chrome/installer/util/install_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 // See the corresponding header file for description of the functions in this
   6 // file.
   7
   8 #include "chrome/installer/util/install_util.h"
   9
  10 #include <shellapi.h>
  11 #include <shlobj.h>
  12 #include <shlwapi.h>
  13
  14 #include <algorithm>
  15
  16 #include "base/command_line.h"
  17 #include "base/files/file_util.h"
  18 #include "base/logging.h"
  19 #include "base/memory/scoped_ptr.h"
  20 #include "base/path_service.h"
  21 #include "base/process/launch.h"
  22 #include "base/strings/string_util.h"
  23 #include "base/strings/utf_string_conversions.h"
  24 #include "base/sys_info.h"
  25 #include "base/values.h"
  26 #include "base/version.h"
  27 #include "base/win/metro.h"
  28 #include "base/win/registry.h"
  29 #include "base/win/windows_version.h"
  30 #include "chrome/common/chrome_constants.h"
  31 #include "chrome/common/chrome_paths.h"
  32 #include "chrome/installer/util/browser_distribution.h"
  33 #include "chrome/installer/util/google_update_constants.h"
  34 #include "chrome/installer/util/helper.h"
  35 #include "chrome/installer/util/installation_state.h"
  36 #include "chrome/installer/util/l10n_string_util.h"
  37 #include "chrome/installer/util/util_constants.h"
  38 #include "chrome/installer/util/work_item_list.h"
  39
  40 using base::win::RegKey;
  41 using installer::ProductState;
  42
  43 namespace {
  44
  45 const wchar_t kStageBinaryPatching[] = L"binary_patching";
  46 const wchar_t kStageBuilding[] = L"building";
  47 const wchar_t kStageConfiguringAutoLaunch[] = L"configuring_auto_launch";
  48 const wchar_t kStageCopyingPreferencesFile[] = L"copying_prefs";
  49 const wchar_t kStageCreatingShortcuts[] = L"creating_shortcuts";
  50 const wchar_t kStageEnsemblePatching[] = L"ensemble_patching";
  51 const wchar_t kStageExecuting[] = L"executing";
  52 const wchar_t kStageFinishing[] = L"finishing";
  53 const wchar_t kStagePreconditions[] = L"preconditions";
  54 const wchar_t kStageRefreshingPolicy[] = L"refreshing_policy";
  55 const wchar_t kStageRegisteringChrome[] = L"registering_chrome";
  56 const wchar_t kStageRemovingOldVersions[] = L"removing_old_ver";
  57 const wchar_t kStageRollingback[] = L"rollingback";
  58 const wchar_t kStageUncompressing[] = L"uncompressing";
  59 const wchar_t kStageUnpacking[] = L"unpacking";
  60 const wchar_t kStageUpdatingChannels[] = L"updating_channels";
  61 const wchar_t kStageCreatingVisualManifest[] = L"creating_visual_manifest";
  62 const wchar_t kStageDeferringToHigherVersion[] = L"deferring_to_higher_version";
  63 const wchar_t kStageUninstallingBinaries[] = L"uninstalling_binaries";
  64 const wchar_t kStageUninstallingChromeFrame[] = L"uninstalling_chrome_frame";
  65
  66 const wchar_t* const kStages[] = {
  67   NULL,
  68   kStagePreconditions,
  69   kStageUncompressing,
  70   kStageEnsemblePatching,
  71   kStageBinaryPatching,
  72   kStageUnpacking,
  73   kStageBuilding,
  74   kStageExecuting,
  75   kStageRollingback,
  76   kStageRefreshingPolicy,
  77   kStageUpdatingChannels,
  78   kStageCopyingPreferencesFile,
  79   kStageCreatingShortcuts,
  80   kStageRegisteringChrome,
  81   kStageRemovingOldVersions,
  82   kStageFinishing,
  83   kStageConfiguringAutoLaunch,
  84   kStageCreatingVisualManifest,
  85   kStageDeferringToHigherVersion,
  86   kStageUninstallingBinaries,
  87   kStageUninstallingChromeFrame,
  88 };
  89
  90 COMPILE_ASSERT(installer::NUM_STAGES == arraysize(kStages),
  91                kStages_disagrees_with_Stage_comma_they_must_match_bang);
  92
  93 // Creates a zero-sized non-decorated foreground window that doesn't appear
  94 // in the taskbar. This is used as a parent window for calls to ShellExecuteEx
  95 // in order for the UAC dialog to appear in the foreground and for focus
  96 // to be returned to this process once the UAC task is dismissed. Returns
  97 // NULL on failure, a handle to the UAC window on success.
