Fix registerProtocolHandler implementation on Windows 8 and 10.

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"
@@ skipping 62 matching lines @@
   // Defaut Programs). These registrations can be in HKCU as of Windows 8.
   // Note: Shell registration implies ProgId registration.
   CONFIRM_SHELL_REGISTRATION,
   // Same as CONFIRM_SHELL_REGISTRATION, but only look in HKLM (used when
   // uninstalling to know whether elevation is required to clean up the
   // registry).
   CONFIRM_SHELL_REGISTRATION_IN_HKLM,
 };
 
 const wchar_t kReinstallCommand[] = L"ReinstallCommand";
+const wchar_t kSystemSettingsDefaultAppsFormat[] =
+    L"SystemSettings_DefaultApps_%ls";
 
 // Returns the current (or installed) browser's ProgId (e.g.
 // "ChromeHTML|suffix|").
 // |suffix| can be the empty string.
 base::string16 GetBrowserProgId(const base::string16& suffix) {
   BrowserDistribution* dist = BrowserDistribution::GetDistribution();
   base::string16 chrome_html(dist->GetBrowserProgIdPrefix());
   chrome_html.append(suffix);
 
   // ProgIds cannot be longer than 39 characters.
@@ skipping 609 matching lines @@
     DWORD ret_val = 0;
     InstallUtil::ExecuteExeAsAdmin(cmd, &ret_val);
     if (ret_val == 0)
       return true;
   }
   return false;
 }
 
 // Launches the Windows 'settings' modern app with the 'default apps' view
 // focused. This only works for Windows 8 and Windows 10. The appModelId
-// looks arbitrary but it is the same in Win8 and Win10 previews. There
-// is no easy way to retrieve the appModelId from the registry.
-bool LaunchDefaultAppsSettingsModernDialog() {
+// looks arbitrary but it is the same in Win8 and Win10. There is no easy way to
+// retrieve the appModelId from the registry.
+bool LaunchDefaultAppsSettingsModernDialog(const wchar_t* target) {

[grt (UTC plus 2), 2016/04/15 18:47:26]

how about having this take the protocol rather than a target? it can take care
of the mapping of http and mailto to specific targets.

[Patrick Monette, 2016/04/15 21:35:42]

Done.

+  DCHECK(target);
+  static const wchar_t kControlPanelAppModelId[] =
+      L"windows.immersivecontrolpanel_cw5n1h2txyewy"
+      L"!microsoft.windows.immersivecontrolpanel";
+
   base::win::ScopedComPtr<IApplicationActivationManager> activator;
   HRESULT hr = activator.CreateInstance(CLSID_ApplicationActivationManager);
   if (SUCCEEDED(hr)) {
     DWORD pid = 0;
     CoAllowSetForegroundWindow(activator.get(), nullptr);
-    hr = activator->ActivateApplication(
-        L"windows.immersivecontrolpanel_cw5n1h2txyewy"
-        L"!microsoft.windows.immersivecontrolpanel",
-        L"page=SettingsPageAppsDefaults", AO_NONE, &pid);
+    hr = activator->ActivateApplication(kControlPanelAppModelId,
+                                        L"page=SettingsPageAppsDefaults",
+                                        AO_NONE, &pid);
     if (SUCCEEDED(hr)) {
       hr = activator->ActivateApplication(
-          L"windows.immersivecontrolpanel_cw5n1h2txyewy"
-          L"!microsoft.windows.immersivecontrolpanel",
-          L"page=SettingsPageAppsDefaults"
-          L"&target=SystemSettings_DefaultApps_Browser", AO_NONE, &pid);
+          kControlPanelAppModelId,
+          base::StringPrintf(L"page=SettingsPageAppsDefaults&target=%ls",
+                             target)
+              .c_str(),
+          AO_NONE, &pid);
     }
     if (SUCCEEDED(hr))
       return true;
     UMA_HISTOGRAM_SPARSE_SLOWLY("DefaultBrowser.ActivateSettings.ErrorHresult",
                                 hr);
   }
   return false;
 }
 
 // Launches the Windows 7 and Windows 8 dialog for picking the application to
@@ skipping 596 matching lines @@
     return false;
   }
   if (base::IsDirectoryEmpty(shortcut_folder) &&
       !base::DeleteFile(shortcut_folder, true)) {
     LOG(ERROR) << "Cannot remove folder " << shortcut_folder.value();
     return false;
   }
   return true;
 }
 
