Refactoring installer shortcut deletion; adding dedicated shortcut update feature.

chrome/installer/util/shell_util.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file defines functions that integrate Chrome in Windows shell. These
 // functions can be used by Chrome as well as Chrome installer. All of the
 // work is done by the local functions defined in anonymous namespace in
 // this class.
 
 #include "chrome/installer/util/shell_util.h"
 
 #include <windows.h>
 #include <shlobj.h>
 
 #include <limits>
 #include <string>
 
+#include "base/bind.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/md5.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/path_service.h"
 #include "base/string16.h"
@@ skipping 1124 matching lines @@
   const base::win::Version windows_version = base::win::GetVersion();
 
   if (windows_version >= base::win::VERSION_WIN8)
     return ProbeCurrentDefaultHandlers(protocols, num_protocols);
   else if (windows_version >= base::win::VERSION_VISTA)
     return ProbeAppIsDefaultHandlers(protocols, num_protocols);
 
   return ProbeOpenCommandHandlers(protocols, num_protocols);
 }
 
-// Removes shortcut at |shortcut_path| if it is a shortcut that points to
-// |target_exe|. If |delete_folder| is true, deletes the parent folder of
-// the shortcut completely. Returns true if either the shortcut was deleted
-// successfully or if the shortcut did not point to |target_exe|.
-bool MaybeRemoveShortcutAtPath(const base::FilePath& shortcut_path,
-                               const base::FilePath& target_exe,
-                               bool delete_folder) {
-  base::FilePath target_path;
-  if (!base::win::ResolveShortcut(shortcut_path, &target_path, NULL))
+// (Windows 8+) Finds and stores an app shortcuts folder path in *|path|.
+// Returns true on success.
+bool GetAppShortcutsFolder(BrowserDistribution* dist,
+                           ShellUtil::ShellChange level,
+                           base::FilePath *path) {
+  DCHECK(path);
+  DCHECK(base::win::GetVersion() >= base::win::VERSION_WIN8);

[grt (UTC plus 2), 2013/05/01 16:33:43]

DCHECK_GE

[huangs, 2013/05/01 17:42:09]

Done.

+
+  base::FilePath folder;
+  if (!PathService::Get(base::DIR_APP_SHORTCUTS, &folder)) {
+    LOG(ERROR) << "Could not get application shortcuts location.";
     return false;
-
-  if (InstallUtil::ProgramCompare(target_exe).EvaluatePath(target_path)) {
-    // Unpin the shortcut if it was ever pinned by the user or the installer.
-    VLOG(1) << "Trying to unpin " << shortcut_path.value();
-    if (!base::win::TaskbarUnpinShortcutLink(shortcut_path.value().c_str())) {
-      VLOG(1) << shortcut_path.value()
-              << " wasn't pinned (or the unpin failed).";
-    }
-    if (delete_folder)
-      return file_util::Delete(shortcut_path.DirName(), true);
-    else
-      return file_util::Delete(shortcut_path, false);
   }
 
-  // The shortcut at |shortcut_path| doesn't point to |target_exe|, act as if
-  // our shortcut had been deleted.
+  folder = folder.Append(
+      ShellUtil::GetBrowserModelId(dist, level == ShellUtil::CURRENT_USER));
+  if (!file_util::DirectoryExists(folder)) {
+    VLOG(1) << "No start screen shortcuts.";
+    return false;
+  }
+
+  *path = folder;
   return true;
 }
 