  98 HWND CreateUACForegroundWindow() {
  99   HWND foreground_window = ::CreateWindowEx(WS_EX_TOOLWINDOW,
 100                                             L"STATIC",
 101                                             NULL,
 102                                             WS_POPUP | WS_VISIBLE,
 103                                             0, 0, 0, 0,
 104                                             NULL, NULL,
 105                                             ::GetModuleHandle(NULL),
 106                                             NULL);
 107   if (foreground_window) {
 108     HMONITOR monitor = ::MonitorFromWindow(foreground_window,
 109                                            MONITOR_DEFAULTTONEAREST);
 110     if (monitor) {
 111       MONITORINFO mi = {0};
 112       mi.cbSize = sizeof(mi);
 113       ::GetMonitorInfo(monitor, &mi);
 114       RECT screen_rect = mi.rcWork;
 115       int x_offset = (screen_rect.right - screen_rect.left) / 2;
 116       int y_offset = (screen_rect.bottom - screen_rect.top) / 2;
 117       ::MoveWindow(foreground_window,
 118                    screen_rect.left + x_offset,
 119                    screen_rect.top + y_offset,
 120                    0, 0, FALSE);
 121     } else {
 122       NOTREACHED() << "Unable to get default monitor";
 123     }
 124     ::SetForegroundWindow(foreground_window);
 125   }
 126   return foreground_window;
 127 }
 128
 129 }  // namespace
 130
 131 base::string16 InstallUtil::GetActiveSetupPath(BrowserDistribution* dist) {
 132   static const wchar_t kInstalledComponentsPath[] =
 133       L"Software\\Microsoft\\Active Setup\\Installed Components\\";
 134   return kInstalledComponentsPath + dist->GetActiveSetupGuid();
 135 }
 136
 137 void InstallUtil::TriggerActiveSetupCommand() {
 138   base::string16 active_setup_reg(
 139       GetActiveSetupPath(BrowserDistribution::GetDistribution()));
 140   base::win::RegKey active_setup_key(
 141       HKEY_LOCAL_MACHINE, active_setup_reg.c_str(), KEY_QUERY_VALUE);
 142   base::string16 cmd_str;
 143   LONG read_status = active_setup_key.ReadValue(L"StubPath", &cmd_str);
 144   if (read_status != ERROR_SUCCESS) {
 145     LOG(ERROR) << active_setup_reg << ", " << read_status;
 146     // This should never fail if Chrome is registered at system-level, but if it
 147     // does there is not much else to be done.
 148     return;
 149   }
 150
 151   CommandLine cmd(CommandLine::FromString(cmd_str));
 152   // Force creation of shortcuts as the First Run beacon might land between now
 153   // and the time setup.exe checks for it.
