storage/browser/fileapi/obfuscated_file_util.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 "storage/browser/fileapi/obfuscated_file_util.h"
   6
   7 #include <queue>
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/files/file_util.h"
  12 #include "base/format_macros.h"
  13 #include "base/logging.h"
  14 #include "base/message_loop/message_loop.h"
  15 #include "base/metrics/histogram.h"
  16 #include "base/stl_util.h"
  17 #include "base/strings/string_number_conversions.h"
  18 #include "base/strings/string_util.h"
  19 #include "base/strings/stringprintf.h"
  20 #include "base/strings/sys_string_conversions.h"
  21 #include "base/strings/utf_string_conversions.h"
  22 #include "base/time/time.h"
  23 #include "storage/browser/fileapi/file_observers.h"
  24 #include "storage/browser/fileapi/file_system_context.h"
  25 #include "storage/browser/fileapi/file_system_operation_context.h"
  26 #include "storage/browser/fileapi/file_system_url.h"
  27 #include "storage/browser/fileapi/native_file_util.h"
  28 #include "storage/browser/fileapi/sandbox_file_system_backend.h"
  29 #include "storage/browser/fileapi/sandbox_isolated_origin_database.h"
  30 #include "storage/browser/fileapi/sandbox_origin_database.h"
  31 #include "storage/browser/fileapi/sandbox_prioritized_origin_database.h"
  32 #include "storage/browser/fileapi/timed_task_helper.h"
  33 #include "storage/browser/quota/quota_manager.h"
  34 #include "storage/common/database/database_identifier.h"
  35 #include "storage/common/fileapi/file_system_util.h"
  36 #include "url/gurl.h"
  37
  38 // Example of various paths:
  39 //   void ObfuscatedFileUtil::DoSomething(const FileSystemURL& url) {
  40 //     base::FilePath virtual_path = url.path();
  41 //     base::FilePath local_path = GetLocalFilePath(url);
  42 //
  43 //     NativeFileUtil::DoSomething(local_path);
  44 //     file_util::DoAnother(local_path);
  45 //  }
  46
  47 namespace storage {
  48
  49 namespace {
  50
  51 typedef SandboxDirectoryDatabase::FileId FileId;
  52 typedef SandboxDirectoryDatabase::FileInfo FileInfo;
  53
  54 void InitFileInfo(
  55     SandboxDirectoryDatabase::FileInfo* file_info,
  56     SandboxDirectoryDatabase::FileId parent_id,
  57     const base::FilePath::StringType& file_name) {
  58   DCHECK(file_info);
  59   file_info->parent_id = parent_id;
  60   file_info->name = file_name;
  61 }
  62
  63 // Costs computed as per crbug.com/86114, based on the LevelDB implementation of
  64 // path storage under Linux.  It's not clear if that will differ on Windows, on
  65 // which base::FilePath uses wide chars [since they're converted to UTF-8 for
  66 // storage anyway], but as long as the cost is high enough that one can't cheat
  67 // on quota by storing data in paths, it doesn't need to be all that accurate.
  68 const int64 kPathCreationQuotaCost = 146;  // Bytes per inode, basically.
  69 const int64 kPathByteQuotaCost = 2;  // Bytes per byte of path length in UTF-8.
  70
  71 const char kDirectoryDatabaseKeySeparator = ' ';
  72
  73 int64 UsageForPath(size_t length) {
  74   return kPathCreationQuotaCost +
  75       static_cast<int64>(length) * kPathByteQuotaCost;
  76 }
  77
  78 bool AllocateQuota(FileSystemOperationContext* context, int64 growth) {
  79   if (context->allowed_bytes_growth() == storage::QuotaManager::kNoLimit)
  80     return true;
  81
  82   int64 new_quota = context->allowed_bytes_growth() - growth;
  83   if (growth > 0 && new_quota < 0)
  84     return false;
  85   context->set_allowed_bytes_growth(new_quota);
  86   return true;
  87 }
  88
  89 void UpdateUsage(
  90     FileSystemOperationContext* context,
  91     const FileSystemURL& url,
  92     int64 growth) {
  93   context->update_observers()->Notify(
  94       &FileUpdateObserver::OnUpdate, MakeTuple(url, growth));
  95 }
  96
  97 void TouchDirectory(SandboxDirectoryDatabase* db, FileId dir_id) {
  98   DCHECK(db);
  99   if (!db->UpdateModificationTime(dir_id, base::Time::Now()))
 100     NOTREACHED();
 101 }
 102
 103 enum IsolatedOriginStatus {
 104   kIsolatedOriginMatch,
 105   kIsolatedOriginDontMatch,
 106   kIsolatedOriginStatusMax,
 107 };
 108
 109 }  // namespace
 110
 111 class ObfuscatedFileEnumerator
 112     : public FileSystemFileUtil::AbstractFileEnumerator {
 113  public:
 114   ObfuscatedFileEnumerator(
 115       SandboxDirectoryDatabase* db,
 116       FileSystemOperationContext* context,
 117       ObfuscatedFileUtil* obfuscated_file_util,
 118       const FileSystemURL& root_url,
 119       bool recursive)
 120       : db_(db),
 121         context_(context),
 122         obfuscated_file_util_(obfuscated_file_util),
 123         root_url_(root_url),
 124         recursive_(recursive),
 125         current_file_id_(0) {
 126     base::FilePath root_virtual_path = root_url.path();
 127     FileId file_id;
 128
 129     if (!db_->GetFileWithPath(root_virtual_path, &file_id))
 130       return;
 131
 132     FileRecord record = { file_id, root_virtual_path };
 133     recurse_queue_.push(record);
 134   }
 135
 136   ~ObfuscatedFileEnumerator() override {}
 137
 138   base::FilePath Next() override {
 139     ProcessRecurseQueue();
 140     if (display_stack_.empty())
 141       return base::FilePath();
 142
 143     current_file_id_ = display_stack_.back();
 144     display_stack_.pop_back();
 145
 146     FileInfo file_info;
 147     base::FilePath platform_file_path;
 148     base::File::Error error =
 149         obfuscated_file_util_->GetFileInfoInternal(
 150             db_, context_, root_url_, current_file_id_,
 151             &file_info, &current_platform_file_info_, &platform_file_path);
 152     if (error != base::File::FILE_OK)
 153       return Next();
 154
 155     base::FilePath virtual_path =
 156         current_parent_virtual_path_.Append(file_info.name);
 157     if (recursive_ && file_info.is_directory()) {
 158       FileRecord record = { current_file_id_, virtual_path };
 159       recurse_queue_.push(record);
 160     }
 161     return virtual_path;
 162   }
 163
 164   int64 Size() override { return current_platform_file_info_.size; }
 165
 166   base::Time LastModifiedTime() override {
 167     return current_platform_file_info_.last_modified;
 168   }
 169
 170   bool IsDirectory() override {
 171     return current_platform_file_info_.is_directory;
 172   }
 173
 174  private:
 175   typedef SandboxDirectoryDatabase::FileId FileId;
 176   typedef SandboxDirectoryDatabase::FileInfo FileInfo;
 177
 178   struct FileRecord {
 179     FileId file_id;
 180     base::FilePath virtual_path;
 181   };
 182
 183   void ProcessRecurseQueue() {
 184     while (display_stack_.empty() && !recurse_queue_.empty()) {
 185       FileRecord entry = recurse_queue_.front();
 186       recurse_queue_.pop();
 187       if (!db_->ListChildren(entry.file_id, &display_stack_)) {
 188         display_stack_.clear();
 189         return;
 190       }
 191       current_parent_virtual_path_ = entry.virtual_path;
 192     }
 193   }
 194
 195   SandboxDirectoryDatabase* db_;
 196   FileSystemOperationContext* context_;
 197   ObfuscatedFileUtil* obfuscated_file_util_;
 198   FileSystemURL root_url_;
 199   bool recursive_;
 200
 201   std::queue<FileRecord> recurse_queue_;
 202   std::vector<FileId> display_stack_;
 203   base::FilePath current_parent_virtual_path_;
 204
 205   FileId current_file_id_;
 206   base::File::Info current_platform_file_info_;
 207 };
 208
 209 class ObfuscatedOriginEnumerator
 210     : public ObfuscatedFileUtil::AbstractOriginEnumerator {
 211  public:
 212   typedef SandboxOriginDatabase::OriginRecord OriginRecord;
 213   ObfuscatedOriginEnumerator(
 214       SandboxOriginDatabaseInterface* origin_database,
 215       const base::FilePath& base_file_path)
 216       : base_file_path_(base_file_path) {
 217     if (origin_database)
 218       origin_database->ListAllOrigins(&origins_);
 219   }
 220
 221   ~ObfuscatedOriginEnumerator() override {}
 222
 223   // Returns the next origin.  Returns empty if there are no more origins.
