Media Source dispatches inband text tracks

media/webm/webm_webvtt_parser.h

+// 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.
+
+#ifndef MEDIA_WEBM_WEBM_WEBVTT_PARSER_H_
+#define MEDIA_WEBM_WEBM_WEBVTT_PARSER_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+class MEDIA_EXPORT WebMWebVTTParser {
+ public:
+  // Utility function to parse the WebVTT cue from a byte stream.
+  static void Parse(const uint8* payload, int payload_size,
+                    std::string* id,
+                    std::string* settings,
+                    std::string* content);
+
+ private:
+  // The payload is the embedded WebVTT cue, stored in a WebM block.
+  // The parser treats this as a UTF-8 byte stream.
+  WebMWebVTTParser(const uint8* payload, int payload_size);
+
+  // Parse the cue identifier, settings, and content from the stream.
+  void Parse(std::string* id, std::string* settings, std::string* content);
+  // Remove a byte from the stream, advancing the stream pointer.
+  // Returns true if a character was returned; false means "end of stream".
+  bool GetByte(uint8* byte);
+
+  // Backup the stream pointer.
+  void UngetByte();
+
+  // Parse a line of text from the stream.
+  void ParseLine(std::string* line);
+
+  // Represents the portion of the stream that has not been consumed yet.
+  const uint8* ptr_;
+  const uint8* const ptr_end_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebMWebVTTParser);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_WEBM_WEBM_WEBVTT_PARSER_H_