src/webkit/browser/fileapi/sandbox_file_system_backend_delegate.cc

   1 // Copyright 2013 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 "webkit/browser/fileapi/sandbox_file_system_backend_delegate.h"
   6
   7 #include "base/command_line.h"
   8 #include "base/file_util.h"
   9 #include "base/metrics/histogram.h"
  10 #include "base/stl_util.h"
  11 #include "base/task_runner_util.h"
  12 #include "net/base/net_util.h"
  13 #include "webkit/browser/blob/file_stream_reader.h"
  14 #include "webkit/browser/fileapi/async_file_util_adapter.h"
  15 #include "webkit/browser/fileapi/file_system_context.h"
  16 #include "webkit/browser/fileapi/file_system_operation_context.h"
  17 #include "webkit/browser/fileapi/file_system_url.h"
  18 #include "webkit/browser/fileapi/file_system_usage_cache.h"
  19 #include "webkit/browser/fileapi/obfuscated_file_util.h"
  20 #include "webkit/browser/fileapi/sandbox_file_stream_writer.h"
  21 #include "webkit/browser/fileapi/sandbox_file_system_backend.h"
  22 #include "webkit/browser/fileapi/sandbox_quota_observer.h"
  23 #include "webkit/browser/quota/quota_manager.h"
  24 #include "webkit/common/fileapi/file_system_util.h"
  25
  26 namespace fileapi {
  27
  28 namespace {
  29
  30 const char kTemporaryOriginsCountLabel[] = "FileSystem.TemporaryOriginsCount";
  31 const char kPersistentOriginsCountLabel[] = "FileSystem.PersistentOriginsCount";
  32
  33 const char kOpenFileSystemLabel[] = "FileSystem.OpenFileSystem";
  34 const char kOpenFileSystemDetailLabel[] = "FileSystem.OpenFileSystemDetail";
  35 const char kOpenFileSystemDetailNonThrottledLabel[] =
  36     "FileSystem.OpenFileSystemDetailNonthrottled";
  37 int64 kMinimumStatsCollectionIntervalHours = 1;
  38
  39 // For type directory names in ObfuscatedFileUtil.
  40 // TODO(kinuko,nhiroki): Each type string registration should be done
  41 // via its own backend.
  42 const char kTemporaryDirectoryName[] = "t";
  43 const char kPersistentDirectoryName[] = "p";
  44 const char kSyncableDirectoryName[] = "s";
  45
  46 const char* kPrepopulateTypes[] = {
  47   kPersistentDirectoryName,
  48   kTemporaryDirectoryName
  49 };
  50
  51 enum FileSystemError {
  52   kOK = 0,
  53   kIncognito,
  54   kInvalidSchemeError,
  55   kCreateDirectoryError,
  56   kNotFound,
  57   kUnknownError,
  58   kFileSystemErrorMax,
  59 };
  60
  61 // Restricted names.
  62 // http://dev.w3.org/2009/dap/file-system/file-dir-sys.html#naming-restrictions
  63 const base::FilePath::CharType* const kRestrictedNames[] = {
  64   FILE_PATH_LITERAL("."), FILE_PATH_LITERAL(".."),
  65 };
  66
  67 // Restricted chars.
