Add WebSocketError to indicate decoding failure reason

net/websockets/websocket_frame_parser.cc

Index: net/websockets/websocket_frame_parser.cc
diff --git a/net/websockets/websocket_frame_parser.cc b/net/websockets/websocket_frame_parser.cc
index edbd0e6fc82bf3baaa88662372474e1929cb107c..af6ca3e53475081582257446df00ec3c40e14942 100644
--- a/net/websockets/websocket_frame_parser.cc
+++ b/net/websockets/websocket_frame_parser.cc
@@ -36,7 +36,7 @@ namespace net {
 WebSocketFrameParser::WebSocketFrameParser()
     : current_read_pos_(0),
       frame_offset_(0),
-      failed_(false) {
+      websocket_error_(WEB_SOCKET_OK) {
   std::fill(masking_key_,
             masking_key_ + WebSocketFrameHeader::kMaskingKeyLength,
             '\0');
@@ -49,7 +49,7 @@ bool WebSocketFrameParser::Decode(
     const char* data,
     size_t length,
     ScopedVector<WebSocketFrameChunk>* frame_chunks) {
-  if (failed_)
+  if (websocket_error_ != WEB_SOCKET_OK)
     return false;
   if (!length)
     return true;
@@ -61,7 +61,7 @@ bool WebSocketFrameParser::Decode(
     bool first_chunk = false;
     if (!current_frame_header_.get()) {
       DecodeFrameHeader();
-      if (failed_)
+      if (websocket_error_ != WEB_SOCKET_OK)
         return false;
       // If frame header is incomplete, then carry over the remaining
       // data to the next round of Decode().
@@ -121,8 +121,6 @@ void WebSocketFrameParser::DecodeFrameHeader() {
 
   bool masked = (second_byte & kMaskBit) != 0;
   uint64 payload_length = second_byte & kPayloadLengthMask;
-  bool valid_length_format = true;
-  bool message_too_big = false;
   if (payload_length == kPayloadLengthWithTwoByteExtendedLengthField) {
     if (end - current < 2)
       return;
@@ -131,21 +129,19 @@ void WebSocketFrameParser::DecodeFrameHeader() {
     current += 2;
     payload_length = payload_length_16;
     if (payload_length <= kMaxPayloadLengthWithoutExtendedLengthField)
-      valid_length_format = false;
+      websocket_error_ = WEB_SOCKET_ERR_PROTOCOL_ERROR;
   } else if (payload_length == kPayloadLengthWithEightByteExtendedLengthField) {
     if (end - current < 8)
       return;
     ReadBigEndian(current, &payload_length);
     current += 8;
     if (payload_length <= kuint16max ||
-        payload_length > static_cast<uint64>(kint64max)) {
-      valid_length_format = false;
-    }
-    if (payload_length > static_cast<uint64>(kint32max))
-      message_too_big = true;
+        payload_length > static_cast<uint64>(kint64max))
+      websocket_error_ = WEB_SOCKET_ERR_PROTOCOL_ERROR;

[mmenke, 2012/08/02 14:08:22]

nit:  Need brackets here, since the condition takes up two lines.

[Takashi Toyoshima, 2012/08/03 05:53:14]

Done.

+    else if (payload_length > static_cast<uint64>(kint32max))
+      websocket_error_ = WEB_SOCKET_ERR_MESSAGE_TOO_BIG;
   }
-  if (!valid_length_format || message_too_big) {
-    failed_ = true;
+  if (websocket_error_ != WEB_SOCKET_OK) {
     buffer_.clear();
     current_read_pos_ = 0;
     current_frame_header_.reset();