media/formats/webm/webm_webvtt_parser.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 MEDIA_FORMATS_WEBM_WEBM_WEBVTT_PARSER_H_
   6 #define MEDIA_FORMATS_WEBM_WEBM_WEBVTT_PARSER_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "media/base/media_export.h"
  12
  13 namespace media {
  14
  15 class MEDIA_EXPORT WebMWebVTTParser {
  16  public:
  17   // Utility function to parse the WebVTT cue from a byte stream.
  18   static void Parse(const uint8* payload, int payload_size,
  19                     std::string* id,
  20                     std::string* settings,
  21                     std::string* content);
  22
  23  private:
  24   // The payload is the embedded WebVTT cue, stored in a WebM block.
  25   // The parser treats this as a UTF-8 byte stream.
  26   WebMWebVTTParser(const uint8* payload, int payload_size);
  27
  28   // Parse the cue identifier, settings, and content from the stream.
  29   void Parse(std::string* id, std::string* settings, std::string* content);
  30   // Remove a byte from the stream, advancing the stream pointer.
  31   // Returns true if a character was returned; false means "end of stream".
  32   bool GetByte(uint8* byte);
  33
  34   // Backup the stream pointer.
  35   void UngetByte();
  36
  37   // Parse a line of text from the stream.
  38   void ParseLine(std::string* line);
  39
  40   // Represents the portion of the stream that has not been consumed yet.
  41   const uint8* ptr_;
  42   const uint8* const ptr_end_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(WebMWebVTTParser);
  45 };
  46
  47 }  // namespace media
  48
  49 #endif  // MEDIA_FORMATS_WEBM_WEBM_WEBVTT_PARSER_H_