 224   GURL Next() override {
 225     OriginRecord record;
 226     if (!origins_.empty()) {
 227       record = origins_.back();
 228       origins_.pop_back();
 229     }
 230     current_ = record;
 231     return storage::GetOriginFromIdentifier(record.origin);
 232   }
 233
 234   // Returns the current origin's information.
 235   bool HasTypeDirectory(const std::string& type_string) const override {
 236     if (current_.path.empty())
 237       return false;
 238     if (type_string.empty()) {
 239       NOTREACHED();
 240       return false;
 241     }
 242     base::FilePath path =
 243         base_file_path_.Append(current_.path).AppendASCII(type_string);
 244     return base::DirectoryExists(path);
 245   }
 246
 247  private:
 248   std::vector<OriginRecord> origins_;
 249   OriginRecord current_;
 250   base::FilePath base_file_path_;
 251 };
 252
 253 ObfuscatedFileUtil::ObfuscatedFileUtil(
 254     storage::SpecialStoragePolicy* special_storage_policy,
 255     const base::FilePath& file_system_directory,
 256     leveldb::Env* env_override,
 257     base::SequencedTaskRunner* file_task_runner,
 258     const GetTypeStringForURLCallback& get_type_string_for_url,
 259     const std::set<std::string>& known_type_strings,
 260     SandboxFileSystemBackendDelegate* sandbox_delegate)
 261     : special_storage_policy_(special_storage_policy),
 262       file_system_directory_(file_system_directory),
 263       env_override_(env_override),
 264       db_flush_delay_seconds_(10 * 60),  // 10 mins.
 265       file_task_runner_(file_task_runner),
 266       get_type_string_for_url_(get_type_string_for_url),
 267       known_type_strings_(known_type_strings),
 268       sandbox_delegate_(sandbox_delegate) {
 269 }
 270
 271 ObfuscatedFileUtil::~ObfuscatedFileUtil() {
 272   DropDatabases();
 273 }
 274
 275 base::File ObfuscatedFileUtil::CreateOrOpen(
 276     FileSystemOperationContext* context,
 277     const FileSystemURL& url, int file_flags) {
 278   base::File file = CreateOrOpenInternal(context, url, file_flags);
 279   if (file.IsValid() && file_flags & base::File::FLAG_WRITE &&
 280       context->quota_limit_type() == storage::kQuotaLimitTypeUnlimited &&
 281       sandbox_delegate_) {
 282     sandbox_delegate_->StickyInvalidateUsageCache(url.origin(), url.type());
 283   }
 284   return file.Pass();
 285 }
 286
 287 base::File::Error ObfuscatedFileUtil::EnsureFileExists(
 288     FileSystemOperationContext* context,
 289     const FileSystemURL& url,
 290     bool* created) {
 291   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, true);
 292   if (!db)
 293     return base::File::FILE_ERROR_FAILED;
 294
 295   FileId file_id;
 296   if (db->GetFileWithPath(url.path(), &file_id)) {
 297     FileInfo file_info;
 298     if (!db->GetFileInfo(file_id, &file_info)) {
 299       NOTREACHED();
 300       return base::File::FILE_ERROR_FAILED;
 301     }
 302     if (file_info.is_directory())
 303       return base::File::FILE_ERROR_NOT_A_FILE;
 304     if (created)
 305       *created = false;
 306     return base::File::FILE_OK;
 307   }
 308   FileId parent_id;
 309   if (!db->GetFileWithPath(VirtualPath::DirName(url.path()), &parent_id))
 310     return base::File::FILE_ERROR_NOT_FOUND;
 311
 312   FileInfo file_info;
 313   InitFileInfo(&file_info, parent_id,
 314                VirtualPath::BaseName(url.path()).value());
 315
 316   int64 growth = UsageForPath(file_info.name.size());
 317   if (!AllocateQuota(context, growth))
 318     return base::File::FILE_ERROR_NO_SPACE;
 319   base::File::Error error = CreateFile(context, base::FilePath(), url,
 320                                        &file_info);
 321   if (created && base::File::FILE_OK == error) {
 322     *created = true;
 323     UpdateUsage(context, url, growth);
 324     context->change_observers()->Notify(
 325         &FileChangeObserver::OnCreateFile, MakeTuple(url));
 326   }
 327   return error;
 328 }
 329
 330 base::File::Error ObfuscatedFileUtil::CreateDirectory(
 331     FileSystemOperationContext* context,
 332     const FileSystemURL& url,
 333     bool exclusive,
 334     bool recursive) {
 335   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, true);
 336   if (!db)
 337     return base::File::FILE_ERROR_FAILED;
 338
 339   FileId file_id;
 340   if (db->GetFileWithPath(url.path(), &file_id)) {
 341     FileInfo file_info;
 342     if (exclusive)
 343       return base::File::FILE_ERROR_EXISTS;
 344     if (!db->GetFileInfo(file_id, &file_info)) {
 345       NOTREACHED();
 346       return base::File::FILE_ERROR_FAILED;
 347     }
 348     if (!file_info.is_directory())
 349       return base::File::FILE_ERROR_NOT_A_DIRECTORY;
 350     return base::File::FILE_OK;
 351   }
 352
 353   std::vector<base::FilePath::StringType> components;
 354   VirtualPath::GetComponents(url.path(), &components);
 355   FileId parent_id = 0;
 356   size_t index;
 357   for (index = 0; index < components.size(); ++index) {
 358     base::FilePath::StringType name = components[index];
 359     if (name == FILE_PATH_LITERAL("/"))
 360       continue;
 361     if (!db->GetChildWithName(parent_id, name, &parent_id))
 362       break;
 363   }
 364   if (!db->IsDirectory(parent_id))
 365     return base::File::FILE_ERROR_NOT_A_DIRECTORY;
 366   if (!recursive && components.size() - index > 1)
 367     return base::File::FILE_ERROR_NOT_FOUND;
 368   bool first = true;
 369   for (; index < components.size(); ++index) {
 370     FileInfo file_info;
 371     file_info.name = components[index];
 372     if (file_info.name == FILE_PATH_LITERAL("/"))
 373       continue;
 374     file_info.modification_time = base::Time::Now();
 375     file_info.parent_id = parent_id;
 376     int64 growth = UsageForPath(file_info.name.size());
 377     if (!AllocateQuota(context, growth))
 378       return base::File::FILE_ERROR_NO_SPACE;
 379     base::File::Error error = db->AddFileInfo(file_info, &parent_id);
 380     if (error != base::File::FILE_OK)
 381       return error;
 382     UpdateUsage(context, url, growth);
 383     context->change_observers()->Notify(
 384         &FileChangeObserver::OnCreateDirectory, MakeTuple(url));
 385     if (first) {
 386       first = false;
 387       TouchDirectory(db, file_info.parent_id);
 388     }
 389   }
 390   return base::File::FILE_OK;
 391 }
 392
 393 base::File::Error ObfuscatedFileUtil::GetFileInfo(
 394     FileSystemOperationContext* context,
 395     const FileSystemURL& url,
 396     base::File::Info* file_info,
 397     base::FilePath* platform_file_path) {
