeadline(time.Time{}) + } + + // if we cancelled the Accept() by setting a deadline + // on the listener, we need to make sure any callers of + // Accept() think the listener was actually closed; + // if we return the timeout error instead, callers might + // simply retry, leaking goroutines for longer + if netErr, ok := err.(net.Error); ok && netErr.Timeout() { + return nil, fcl.fakeClosedErr() + } + } + + return nil, err } // Close stops accepting new connections, but does not // actually close the underlying listener. func (fcl *fakeCloseListener) Close() error { - atomic.StoreInt32(&fcl.closed, 1) + if atomic.CompareAndSwapInt32(&fcl.closed, 0, 1) { + // unfortunately, there is no way to cancel any + // currently-blocking calls to Accept() that are + // awaiting connections since we're not actually + // closing the listener; so we cheat by setting + // a deadline in the past, which forces it to + // time out; note that this only works for + // certain types of listeners... + switch ln := fcl.Listener.(type) { + case *net.TCPListener: + ln.SetDeadline(time.Now().Add(-1 * time.Minute)) + case *net.UnixListener: + ln.SetDeadline(time.Now().Add(-1 * time.Minute)) + } + } + return nil } @@ -59,10 +102,21 @@ func (fcl *fakeCloseListener) CloseUnderlying() error { return fcl.Listener.Close() } -// ErrSwappingServers is returned by fakeCloseListener when -// Close() is called, indicating that it is pretending to -// be closed so that the server using it can terminate. -var ErrSwappingServers = fmt.Errorf("listener 'closed' 😉") +func (fcl *fakeCloseListener) fakeClosedErr() error { + return &net.OpError{ + Op: "accept", + Net: fcl.Listener.Addr().Network(), + Addr: fcl.Listener.Addr(), + Err: ErrFakeClosed, + } +} + +// ErrFakeClosed is the underlying error value returned by +// fakeCloseListener.Accept() after Close() has been called, +// indicating that it is pretending to be closed so that the +// server using it can terminate, while the underlying +// socket is actually left open. +var ErrFakeClosed = fmt.Errorf("listener 'closed' 😉") var ( listeners = make(map[string]net.Listener) diff --git a/modules/caddyhttp/responsewriter.go b/modules/caddyhttp/responsewriter.go index 587d9f9..8aefd3f 100644 --- a/modules/caddyhttp/responsewriter.go +++ b/modules/caddyhttp/responsewriter.go @@ -7,6 +7,9 @@ import ( "net/http" ) +// TODO: Is this type really required? Wouldn't embedding the +// default ResponseWriter always work too, when wrapping it? + // ResponseWriterWrapper wraps an underlying ResponseWriter and // promotes its Pusher/Flusher/CloseNotifier/Hijacker methods // as well. To use this type, embed a pointer to it within your |