+typedef base::Callback<bool(const base::FilePath&)> FileOperationCallback;
+
+// Shortcut operations for BatchShortcutAction().
+
+bool ShortcutOpUnpin(const base::FilePath& shortcut_path) {
+  VLOG(1) << "Trying to unpin " << shortcut_path.value();
+  if (!base::win::TaskbarUnpinShortcutLink(shortcut_path.value().c_str())) {
+    VLOG(1) << shortcut_path.value() << " wasn't pinned (or the unpin failed).";
+    // No error, since shortcut might not be pinned.
+  }
+  return true;
+}
+
+bool ShortcutOpDelete(const base::FilePath& shortcut_path) {
+  bool ret = file_util::Delete(shortcut_path, false);
+  LOG_IF(ERROR, !ret) << "Failed to remove " << shortcut_path.value();
+  return ret;
+}
+
+bool ShortcutOpSetTarget(const base::FilePath& target_path,
+                         const base::FilePath& shortcut_path) {
+  base::win::ShortcutProperties shortcut_properties;
+  shortcut_properties.set_target(target_path);
+  shortcut_properties.set_working_dir(target_path.DirName());
+  bool ret = base::win::CreateOrUpdateShortcutLink(
+      shortcut_path, shortcut_properties, base::win::SHORTCUT_REPLACE_EXISTING);
+  LOG_IF(ERROR, !ret) << "Failed to retarget " << shortcut_path.value();
+  return ret;
+}
+
+// {|location|, |dist|, |level|} determine |shortcut_folder|.
+// Applies |shortcut_operation| to each shortcut in |shortcut_folder| that
+// targets |target_exe|.
+// Returns true if all operations are successful. All intended operations are
+// attempted even if failures occur.
+bool BatchShortcutAction(const FileOperationCallback& shortcut_operation,
+                         ShellUtil::ShortcutLocation location,
+                         BrowserDistribution* dist,
+                         ShellUtil::ShellChange level,
+                         const base::FilePath& target_exe) {
+  DCHECK(!shortcut_operation.is_null());
+  base::FilePath shortcut_folder;
+  if (!ShellUtil::GetShortcutPath(location, dist, level, &shortcut_folder)) {
+    LOG(WARNING) << "Cannot find path at location " << location;
+    return false;
+  }
+
+  bool success = true;
+  InstallUtil::ProgramCompare target_compare(target_exe);
+  file_util::FileEnumerator enumerator(
+      shortcut_folder, false, file_util::FileEnumerator::FILES,
+      string16(L"*") + installer::kLnkExt);
+  base::FilePath target_path;
+  for (base::FilePath shortcut_path = enumerator.Next();
+       !shortcut_path.empty();
+       shortcut_path = enumerator.Next()) {
+    if (base::win::ResolveShortcut(shortcut_path, &target_path, NULL)) {
+      if (target_compare.EvaluatePath(target_path) &&
+          !shortcut_operation.Run(shortcut_path)) {
+        success = false;
+      }
+    } else {
+      LOG(ERROR) << "Cannot resolve shortcut at " << shortcut_path.value();
+      success = false;
+    }
+  }
+  return success;
+}
+
+// Removes folder spsecified by {|location|, |dist|, |level|}.
+bool RemoveShortcutFolder(ShellUtil::ShortcutLocation location,

[grt (UTC plus 2), 2013/05/01 16:33:43]

please explicitly whitelist the |location| values for which this function is
valid. as it is, an accidental call to this with something like
SHORTCUT_LOCATION_DESKTOP would be very bad.

[huangs, 2013/05/01 17:42:09]

Done.

+                          BrowserDistribution* dist,
+                          ShellUtil::ShellChange level) {
+  base::FilePath shortcut_folder;
+  if (!ShellUtil::GetShortcutPath(location, dist, level, &shortcut_folder)) {
+    LOG(WARNING) << "Cannot find path at location " << location;
+    return false;
+  }
+  if (!file_util::Delete(shortcut_folder, true)) {
+    LOG(ERROR) << "Cannot remove folder " << shortcut_folder.value();
+    return false;
+  }
+  return true;
+}
+
 }  // namespace
 
 const wchar_t* ShellUtil::kRegDefaultIcon = L"\\DefaultIcon";
 const wchar_t* ShellUtil::kRegShellPath = L"\\shell";
 const wchar_t* ShellUtil::kRegShellOpen = L"\\shell\\open\\command";
 const wchar_t* ShellUtil::kRegStartMenuInternet =
     L"Software\\Clients\\StartMenuInternet";
 const wchar_t* ShellUtil::kRegClasses = L"Software\\Classes";
 const wchar_t* ShellUtil::kRegRegisteredApplications =
     L"Software\\RegisteredApplications";
@@ skipping 42 matching lines @@
 const wchar_t* ShellUtil::kRegDelegateExecute = L"DelegateExecute";
 const wchar_t* ShellUtil::kRegOpenWithProgids = L"OpenWithProgids";
 
 bool ShellUtil::QuickIsChromeRegisteredInHKLM(BrowserDistribution* dist,
                                               const string16& chrome_exe,
                                               const string16& suffix) {
   return QuickIsChromeRegistered(dist, chrome_exe, suffix,
                                  CONFIRM_SHELL_REGISTRATION_IN_HKLM);
 }
 
+bool ShellUtil::ShortcutLocationIsExpected(

[grt (UTC plus 2), 2013/05/01 16:33:43]

Expected -> Supported

[huangs, 2013/05/01 17:42:09]

Done.