 398   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, false);
 399   if (!db)
 400     return base::File::FILE_ERROR_NOT_FOUND;
 401   FileId file_id;
 402   if (!db->GetFileWithPath(url.path(), &file_id))
 403     return base::File::FILE_ERROR_NOT_FOUND;
 404   FileInfo local_info;
 405   return GetFileInfoInternal(db, context, url,
 406                              file_id, &local_info,
 407                              file_info, platform_file_path);
 408 }
 409
 410 scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
 411     ObfuscatedFileUtil::CreateFileEnumerator(
 412     FileSystemOperationContext* context,
 413     const FileSystemURL& root_url) {
 414   return CreateFileEnumerator(context, root_url, false /* recursive */);
 415 }
 416
 417 base::File::Error ObfuscatedFileUtil::GetLocalFilePath(
 418     FileSystemOperationContext* context,
 419     const FileSystemURL& url,
 420     base::FilePath* local_path) {
 421   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, false);
 422   if (!db)
 423     return base::File::FILE_ERROR_NOT_FOUND;
 424   FileId file_id;
 425   if (!db->GetFileWithPath(url.path(), &file_id))
 426     return base::File::FILE_ERROR_NOT_FOUND;
 427   FileInfo file_info;
 428   if (!db->GetFileInfo(file_id, &file_info) || file_info.is_directory()) {
 429     NOTREACHED();
 430     // Directories have no local file path.
 431     return base::File::FILE_ERROR_NOT_FOUND;
 432   }
 433   *local_path = DataPathToLocalPath(url, file_info.data_path);
 434
 435   if (local_path->empty())
 436     return base::File::FILE_ERROR_NOT_FOUND;
 437   return base::File::FILE_OK;
 438 }
 439
 440 base::File::Error ObfuscatedFileUtil::Touch(
 441     FileSystemOperationContext* context,
 442     const FileSystemURL& url,
 443     const base::Time& last_access_time,
 444     const base::Time& last_modified_time) {
 445   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, false);
 446   if (!db)
 447     return base::File::FILE_ERROR_NOT_FOUND;
 448   FileId file_id;
 449   if (!db->GetFileWithPath(url.path(), &file_id))
 450     return base::File::FILE_ERROR_NOT_FOUND;
 451
 452   FileInfo file_info;
 453   if (!db->GetFileInfo(file_id, &file_info)) {
 454     NOTREACHED();
 455     return base::File::FILE_ERROR_FAILED;
 456   }
 457   if (file_info.is_directory()) {
 458     if (!db->UpdateModificationTime(file_id, last_modified_time))
 459       return base::File::FILE_ERROR_FAILED;
 460     return base::File::FILE_OK;
 461   }
 462   return NativeFileUtil::Touch(
 463       DataPathToLocalPath(url, file_info.data_path),
 464       last_access_time, last_modified_time);
 465 }
 466
 467 base::File::Error ObfuscatedFileUtil::Truncate(
 468     FileSystemOperationContext* context,
 469     const FileSystemURL& url,
 470     int64 length) {
 471   base::File::Info file_info;
 472   base::FilePath local_path;
 473   base::File::Error error =
 474       GetFileInfo(context, url, &file_info, &local_path);
 475   if (error != base::File::FILE_OK)
 476     return error;
 477
 478   int64 growth = length - file_info.size;
 479   if (!AllocateQuota(context, growth))
 480     return base::File::FILE_ERROR_NO_SPACE;
 481   error = NativeFileUtil::Truncate(local_path, length);
 482   if (error == base::File::FILE_OK) {
 483     UpdateUsage(context, url, growth);
 484     context->change_observers()->Notify(
 485         &FileChangeObserver::OnModifyFile, MakeTuple(url));
 486   }
 487   return error;
 488 }
 489
 490 base::File::Error ObfuscatedFileUtil::CopyOrMoveFile(
 491     FileSystemOperationContext* context,
 492     const FileSystemURL& src_url,
 493     const FileSystemURL& dest_url,
 494     CopyOrMoveOption option,
 495     bool copy) {
 496   // Cross-filesystem copies and moves should be handled via CopyInForeignFile.
 497   DCHECK(src_url.origin() == dest_url.origin());
 498   DCHECK(src_url.type() == dest_url.type());
 499
 500   SandboxDirectoryDatabase* db = GetDirectoryDatabase(src_url, true);
 501   if (!db)
 502     return base::File::FILE_ERROR_FAILED;
 503
 504   FileId src_file_id;
 505   if (!db->GetFileWithPath(src_url.path(), &src_file_id))
 506     return base::File::FILE_ERROR_NOT_FOUND;
 507
 508   FileId dest_file_id;
 509   bool overwrite = db->GetFileWithPath(dest_url.path(),
 510                                        &dest_file_id);
 511
 512   FileInfo src_file_info;
 513   base::File::Info src_platform_file_info;
 514   base::FilePath src_local_path;
 515   base::File::Error error = GetFileInfoInternal(
 516       db, context, src_url, src_file_id,
 517       &src_file_info, &src_platform_file_info, &src_local_path);
 518   if (error != base::File::FILE_OK)
 519     return error;
 520   if (src_file_info.is_directory())
 521     return base::File::FILE_ERROR_NOT_A_FILE;
 522
 523   FileInfo dest_file_info;
 524   base::File::Info dest_platform_file_info;  // overwrite case only
 525   base::FilePath dest_local_path;  // overwrite case only
 526   if (overwrite) {
 527     base::File::Error error = GetFileInfoInternal(
 528         db, context, dest_url, dest_file_id,
 529         &dest_file_info, &dest_platform_file_info, &dest_local_path);
 530     if (error == base::File::FILE_ERROR_NOT_FOUND)
 531       overwrite = false;  // fallback to non-overwrite case
 532     else if (error != base::File::FILE_OK)
 533       return error;
 534     else if (dest_file_info.is_directory())
 535       return base::File::FILE_ERROR_INVALID_OPERATION;
 536   }
 537   if (!overwrite) {
 538     FileId dest_parent_id;
 539     if (!db->GetFileWithPath(VirtualPath::DirName(dest_url.path()),
 540                              &dest_parent_id)) {
 541       return base::File::FILE_ERROR_NOT_FOUND;
 542     }
 543
 544     dest_file_info = src_file_info;
 545     dest_file_info.parent_id = dest_parent_id;
 546     dest_file_info.name =
 547         VirtualPath::BaseName(dest_url.path()).value();
 548   }
 549
 550   int64 growth = 0;
 551   if (copy)
 552     growth += src_platform_file_info.size;
 553   else
 554     growth -= UsageForPath(src_file_info.name.size());
 555   if (overwrite)
 556     growth -= dest_platform_file_info.size;
 557   else
 558     growth += UsageForPath(dest_file_info.name.size());
 559   if (!AllocateQuota(context, growth))
 560     return base::File::FILE_ERROR_NO_SPACE;
 561
 562   /*
 563    * Copy-with-overwrite
 564    *  Just overwrite data file
 565    * Copy-without-overwrite
 566    *  Copy backing file
 567    *  Create new metadata pointing to new backing file.
