[WebSocket] Fix permessage-deflate handshake failure messages.

net/websockets/websocket_basic_handshake_stream.cc

 // Copyright 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/websockets/websocket_basic_handshake_stream.h"
 
 #include <algorithm>
 #include <iterator>
 #include <set>
 #include <string>
@@ skipping 224 matching lines @@
   typedef std::vector<WebSocketExtension::Parameter> ParameterVector;
 
   DCHECK_EQ("permessage-deflate", extension.name());
   const ParameterVector& parameters = extension.parameters();
   std::set<std::string> seen_names;
   for (ParameterVector::const_iterator it = parameters.begin();
        it != parameters.end(); ++it) {
     const std::string& name = it->name();
     if (seen_names.count(name) != 0) {
       *failure_message =
-          "Received duplicate permessage-deflate extension parameter " + name;
+          "Error in permessage-deflate: "

[Adam Rice, 2014/02/10 10:16:14]

There are enough of these that it is probably worth having a little function to
add the prefix and return false, so you can just do

return FormatDeflateError(failure_message, "Received duplicate
permessage-deflate extension parameter " + name);

or similar.

[yhirano, 2014/02/10 12:17:33]

Done.

+          "Received duplicate permessage-deflate extension parameter " +
+          name;
       return false;
     }
     seen_names.insert(name);
     const std::string client_or_server(name, 0, kPrefixLen);
     const bool is_client = (client_or_server == kClientPrefix);
     if (!is_client && client_or_server != kServerPrefix) {
       *failure_message =
+          "Error in permessage-deflate: "
           "Received an unexpected permessage-deflate extension parameter";
       return false;
     }
     const std::string rest(name, kPrefixLen);
     if (rest == kNoContextTakeover) {
       if (it->HasValue()) {
-        *failure_message = "Received invalid " + name + " parameter";
+        *failure_message = "Error in permessage-deflate: Received invalid " +
+                           name + " parameter";
         return false;
       }
       if (is_client)
         params->deflate_mode = WebSocketDeflater::DO_NOT_TAKE_OVER_CONTEXT;
     } else if (rest == kMaxWindowBits) {
       if (!it->HasValue()) {
-        *failure_message = name + " must have value";
+        *failure_message =
+            "Error in permessage-deflate: " + name + " must have value";
         return false;
       }
       int bits = 0;
       if (!base::StringToInt(it->value(), &bits) || bits < 8 || bits > 15 ||
           it->value()[0] == '0' ||
           it->value().find_first_not_of("0123456789") != std::string::npos) {
-        *failure_message = "Received invalid " + name + " parameter";
+        *failure_message = "Error in permessage-deflate: Received invalid " +
+                           name + " parameter";
         return false;
       }
       if (is_client)
         params->client_window_bits = bits;
     } else {
       *failure_message =
+          "Error in permessage-deflate: "
           "Received an unexpected permessage-deflate extension parameter";
       return false;
     }
   }
   params->deflate_enabled = true;
   return true;
 }
 
 bool ValidateExtensions(const HttpResponseHeaders* headers,
                         const std::vector<std::string>& requested_extensions,
@@ skipping 306 matching lines @@
                          &extensions_,
                          &failure_message_,
                          extension_params_.get())) {
     return OK;
   }
   failure_message_ = "Error during WebSocket handshake: " + failure_message_;
   return ERR_INVALID_RESPONSE;
 }
 
 }  // namespace net