Add WebSocketError to indicate decoding failure reason

net/websockets/websocket_frame_parser.h

 // Copyright (c) 2012 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.
 
 #ifndef NET_WEBSOCKETS_WEBSOCKET_FRAME_PARSER_H_
 #define NET_WEBSOCKETS_WEBSOCKET_FRAME_PARSER_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "net/base/net_export.h"
+#include "net/websockets/websocket_errors.h"
 #include "net/websockets/websocket_frame.h"
 
 namespace net {
 
 // Parses WebSocket frames from byte stream.
 //
 // Specification of WebSocket frame format is available at
 // <http://tools.ietf.org/html/rfc6455#section-5>.
 
 class NET_EXPORT_PRIVATE WebSocketFrameParser {
  public:
   WebSocketFrameParser();
   ~WebSocketFrameParser();
 
   // Decodes the given byte stream and stores parsed WebSocket frames in
   // |frame_chunks|.
   //
   // If the parser encounters invalid payload length format, Decode() fails
   // and returns false. Once Decode() has failed, the parser refuses to decode
   // any more data and future invocations of Decode() will simply return false.
   //
   // Payload data of parsed WebSocket frames may be incomplete; see comments in
   // websocket_frame.h for more details.
   bool Decode(const char* data,
               size_t length,
               ScopedVector<WebSocketFrameChunk>* frame_chunks);
 
-  // Returns true if the parser has ever failed to decode a WebSocket frame.
-  // TODO(yutak): Provide human-readable description of failure.
-  bool failed() const { return failed_; }
+  // Returns WEB_SOCKET_OK if the parser has not failed to decode WebSocket
+  // frames. Otherwise returns WebSocketError which is defined in
+  // websocket_errors.h. We can convert net::WebSocketError to net::Error by
+  // using WebSocketErrorToNetError().
+  WebSocketError websocket_error() const { return websocket_error_; }
 
  private:
   // Tries to decode a frame header from |current_read_pos_|.
   // If successful, this function updates |current_read_pos_|,
   // |current_frame_header_|, and |masking_key_| (if available).
   // This function may set |failed_| to true if it observes a corrupt frame.
   // If there is not enough data in the remaining buffer to parse a frame
   // header, this function returns without doing anything.
   void DecodeFrameHeader();
 
@@ skipping 12 matching lines @@
   size_t current_read_pos_;
 
   // Frame header and masking key of the current frame.
   // |masking_key_| is filled with zeros if the current frame is not masked.
   scoped_ptr<WebSocketFrameHeader> current_frame_header_;
   char masking_key_[WebSocketFrameHeader::kMaskingKeyLength];
 
   // Amount of payload data read so far for the current frame.
   uint64 frame_offset_;
 
-  bool failed_;
+  WebSocketError websocket_error_;
 
   DISALLOW_COPY_AND_ASSIGN(WebSocketFrameParser);
 };
 
 }  // namespace net
 
 #endif  // NET_WEBSOCKETS_WEBSOCKET_FRAME_PARSER_H_