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