media/filters/file_data_source.cc

   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 #include "media/filters/file_data_source.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/logging.h"
  10
  11 namespace media {
  12
  13 FileDataSource::FileDataSource()
  14     : force_read_errors_(false),
  15       force_streaming_(false) {
  16 }
  17
  18 bool FileDataSource::Initialize(const base::FilePath& file_path) {
  19   DCHECK(!file_.IsValid());
  20
  21   if (!file_.Initialize(file_path))
  22     return false;
  23
  24   UpdateHostBytes();
  25   return true;
  26 }
  27
  28 void FileDataSource::set_host(DataSourceHost* host) {
  29   DataSource::set_host(host);
  30   UpdateHostBytes();
  31 }
  32
  33 void FileDataSource::Stop(const base::Closure& callback) {
  34   callback.Run();
  35 }
  36
  37 void FileDataSource::Read(int64 position, int size, uint8* data,
  38                           const DataSource::ReadCB& read_cb) {
  39   if (force_read_errors_ || !file_.IsValid()) {
  40     read_cb.Run(kReadError);
  41     return;
  42   }
  43
  44   int64 file_size = file_.length();
  45
  46   CHECK_GE(file_size, 0);
  47   CHECK_GE(position, 0);
  48   CHECK_GE(size, 0);
  49
  50   // Cap position and size within bounds.
  51   position = std::min(position, file_size);
  52   int64 clamped_size = std::min(static_cast<int64>(size), file_size - position);
  53
  54   memcpy(data, file_.data() + position, clamped_size);
  55   read_cb.Run(clamped_size);
  56 }
  57
  58 bool FileDataSource::GetSize(int64* size_out) {
  59   *size_out = file_.length();
  60   return true;
  61 }
  62
  63 bool FileDataSource::IsStreaming() {
  64   return force_streaming_;
  65 }
  66
  67 void FileDataSource::SetBitrate(int bitrate) {}
  68
  69 FileDataSource::~FileDataSource() {}
  70
  71 void FileDataSource::UpdateHostBytes() {
  72   if (host() && file_.IsValid()) {
  73     host()->SetTotalBytes(file_.length());
  74     host()->AddBufferedByteRange(0, file_.length());
  75   }
  76 }
  77
  78 }  // namespace media