net/http: document that conn.Hijack might have left-over read/write timeouts on net.Conn #8296
Description
What does 'go version' print? Found with go-1.2rc3, present in go-1.3, and still present in the default branch as of 20272:90616fa61ef4. What steps reproduce the problem? Setting a ReadTimeout or WriteTimeout on an http.Server and then hijacking a http.conn (passed as the ResponseWriter) from a request handler leaves the deadlines set on the connection. This causes unexpected read and write behavior, requiring an unnatural removal of the deadlines after hijacking. I found this while implementing the server half of the HTML5 EventSource API, and it also affects any other hijack users (e.g. go.net's websocket package does not have code to clear deadlines when it takes over a connection; I have not tested it though.) A simplified example of the issue is here (probably useful to derive a regression test from): http://play.golang.org/p/bRyjSayMJN Adding these two lines fixes the issue: diff -r 90616fa61ef4 src/pkg/net/http/server.go --- a/src/pkg/net/http/server.go Fri Jun 27 18:30:09 2014 -0700 +++ b/src/pkg/net/http/server.go Fri Jun 27 22:43:18 2014 -0700 @@ -128,18 +128,20 @@ func (c *conn) hijack() (rwc net.Conn, buf *bufio.ReadWriter, err error) { c.mu.Lock() defer c.mu.Unlock() if c.hijackedv { return nil, nil, ErrHijacked } if c.closeNotifyc != nil { return nil, nil, errors.New("http: Hijack is incompatible with use of CloseNotifier") } + c.rwc.SetReadDeadline(time.Time{}) + c.rwc.SetWriteDeadline(time.Time{}) c.hijackedv = true rwc = c.rwc buf = c.buf c.rwc = nil c.buf = nil c.setState(rwc, StateHijacked) return }