1 // Copyright (c) 2012 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_BASE_DATA_SOURCE_H_ 6 #define MEDIA_BASE_DATA_SOURCE_H_ 7 8 #include "base/callback.h" 9 #include "base/time/time.h" 10 #include "media/base/media_export.h" 11 12 namespace media { 13 14 class MEDIA_EXPORT DataSource { 15 public: 16 typedef base::Callback<void(int64, int64)> StatusCallback; 17 typedef base::Callback<void(int)> ReadCB; 18 static const int kReadError; 19 20 DataSource(); 21 virtual ~DataSource(); 22 23 // Reads |size| bytes from |position| into |data|. And when the read is done 24 // or failed, |read_cb| is called with the number of bytes read or 25 // kReadError in case of error. 26 virtual void Read(int64 position, int size, uint8* data, 27 const DataSource::ReadCB& read_cb) = 0; 28 29 // Stops the DataSource. Once this is called all future Read() calls will 30 // return an error. 31 virtual void Stop(const base::Closure& callback) = 0; 32 33 // Returns true and the file size, false if the file size could not be 34 // retrieved. 35 virtual bool GetSize(int64* size_out) = 0; 36 37 // Returns true if we are performing streaming. In this case seeking is 38 // not possible. 39 virtual bool IsStreaming() = 0; 40 41 // Notify the DataSource of the bitrate of the media. 42 // Values of |bitrate| <= 0 are invalid and should be ignored. 43 virtual void SetBitrate(int bitrate) = 0; 44 45 private: 46 DISALLOW_COPY_AND_ASSIGN(DataSource); 47 }; 48 49 } // namespace media 50 51 #endif // MEDIA_BASE_DATA_SOURCE_H_ 52