+    ShellUtil::ShortcutLocation location) {
+  switch (location) {
+    case SHORTCUT_LOCATION_DESKTOP:
+      return true;
+    case SHORTCUT_LOCATION_QUICK_LAUNCH:
+      return true;
+    case SHORTCUT_LOCATION_START_MENU:
+      return base::win::GetVersion() < base::win::VERSION_WIN8;

[grt (UTC plus 2), 2013/05/01 16:33:43]

why?

[huangs, 2013/05/01 17:42:09]

I thought Windows 8 does not have a Start Menu? Unless it's used for something
else. Since I'm not an expert, removing.

[gab, 2013/05/01 18:34:42]

The Windows 8 start screen replaces the start menu, but uses the same shortcut
folder and we treat it the same in the installer.

[huangs, 2013/05/01 19:22:22]

Ah, good to know. Fortunately I removed, so no extra code change necessary.  :)

+    case SHORTCUT_LOCATION_TASKBAR_PINS:
+      return base::win::GetVersion() >= base::win::VERSION_WIN7;
+    case SHORTCUT_LOCATION_APP_SHORTCUTS:
+      return base::win::GetVersion() >= base::win::VERSION_WIN8;
+    default:
+      NOTREACHED();
+      return false;
+  }
+}
+
 bool ShellUtil::GetShortcutPath(ShellUtil::ShortcutLocation location,
                                 BrowserDistribution* dist,
                                 ShellChange level,
                                 base::FilePath* path) {
+  DCHECK(path);
   int dir_key = -1;
   bool add_folder_for_dist = false;
   switch (location) {
     case SHORTCUT_LOCATION_DESKTOP:
       dir_key = (level == CURRENT_USER) ? base::DIR_USER_DESKTOP :
                                           base::DIR_COMMON_DESKTOP;
       break;
     case SHORTCUT_LOCATION_QUICK_LAUNCH:
       dir_key = (level == CURRENT_USER) ? base::DIR_USER_QUICK_LAUNCH :
                                           base::DIR_DEFAULT_USER_QUICK_LAUNCH;
       break;
     case SHORTCUT_LOCATION_START_MENU:
       dir_key = (level == CURRENT_USER) ? base::DIR_START_MENU :
                                           base::DIR_COMMON_START_MENU;
       add_folder_for_dist = true;
       break;
+    case SHORTCUT_LOCATION_TASKBAR_PINS:
+      dir_key = base::DIR_TASKBAR_PINS;
+      break;
+    case SHORTCUT_LOCATION_APP_SHORTCUTS:
+      return GetAppShortcutsFolder(dist, level, path);
+
     default:
       NOTREACHED();
       return false;
   }
 
   if (!PathService::Get(dir_key, path) || path->empty()) {
     NOTREACHED() << dir_key;
     return false;
   }
 
   if (add_folder_for_dist)
     *path = path->Append(dist->GetAppShortCutName());
 
   return true;
 }
 
 bool ShellUtil::CreateOrUpdateShortcut(
     ShellUtil::ShortcutLocation location,

[grt (UTC plus 2), 2013/05/01 16:33:43]

what does it mean to call this function with location ==
SHORTCUT_LOCATION_TASKBAR_PINS? should that not be prohibited?

[huangs, 2013/05/01 17:42:09]

Oops, I was going to abandon the call to ShortcutLocationIsSupported().

Meanwhile, adding explicit whitelist again, to preserve old behaviour (since I
added SHORTCUT_LOCATION_TASKBAR_PINS and SHORTCUT_LOCATION_APP_SHORTCUTS).

