net/server/web_socket_encoder.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_SERVER_WEB_SOCKET_ENCODER_H_
   6 #define NET_SERVER_WEB_SOCKET_ENCODER_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/strings/string_piece.h"
  13 #include "net/server/web_socket.h"
  14 #include "net/websockets/websocket_deflater.h"
  15 #include "net/websockets/websocket_inflater.h"
  16
  17 namespace net {
  18
  19 class WebSocketEncoder {
  20  public:
  21   ~WebSocketEncoder();
  22
  23   static WebSocketEncoder* CreateServer(const std::string& request_extensions,
  24                                         std::string* response_extensions);
  25
  26   static const char kClientExtensions[];
  27   static WebSocketEncoder* CreateClient(const std::string& response_extensions);
  28
  29   WebSocket::ParseResult DecodeFrame(const base::StringPiece& frame,
  30                                      int* bytes_consumed,
  31                                      std::string* output);
  32
  33   void EncodeFrame(const std::string& frame,
  34                    int masking_key,
  35                    std::string* output);
  36
  37  private:
  38   explicit WebSocketEncoder(bool is_server);
  39   WebSocketEncoder(bool is_server,
  40                    int deflate_bits,
  41                    int inflate_bits,
  42                    bool no_context_takeover);
  43
  44   // Parses a value in the Sec-WebSocket-Extensions header. If it contains a
  45   // single element of the permessage-deflate extension, stores the result of
  46   // parsing the parameters of the extension into the given variables.
  47   // Otherwise, returns with *deflate set to false.
  48   //
  49   // - If the client_max_window_bits parameter is missing, *client_window_bits
  50   //   defaults to 15.
  51   // - If the client_max_window_bits parameter has an invalid value,
  52   //   *client_window_bits will be set to 0.
  53   // - If the server_max_window_bits parameter is missing, *server_window_bits
  54   //   defaults to 15.
  55   // - If the server_max_window_bits parameter has an invalid value,
  56   //   *client_window_bits will be set to 0.
  57   //
  58   // TODO(tyoshino): Consider using a struct than taking a lot of pointers for
  59   // output.
  60   static void ParseExtensions(const std::string& header_value,
  61                               bool* deflate,
  62                               bool* has_client_window_bits,
  63                               int* client_window_bits,
  64                               int* server_window_bits,
  65                               bool* client_no_context_takeover,
  66                               bool* server_no_context_takeover);
  67
  68   bool Inflate(std::string* message);
  69   bool Deflate(const std::string& message, std::string* output);
  70
  71   scoped_ptr<WebSocketDeflater> deflater_;
  72   scoped_ptr<WebSocketInflater> inflater_;
  73   bool is_server_;
  74
  75   DISALLOW_COPY_AND_ASSIGN(WebSocketEncoder);
  76 };
  77
  78 }  // namespace net
  79
  80 #endif  // NET_SERVER_WEB_SOCKET_ENCODER_H_