 568    * Move-with-overwrite
 569    *  transaction:
 570    *    Remove source entry.
 571    *    Point target entry to source entry's backing file.
 572    *  Delete target entry's old backing file
 573    * Move-without-overwrite
 574    *  Just update metadata
 575    */
 576   error = base::File::FILE_ERROR_FAILED;
 577   if (copy) {
 578     if (overwrite) {
 579       error = NativeFileUtil::CopyOrMoveFile(
 580           src_local_path,
 581           dest_local_path,
 582           option,
 583           storage::NativeFileUtil::CopyOrMoveModeForDestination(
 584               dest_url, true /* copy */));
 585     } else {  // non-overwrite
 586       error = CreateFile(context, src_local_path, dest_url, &dest_file_info);
 587     }
 588   } else {
 589     if (overwrite) {
 590       if (db->OverwritingMoveFile(src_file_id, dest_file_id)) {
 591         if (base::File::FILE_OK !=
 592             NativeFileUtil::DeleteFile(dest_local_path))
 593           LOG(WARNING) << "Leaked a backing file.";
 594         error = base::File::FILE_OK;
 595       } else {
 596         error = base::File::FILE_ERROR_FAILED;
 597       }
 598     } else {  // non-overwrite
 599       if (db->UpdateFileInfo(src_file_id, dest_file_info))
 600         error = base::File::FILE_OK;
 601       else
 602         error = base::File::FILE_ERROR_FAILED;
 603     }
 604   }
 605
 606   if (error != base::File::FILE_OK)
 607     return error;
 608
 609   if (overwrite) {
 610     context->change_observers()->Notify(
 611         &FileChangeObserver::OnModifyFile,
 612         MakeTuple(dest_url));
 613   } else {
 614     context->change_observers()->Notify(
 615         &FileChangeObserver::OnCreateFileFrom,
 616         MakeTuple(dest_url, src_url));
 617   }
 618
 619   if (!copy) {
 620     context->change_observers()->Notify(
 621         &FileChangeObserver::OnRemoveFile, MakeTuple(src_url));
 622     TouchDirectory(db, src_file_info.parent_id);
 623   }
 624
 625   TouchDirectory(db, dest_file_info.parent_id);
 626
 627   UpdateUsage(context, dest_url, growth);
 628   return error;
 629 }
 630
 631 base::File::Error ObfuscatedFileUtil::CopyInForeignFile(
 632     FileSystemOperationContext* context,
 633     const base::FilePath& src_file_path,
 634     const FileSystemURL& dest_url) {
 635   SandboxDirectoryDatabase* db = GetDirectoryDatabase(dest_url, true);
 636   if (!db)
 637     return base::File::FILE_ERROR_FAILED;
 638
 639   base::File::Info src_platform_file_info;
 640   if (!base::GetFileInfo(src_file_path, &src_platform_file_info))
 641     return base::File::FILE_ERROR_NOT_FOUND;
 642
 643   FileId dest_file_id;
 644   bool overwrite = db->GetFileWithPath(dest_url.path(),
 645                                        &dest_file_id);
 646
 647   FileInfo dest_file_info;
 648   base::File::Info dest_platform_file_info;  // overwrite case only
 649   if (overwrite) {
 650     base::FilePath dest_local_path;
 651     base::File::Error error = GetFileInfoInternal(
 652         db, context, dest_url, dest_file_id,
 653         &dest_file_info, &dest_platform_file_info, &dest_local_path);
 654     if (error == base::File::FILE_ERROR_NOT_FOUND)
 655       overwrite = false;  // fallback to non-overwrite case
 656     else if (error != base::File::FILE_OK)
 657       return error;
 658     else if (dest_file_info.is_directory())
 659       return base::File::FILE_ERROR_INVALID_OPERATION;
 660   }
 661   if (!overwrite) {
 662     FileId dest_parent_id;
 663     if (!db->GetFileWithPath(VirtualPath::DirName(dest_url.path()),
 664                              &dest_parent_id)) {
 665       return base::File::FILE_ERROR_NOT_FOUND;
 666     }
 667     if (!dest_file_info.is_directory())
 668       return base::File::FILE_ERROR_FAILED;
 669     InitFileInfo(&dest_file_info, dest_parent_id,
 670                  VirtualPath::BaseName(dest_url.path()).value());
 671   }
 672
 673   int64 growth = src_platform_file_info.size;
 674   if (overwrite)
 675     growth -= dest_platform_file_info.size;
 676   else
 677     growth += UsageForPath(dest_file_info.name.size());
 678   if (!AllocateQuota(context, growth))
 679     return base::File::FILE_ERROR_NO_SPACE;
 680
 681   base::File::Error error;
 682   if (overwrite) {
 683     base::FilePath dest_local_path =
 684         DataPathToLocalPath(dest_url, dest_file_info.data_path);
 685     error = NativeFileUtil::CopyOrMoveFile(
 686         src_file_path,
 687         dest_local_path,
 688         FileSystemOperation::OPTION_NONE,
 689         storage::NativeFileUtil::CopyOrMoveModeForDestination(dest_url,
 690                                                               true /* copy */));
 691   } else {
 692     error = CreateFile(context, src_file_path, dest_url, &dest_file_info);
 693   }
 694
 695   if (error != base::File::FILE_OK)
 696     return error;
 697
 698   if (overwrite) {
 699     context->change_observers()->Notify(
 700         &FileChangeObserver::OnModifyFile, MakeTuple(dest_url));
 701   } else {
 702     context->change_observers()->Notify(
 703         &FileChangeObserver::OnCreateFile, MakeTuple(dest_url));
 704   }
 705
 706   UpdateUsage(context, dest_url, growth);
 707   TouchDirectory(db, dest_file_info.parent_id);
 708   return base::File::FILE_OK;
 709 }
 710
 711 base::File::Error ObfuscatedFileUtil::DeleteFile(
 712     FileSystemOperationContext* context,
 713     const FileSystemURL& url) {
 714   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, true);
 715   if (!db)
 716     return base::File::FILE_ERROR_FAILED;
 717   FileId file_id;
 718   if (!db->GetFileWithPath(url.path(), &file_id))
 719     return base::File::FILE_ERROR_NOT_FOUND;
 720
 721   FileInfo file_info;
 722   base::File::Info platform_file_info;
 723   base::FilePath local_path;
 724   base::File::Error error = GetFileInfoInternal(
 725       db, context, url, file_id, &file_info, &platform_file_info, &local_path);
 726   if (error != base::File::FILE_ERROR_NOT_FOUND &&
 727       error != base::File::FILE_OK)
 728     return error;
 729
 730   if (file_info.is_directory())
 731     return base::File::FILE_ERROR_NOT_A_FILE;
 732
 733   int64 growth = -UsageForPath(file_info.name.size()) - platform_file_info.size;