 154   cmd.AppendSwitch(installer::switches::kForceConfigureUserSettings);
 155
 156   base::LaunchOptions launch_options;
 157   if (base::win::IsMetroProcess())
 158     launch_options.force_breakaway_from_job_ = true;
 159   if (!base::LaunchProcess(cmd.GetCommandLineString(), launch_options, NULL))
 160     PLOG(ERROR) << cmd.GetCommandLineString();
 161 }
 162
 163 bool InstallUtil::ExecuteExeAsAdmin(const CommandLine& cmd, DWORD* exit_code) {
 164   base::FilePath::StringType program(cmd.GetProgram().value());
 165   DCHECK(!program.empty());
 166   DCHECK_NE(program[0], L'\"');
 167
 168   CommandLine::StringType params(cmd.GetCommandLineString());
 169   if (params[0] == '"') {
 170     DCHECK_EQ('"', params[program.length() + 1]);
 171     DCHECK_EQ(program, params.substr(1, program.length()));
 172     params = params.substr(program.length() + 2);
 173   } else {
 174     DCHECK_EQ(program, params.substr(0, program.length()));
 175     params = params.substr(program.length());
 176   }
 177
 178   base::TrimWhitespace(params, base::TRIM_ALL, &params);
 179
 180   HWND uac_foreground_window = CreateUACForegroundWindow();
 181
 182   SHELLEXECUTEINFO info = {0};
 183   info.cbSize = sizeof(SHELLEXECUTEINFO);
 184   info.fMask = SEE_MASK_NOCLOSEPROCESS;
 185   info.hwnd = uac_foreground_window;
 186   info.lpVerb = L"runas";
 187   info.lpFile = program.c_str();
 188   info.lpParameters = params.c_str();
 189   info.nShow = SW_SHOW;
 190
 191   bool success = false;
 192   if (::ShellExecuteEx(&info) == TRUE) {
 193     ::WaitForSingleObject(info.hProcess, INFINITE);
 194     DWORD ret_val = 0;
 195     if (::GetExitCodeProcess(info.hProcess, &ret_val)) {
 196       success = true;
 197       if (exit_code)
 198         *exit_code = ret_val;
 199     }
 200   }
 201
 202   if (uac_foreground_window) {
 203     DestroyWindow(uac_foreground_window);
 204   }
 205
 206   return success;
 207 }
 208
 209 CommandLine InstallUtil::GetChromeUninstallCmd(
 210     bool system_install, BrowserDistribution::Type distribution_type) {
 211   ProductState state;
 212   if (state.Initialize(system_install, distribution_type)) {
 213     return state.uninstall_command();
 214   }
 215   return CommandLine(CommandLine::NO_PROGRAM);
 216 }
 217
 218 void InstallUtil::GetChromeVersion(BrowserDistribution* dist,
 219                                    bool system_install,
 220                                    Version* version) {
 221   DCHECK(dist);
 222   RegKey key;
 223   HKEY reg_root = (system_install) ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
 224   LONG result = key.Open(reg_root,
 225                          dist->GetVersionKey().c_str(),
 226                          KEY_QUERY_VALUE | KEY_WOW64_32KEY);
 227
 228   base::string16 version_str;
 229   if (result == ERROR_SUCCESS)
 230     result = key.ReadValue(google_update::kRegVersionField, &version_str);
 231
 232   *version = Version();
 233   if (result == ERROR_SUCCESS && !version_str.empty()) {
 234     VLOG(1) << "Existing " << dist->GetDisplayName() << " version found "
 235             << version_str;
 236     *version = Version(base::UTF16ToASCII(version_str));
 237   } else {
 238     DCHECK_EQ(ERROR_FILE_NOT_FOUND, result);
 239     VLOG(1) << "No existing " << dist->GetDisplayName()
 240             << " install found.";
 241   }
 242 }
 243
 244 void InstallUtil::GetCriticalUpdateVersion(BrowserDistribution* dist,
 245                                            bool system_install,
 246                                            Version* version) {
 247   DCHECK(dist);
 248   RegKey key;
 249   HKEY reg_root = (system_install) ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
 250   LONG result = key.Open(reg_root,
 251                          dist->GetVersionKey().c_str(),
 252                          KEY_QUERY_VALUE | KEY_WOW64_32KEY);
 253
 254   base::string16 version_str;
 255   if (result == ERROR_SUCCESS)
 256     result = key.ReadValue(google_update::kRegCriticalVersionField,
 257                            &version_str);
 258
 259   *version = Version();
 260   if (result == ERROR_SUCCESS && !version_str.empty()) {
 261     VLOG(1) << "Critical Update version for " << dist->GetDisplayName()
 262             << " found " << version_str;
 263     *version = Version(base::UTF16ToASCII(version_str));
 264   } else {
 265     DCHECK_EQ(ERROR_FILE_NOT_FOUND, result);
 266     VLOG(1) << "No existing " << dist->GetDisplayName()
 267             << " install found.";
 268   }
 269 }
 270
 271 bool InstallUtil::IsOSSupported() {
 272   // We do not support Win2K or older, or XP without service pack 2.