  68 const base::FilePath::CharType kRestrictedChars[] = {
  69   FILE_PATH_LITERAL('/'), FILE_PATH_LITERAL('\\'),
  70 };
  71
  72 std::string GetTypeStringForURL(const FileSystemURL& url) {
  73   return SandboxFileSystemBackendDelegate::GetTypeString(url.type());
  74 }
  75
  76 std::set<std::string> GetKnownTypeStrings() {
  77   std::set<std::string> known_type_strings;
  78   known_type_strings.insert(kTemporaryDirectoryName);
  79   known_type_strings.insert(kPersistentDirectoryName);
  80   known_type_strings.insert(kSyncableDirectoryName);
  81   return known_type_strings;
  82 }
  83
  84 class ObfuscatedOriginEnumerator
  85     : public SandboxFileSystemBackendDelegate::OriginEnumerator {
  86  public:
  87   explicit ObfuscatedOriginEnumerator(ObfuscatedFileUtil* file_util) {
  88     enum_.reset(file_util->CreateOriginEnumerator());
  89   }
  90   virtual ~ObfuscatedOriginEnumerator() {}
  91
  92   virtual GURL Next() OVERRIDE {
  93     return enum_->Next();
  94   }
  95
  96   virtual bool HasFileSystemType(FileSystemType type) const OVERRIDE {
  97     return enum_->HasTypeDirectory(
  98         SandboxFileSystemBackendDelegate::GetTypeString(type));
  99   }
 100
 101  private:
 102   scoped_ptr<ObfuscatedFileUtil::AbstractOriginEnumerator> enum_;
 103 };
 104
 105 void OpenFileSystemOnFileThread(
 106     ObfuscatedFileUtil* file_util,
 107     const GURL& origin_url,
 108     FileSystemType type,
 109     OpenFileSystemMode mode,
 110     base::PlatformFileError* error_ptr) {
 111   DCHECK(error_ptr);
 112   const bool create = (mode == OPEN_FILE_SYSTEM_CREATE_IF_NONEXISTENT);
 113   file_util->GetDirectoryForOriginAndType(
 114       origin_url, SandboxFileSystemBackendDelegate::GetTypeString(type),
 115       create, error_ptr);
 116   if (*error_ptr != base::PLATFORM_FILE_OK) {
 117     UMA_HISTOGRAM_ENUMERATION(kOpenFileSystemLabel,
 118                               kCreateDirectoryError,
 119                               kFileSystemErrorMax);
 120   } else {
 121     UMA_HISTOGRAM_ENUMERATION(kOpenFileSystemLabel, kOK, kFileSystemErrorMax);
 122   }
 123   // The reference of file_util will be derefed on the FILE thread
 124   // when the storage of this callback gets deleted regardless of whether
 125   // this method is called or not.
 126 }
 127
 128 void DidOpenFileSystem(
 129     base::WeakPtr<SandboxFileSystemBackendDelegate> delegate,
 130     const base::Callback<void(base::PlatformFileError error)>& callback,
 131     base::PlatformFileError* error) {
 132   if (delegate.get())
 133     delegate.get()->CollectOpenFileSystemMetrics(*error);
 134   callback.Run(*error);
 135 }
 136
 137 template <typename T>
 138 void DeleteSoon(base::SequencedTaskRunner* runner, T* ptr) {
 139   if (!runner->DeleteSoon(FROM_HERE, ptr))
 140     delete ptr;
 141 }
 142
 143 }  // namespace
 144
 145 const base::FilePath::CharType
 146 SandboxFileSystemBackendDelegate::kFileSystemDirectory[] =
 147     FILE_PATH_LITERAL("File System");
 148
 149 // static
 150 std::string SandboxFileSystemBackendDelegate::GetTypeString(
 151     FileSystemType type) {
 152   switch (type) {
 153     case kFileSystemTypeTemporary:
 154       return kTemporaryDirectoryName;
 155     case kFileSystemTypePersistent:
 156       return kPersistentDirectoryName;
 157     case kFileSystemTypeSyncable:
 158     case kFileSystemTypeSyncableForInternalSync:
 159       return kSyncableDirectoryName;
 160     case kFileSystemTypeUnknown:
 161     default:
 162       NOTREACHED() << "Unknown filesystem type requested:" << type;
 163       return std::string();
 164   }
 165 }
 166
 167 SandboxFileSystemBackendDelegate::SandboxFileSystemBackendDelegate(
 168     quota::QuotaManagerProxy* quota_manager_proxy,
 169     base::SequencedTaskRunner* file_task_runner,
 170     const base::FilePath& profile_path,
 171     quota::SpecialStoragePolicy* special_storage_policy,
 172     const FileSystemOptions& file_system_options)
 173     : file_task_runner_(file_task_runner),
 174       sandbox_file_util_(new AsyncFileUtilAdapter(
 175           new ObfuscatedFileUtil(
 176               special_storage_policy,
 177               profile_path.Append(kFileSystemDirectory),
 178               file_task_runner,
 179               base::Bind(&GetTypeStringForURL),
 180               GetKnownTypeStrings(),
 181               this))),
 182       file_system_usage_cache_(new FileSystemUsageCache(file_task_runner)),
 183       quota_observer_(new SandboxQuotaObserver(
 184           quota_manager_proxy,
 185           file_task_runner,
 186           obfuscated_file_util(),
 187           usage_cache())),
 188       special_storage_policy_(special_storage_policy),
 189       file_system_options_(file_system_options),
 190       is_filesystem_opened_(false),
 191       weak_factory_(this) {
 192   // Prepopulate database only if it can run asynchronously (i.e. the current
 193   // thread is not file_task_runner). Usually this is the case but may not
 194   // in test code.