 734   AllocateQuota(context, growth);
 735   if (!db->RemoveFileInfo(file_id)) {
 736     NOTREACHED();
 737     return base::File::FILE_ERROR_FAILED;
 738   }
 739   UpdateUsage(context, url, growth);
 740   TouchDirectory(db, file_info.parent_id);
 741
 742   context->change_observers()->Notify(
 743       &FileChangeObserver::OnRemoveFile, MakeTuple(url));
 744
 745   if (error == base::File::FILE_ERROR_NOT_FOUND)
 746     return base::File::FILE_OK;
 747
 748   error = NativeFileUtil::DeleteFile(local_path);
 749   if (base::File::FILE_OK != error)
 750     LOG(WARNING) << "Leaked a backing file.";
 751   return base::File::FILE_OK;
 752 }
 753
 754 base::File::Error ObfuscatedFileUtil::DeleteDirectory(
 755     FileSystemOperationContext* context,
 756     const FileSystemURL& url) {
 757   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, true);
 758   if (!db)
 759     return base::File::FILE_ERROR_FAILED;
 760
 761   FileId file_id;
 762   if (!db->GetFileWithPath(url.path(), &file_id))
 763     return base::File::FILE_ERROR_NOT_FOUND;
 764   FileInfo file_info;
 765   if (!db->GetFileInfo(file_id, &file_info)) {
 766     NOTREACHED();
 767     return base::File::FILE_ERROR_FAILED;
 768   }
 769   if (!file_info.is_directory())
 770     return base::File::FILE_ERROR_NOT_A_DIRECTORY;
 771   if (!db->RemoveFileInfo(file_id))
 772     return base::File::FILE_ERROR_NOT_EMPTY;
 773   int64 growth = -UsageForPath(file_info.name.size());
 774   AllocateQuota(context, growth);
 775   UpdateUsage(context, url, growth);
 776   TouchDirectory(db, file_info.parent_id);
 777   context->change_observers()->Notify(
 778       &FileChangeObserver::OnRemoveDirectory, MakeTuple(url));
 779   return base::File::FILE_OK;
 780 }
 781
 782 storage::ScopedFile ObfuscatedFileUtil::CreateSnapshotFile(
 783     FileSystemOperationContext* context,
 784     const FileSystemURL& url,
 785     base::File::Error* error,
 786     base::File::Info* file_info,
 787     base::FilePath* platform_path) {
 788   // We're just returning the local file information.
 789   *error = GetFileInfo(context, url, file_info, platform_path);
 790   if (*error == base::File::FILE_OK && file_info->is_directory) {
 791     *file_info = base::File::Info();
 792     *error = base::File::FILE_ERROR_NOT_A_FILE;
 793   }
 794   return storage::ScopedFile();
 795 }
 796
 797 scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
 798     ObfuscatedFileUtil::CreateFileEnumerator(
 799     FileSystemOperationContext* context,
 800     const FileSystemURL& root_url,
 801     bool recursive) {
 802   SandboxDirectoryDatabase* db = GetDirectoryDatabase(root_url, false);
 803   if (!db) {
 804     return scoped_ptr<AbstractFileEnumerator>(new EmptyFileEnumerator());
 805   }
 806   return scoped_ptr<AbstractFileEnumerator>(
 807       new ObfuscatedFileEnumerator(db, context, this, root_url, recursive));
 808 }
 809
 810 bool ObfuscatedFileUtil::IsDirectoryEmpty(
 811     FileSystemOperationContext* context,
 812     const FileSystemURL& url) {
 813   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, false);
 814   if (!db)
 815     return true;  // Not a great answer, but it's what others do.
 816   FileId file_id;
 817   if (!db->GetFileWithPath(url.path(), &file_id))
 818     return true;  // Ditto.
 819   FileInfo file_info;
 820   if (!db->GetFileInfo(file_id, &file_info)) {
 821     DCHECK(!file_id);
 822     // It's the root directory and the database hasn't been initialized yet.
 823     return true;
 824   }
 825   if (!file_info.is_directory())
 826     return true;
 827   std::vector<FileId> children;
 828   // TODO(ericu): This could easily be made faster with help from the database.
 829   if (!db->ListChildren(file_id, &children))
 830     return true;
 831   return children.empty();
 832 }
 833
 834 base::FilePath ObfuscatedFileUtil::GetDirectoryForOriginAndType(
 835     const GURL& origin,
 836     const std::string& type_string,
 837     bool create,
 838     base::File::Error* error_code) {
 839   base::FilePath origin_dir = GetDirectoryForOrigin(origin, create, error_code);
 840   if (origin_dir.empty())
 841     return base::FilePath();
 842   if (type_string.empty())
 843     return origin_dir;
 844   base::FilePath path = origin_dir.AppendASCII(type_string);
 845   base::File::Error error = base::File::FILE_OK;
 846   if (!base::DirectoryExists(path) &&
 847       (!create || !base::CreateDirectory(path))) {
 848     error = create ?
 849           base::File::FILE_ERROR_FAILED :
 850           base::File::FILE_ERROR_NOT_FOUND;
 851   }
 852
 853   if (error_code)
 854     *error_code = error;
 855   return path;
 856 }
 857
 858 bool ObfuscatedFileUtil::DeleteDirectoryForOriginAndType(
 859     const GURL& origin,
 860     const std::string& type_string) {
 861   DestroyDirectoryDatabase(origin, type_string);
 862
 863   const base::FilePath origin_path = GetDirectoryForOrigin(origin, false, NULL);
 864   if (!type_string.empty()) {
 865     // Delete the filesystem type directory.
 866     base::File::Error error = base::File::FILE_OK;
 867     const base::FilePath origin_type_path =
 868         GetDirectoryForOriginAndType(origin, type_string, false, &error);
 869     if (error == base::File::FILE_ERROR_FAILED)
 870       return false;
 871     if (error == base::File::FILE_OK &&
 872         !origin_type_path.empty() &&
 873         !base::DeleteFile(origin_type_path, true /* recursive */)) {
 874       return false;
 875     }
 876
 877     // At this point we are sure we had successfully deleted the origin/type
 878     // directory (i.e. we're ready to just return true).
 879     // See if we have other directories in this origin directory.
 880     for (std::set<std::string>::iterator iter = known_type_strings_.begin();
 881          iter != known_type_strings_.end();
 882          ++iter) {
 883       if (*iter == type_string)
 884         continue;
 885       if (base::DirectoryExists(origin_path.AppendASCII(*iter))) {
 886         // Other type's directory exists; just return true here.
 887         return true;
 888       }
 889     }
 890   }
 891
 892   // No other directories seem exist. Try deleting the entire origin directory.