 273   VLOG(1) << base::SysInfo::OperatingSystemName() << ' '
 274           << base::SysInfo::OperatingSystemVersion();
 275   base::win::Version version = base::win::GetVersion();
 276   return (version > base::win::VERSION_XP) ||
 277       ((version == base::win::VERSION_XP) &&
 278        (base::win::OSInfo::GetInstance()->service_pack().major >= 2));
 279 }
 280
 281 void InstallUtil::AddInstallerResultItems(
 282     bool system_install,
 283     const base::string16& state_key,
 284     installer::InstallStatus status,
 285     int string_resource_id,
 286     const base::string16* const launch_cmd,
 287     WorkItemList* install_list) {
 288   DCHECK(install_list);
 289   const HKEY root = system_install ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
 290   DWORD installer_result = (GetInstallReturnCode(status) == 0) ? 0 : 1;
 291   install_list->AddCreateRegKeyWorkItem(root, state_key, KEY_WOW64_32KEY);
 292   install_list->AddSetRegValueWorkItem(root,
 293                                        state_key,
 294                                        KEY_WOW64_32KEY,
 295                                        installer::kInstallerResult,
 296                                        installer_result,
 297                                        true);
 298   install_list->AddSetRegValueWorkItem(root,
 299                                        state_key,
 300                                        KEY_WOW64_32KEY,
 301                                        installer::kInstallerError,
 302                                        static_cast<DWORD>(status),
 303                                        true);
 304   if (string_resource_id != 0) {
 305     base::string16 msg = installer::GetLocalizedString(string_resource_id);
 306     install_list->AddSetRegValueWorkItem(root,
 307                                          state_key,
 308                                          KEY_WOW64_32KEY,
 309                                          installer::kInstallerResultUIString,
 310                                          msg,
 311                                          true);
 312   }
 313   if (launch_cmd != NULL && !launch_cmd->empty()) {
 314     install_list->AddSetRegValueWorkItem(
 315         root,
 316         state_key,
 317         KEY_WOW64_32KEY,
 318         installer::kInstallerSuccessLaunchCmdLine,
 319         *launch_cmd,
 320         true);
 321   }
 322 }
 323
 324 void InstallUtil::UpdateInstallerStage(bool system_install,
 325                                        const base::string16& state_key_path,
 326                                        installer::InstallerStage stage) {
 327   DCHECK_LE(static_cast<installer::InstallerStage>(0), stage);
 328   DCHECK_GT(installer::NUM_STAGES, stage);
 329   const HKEY root = system_install ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
 330   RegKey state_key;
 331   LONG result =
 332       state_key.Open(root,
 333                      state_key_path.c_str(),
 334                      KEY_QUERY_VALUE | KEY_SET_VALUE | KEY_WOW64_32KEY);
 335   if (result == ERROR_SUCCESS) {
 336     if (stage == installer::NO_STAGE) {
 337       result = state_key.DeleteValue(installer::kInstallerExtraCode1);
 338       LOG_IF(ERROR, result != ERROR_SUCCESS && result != ERROR_FILE_NOT_FOUND)
 339           << "Failed deleting installer stage from " << state_key_path
 340           << "; result: " << result;
 341     } else {
 342       const DWORD extra_code_1 = static_cast<DWORD>(stage);
 343       result = state_key.WriteValue(installer::kInstallerExtraCode1,
 344                                     extra_code_1);
 345       LOG_IF(ERROR, result != ERROR_SUCCESS)
 346           << "Failed writing installer stage to " << state_key_path
 347           << "; result: " << result;
 348     }
 349     // TODO(grt): Remove code below here once we're convinced that our use of
 350     // Google Update's new InstallerExtraCode1 value is good.
 351     installer::ChannelInfo channel_info;
 352     // This will return false if the "ap" value isn't present, which is fine.
