Fixes header translation between SpdyHeaderBlock and other data structures. Not protected.

net/quic/spdy_utils.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/spdy_utils.h"
 
 #include <memory>
 #include <vector>
 
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
 #include "net/spdy/spdy_frame_builder.h"
 #include "net/spdy/spdy_framer.h"
 #include "net/spdy/spdy_protocol.h"
 #include "url/gurl.h"
 
 using base::StringPiece;
 using std::string;
 using std::vector;
 
 namespace net {
@@ skipping 94 matching lines @@
       DVLOG(1) << "Header name must not be empty.";
       return false;
     }
 
     if (std::any_of(name.begin(), name.end(), base::IsAsciiUpper<char>)) {
       DLOG(ERROR) << "Malformed header: Header name " << name
                   << " contains upper-case characters.";
       return false;
     }
 
-    if (headers->find(name) != headers->end()) {
-      DLOG(ERROR) << "Duplicate header '" << name << "' found.";
-      return false;
+    auto iter = headers->find(name);
+    if (iter == headers->end()) {
+      (*headers)[name] = p.second;
+    } else {
+      // This header had multiple values, so it must be reconstructed.
+      string value = base::StringPrintf(
+          "%s%c%s", iter->second.as_string().c_str(), '\0', p.second.c_str());
+      headers->ReplaceOrAppendHeader(name, value);
     }
-
-    (*headers)[name] = p.second;
   }
 
   if (ContainsKey(*headers, "content-length")) {
     // Check whether multiple values are consistent.
     StringPiece content_length_header = (*headers)["content-length"];
     vector<string> values =
         base::SplitString(content_length_header, base::StringPiece("\0", 1),
                           base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
     for (const string& value : values) {
       int new_value;
@@ skipping 95 matching lines @@
   return GURL(GetUrlFromHeaderBlock(headers)).host();
 }
 
 // static
 bool SpdyUtils::UrlIsValid(const SpdyHeaderBlock& headers) {
   string url(GetUrlFromHeaderBlock(headers));
   return url != "" && GURL(url).is_valid();
 }
 
 }  // namespace net