[dev.fuzz] all: merge master into dev.fuzz

Change-Id: I5d8c8329ccc9d747bd81ade6b1cb7cb8ae2e94b2

1 files changed, 26 insertions, 13 deletions

diff --git a/src/net/http/cgi/child.go b/src/net/http/cgi/child.go
index d7d813e68a..0114da377b 100644
--- a/src/net/http/cgi/child.go
+++ b/src/net/http/cgi/child.go
@@ -13,7 +13,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
@@ -32,7 +31,7 @@ func Request() (*http.Request, error) {
 		return nil, err
 	}
 	if r.ContentLength > 0 {
-		r.Body = ioutil.NopCloser(io.LimitReader(os.Stdin, r.ContentLength))
+		r.Body = io.NopCloser(io.LimitReader(os.Stdin, r.ContentLength))
 	}
 	return r, nil
 }
@@ -166,10 +165,12 @@ func Serve(handler http.Handler) error {
 }
 
 type response struct {
-	req        *http.Request
-	header     http.Header
-	bufw       *bufio.Writer
-	headerSent bool
+	req            *http.Request
+	header         http.Header
+	code           int
+	wroteHeader    bool
+	wroteCGIHeader bool
+	bufw           *bufio.Writer
 }
 
 func (r *response) Flush() {
@@ -181,26 +182,38 @@ func (r *response) Header() http.Header {
 }
 
 func (r *response) Write(p []byte) (n int, err error) {
-	if !r.headerSent {
+	if !r.wroteHeader {
 		r.WriteHeader(http.StatusOK)
 	}
+	if !r.wroteCGIHeader {
+		r.writeCGIHeader(p)
+	}
 	return r.bufw.Write(p)
 }
 
 func (r *response) WriteHeader(code int) {
-	if r.headerSent {
+	if r.wroteHeader {
 		// Note: explicitly using Stderr, as Stdout is our HTTP output.
 		fmt.Fprintf(os.Stderr, "CGI attempted to write header twice on request for %s", r.req.URL)
 		return
 	}
-	r.headerSent = true
-	fmt.Fprintf(r.bufw, "Status: %d %s\r\n", code, http.StatusText(code))
+	r.wroteHeader = true
+	r.code = code
+}
 
-	// Set a default Content-Type
+// writeCGIHeader finalizes the header sent to the client and writes it to the output.
+// p is not written by writeHeader, but is the first chunk of the body
+// that will be written. It is sniffed for a Content-Type if none is
+// set explicitly.
+func (r *response) writeCGIHeader(p []byte) {
+	if r.wroteCGIHeader {
+		return
+	}
+	r.wroteCGIHeader = true
+	fmt.Fprintf(r.bufw, "Status: %d %s\r\n", r.code, http.StatusText(r.code))
 	if _, hasType := r.header["Content-Type"]; !hasType {
-		r.header.Add("Content-Type", "text/html; charset=utf-8")
+		r.header.Set("Content-Type", http.DetectContentType(p))
 	}
-
 	r.header.Write(r.bufw)
 	r.bufw.WriteString("\r\n")
 	r.bufw.Flush()