 353     channel_info.Initialize(state_key);
 354     if (channel_info.SetStage(kStages[stage]) &&
 355         !channel_info.Write(&state_key)) {
 356       LOG(ERROR) << "Failed writing installer stage to " << state_key_path;
 357     }
 358   } else {
 359     LOG(ERROR) << "Failed opening " << state_key_path
 360                << " to update installer stage; result: " << result;
 361   }
 362 }
 363
 364 bool InstallUtil::IsPerUserInstall(const wchar_t* const exe_path) {
 365   wchar_t program_files_path[MAX_PATH] = {0};
 366   if (SUCCEEDED(SHGetFolderPath(NULL, CSIDL_PROGRAM_FILES, NULL,
 367                                 SHGFP_TYPE_CURRENT, program_files_path))) {
 368     return !StartsWith(exe_path, program_files_path, false);
 369   } else {
 370     NOTREACHED();
 371   }
 372   return true;
 373 }
 374
 375 bool InstallUtil::IsMultiInstall(BrowserDistribution* dist,
 376                                  bool system_install) {
 377   DCHECK(dist);
 378   ProductState state;
 379   return state.Initialize(system_install, dist) && state.is_multi_install();
 380 }
 381
 382 bool CheckIsChromeSxSProcess() {
 383   CommandLine* command_line = CommandLine::ForCurrentProcess();
 384   CHECK(command_line);
 385
 386   if (command_line->HasSwitch(installer::switches::kChromeSxS))
 387     return true;
 388
 389   // Also return true if we are running from Chrome SxS installed path.
 390   base::FilePath exe_dir;
 391   PathService::Get(base::DIR_EXE, &exe_dir);
 392   base::string16 chrome_sxs_dir(installer::kGoogleChromeInstallSubDir2);
 393   chrome_sxs_dir.append(installer::kSxSSuffix);
 394
 395   // This is SxS if current EXE is in or under (possibly multiple levels under)
 396   // |chrome_sxs_dir|\|installer::kInstallBinaryDir|
 397   std::vector<base::FilePath::StringType> components;
 398   exe_dir.GetComponents(&components);
 399   // We need at least 1 element in the array for the behavior of the following
 400   // loop to be defined.  This should always be true, since we're splitting the
 401   // path to our executable and one of the components will be the drive letter.
 402   DCHECK(!components.empty());
 403   typedef std::vector<base::FilePath::StringType>::const_reverse_iterator
 404       ComponentsIterator;
 405   for (ComponentsIterator current = components.rbegin(), parent = current + 1;
 406        parent != components.rend(); current = parent++) {
 407     if (base::FilePath::CompareEqualIgnoreCase(
 408             *current, installer::kInstallBinaryDir) &&
 409         base::FilePath::CompareEqualIgnoreCase(*parent, chrome_sxs_dir)) {
 410       return true;
 411     }
 412   }
 413
 414   return false;
 415 }
 416
 417 bool InstallUtil::IsChromeSxSProcess() {
 418   static bool sxs = CheckIsChromeSxSProcess();
 419   return sxs;
 420 }
 421
 422 // static
 423 bool InstallUtil::IsFirstRunSentinelPresent() {
 424   // TODO(msw): Consolidate with first_run::internal::IsFirstRunSentinelPresent.
 425   base::FilePath user_data_dir;
 426   return !PathService::Get(chrome::DIR_USER_DATA, &user_data_dir) ||
 427          base::PathExists(user_data_dir.Append(chrome::kFirstRunSentinel));
 428 }
 429
 430 // static
 431 bool InstallUtil::GetEULASentinelFilePath(base::FilePath* path) {
 432   base::FilePath user_data_dir;
 433   if (!PathService::Get(chrome::DIR_USER_DATA, &user_data_dir))
 434     return false;
 435   *path = user_data_dir.Append(installer::kEULASentinelFile);
 436   return true;
 437 }
 438
 439 // This method tries to delete a registry key and logs an error message
 440 // in case of failure. It returns true if deletion is successful (or the key did
 441 // not exist), otherwise false.
 442 bool InstallUtil::DeleteRegistryKey(HKEY root_key,
 443                                     const base::string16& key_path,
 444                                     REGSAM wow64_access) {
 445   VLOG(1) << "Deleting registry key " << key_path;
 446   RegKey target_key;
 447   LONG result = target_key.Open(root_key, key_path.c_str(),
 448                                 KEY_READ | KEY_WRITE | wow64_access);
 449
 450   if (result == ERROR_FILE_NOT_FOUND)
 451     return true;
 452
 453   if (result == ERROR_SUCCESS)
 454     result = target_key.DeleteKey(L"");
 455
 456   if (result != ERROR_SUCCESS) {
 457     LOG(ERROR) << "Failed to delete registry key: " << key_path
 458                << " error: " << result;
 459     return false;
 460   }
 461   return true;
 462 }
 463
 464 // This method tries to delete a registry value and logs an error message
 465 // in case of failure. It returns true if deletion is successful (or the key did
 466 // not exist), otherwise false.