     BrowserDistribution* dist,
     const ShellUtil::ShortcutProperties& properties,
     ShellUtil::ShortcutOperation operation) {
+  if (!ShortcutLocationIsExpected(location))
+    return false;
+
   DCHECK(dist);
   // |pin_to_taskbar| is only acknowledged when first creating the shortcut.
   DCHECK(!properties.pin_to_taskbar ||
          operation == SHELL_SHORTCUT_CREATE_ALWAYS ||
          operation == SHELL_SHORTCUT_CREATE_IF_NO_SYSTEM_LEVEL);
 
   base::FilePath user_shortcut_path;
   base::FilePath system_shortcut_path;
-  if (!GetShortcutPath(location, dist, SYSTEM_LEVEL, &system_shortcut_path) ||
-      system_shortcut_path.empty()) {
-    NOTREACHED();
+  if (!GetShortcutPath(location, dist, SYSTEM_LEVEL, &system_shortcut_path))
     return false;
-  }
 
   string16 shortcut_name(ExtractShortcutNameFromProperties(dist, properties));
   system_shortcut_path = system_shortcut_path.Append(shortcut_name);
 
   base::FilePath* chosen_path;
   bool should_install_shortcut = true;
   if (properties.level == SYSTEM_LEVEL) {
     // Install the system-level shortcut if requested.
     chosen_path = &system_shortcut_path;
   } else if (operation != SHELL_SHORTCUT_CREATE_IF_NO_SYSTEM_LEVEL ||
              !file_util::PathExists(system_shortcut_path)) {
     // Otherwise install the user-level shortcut, unless the system-level
     // variant of this shortcut is present on the machine and |operation| states
     // not to create a user-level shortcut in that case.
-    if (!GetShortcutPath(location, dist, CURRENT_USER, &user_shortcut_path) ||
-        user_shortcut_path.empty()) {
+    if (!GetShortcutPath(location, dist, CURRENT_USER, &user_shortcut_path)) {
       NOTREACHED();
       return false;
     }
     user_shortcut_path = user_shortcut_path.Append(shortcut_name);
     chosen_path = &user_shortcut_path;
   } else {
     // Do not install any shortcut if we are told to install a user-level
     // shortcut, but the system-level variant of that shortcut is present.
     // Other actions (e.g., pinning) can still happen with respect to the
     // existing system-level shortcut however.
@@ skipping 518 matching lines @@
   } else if (elevate_if_not_admin &&
              base::win::GetVersion() >= base::win::VERSION_VISTA) {
     // Elevate to do the whole job
     return ElevateAndRegisterChrome(dist, chrome_exe, suffix, protocol);
   } else {
     // Admin rights are required to register capabilities before Windows 8.
     return false;
   }
 }
 
-bool ShellUtil::RemoveShortcut(ShellUtil::ShortcutLocation location,
-                               BrowserDistribution* dist,
-                               const base::FilePath& target_exe,
-                               ShellChange level,
-                               const string16* shortcut_name) {
-  const bool delete_folder = (location == SHORTCUT_LOCATION_START_MENU);
+// static
+bool ShellUtil::RemoveShortcuts(ShellUtil::ShortcutLocation location,
+                                BrowserDistribution* dist,
+                                ShellChange level,
+                                const base::FilePath& target_exe) {
+  if (!ShellUtil::ShortcutLocationIsExpected(location))
+    return true;  // Vacuous success.
 
-  base::FilePath shortcut_folder;
-  if (!GetShortcutPath(location, dist, level, &shortcut_folder) ||
-      shortcut_folder.empty()) {
-    NOTREACHED();
-    return false;
-  }
+  switch (location) {
+    case SHORTCUT_LOCATION_START_MENU:  // Falls through.
+    case SHORTCUT_LOCATION_APP_SHORTCUTS:
+      return RemoveShortcutFolder(location, dist, level);
 
-  if (!delete_folder && !shortcut_name) {
-    file_util::FileEnumerator enumerator(shortcut_folder, false,
-        file_util::FileEnumerator::FILES);
-    bool had_failures = false;
-    for (base::FilePath path = enumerator.Next(); !path.empty();
-         path = enumerator.Next()) {
-      if (path.Extension() != installer::kLnkExt)
-        continue;
+    case SHORTCUT_LOCATION_TASKBAR_PINS:
+      return BatchShortcutAction(base::Bind(&ShortcutOpUnpin), location, dist,
+                                 level, target_exe);
 
