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 FileDataSource::FileDataSource(base::File file)
  19     : force_read_errors_(false),
  20       force_streaming_(false) {
  21   if (!file_.Initialize(file.Pass()))
  22     return;
  23
  24   UpdateHostBytes();
  25 }
  26
  27 bool FileDataSource::Initialize(const base::FilePath& file_path) {
  28   DCHECK(!file_.IsValid());
  29
  30   if (!file_.Initialize(file_path))
  31     return false;
  32
  33   UpdateHostBytes();
  34   return true;
  35 }
  36
  37 void FileDataSource::set_host(DataSourceHost* host) {
  38   DataSource::set_host(host);
  39   UpdateHostBytes();
  40 }
  41
  42 void FileDataSource::Stop(const base::Closure& callback) {
  43   callback.Run();
  44 }
  45
  46 void FileDataSource::Read(int64 position, int size, uint8* data,
  47                           const DataSource::ReadCB& read_cb) {
  48   if (force_read_errors_ || !file_.IsValid()) {
  49     read_cb.Run(kReadError);
  50     return;
  51   }
  52
  53   int64 file_size = file_.length();
  54
  55   CHECK_GE(file_size, 0);
  56   CHECK_GE(position, 0);
  57   CHECK_GE(size, 0);
  58
  59   // Cap position and size within bounds.
  60   position = std::min(position, file_size);
  61   int64 clamped_size = std::min(static_cast<int64>(size), file_size - position);
  62
  63   memcpy(data, file_.data() + position, clamped_size);
  64   read_cb.Run(clamped_size);
  65 }
  66
  67 bool FileDataSource::GetSize(int64* size_out) {
  68   *size_out = file_.length();
  69   return true;
  70 }
  71
  72 bool FileDataSource::IsStreaming() {
  73   return force_streaming_;
  74 }
  75
  76 void FileDataSource::SetBitrate(int bitrate) {}
  77
  78 FileDataSource::~FileDataSource() {}
  79
  80 void FileDataSource::UpdateHostBytes() {
  81   if (host() && file_.IsValid()) {
  82     host()->SetTotalBytes(file_.length());
  83     host()->AddBufferedByteRange(0, file_.length());
  84   }
  85 }
  86
  87 }  // namespace media