+// Returns the target used as a activate parameter when opening the settings
+// pointing to the page that is the most relevant to a user trying to change the
+// default handler for |protocol|.
+base::string16 GetTargetForDefaultAppsSettings(const base::string16& protocol) {
+  if (protocol == L"mailto")
+    return base::StringPrintf(kSystemSettingsDefaultAppsFormat, L"Email");
+
+  return L"SettingsPageAppsDefaultsProtocolView";
+}
+
+// Creates the registry key <root hkey>\Software\Classes\<protocol>\URL Protocol
+// so that Windows allows the handler for this |protocol| to be be changed.
+bool CreateKeyForProtocol(const wchar_t* protocol) {
+  RegKey reg_key(HKEY_CURRENT_USER, ShellUtil::kRegClasses, KEY_ALL_ACCESS);
+  DCHECK(reg_key.Valid());
+  if (reg_key.CreateKey(protocol, KEY_CREATE_SUB_KEY | KEY_SET_VALUE) !=
+      ERROR_SUCCESS)
+    return false;
+
+  return reg_key.WriteValue(ShellUtil::kRegUrlProtocol, L"") == ERROR_SUCCESS;
+}
+
 }  // 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 452 matching lines @@
   return ProbeProtocolHandlers(chrome_exe,
                                protocols,
                                arraysize(protocols));
 }
 
 // static
 bool ShellUtil::CanMakeChromeDefaultUnattended() {
   return base::win::GetVersion() < base::win::VERSION_WIN8;
 }
 
+// static
+ShellUtil::SetDefaultInteractiveMode ShellUtil::GetSetDefaultInteractiveMode() {
+  DCHECK(!CanMakeChromeDefaultUnattended());
+
+  if (base::win::GetVersion() == base::win::VERSION_WIN8) {

[grt (UTC plus 2), 2016/04/15 18:47:26]

nit: omit braces

[Patrick Monette, 2016/04/15 21:35:42]

Done.

+    return SetDefaultInteractiveMode::INTENT_PICKER;
+  }
+
+  return SetDefaultInteractiveMode::SYSTEM_SETTINGS;
+}
+
 bool ShellUtil::MakeChromeDefault(BrowserDistribution* dist,
                                   int shell_change,
                                   const base::FilePath& chrome_exe,
                                   bool elevate_if_not_admin) {
   DCHECK(!(shell_change & SYSTEM_LEVEL) || IsUserAnAdmin());
 
   BrowserDistribution* distribution = BrowserDistribution::GetDistribution();
   if (distribution->GetDefaultBrowserControlPolicy() !=
       BrowserDistribution::DEFAULT_BROWSER_FULL_CONTROL) {
     return false;
@@ skipping 53 matching lines @@
 
   // Send Windows notification event so that it can update icons for
   // file associations.
   SHChangeNotify(SHCNE_ASSOCCHANGED, SHCNF_IDLIST, NULL, NULL);
   return ret;
 }
 
 bool ShellUtil::ShowMakeChromeDefaultSystemUI(
     BrowserDistribution* dist,
     const base::FilePath& chrome_exe) {
-  DCHECK_GE(base::win::GetVersion(), base::win::VERSION_WIN8);
+  DCHECK(!CanMakeChromeDefaultUnattended());
   if (dist->GetDefaultBrowserControlPolicy() !=
       BrowserDistribution::DEFAULT_BROWSER_FULL_CONTROL) {
     return false;
   }
 
   if (!RegisterChromeBrowser(dist, chrome_exe, base::string16(), true))
       return false;
 
   bool succeeded = true;
   bool is_default = (GetChromeDefaultState() == IS_DEFAULT);
   if (!is_default) {
-    if (base::win::GetVersion() < base::win::VERSION_WIN10) {
-      // On Windows 8, you can't set yourself as the default handler
-      // programatically. In other words IApplicationAssociationRegistration
-      // has been rendered useless. What you can do is to launch
-      // "Set Program Associations" section of the "Default Programs"
-      // control panel, which is a mess, or pop the concise "How you want to
-      // open webpages?" dialog.  We choose the latter.
-      ScopedUserProtocolEntry user_protocol_entry;
-      succeeded = LaunchSelectDefaultProtocolHandlerDialog(L"http");
-    } else {
-      // On Windows 10, you can't even launch the associations dialog.
-      // So we launch the settings dialog. Quoting from MSDN: "The Open With
-      // dialog box can no longer be used to change the default program used to
-      // open a file extension. You can only use SHOpenWithDialog to open
-      // a single file."
-      succeeded = LaunchDefaultAppsSettingsModernDialog();
+    switch (GetSetDefaultInteractiveMode()) {
+      case INTENT_PICKER: {
+        // On Windows 8, you can't set yourself as the default handler
+        // programatically. In other words IApplicationAssociationRegistration
+        // has been rendered useless. What you can do is to launch
+        // "Set Program Associations" section of the "Default Programs"
+        // control panel, which is a mess, or pop the concise "How you want to
+        // open webpages?" dialog.  We choose the latter.
+        ScopedUserProtocolEntry user_protocol_entry;
+        succeeded = LaunchSelectDefaultProtocolHandlerDialog(L"http");
+      } break;

[grt (UTC plus 2), 2016/04/15 18:47:26]

is this what git cl format likes?

[Patrick Monette, 2016/04/15 21:35:42]

Yes.