 195   if (!file_task_runner_->RunsTasksOnCurrentThread()) {
 196     std::vector<std::string> types_to_prepopulate(
 197         &kPrepopulateTypes[0],
 198         &kPrepopulateTypes[arraysize(kPrepopulateTypes)]);
 199     file_task_runner_->PostTask(
 200         FROM_HERE,
 201         base::Bind(&ObfuscatedFileUtil::MaybePrepopulateDatabase,
 202                   base::Unretained(obfuscated_file_util()),
 203                   types_to_prepopulate));
 204   }
 205 }
 206
 207 SandboxFileSystemBackendDelegate::~SandboxFileSystemBackendDelegate() {
 208   io_thread_checker_.DetachFromThread();
 209
 210   if (!file_task_runner_->RunsTasksOnCurrentThread()) {
 211     DeleteSoon(file_task_runner_.get(), sandbox_file_util_.release());
 212     DeleteSoon(file_task_runner_.get(), quota_observer_.release());
 213     DeleteSoon(file_task_runner_.get(), file_system_usage_cache_.release());
 214   }
 215 }
 216
 217 SandboxFileSystemBackendDelegate::OriginEnumerator*
 218 SandboxFileSystemBackendDelegate::CreateOriginEnumerator() {
 219   return new ObfuscatedOriginEnumerator(obfuscated_file_util());
 220 }
 221
 222 base::FilePath
 223 SandboxFileSystemBackendDelegate::GetBaseDirectoryForOriginAndType(
 224     const GURL& origin_url,
 225     FileSystemType type,
 226     bool create) {
 227   base::PlatformFileError error = base::PLATFORM_FILE_OK;
 228   base::FilePath path = obfuscated_file_util()->GetDirectoryForOriginAndType(
 229       origin_url, GetTypeString(type), create, &error);
 230   if (error != base::PLATFORM_FILE_OK)
 231     return base::FilePath();
 232   return path;
 233 }
 234
 235 void SandboxFileSystemBackendDelegate::OpenFileSystem(
 236     const GURL& origin_url,
 237     FileSystemType type,
 238     OpenFileSystemMode mode,
 239     const OpenFileSystemCallback& callback,
 240     const GURL& root_url) {
 241   if (!IsAllowedScheme(origin_url)) {
 242     callback.Run(GURL(), std::string(), base::PLATFORM_FILE_ERROR_SECURITY);
 243     return;
 244   }
 245
 246   std::string name = GetFileSystemName(origin_url, type);
 247
 248   base::PlatformFileError* error_ptr = new base::PlatformFileError;
 249   file_task_runner_->PostTaskAndReply(
 250       FROM_HERE,
 251       base::Bind(&OpenFileSystemOnFileThread,
 252                  obfuscated_file_util(), origin_url, type, mode,
 253                  base::Unretained(error_ptr)),
 254       base::Bind(&DidOpenFileSystem,
 255                  weak_factory_.GetWeakPtr(),
 256                  base::Bind(callback, root_url, name),
 257                  base::Owned(error_ptr)));
 258
 259   io_thread_checker_.DetachFromThread();
 260   is_filesystem_opened_ = true;
 261 }
 262
 263 scoped_ptr<FileSystemOperationContext>
 264 SandboxFileSystemBackendDelegate::CreateFileSystemOperationContext(
 265     const FileSystemURL& url,
 266     FileSystemContext* context,
 267     base::PlatformFileError* error_code) const {
 268   if (!IsAccessValid(url)) {
 269     *error_code = base::PLATFORM_FILE_ERROR_SECURITY;
 270     return scoped_ptr<FileSystemOperationContext>();
 271   }
 272
 273   const UpdateObserverList* update_observers = GetUpdateObservers(url.type());
 274   const ChangeObserverList* change_observers = GetChangeObservers(url.type());
 275   DCHECK(update_observers);
 276
 277   scoped_ptr<FileSystemOperationContext> operation_context(
 278       new FileSystemOperationContext(context));
 279   operation_context->set_update_observers(*update_observers);
 280   operation_context->set_change_observers(
 281       change_observers ? *change_observers : ChangeObserverList());