 893   InitOriginDatabase(origin, false);
 894   if (origin_database_) {
 895     origin_database_->RemovePathForOrigin(
 896         storage::GetIdentifierFromOrigin(origin));
 897   }
 898   return base::DeleteFile(origin_path, true /* recursive */);
 899 }
 900
 901 ObfuscatedFileUtil::AbstractOriginEnumerator*
 902 ObfuscatedFileUtil::CreateOriginEnumerator() {
 903   std::vector<SandboxOriginDatabase::OriginRecord> origins;
 904
 905   InitOriginDatabase(GURL(), false);
 906   return new ObfuscatedOriginEnumerator(
 907       origin_database_.get(), file_system_directory_);
 908 }
 909
 910 void ObfuscatedFileUtil::DestroyDirectoryDatabase(
 911     const GURL& origin,
 912     const std::string& type_string) {
 913   // If |type_string| is empty, delete all filesystem types under |origin|.
 914   const std::string key_prefix = GetDirectoryDatabaseKey(origin, type_string);
 915   for (DirectoryMap::iterator iter = directories_.lower_bound(key_prefix);
 916        iter != directories_.end();) {
 917     if (!StartsWithASCII(iter->first, key_prefix, true))
 918       break;
 919     DCHECK(type_string.empty() || iter->first == key_prefix);
 920     scoped_ptr<SandboxDirectoryDatabase> database(iter->second);
 921     directories_.erase(iter++);
 922
 923     // Continue to destroy databases even if it failed because it doesn't affect
 924     // the final result.
 925     database->DestroyDatabase();
 926   }
 927 }
 928
 929 // static
 930 int64 ObfuscatedFileUtil::ComputeFilePathCost(const base::FilePath& path) {
 931   return UsageForPath(VirtualPath::BaseName(path).value().size());
 932 }
 933
 934 void ObfuscatedFileUtil::MaybePrepopulateDatabase(
 935     const std::vector<std::string>& type_strings_to_prepopulate) {
 936   SandboxPrioritizedOriginDatabase database(file_system_directory_,
 937                                             env_override_);
 938   std::string origin_string = database.GetPrimaryOrigin();
 939   if (origin_string.empty() || !database.HasOriginPath(origin_string))
 940     return;
 941   const GURL origin = storage::GetOriginFromIdentifier(origin_string);
 942
 943   // Prepopulate the directory database(s) if and only if this instance
 944   // has primary origin and the directory database is already there.
 945   for (size_t i = 0; i < type_strings_to_prepopulate.size(); ++i) {
 946     const std::string type_string = type_strings_to_prepopulate[i];
 947     // Only handles known types.
 948     if (!ContainsKey(known_type_strings_, type_string))
 949       continue;
 950     base::File::Error error = base::File::FILE_ERROR_FAILED;
 951     base::FilePath path = GetDirectoryForOriginAndType(
 952         origin, type_string, false, &error);
 953     if (error != base::File::FILE_OK)
 954       continue;
 955     scoped_ptr<SandboxDirectoryDatabase> db(
 956         new SandboxDirectoryDatabase(path, env_override_));
 957     if (db->Init(SandboxDirectoryDatabase::FAIL_ON_CORRUPTION)) {
 958       directories_[GetDirectoryDatabaseKey(origin, type_string)] = db.release();
 959       MarkUsed();
 960       // Don't populate more than one database, as it may rather hurt
 961       // performance.
 962       break;
 963     }
 964   }
 965 }
 966
 967 base::FilePath ObfuscatedFileUtil::GetDirectoryForURL(
 968     const FileSystemURL& url,
 969     bool create,
 970     base::File::Error* error_code) {
 971   return GetDirectoryForOriginAndType(
 972       url.origin(), CallGetTypeStringForURL(url), create, error_code);
 973 }
 974
 975 std::string ObfuscatedFileUtil::CallGetTypeStringForURL(
 976     const FileSystemURL& url) {
 977   DCHECK(!get_type_string_for_url_.is_null());
 978   return get_type_string_for_url_.Run(url);
 979 }
 980
 981 base::File::Error ObfuscatedFileUtil::GetFileInfoInternal(
 982     SandboxDirectoryDatabase* db,
 983     FileSystemOperationContext* context,
 984     const FileSystemURL& url,
 985     FileId file_id,
 986     FileInfo* local_info,
 987     base::File::Info* file_info,
 988     base::FilePath* platform_file_path) {
 989   DCHECK(db);
 990   DCHECK(context);
 991   DCHECK(file_info);
 992   DCHECK(platform_file_path);
 993
 994   if (!db->GetFileInfo(file_id, local_info)) {
 995     NOTREACHED();
 996     return base::File::FILE_ERROR_FAILED;
 997   }
 998
 999   if (local_info->is_directory()) {
1000     file_info->size = 0;
1001     file_info->is_directory = true;
1002     file_info->is_symbolic_link = false;
1003     file_info->last_modified = local_info->modification_time;
1004     *platform_file_path = base::FilePath();
1005     // We don't fill in ctime or atime.
1006     return base::File::FILE_OK;
1007   }
1008   if (local_info->data_path.empty())
1009     return base::File::FILE_ERROR_INVALID_OPERATION;
1010   base::FilePath local_path = DataPathToLocalPath(url, local_info->data_path);
1011   base::File::Error error = NativeFileUtil::GetFileInfo(
1012       local_path, file_info);
1013   // We should not follow symbolic links in sandboxed file system.
1014   if (base::IsLink(local_path)) {
1015     LOG(WARNING) << "Found a symbolic file.";
1016     error = base::File::FILE_ERROR_NOT_FOUND;
1017   }
1018   if (error == base::File::FILE_OK) {
1019     *platform_file_path = local_path;
1020   } else if (error == base::File::FILE_ERROR_NOT_FOUND) {
1021     LOG(WARNING) << "Lost a backing file.";
1022     InvalidateUsageCache(context, url.origin(), url.type());
1023     if (!db->RemoveFileInfo(file_id))
1024       return base::File::FILE_ERROR_FAILED;
1025   }
1026   return error;
1027 }
1028
1029 base::File ObfuscatedFileUtil::CreateAndOpenFile(
1030     FileSystemOperationContext* context,
1031     const FileSystemURL& dest_url,
1032     FileInfo* dest_file_info, int file_flags) {
1033   SandboxDirectoryDatabase* db = GetDirectoryDatabase(dest_url, true);
1034
1035   base::FilePath root, dest_local_path;
1036   base::File::Error error = GenerateNewLocalPath(db, context, dest_url, &root,
1037                                                  &dest_local_path);
1038   if (error != base::File::FILE_OK)
1039     return base::File(error);
1040
1041   if (base::PathExists(dest_local_path)) {
1042     if (!base::DeleteFile(dest_local_path, true /* recursive */))
1043       return base::File(base::File::FILE_ERROR_FAILED);
1044     LOG(WARNING) << "A stray file detected";
1045     InvalidateUsageCache(context, dest_url.origin(), dest_url.type());
1046   }
1047
1048   base::File file = NativeFileUtil::CreateOrOpen(dest_local_path, file_flags);
1049   if (!file.IsValid())
1050     return file.Pass();
1051
1052   if (!file.created()) {
1053     file.Close();
1054     base::DeleteFile(dest_local_path, false /* recursive */);
1055     return base::File(base::File::FILE_ERROR_FAILED);
1056   }
1057
1058   error = CommitCreateFile(root, dest_local_path, db, dest_file_info);
1059   if (error != base::File::FILE_OK) {
1060     file.Close();
1061     base::DeleteFile(dest_local_path, false /* recursive */);
1062     return base::File(error);
1063   }
1064
1065   return file.Pass();
1066 }
1067
1068 base::File::Error ObfuscatedFileUtil::CreateFile(
1069     FileSystemOperationContext* context,
1070     const base::FilePath& src_file_path,
1071     const FileSystemURL& dest_url,
1072     FileInfo* dest_file_info) {
1073   SandboxDirectoryDatabase* db = GetDirectoryDatabase(dest_url, true);
1074
1075   base::FilePath root, dest_local_path;
1076   base::File::Error error = GenerateNewLocalPath(db, context, dest_url, &root,
1077                                                  &dest_local_path);
1078   if (error != base::File::FILE_OK)
1079     return error;
1080
1081   bool created = false;
1082   if (src_file_path.empty()) {
1083     if (base::PathExists(dest_local_path)) {
1084       if (!base::DeleteFile(dest_local_path, true /* recursive */))
1085         return base::File::FILE_ERROR_FAILED;
1086       LOG(WARNING) << "A stray file detected";
1087       InvalidateUsageCache(context, dest_url.origin(), dest_url.type());
1088     }
1089
1090     error = NativeFileUtil::EnsureFileExists(dest_local_path, &created);
1091   } else {
1092     error = NativeFileUtil::CopyOrMoveFile(
1093         src_file_path,
1094         dest_local_path,
1095         FileSystemOperation::OPTION_NONE,
1096         storage::NativeFileUtil::CopyOrMoveModeForDestination(dest_url,
1097                                                               true /* copy */));
1098     created = true;
1099   }
1100   if (error != base::File::FILE_OK)
1101     return error;
1102   if (!created)
1103     return base::File::FILE_ERROR_FAILED;
1104
1105   return CommitCreateFile(root, dest_local_path, db, dest_file_info);
1106 }
1107
1108 base::File::Error ObfuscatedFileUtil::CommitCreateFile(
1109     const base::FilePath& root,
1110     const base::FilePath& local_path,
1111     SandboxDirectoryDatabase* db,
1112     FileInfo* dest_file_info) {
1113   // This removes the root, including the trailing slash, leaving a relative
1114   // path.