 467 bool InstallUtil::DeleteRegistryValue(HKEY reg_root,
 468                                       const base::string16& key_path,
 469                                       REGSAM wow64_access,
 470                                       const base::string16& value_name) {
 471   RegKey key;
 472   LONG result = key.Open(reg_root, key_path.c_str(),
 473                          KEY_SET_VALUE | wow64_access);
 474   if (result == ERROR_SUCCESS)
 475     result = key.DeleteValue(value_name.c_str());
 476   if (result != ERROR_SUCCESS && result != ERROR_FILE_NOT_FOUND) {
 477     LOG(ERROR) << "Failed to delete registry value: " << value_name
 478                << " error: " << result;
 479     return false;
 480   }
 481   return true;
 482 }
 483
 484 // static
 485 InstallUtil::ConditionalDeleteResult InstallUtil::DeleteRegistryKeyIf(
 486     HKEY root_key,
 487     const base::string16& key_to_delete_path,
 488     const base::string16& key_to_test_path,
 489     const REGSAM wow64_access,
 490     const wchar_t* value_name,
 491     const RegistryValuePredicate& predicate) {
 492   DCHECK(root_key);
 493   ConditionalDeleteResult delete_result = NOT_FOUND;
 494   RegKey key;
 495   base::string16 actual_value;
 496   if (key.Open(root_key, key_to_test_path.c_str(),
 497                KEY_QUERY_VALUE | wow64_access) == ERROR_SUCCESS &&
 498       key.ReadValue(value_name, &actual_value) == ERROR_SUCCESS &&
 499       predicate.Evaluate(actual_value)) {
 500     key.Close();
 501     delete_result = DeleteRegistryKey(root_key,
 502                                       key_to_delete_path,
 503                                       wow64_access)
 504         ? DELETED : DELETE_FAILED;
 505   }
 506   return delete_result;
 507 }
 508
 509 // static
 510 InstallUtil::ConditionalDeleteResult InstallUtil::DeleteRegistryValueIf(
 511     HKEY root_key,
 512     const wchar_t* key_path,
 513     REGSAM wow64_access,
 514     const wchar_t* value_name,
 515     const RegistryValuePredicate& predicate) {
 516   DCHECK(root_key);
 517   DCHECK(key_path);
 518   ConditionalDeleteResult delete_result = NOT_FOUND;
 519   RegKey key;
 520   base::string16 actual_value;
 521   if (key.Open(root_key, key_path,
 522                KEY_QUERY_VALUE | KEY_SET_VALUE | wow64_access)
 523           == ERROR_SUCCESS &&
 524       key.ReadValue(value_name, &actual_value) == ERROR_SUCCESS &&
 525       predicate.Evaluate(actual_value)) {
 526     LONG result = key.DeleteValue(value_name);
 527     if (result != ERROR_SUCCESS) {
 528       LOG(ERROR) << "Failed to delete registry value: "
 529                  << (value_name ? value_name : L"(Default)")
 530                  << " error: " << result;
 531       delete_result = DELETE_FAILED;
 532     }
 533     delete_result = DELETED;
 534   }
 535   return delete_result;
 536 }
 537
 538 bool InstallUtil::ValueEquals::Evaluate(const base::string16& value) const {
 539   return value == value_to_match_;
 540 }
 541
 542 // static
 543 int InstallUtil::GetInstallReturnCode(installer::InstallStatus status) {
 544   switch (status) {
 545     case installer::FIRST_INSTALL_SUCCESS:
 546     case installer::INSTALL_REPAIRED:
 547     case installer::NEW_VERSION_UPDATED:
 548     case installer::IN_USE_UPDATED:
 549     case installer::UNUSED_BINARIES_UNINSTALLED:
 550       return 0;
 551     default:
 552       return status;
 553   }
 554 }
 555
 556 // static
 557 void InstallUtil::MakeUninstallCommand(const base::string16& program,
 558                                        const base::string16& arguments,
 559                                        CommandLine* command_line) {
 560   *command_line = CommandLine::FromString(L"\"" + program + L"\" " + arguments);
 561 }
 562
 563 // static
 564 base::string16 InstallUtil::GetCurrentDate() {
 565   static const wchar_t kDateFormat[] = L"yyyyMMdd";
 566   wchar_t date_str[arraysize(kDateFormat)] = {0};
 567   int len = GetDateFormatW(LOCALE_INVARIANT, 0, NULL, kDateFormat,
 568                            date_str, arraysize(date_str));
 569   if (len) {
 570     --len;  // Subtract terminating \0.