-      if (!MaybeRemoveShortcutAtPath(path, target_exe, delete_folder))
-        had_failures = true;
-    }
-    return !had_failures;
-  }
-
-  const string16 shortcut_base_name(
-      (shortcut_name ? *shortcut_name : dist->GetAppShortCutName()) +
-      installer::kLnkExt);
-  const base::FilePath shortcut_path(
-      shortcut_folder.Append(shortcut_base_name));
-  if (!file_util::PathExists(shortcut_path))
-    return true;
-
-  return MaybeRemoveShortcutAtPath(shortcut_path, target_exe, delete_folder);
-}
-
-void ShellUtil::RemoveTaskbarShortcuts(const string16& target_exe) {
-  if (base::win::GetVersion() < base::win::VERSION_WIN7)
-    return;
-
-  base::FilePath taskbar_pins_path;
-  if (!PathService::Get(base::DIR_TASKBAR_PINS, &taskbar_pins_path) ||
-      !file_util::PathExists(taskbar_pins_path)) {
-    LOG(ERROR) << "Couldn't find path to taskbar pins.";
-    return;
-  }
-
-  file_util::FileEnumerator shortcuts_enum(
-      taskbar_pins_path, false,
-      file_util::FileEnumerator::FILES, FILE_PATH_LITERAL("*.lnk"));
-
-  base::FilePath target_path(target_exe);
-  InstallUtil::ProgramCompare target_compare(target_path);
-  for (base::FilePath shortcut_path = shortcuts_enum.Next();
-       !shortcut_path.empty();
-       shortcut_path = shortcuts_enum.Next()) {
-    base::FilePath read_target;
-    if (!base::win::ResolveShortcut(shortcut_path, &read_target, NULL)) {
-      LOG(ERROR) << "Couldn't resolve shortcut at " << shortcut_path.value();
-      continue;
-    }
-    if (target_compare.EvaluatePath(read_target)) {
-      // Unpin this shortcut if it points to |target_exe|.
-      base::win::TaskbarUnpinShortcutLink(shortcut_path.value().c_str());
-    }
+    default:
+      return BatchShortcutAction(base::Bind(&ShortcutOpDelete), location, dist,
+                                 level, target_exe);
   }
 }
 
-void ShellUtil::RemoveStartScreenShortcuts(BrowserDistribution* dist,
-                                           const string16& target_exe) {
-  if (base::win::GetVersion() < base::win::VERSION_WIN8)
-    return;
+// static
+bool ShellUtil::RetargetShortcuts(ShellUtil::ShortcutLocation location,
+                                  BrowserDistribution* dist,
+                                  ShellChange level,
+                                  const base::FilePath& old_target_exe,
+                                  const base::FilePath& new_target_exe) {
+  if (!ShellUtil::ShortcutLocationIsExpected(location))
+    return true;  // Vacuous success.
 
-  base::FilePath app_shortcuts_path;
-  if (!PathService::Get(base::DIR_APP_SHORTCUTS, &app_shortcuts_path)) {
-    LOG(ERROR) << "Could not get application shortcuts location to delete"
-               << " start screen shortcuts.";
-    return;
-  }
-
-  app_shortcuts_path = app_shortcuts_path.Append(
-      GetBrowserModelId(dist,
-                        InstallUtil::IsPerUserInstall(target_exe.c_str())));
-  if (!file_util::DirectoryExists(app_shortcuts_path)) {
-    VLOG(1) << "No start screen shortcuts to delete.";
-    return;
-  }
-
-  VLOG(1) << "Removing start screen shortcuts from "
-          << app_shortcuts_path.value();
-  if (!file_util::Delete(app_shortcuts_path, true)) {
-    LOG(ERROR) << "Failed to remove start screen shortcuts from "
-               << app_shortcuts_path.value();
-  }
+  return BatchShortcutAction(base::Bind(&ShortcutOpSetTarget, new_target_exe),
+                             location, dist, level, old_target_exe);
 }
 
 bool ShellUtil::GetUserSpecificRegistrySuffix(string16* suffix) {
   // Use a thread-safe cache for the user's suffix.
   static base::LazyInstance<UserSpecificRegistrySuffix>::Leaky suffix_instance =
       LAZY_INSTANCE_INITIALIZER;
   return suffix_instance.Get().GetSuffix(suffix);
 }
 
 bool ShellUtil::GetOldUserSpecificRegistrySuffix(string16* suffix) {
@@ skipping 49 matching lines @@
     // are any left...).
     if (free_bits >= 8 && next_byte_index < size) {
       free_bits -= 8;
       bit_stream += bytes[next_byte_index++] << free_bits;
     }
   }
 
   DCHECK_EQ(ret.length(), encoded_length);
   return ret;
 }