1115   dest_file_info->data_path = base::FilePath(
1116       local_path.value().substr(root.value().length() + 1));
1117
1118   FileId file_id;
1119   base::File::Error error = db->AddFileInfo(*dest_file_info, &file_id);
1120   if (error != base::File::FILE_OK)
1121     return error;
1122
1123   TouchDirectory(db, dest_file_info->parent_id);
1124   return base::File::FILE_OK;
1125 }
1126
1127 base::FilePath ObfuscatedFileUtil::DataPathToLocalPath(
1128     const FileSystemURL& url, const base::FilePath& data_path) {
1129   base::File::Error error = base::File::FILE_OK;
1130   base::FilePath root = GetDirectoryForURL(url, false, &error);
1131   if (error != base::File::FILE_OK)
1132     return base::FilePath();
1133   return root.Append(data_path);
1134 }
1135
1136 std::string ObfuscatedFileUtil::GetDirectoryDatabaseKey(
1137     const GURL& origin, const std::string& type_string) {
1138   // For isolated origin we just use a type string as a key.
1139   return storage::GetIdentifierFromOrigin(origin) +
1140       kDirectoryDatabaseKeySeparator + type_string;
1141 }
1142
1143 // TODO(ericu): How to do the whole validation-without-creation thing?
1144 // We may not have quota even to create the database.
1145 // Ah, in that case don't even get here?
1146 // Still doesn't answer the quota issue, though.
1147 SandboxDirectoryDatabase* ObfuscatedFileUtil::GetDirectoryDatabase(
1148     const FileSystemURL& url, bool create) {
1149   std::string key = GetDirectoryDatabaseKey(
1150       url.origin(), CallGetTypeStringForURL(url));
1151   if (key.empty())
1152     return NULL;
1153
1154   DirectoryMap::iterator iter = directories_.find(key);
1155   if (iter != directories_.end()) {
1156     MarkUsed();
1157     return iter->second;
1158   }
1159
1160   base::File::Error error = base::File::FILE_OK;
1161   base::FilePath path = GetDirectoryForURL(url, create, &error);
1162   if (error != base::File::FILE_OK) {
1163     LOG(WARNING) << "Failed to get origin+type directory: "
1164                  << url.DebugString() << " error:" << error;
1165     return NULL;
1166   }
1167   MarkUsed();
1168   SandboxDirectoryDatabase* database =
1169       new SandboxDirectoryDatabase(path, env_override_);
1170   directories_[key] = database;
1171   return database;
1172 }
1173
1174 base::FilePath ObfuscatedFileUtil::GetDirectoryForOrigin(
1175     const GURL& origin, bool create, base::File::Error* error_code) {
1176   if (!InitOriginDatabase(origin, create)) {
1177     if (error_code) {
1178       *error_code = create ?
1179           base::File::FILE_ERROR_FAILED :
1180           base::File::FILE_ERROR_NOT_FOUND;
1181     }
1182     return base::FilePath();
1183   }
1184   base::FilePath directory_name;
1185   std::string id = storage::GetIdentifierFromOrigin(origin);
1186
1187   bool exists_in_db = origin_database_->HasOriginPath(id);
1188   if (!exists_in_db && !create) {
1189     if (error_code)
1190       *error_code = base::File::FILE_ERROR_NOT_FOUND;
1191     return base::FilePath();
1192   }
1193   if (!origin_database_->GetPathForOrigin(id, &directory_name)) {
1194     if (error_code)
1195       *error_code = base::File::FILE_ERROR_FAILED;
1196     return base::FilePath();
1197   }
1198
1199   base::FilePath path = file_system_directory_.Append(directory_name);
1200   bool exists_in_fs = base::DirectoryExists(path);
1201   if (!exists_in_db && exists_in_fs) {
1202     if (!base::DeleteFile(path, true)) {
1203       if (error_code)
1204         *error_code = base::File::FILE_ERROR_FAILED;
1205       return base::FilePath();
1206     }
1207     exists_in_fs = false;
1208   }
1209
1210   if (!exists_in_fs) {
1211     if (!create || !base::CreateDirectory(path)) {
1212       if (error_code)
1213         *error_code = create ?
