http: clarify use of w.conn.body in Write when sniffing.
R=gri, r, r, rsc
CC=golang-dev
https://golang.org/cl/4794047
diff --git a/src/pkg/http/server.go b/src/pkg/http/server.go
index f14ef8c..96547c4 100644
--- a/src/pkg/http/server.go
+++ b/src/pkg/http/server.go
@@ -359,8 +359,7 @@
w.needSniff = false
data := w.conn.body
- fmt.Fprintf(w.conn.buf, "Content-Type: %s\r\n", DetectContentType(data))
- io.WriteString(w.conn.buf, "\r\n")
+ fmt.Fprintf(w.conn.buf, "Content-Type: %s\r\n\r\n", DetectContentType(data))
if len(data) == 0 {
return
@@ -408,10 +407,14 @@
// We need to sniff the beginning of the output to
// determine the content type. Accumulate the
// initial writes in w.conn.body.
- body := w.conn.body
- m = copy(body[len(body):cap(body)], data)
- w.conn.body = body[:len(body)+m]
- if m == len(data) {
+ // Cap m so that append won't allocate.
+ m := cap(w.conn.body) - len(w.conn.body)
+ if m > len(data) {
+ m = len(data)
+ }
+ w.conn.body = append(w.conn.body, data[:m]...)
+ data = data[m:]
+ if len(data) == 0 {
// Copied everything into the buffer.
// Wait for next write.
return m, nil
@@ -423,7 +426,6 @@
// of the data as a normal Write.
// Calling sniff clears needSniff.
w.sniff()
- data = data[m:]
}
// TODO(rsc): if chunking happened after the buffering,