 282
 283   return operation_context.Pass();
 284 }
 285
 286 scoped_ptr<webkit_blob::FileStreamReader>
 287 SandboxFileSystemBackendDelegate::CreateFileStreamReader(
 288     const FileSystemURL& url,
 289     int64 offset,
 290     const base::Time& expected_modification_time,
 291     FileSystemContext* context) const {
 292   if (!IsAccessValid(url))
 293     return scoped_ptr<webkit_blob::FileStreamReader>();
 294   return scoped_ptr<webkit_blob::FileStreamReader>(
 295       webkit_blob::FileStreamReader::CreateForFileSystemFile(
 296           context, url, offset, expected_modification_time));
 297 }
 298
 299 scoped_ptr<FileStreamWriter>
 300 SandboxFileSystemBackendDelegate::CreateFileStreamWriter(
 301     const FileSystemURL& url,
 302     int64 offset,
 303     FileSystemContext* context,
 304     FileSystemType type) const {
 305   if (!IsAccessValid(url))
 306     return scoped_ptr<FileStreamWriter>();
 307   const UpdateObserverList* observers = GetUpdateObservers(type);
 308   DCHECK(observers);
 309   return scoped_ptr<FileStreamWriter>(
 310       new SandboxFileStreamWriter(context, url, offset, *observers));
 311 }
 312
 313 base::PlatformFileError
 314 SandboxFileSystemBackendDelegate::DeleteOriginDataOnFileThread(
 315     FileSystemContext* file_system_context,
 316     quota::QuotaManagerProxy* proxy,
 317     const GURL& origin_url,
 318     FileSystemType type) {
 319   int64 usage = GetOriginUsageOnFileThread(
 320       file_system_context, origin_url, type);
 321   usage_cache()->CloseCacheFiles();
 322   bool result = obfuscated_file_util()->DeleteDirectoryForOriginAndType(
 323       origin_url, GetTypeString(type));
 324   if (result && proxy) {
 325     proxy->NotifyStorageModified(
 326         quota::QuotaClient::kFileSystem,
 327         origin_url,
 328         FileSystemTypeToQuotaStorageType(type),
 329         -usage);
 330   }
 331
 332   if (result)
 333     return base::PLATFORM_FILE_OK;
 334   return base::PLATFORM_FILE_ERROR_FAILED;
 335 }
 336
 337 void SandboxFileSystemBackendDelegate::GetOriginsForTypeOnFileThread(
 338     FileSystemType type, std::set<GURL>* origins) {
 339   DCHECK(origins);
 340   scoped_ptr<OriginEnumerator> enumerator(CreateOriginEnumerator());
 341   GURL origin;
 342   while (!(origin = enumerator->Next()).is_empty()) {
 343     if (enumerator->HasFileSystemType(type))
 344       origins->insert(origin);
 345   }
 346   switch (type) {
 347     case kFileSystemTypeTemporary:
 348       UMA_HISTOGRAM_COUNTS(kTemporaryOriginsCountLabel, origins->size());
 349       break;
 350     case kFileSystemTypePersistent:
 351       UMA_HISTOGRAM_COUNTS(kPersistentOriginsCountLabel, origins->size());
 352       break;
 353     default:
 354       break;
 355   }
 356 }
 357
 358 void SandboxFileSystemBackendDelegate::GetOriginsForHostOnFileThread(
 359     FileSystemType type, const std::string& host,
 360     std::set<GURL>* origins) {
 361   DCHECK(origins);
 362   scoped_ptr<OriginEnumerator> enumerator(CreateOriginEnumerator());
 363   GURL origin;
 364   while (!(origin = enumerator->Next()).is_empty()) {
 365     if (host == net::GetHostOrSpecFromURL(origin) &&
 366         enumerator->HasFileSystemType(type))
 367       origins->insert(origin);
 368   }
 369 }
 370
 371 int64 SandboxFileSystemBackendDelegate::GetOriginUsageOnFileThread(
 372     FileSystemContext* file_system_context,
 373     const GURL& origin_url,
 374     FileSystemType type) {
 375   // Don't use usage cache and return recalculated usage for sticky invalidated
 376   // origins.
