Initial QSfera import

Server/vendor/github.com/crewjam/httperr/writer.go

@@ -0,0 +1,119 @@
+package httperr
+
+// Note: The writer proxies in this file are a heavily modified version of
+// code bearing the following message:
+//
+//   Copyright (c) 2014, 2015, 2016 Carl Jackson (carl@avtok.com)
+//
+//   MIT License
+//
+//   Permission is hereby granted, free of charge, to any person obtaining a copy of
+//   this software and associated documentation files (the "Software"), to deal in
+//   the Software without restriction, including without limitation the rights to
+//   use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+//   the Software, and to permit persons to whom the Software is furnished to do so,
+//   subject to the following conditions:
+//
+//   The above copyright notice and this permission notice shall be included in all
+//   copies or substantial portions of the Software.
+//
+//   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+//   FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+//   COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+//   IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+//   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import (
+	"bufio"
+	"bytes"
+	"io/ioutil"
+	"net"
+	"net/http"
+)
+
+// wrapWriter wraps an http.ResponseWriter, returning a proxy that
+// tracks the response.
+func wrapWriter(w http.ResponseWriter) (*basicWriter, http.ResponseWriter) {
+	_, isCloseNotifier := w.(http.CloseNotifier)
+	_, isFlusher := w.(http.Flusher)
+	_, isHijacker := w.(http.Hijacker)
+
+	bw := basicWriter{ResponseWriter: w}
+	if isCloseNotifier && isFlusher && isHijacker {
+		rv := fancyWriter{bw}
+		return &rv.basicWriter, &rv
+	}
+	if isFlusher {
+		rv := flushWriter{bw}
+		return &rv.basicWriter, &rv
+	}
+	return &bw, &bw
+}
+
+type basicWriter struct {
+	http.ResponseWriter
+
+	statusCode int
+	copy       *http.Response
+	body       *bytes.Buffer
+}
+
+func (b *basicWriter) WriteHeader(code int) {
+	b.statusCode = code
+	if code < 400 {
+		b.ResponseWriter.WriteHeader(code)
+		return
+	}
+
+	b.copy = &http.Response{
+		StatusCode: code,
+		Header:     b.ResponseWriter.Header(),
+	}
+}
+
+func (b *basicWriter) Write(buf []byte) (int, error) {
+	if b.copy == nil {
+		return b.ResponseWriter.Write(buf)
+	}
+
+	if b.body == nil {
+		b.body = &bytes.Buffer{}
+		b.copy.Body = ioutil.NopCloser(b.body)
+	}
+	return b.body.Write(buf)
+}
+
+type fancyWriter struct {
+	basicWriter
+}
+
+func (f *fancyWriter) CloseNotify() <-chan bool {
+	cn := f.basicWriter.ResponseWriter.(http.CloseNotifier)
+	return cn.CloseNotify()
+}
+
+func (f *fancyWriter) Flush() {
+	fl := f.basicWriter.ResponseWriter.(http.Flusher)
+	fl.Flush()
+}
+
+func (f *fancyWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	hj := f.basicWriter.ResponseWriter.(http.Hijacker)
+	return hj.Hijack()
+}
+
+var _ http.CloseNotifier = &fancyWriter{}
+var _ http.Flusher = &fancyWriter{}
+var _ http.Hijacker = &fancyWriter{}
+
+type flushWriter struct {
+	basicWriter
+}
+
+func (f *flushWriter) Flush() {
+	fl := f.basicWriter.ResponseWriter.(http.Flusher)
+	fl.Flush()
+}
+
+var _ http.Flusher = &flushWriter{}