chrome/browser/chromeos/file_system_provider/fileapi/backend_delegate.cc

   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 #include "chrome/browser/chromeos/file_system_provider/fileapi/backend_delegate.h"
   6
   7 #include "base/memory/scoped_ptr.h"
   8 #include "chrome/browser/chromeos/file_system_provider/fileapi/buffering_file_stream_reader.h"
   9 #include "chrome/browser/chromeos/file_system_provider/fileapi/buffering_file_stream_writer.h"
  10 #include "chrome/browser/chromeos/file_system_provider/fileapi/file_stream_reader.h"
  11 #include "chrome/browser/chromeos/file_system_provider/fileapi/file_stream_writer.h"
  12 #include "chrome/browser/chromeos/file_system_provider/fileapi/provider_async_file_util.h"
  13 #include "chrome/browser/chromeos/file_system_provider/fileapi/watcher_manager.h"
  14 #include "content/public/browser/browser_thread.h"
  15 #include "storage/browser/fileapi/file_stream_reader.h"
  16 #include "storage/browser/fileapi/file_stream_writer.h"
  17 #include "storage/browser/fileapi/file_system_url.h"
  18
  19 using content::BrowserThread;
  20
  21 namespace chromeos {
  22 namespace file_system_provider {
  23 namespace {
  24
  25 // Size of the stream reader internal buffer. At most this number of bytes will
  26 // be read ahead of the requested data.
  27 const int kReaderBufferSize = 512 * 1024;  // 512KB.
  28
  29 // Size of the stream writer internal buffer. At most this number of bytes will
  30 // be postponed for writing.
  31 const int kWriterBufferSize = 512 * 1024;  // 512KB.
  32
  33 }  // namespace
  34
  35 BackendDelegate::BackendDelegate()
  36     : async_file_util_(new internal::ProviderAsyncFileUtil),
  37       watcher_manager_(new WatcherManager) {
  38 }
  39
  40 BackendDelegate::~BackendDelegate() {}
  41
  42 storage::AsyncFileUtil* BackendDelegate::GetAsyncFileUtil(
  43     storage::FileSystemType type) {
  44   DCHECK_CURRENTLY_ON(BrowserThread::IO);
  45   DCHECK_EQ(storage::kFileSystemTypeProvided, type);
  46   return async_file_util_.get();
  47 }
  48
  49 scoped_ptr<storage::FileStreamReader> BackendDelegate::CreateFileStreamReader(
  50     const storage::FileSystemURL& url,
  51     int64 offset,
  52     int64 max_bytes_to_read,
  53     const base::Time& expected_modification_time,
  54     storage::FileSystemContext* context) {
  55   DCHECK_CURRENTLY_ON(BrowserThread::IO);
  56   DCHECK_EQ(storage::kFileSystemTypeProvided, url.type());
  57
  58   return scoped_ptr<storage::FileStreamReader>(new BufferingFileStreamReader(
  59       scoped_ptr<storage::FileStreamReader>(new FileStreamReader(
  60           context, url, offset, expected_modification_time)),
  61       kReaderBufferSize,
  62       max_bytes_to_read));
  63 }
  64
  65 scoped_ptr<storage::FileStreamWriter> BackendDelegate::CreateFileStreamWriter(
  66     const storage::FileSystemURL& url,
  67     int64 offset,
  68     storage::FileSystemContext* context) {
  69   DCHECK_CURRENTLY_ON(BrowserThread::IO);
  70   DCHECK_EQ(storage::kFileSystemTypeProvided, url.type());
  71
  72   return scoped_ptr<storage::FileStreamWriter>(new BufferingFileStreamWriter(
  73       scoped_ptr<storage::FileStreamWriter>(new FileStreamWriter(url, offset)),
  74       kWriterBufferSize));
  75 }
  76
  77 storage::WatcherManager* BackendDelegate::GetWatcherManager(
  78     storage::FileSystemType type) {
  79   DCHECK_CURRENTLY_ON(BrowserThread::UI);
  80   DCHECK_EQ(storage::kFileSystemTypeProvided, type);
  81   return watcher_manager_.get();
  82 }
  83
  84 void BackendDelegate::GetRedirectURLForContents(
  85     const storage::FileSystemURL& url,
  86     const storage::URLCallback& callback) {
  87   DCHECK_CURRENTLY_ON(BrowserThread::IO);
  88   DCHECK_EQ(storage::kFileSystemTypeProvided, url.type());
  89   callback.Run(GURL());
  90 }
  91
  92 }  // namespace file_system_provider
  93 }  // namespace chromeos