 377   if (ContainsKey(sticky_dirty_origins_, std::make_pair(origin_url, type)))
 378     return RecalculateUsage(file_system_context, origin_url, type);
 379
 380   base::FilePath base_path =
 381       GetBaseDirectoryForOriginAndType(origin_url, type, false);
 382   if (base_path.empty() || !base::DirectoryExists(base_path))
 383     return 0;
 384   base::FilePath usage_file_path =
 385       base_path.Append(FileSystemUsageCache::kUsageFileName);
 386
 387   bool is_valid = usage_cache()->IsValid(usage_file_path);
 388   uint32 dirty_status = 0;
 389   bool dirty_status_available =
 390       usage_cache()->GetDirty(usage_file_path, &dirty_status);
 391   bool visited = !visited_origins_.insert(origin_url).second;
 392   if (is_valid && (dirty_status == 0 || (dirty_status_available && visited))) {
 393     // The usage cache is clean (dirty == 0) or the origin is already
 394     // initialized and running.  Read the cache file to get the usage.
 395     int64 usage = 0;
 396     return usage_cache()->GetUsage(usage_file_path, &usage) ? usage : -1;
 397   }
 398   // The usage cache has not been initialized or the cache is dirty.
 399   // Get the directory size now and update the cache.
 400   usage_cache()->Delete(usage_file_path);
 401
 402   int64 usage = RecalculateUsage(file_system_context, origin_url, type);
 403
 404   // This clears the dirty flag too.
 405   usage_cache()->UpdateUsage(usage_file_path, usage);
 406   return usage;
 407 }
 408
 409 void SandboxFileSystemBackendDelegate::AddFileUpdateObserver(
 410     FileSystemType type,
 411     FileUpdateObserver* observer,
 412     base::SequencedTaskRunner* task_runner) {
 413   DCHECK(!is_filesystem_opened_ || io_thread_checker_.CalledOnValidThread());
 414   update_observers_[type] =
 415       update_observers_[type].AddObserver(observer, task_runner);
 416 }
 417
 418 void SandboxFileSystemBackendDelegate::AddFileChangeObserver(
 419     FileSystemType type,
 420     FileChangeObserver* observer,
 421     base::SequencedTaskRunner* task_runner) {
 422   DCHECK(!is_filesystem_opened_ || io_thread_checker_.CalledOnValidThread());
 423   change_observers_[type] =
 424       change_observers_[type].AddObserver(observer, task_runner);
 425 }
 426
 427 void SandboxFileSystemBackendDelegate::AddFileAccessObserver(
 428     FileSystemType type,
 429     FileAccessObserver* observer,
 430     base::SequencedTaskRunner* task_runner) {
 431   DCHECK(!is_filesystem_opened_ || io_thread_checker_.CalledOnValidThread());
 432   access_observers_[type] =
 433       access_observers_[type].AddObserver(observer, task_runner);
 434 }
 435
 436 const UpdateObserverList* SandboxFileSystemBackendDelegate::GetUpdateObservers(
 437     FileSystemType type) const {
 438   std::map<FileSystemType, UpdateObserverList>::const_iterator iter =
 439       update_observers_.find(type);
 440   if (iter == update_observers_.end())
 441     return NULL;
 442   return &iter->second;
 443 }
 444
 445 const ChangeObserverList* SandboxFileSystemBackendDelegate::GetChangeObservers(
 446     FileSystemType type) const {
 447   std::map<FileSystemType, ChangeObserverList>::const_iterator iter =