1214             base::File::FILE_ERROR_FAILED :
1215             base::File::FILE_ERROR_NOT_FOUND;
1216       return base::FilePath();
1217     }
1218   }
1219
1220   if (error_code)
1221     *error_code = base::File::FILE_OK;
1222
1223   return path;
1224 }
1225
1226 void ObfuscatedFileUtil::InvalidateUsageCache(
1227     FileSystemOperationContext* context,
1228     const GURL& origin,
1229     FileSystemType type) {
1230   if (sandbox_delegate_)
1231     sandbox_delegate_->InvalidateUsageCache(origin, type);
1232 }
1233
1234 void ObfuscatedFileUtil::MarkUsed() {
1235   if (!timer_)
1236     timer_.reset(new TimedTaskHelper(file_task_runner_.get()));
1237
1238   if (timer_->IsRunning()) {
1239     timer_->Reset();
1240   } else {
1241     timer_->Start(FROM_HERE,
1242                   base::TimeDelta::FromSeconds(db_flush_delay_seconds_),
1243                   base::Bind(&ObfuscatedFileUtil::DropDatabases,
1244                              base::Unretained(this)));
1245   }
1246 }
1247
1248 void ObfuscatedFileUtil::DropDatabases() {
1249   origin_database_.reset();
1250   STLDeleteContainerPairSecondPointers(
1251       directories_.begin(), directories_.end());
1252   directories_.clear();
1253   timer_.reset();
1254 }
1255
1256 bool ObfuscatedFileUtil::InitOriginDatabase(const GURL& origin_hint,
1257                                             bool create) {
1258   if (origin_database_)
1259     return true;
1260
1261   if (!create && !base::DirectoryExists(file_system_directory_))
1262     return false;
1263   if (!base::CreateDirectory(file_system_directory_)) {
1264     LOG(WARNING) << "Failed to create FileSystem directory: " <<
1265         file_system_directory_.value();
1266     return false;
1267   }
1268
1269   SandboxPrioritizedOriginDatabase* prioritized_origin_database =
1270       new SandboxPrioritizedOriginDatabase(file_system_directory_,
1271                                            env_override_);
1272   origin_database_.reset(prioritized_origin_database);
1273
1274   if (origin_hint.is_empty() || !HasIsolatedStorage(origin_hint))
1275     return true;
1276
1277   const std::string isolated_origin_string =
1278       storage::GetIdentifierFromOrigin(origin_hint);
1279
1280   // TODO(kinuko): Deprecate this after a few release cycles, e.g. around M33.
1281   base::FilePath isolated_origin_dir = file_system_directory_.Append(
1282       SandboxIsolatedOriginDatabase::kObsoleteOriginDirectory);
1283   if (base::DirectoryExists(isolated_origin_dir) &&
1284       prioritized_origin_database->GetSandboxOriginDatabase()) {
1285     SandboxIsolatedOriginDatabase::MigrateBackFromObsoleteOriginDatabase(
1286         isolated_origin_string,
1287         file_system_directory_,
1288         prioritized_origin_database->GetSandboxOriginDatabase());
1289   }
1290
1291   prioritized_origin_database->InitializePrimaryOrigin(
1292       isolated_origin_string);
1293
1294   return true;
1295 }
1296
1297 base::File::Error ObfuscatedFileUtil::GenerateNewLocalPath(
1298     SandboxDirectoryDatabase* db,
1299     FileSystemOperationContext* context,
1300     const FileSystemURL& url,
1301     base::FilePath* root,
1302     base::FilePath* local_path) {
1303   DCHECK(local_path);
1304   int64 number;
1305   if (!db || !db->GetNextInteger(&number))
1306     return base::File::FILE_ERROR_FAILED;
1307
1308   base::File::Error error = base::File::FILE_OK;
1309   *root = GetDirectoryForURL(url, false, &error);
1310   if (error != base::File::FILE_OK)
1311     return error;
1312
1313   // We use the third- and fourth-to-last digits as the directory.
1314   int64 directory_number = number % 10000 / 100;
1315   base::FilePath new_local_path = root->AppendASCII(
1316       base::StringPrintf("%02" PRId64, directory_number));
1317
1318   error = NativeFileUtil::CreateDirectory(
1319       new_local_path, false /* exclusive */, false /* recursive */);
1320   if (error != base::File::FILE_OK)
1321     return error;
1322
1323   *local_path =
1324       new_local_path.AppendASCII(base::StringPrintf("%08" PRId64, number));
1325   return base::File::FILE_OK;
1326 }
1327
1328 base::File ObfuscatedFileUtil::CreateOrOpenInternal(
1329     FileSystemOperationContext* context,
1330     const FileSystemURL& url, int file_flags) {
1331   DCHECK(!(file_flags & (base::File::FLAG_DELETE_ON_CLOSE |
1332         base::File::FLAG_HIDDEN | base::File::FLAG_EXCLUSIVE_READ |
1333         base::File::FLAG_EXCLUSIVE_WRITE)));
1334   SandboxDirectoryDatabase* db = GetDirectoryDatabase(url, true);
1335   if (!db)
1336     return base::File(base::File::FILE_ERROR_FAILED);
1337   FileId file_id;
1338   if (!db->GetFileWithPath(url.path(), &file_id)) {
1339     // The file doesn't exist.
1340     if (!(file_flags & (base::File::FLAG_CREATE |
1341         base::File::FLAG_CREATE_ALWAYS | base::File::FLAG_OPEN_ALWAYS))) {
1342       return base::File(base::File::FILE_ERROR_NOT_FOUND);
1343     }
1344     FileId parent_id;
1345     if (!db->GetFileWithPath(VirtualPath::DirName(url.path()), &parent_id))
1346       return base::File(base::File::FILE_ERROR_NOT_FOUND);
1347     FileInfo file_info;
1348     InitFileInfo(&file_info, parent_id,
1349                  VirtualPath::BaseName(url.path()).value());
1350
1351     int64 growth = UsageForPath(file_info.name.size());
1352     if (!AllocateQuota(context, growth))
1353       return base::File(base::File::FILE_ERROR_NO_SPACE);
1354     base::File file = CreateAndOpenFile(context, url, &file_info, file_flags);
1355     if (file.IsValid()) {
1356       UpdateUsage(context, url, growth);
1357       context->change_observers()->Notify(
1358           &FileChangeObserver::OnCreateFile, MakeTuple(url));
1359     }
1360     return file.Pass();
1361   }
1362
1363   if (file_flags & base::File::FLAG_CREATE)
1364     return base::File(base::File::FILE_ERROR_EXISTS);
1365
1366   base::File::Info platform_file_info;
1367   base::FilePath local_path;
1368   FileInfo file_info;
1369   base::File::Error error = GetFileInfoInternal(
1370       db, context, url, file_id, &file_info, &platform_file_info, &local_path);
1371   if (error != base::File::FILE_OK)
1372     return base::File(error);
1373   if (file_info.is_directory())
1374     return base::File(base::File::FILE_ERROR_NOT_A_FILE);
1375
1376   int64 delta = 0;
1377   if (file_flags & (base::File::FLAG_CREATE_ALWAYS |
1378                     base::File::FLAG_OPEN_TRUNCATED)) {
1379     // The file exists and we're truncating.
1380     delta = -platform_file_info.size;
1381     AllocateQuota(context, delta);
1382   }
1383
1384   base::File file = NativeFileUtil::CreateOrOpen(local_path, file_flags);
1385   if (!file.IsValid()) {
1386     error = file.error_details();
1387     if (error == base::File::FILE_ERROR_NOT_FOUND) {
1388       // TODO(tzik): Also invalidate on-memory usage cache in UsageTracker.
1389       // TODO(tzik): Delete database entry after ensuring the file lost.
1390       InvalidateUsageCache(context, url.origin(), url.type());
1391       LOG(WARNING) << "Lost a backing file.";
1392       return base::File(base::File::FILE_ERROR_FAILED);
1393     }
1394     return file.Pass();
1395   }
1396
1397   // If truncating we need to update the usage.
1398   if (delta) {
1399     UpdateUsage(context, url, delta);
1400     context->change_observers()->Notify(
1401         &FileChangeObserver::OnModifyFile, MakeTuple(url));
1402   }
1403   return file.Pass();
1404 }
1405
1406 bool ObfuscatedFileUtil::HasIsolatedStorage(const GURL& origin) {
1407   return special_storage_policy_.get() &&
1408       special_storage_policy_->HasIsolatedStorage(origin);
1409 }
1410
1411 }  // namespace storage