 571   } else {
 572     PLOG(DFATAL) << "GetDateFormat";
 573   }
 574
 575   return base::string16(date_str, len);
 576 }
 577
 578 // Open |path| with minimal access to obtain information about it, returning
 579 // true and populating |file| on success.
 580 // static
 581 bool InstallUtil::ProgramCompare::OpenForInfo(const base::FilePath& path,
 582                                               base::File* file) {
 583   DCHECK(file);
 584   file->Initialize(path, base::File::FLAG_OPEN);
 585   return file->IsValid();
 586 }
 587
 588 // Populate |info| for |file|, returning true on success.
 589 // static
 590 bool InstallUtil::ProgramCompare::GetInfo(const base::File& file,
 591                                           BY_HANDLE_FILE_INFORMATION* info) {
 592   DCHECK(file.IsValid());
 593   return GetFileInformationByHandle(file.GetPlatformFile(), info) != 0;
 594 }
 595
 596 InstallUtil::ProgramCompare::ProgramCompare(const base::FilePath& path_to_match)
 597     : path_to_match_(path_to_match),
 598       file_info_() {
 599   DCHECK(!path_to_match_.empty());
 600   if (!OpenForInfo(path_to_match_, &file_)) {
 601     PLOG(WARNING) << "Failed opening " << path_to_match_.value()
 602                   << "; falling back to path string comparisons.";
 603   } else if (!GetInfo(file_, &file_info_)) {
 604     PLOG(WARNING) << "Failed getting information for "
 605                   << path_to_match_.value()
 606                   << "; falling back to path string comparisons.";
 607     file_.Close();
 608   }
 609 }
 610
 611 InstallUtil::ProgramCompare::~ProgramCompare() {
 612 }
 613
 614 bool InstallUtil::ProgramCompare::Evaluate(const base::string16& value) const {
 615   // Suss out the exe portion of the value, which is expected to be a command
 616   // line kinda (or exactly) like:
 617   // "c:\foo\bar\chrome.exe" -- "%1"
 618   base::FilePath program(CommandLine::FromString(value).GetProgram());
 619   if (program.empty()) {
 620     LOG(WARNING) << "Failed to parse an executable name from command line: \""
 621                  << value << "\"";
 622     return false;
 623   }
 624
 625   return EvaluatePath(program);
 626 }
 627
 628 bool InstallUtil::ProgramCompare::EvaluatePath(
 629     const base::FilePath& path) const {
 630   // Try the simple thing first: do the paths happen to match?
 631   if (base::FilePath::CompareEqualIgnoreCase(path_to_match_.value(),
 632                                              path.value()))
 633     return true;
 634
 635   // If the paths don't match and we couldn't open the expected file, we've done
 636   // our best.
 637   if (!file_.IsValid())
 638     return false;
 639
 640   // Open the program and see if it references the expected file.
 641   base::File file;
 642   BY_HANDLE_FILE_INFORMATION info = {};
 643
 644   return (OpenForInfo(path, &file) &&
 645           GetInfo(file, &info) &&
 646           info.dwVolumeSerialNumber == file_info_.dwVolumeSerialNumber &&
 647           info.nFileIndexHigh == file_info_.nFileIndexHigh &&
 648           info.nFileIndexLow == file_info_.nFileIndexLow);
 649 }