 448       change_observers_.find(type);
 449   if (iter == change_observers_.end())
 450     return NULL;
 451   return &iter->second;
 452 }
 453
 454 const AccessObserverList* SandboxFileSystemBackendDelegate::GetAccessObservers(
 455     FileSystemType type) const {
 456   std::map<FileSystemType, AccessObserverList>::const_iterator iter =
 457       access_observers_.find(type);
 458   if (iter == access_observers_.end())
 459     return NULL;
 460   return &iter->second;
 461 }
 462
 463 void SandboxFileSystemBackendDelegate::RegisterQuotaUpdateObserver(
 464     FileSystemType type) {
 465   AddFileUpdateObserver(type, quota_observer_.get(), file_task_runner_.get());
 466 }
 467
 468 void SandboxFileSystemBackendDelegate::InvalidateUsageCache(
 469     const GURL& origin,
 470     FileSystemType type) {
 471   base::PlatformFileError error = base::PLATFORM_FILE_OK;
 472   base::FilePath usage_file_path = GetUsageCachePathForOriginAndType(
 473       obfuscated_file_util(), origin, type, &error);
 474   if (error != base::PLATFORM_FILE_OK)
 475     return;
 476   usage_cache()->IncrementDirty(usage_file_path);
 477 }
 478
 479 void SandboxFileSystemBackendDelegate::StickyInvalidateUsageCache(
 480     const GURL& origin,
 481     FileSystemType type) {
 482   sticky_dirty_origins_.insert(std::make_pair(origin, type));
 483   quota_observer()->SetUsageCacheEnabled(origin, type, false);
 484   InvalidateUsageCache(origin, type);
 485 }
 486
 487 FileSystemFileUtil* SandboxFileSystemBackendDelegate::sync_file_util() {
 488   return static_cast<AsyncFileUtilAdapter*>(file_util())->sync_file_util();
 489 }
 490
 491 bool SandboxFileSystemBackendDelegate::IsAccessValid(
 492     const FileSystemURL& url) const {
 493   if (!IsAllowedScheme(url.origin()))
 494     return false;
 495
 496   if (url.path().ReferencesParent())
 497     return false;
 498
 499   // Return earlier if the path is '/', because VirtualPath::BaseName()
 500   // returns '/' for '/' and we fail the "basename != '/'" check below.
 501   // (We exclude '.' because it's disallowed by spec.)
 502   if (VirtualPath::IsRootPath(url.path()) &&
 503       url.path() != base::FilePath(base::FilePath::kCurrentDirectory))
 504     return true;
 505
 506   // Restricted names specified in
 507   // http://dev.w3.org/2009/dap/file-system/file-dir-sys.html#naming-restrictions
 508   base::FilePath filename = VirtualPath::BaseName(url.path());
 509   // See if the name is allowed to create.
 510   for (size_t i = 0; i < arraysize(kRestrictedNames); ++i) {
 511     if (filename.value() == kRestrictedNames[i])
 512       return false;
 513   }
 514   for (size_t i = 0; i < arraysize(kRestrictedChars); ++i) {
 515     if (filename.value().find(kRestrictedChars[i]) !=
 516         base::FilePath::StringType::npos)
 517       return false;
 518   }
 519
 520   return true;
 521 }
 522
 523 bool SandboxFileSystemBackendDelegate::IsAllowedScheme(const GURL& url) const {
 524   // Basically we only accept http or https. We allow file:// URLs
 525   // only if --allow-file-access-from-files flag is given.