+      case SYSTEM_SETTINGS:
+        // On Windows 10, you can't even launch the associations dialog.
+        // So we launch the settings dialog. Quoting from MSDN: "The Open With
+        // dialog box can no longer be used to change the default program used
+        // to open a file extension. You can only use SHOpenWithDialog to open
+        // a single file."
+        succeeded = LaunchDefaultAppsSettingsModernDialog(
+            base::StringPrintf(kSystemSettingsDefaultAppsFormat, L"Browser")

[grt (UTC plus 2), 2016/04/15 18:47:26]

how about using GetTargetForDefaultAppsSettings(L"http") for this? as a benefit,
kSystemSettingsDefaultAppsFormat can be moved into the function.

[Patrick Monette, 2016/04/15 21:35:42]

Done.

+                .c_str());
+        break;
     }
     is_default = (succeeded && GetChromeDefaultState() == IS_DEFAULT);
   }
   if (succeeded && is_default)
     RegisterChromeAsDefaultXPStyle(dist, CURRENT_USER, chrome_exe);
   return succeeded;
 }
 
 bool ShellUtil::MakeChromeDefaultProtocolClient(
     BrowserDistribution* dist,
@@ skipping 41 matching lines @@
   if (!RegisterChromeAsDefaultProtocolClientXPStyle(dist, chrome_exe, protocol))
     ret = false;
 
   return ret;
 }
 
 bool ShellUtil::ShowMakeChromeDefaultProtocolClientSystemUI(
     BrowserDistribution* dist,
     const base::FilePath& chrome_exe,
     const base::string16& protocol) {
-  DCHECK_GE(base::win::GetVersion(), base::win::VERSION_WIN8);
+  DCHECK(!CanMakeChromeDefaultUnattended());
   if (dist->GetDefaultBrowserControlPolicy() !=
       BrowserDistribution::DEFAULT_BROWSER_FULL_CONTROL) {
     return false;
   }
 
   if (!RegisterChromeForProtocol(
            dist, chrome_exe, base::string16(), protocol, true))
     return false;
 
+  // This registry key is required so Windows give the user the possibility to
+  // choose a default handler for |protocol|.
+  if (!CreateKeyForProtocol(protocol.c_str())) {

[grt (UTC plus 2), 2016/04/15 18:47:26]

is this doing the same thing that the ScopedUserProtocolEntry does? can you
generalize that and use it here?

[Patrick Monette, 2016/04/15 21:35:42]

Good point! I generalized it for all protocols so I can use it for the win8 path
here. For the win10 path, the better scope is the OpenSystemSettingsHelper so I
moved it there.

+    DVLOG(1) << "Failed to create a valid key for the protocol " << protocol;
+    return false;
+  }
+
   bool succeeded = true;
   bool is_default = (
       GetChromeDefaultProtocolClientState(protocol) == IS_DEFAULT);
   if (!is_default) {
-    // On Windows 8, you can't set yourself as the default handler
-    // programatically. In other words IApplicationAssociationRegistration
-    // has been rendered useless. What you can do is to launch
-    // "Set Program Associations" section of the "Default Programs"
-    // control panel, which is a mess, or pop the concise "How you want to open
-    // links of this type (protocol)?" dialog.  We choose the latter.
-    succeeded = LaunchSelectDefaultProtocolHandlerDialog(protocol.c_str());
+    switch (GetSetDefaultInteractiveMode()) {
+      case INTENT_PICKER: {
+        // On Windows 8, you can't set yourself as the default handler
+        // programatically. In other words IApplicationAssociationRegistration
+        // has been rendered useless. What you can do is to launch
+        // "Set Program Associations" section of the "Default Programs"
+        // control panel, which is a mess, or pop the concise "How you want to
+        // open
+        // links of this type (protocol)?" dialog.  We choose the latter.
+        ScopedUserProtocolEntry user_protocol_entry;

[grt (UTC plus 2), 2016/04/15 18:47:26]

as-is, this is specifically for http, so it isn't needed here, unless it's
suitable to be generalized as per my comment above.

[Patrick Monette, 2016/04/15 21:35:41]

Done.

+        succeeded = LaunchSelectDefaultProtocolHandlerDialog(protocol.c_str());
+      } break;
+      case SYSTEM_SETTINGS:
+        // On Windows 10, you can't even launch the associations dialog.
+        // So we launch the settings dialog.
+        succeeded = LaunchDefaultAppsSettingsModernDialog(
+            GetTargetForDefaultAppsSettings(protocol).c_str());
+        break;
+    }
     is_default = (succeeded &&
                   GetChromeDefaultProtocolClientState(protocol) == IS_DEFAULT);
   }
   if (succeeded && is_default)
     RegisterChromeAsDefaultProtocolClientXPStyle(dist, chrome_exe, protocol);
   return succeeded;
 }
 
 bool ShellUtil::RegisterChromeBrowser(BrowserDistribution* dist,
                                       const base::FilePath& chrome_exe,
@@ skipping 329 matching lines @@
        itr != entries.end(); ++itr)
     (*itr)->AddToWorkItemList(root, items.get());
 
   // Apply all the registry changes and if there is a problem, rollback
   if (!items->Do()) {
     items->Rollback();
     return false;
   }
   return true;
 }