 526   if (url.SchemeIsHTTPOrHTTPS())
 527     return true;
 528   if (url.SchemeIsFileSystem())
 529     return url.inner_url() && IsAllowedScheme(*url.inner_url());
 530
 531   for (size_t i = 0;
 532        i < file_system_options_.additional_allowed_schemes().size();
 533        ++i) {
 534     if (url.SchemeIs(
 535             file_system_options_.additional_allowed_schemes()[i].c_str()))
 536       return true;
 537   }
 538   return false;
 539 }
 540
 541 base::FilePath
 542 SandboxFileSystemBackendDelegate::GetUsageCachePathForOriginAndType(
 543     const GURL& origin_url,
 544     FileSystemType type) {
 545   base::PlatformFileError error;
 546   base::FilePath path = GetUsageCachePathForOriginAndType(
 547       obfuscated_file_util(), origin_url, type, &error);
 548   if (error != base::PLATFORM_FILE_OK)
 549     return base::FilePath();
 550   return path;
 551 }
 552
 553 // static
 554 base::FilePath
 555 SandboxFileSystemBackendDelegate::GetUsageCachePathForOriginAndType(
 556     ObfuscatedFileUtil* sandbox_file_util,
 557     const GURL& origin_url,
 558     FileSystemType type,
 559     base::PlatformFileError* error_out) {
 560   DCHECK(error_out);
 561   *error_out = base::PLATFORM_FILE_OK;
 562   base::FilePath base_path = sandbox_file_util->GetDirectoryForOriginAndType(
 563       origin_url, GetTypeString(type), false /* create */, error_out);
 564   if (*error_out != base::PLATFORM_FILE_OK)
 565     return base::FilePath();
 566   return base_path.Append(FileSystemUsageCache::kUsageFileName);
 567 }
 568
 569 int64 SandboxFileSystemBackendDelegate::RecalculateUsage(
 570     FileSystemContext* context,
 571     const GURL& origin,
 572     FileSystemType type) {
 573   FileSystemOperationContext operation_context(context);
 574   FileSystemURL url = context->CreateCrackedFileSystemURL(
 575       origin, type, base::FilePath());
 576   scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator> enumerator(
 577       obfuscated_file_util()->CreateFileEnumerator(
 578           &operation_context, url, true));
 579
 580   base::FilePath file_path_each;
 581   int64 usage = 0;
 582
 583   while (!(file_path_each = enumerator->Next()).empty()) {
 584     usage += enumerator->Size();
 585     usage += ObfuscatedFileUtil::ComputeFilePathCost(file_path_each);
 586   }
 587
 588   return usage;
 589 }
 590
 591 void SandboxFileSystemBackendDelegate::CollectOpenFileSystemMetrics(
 592     base::PlatformFileError error_code) {
 593   base::Time now = base::Time::Now();
 594   bool throttled = now < next_release_time_for_open_filesystem_stat_;
 595   if (!throttled) {
 596     next_release_time_for_open_filesystem_stat_ =
 597         now + base::TimeDelta::FromHours(kMinimumStatsCollectionIntervalHours);
 598   }
 599
 600 #define REPORT(report_value)                                            \
 601   UMA_HISTOGRAM_ENUMERATION(kOpenFileSystemDetailLabel,                 \
 602                             (report_value),                             \
 603                             kFileSystemErrorMax);                       \
 604   if (!throttled) {                                                     \
 605     UMA_HISTOGRAM_ENUMERATION(kOpenFileSystemDetailNonThrottledLabel,   \
 606                               (report_value),                           \
 607                               kFileSystemErrorMax);                     \
 608   }
 609
 610   switch (error_code) {
 611     case base::PLATFORM_FILE_OK:
 612       REPORT(kOK);
 613       break;
 614     case base::PLATFORM_FILE_ERROR_INVALID_URL:
 615       REPORT(kInvalidSchemeError);
 616       break;
 617     case base::PLATFORM_FILE_ERROR_NOT_FOUND:
 618       REPORT(kNotFound);
 619       break;
 620     case base::PLATFORM_FILE_ERROR_FAILED:
 621     default:
 622       REPORT(kUnknownError);
 623       break;
 624   }
 625 #undef REPORT
 626 }
 627
 628 ObfuscatedFileUtil* SandboxFileSystemBackendDelegate::obfuscated_file_util() {
 629   return static_cast<ObfuscatedFileUtil*>(sync_file_util());
 630 }
 631
 632 // Declared in obfuscated_file_util.h.
 633 // static
 634 ObfuscatedFileUtil* ObfuscatedFileUtil::CreateForTesting(
 635     quota::SpecialStoragePolicy* special_storage_policy,
 636     const base::FilePath& file_system_directory,
 637     base::SequencedTaskRunner* file_task_runner) {
 638   return new ObfuscatedFileUtil(special_storage_policy,
 639                                 file_system_directory,
 640                                 file_task_runner,
 641                                 base::Bind(&GetTypeStringForURL),
 642                                 GetKnownTypeStrings(),
 643                                 NULL);
 644 }
 645
 646 }  // namespace fileapi