Implement installation of the Chrome App Host.

chrome/installer/mini_installer/mini_installer.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
 // mini_installer.exe is the first exe that is run when chrome is being
 // installed or upgraded. It is designed to be extremely small (~5KB with no
 // extra resources linked) and it has two main jobs:
 //   1) unpack the resources (possibly decompressing some)
 //   2) run the real installer (setup.exe) with appropriate flags.
 //
 // In order to be really small the app doesn't link against the CRT and
@@ skipping 140 matching lines @@
 // should try full installer next time. If the current installer works, this
 // flag is cleared by setup.exe at the end of install. The flag will by default
 // be written to HKCU, but if --system-level is included in the command line,
 // it will be written to HKLM instead.
 // TODO(grt): Write a unit test for this that uses registry virtualization.
 void SetInstallerFlags(const Configuration& configuration) {
   RegKey key;
   const REGSAM key_access = KEY_QUERY_VALUE | KEY_SET_VALUE;
   const HKEY root_key =
       configuration.is_system_level() ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
+  // This is ignored if multi-install is true.
   const wchar_t* app_guid =
       configuration.has_chrome_frame() ?
           google_update::kChromeFrameAppGuid :
           configuration.chrome_app_guid();
   StackString<128> value;
   LONG ret;
 
   // When multi_install is true, we are potentially:
   // 1. Performing a multi-install of some product(s) on a clean machine.
   //    Neither the product(s) nor the multi-installer will have a ClientState
@@ skipping 43 matching lines @@
 
     if (!StrEndsWith(value.get(), kFullInstallerSuffix) &&
         value.append(kFullInstallerSuffix)) {
       key.WriteValue(kApRegistryValueName, value.get());
     }
   }
 }
 
 // Gets the setup.exe path from Registry by looking the value of Uninstall
 // string.  |size| is measured in wchar_t units.
+bool GetSetupExePathForGuidFromRegistry(bool system_level,
+                                        const wchar_t* app_guid,
+                                        wchar_t* path,
+                                        size_t size) {
+  const HKEY root_key = system_level ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
+  RegKey key;
+  return OpenClientStateKey(root_key, app_guid, KEY_QUERY_VALUE, &key) &&
+      (key.ReadValue(kUninstallRegistryValueName, path, size) == ERROR_SUCCESS);
+}
+
+// Gets the setup.exe path from Registry by looking the value of Uninstall
+// string.  |size| is measured in wchar_t units.
 bool GetSetupExePathFromRegistry(const Configuration& configuration,
                                  wchar_t* path,
                                  size_t size) {
-  const HKEY root_key =
-      configuration.is_system_level() ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
-  RegKey key;
-  bool succeeded = false;
+  bool system_level = configuration.is_system_level();
 
   // If this is a multi install, first try looking in the binaries for the path.
-  if (configuration.is_multi_install() &&
-      OpenClientStateKey(root_key, google_update::kMultiInstallAppGuid,
-                         KEY_QUERY_VALUE, &key)) {
-    succeeded = (key.ReadValue(kUninstallRegistryValueName, path,
-                               size) == ERROR_SUCCESS);
+  if (configuration.is_multi_install() && GetSetupExePathForGuidFromRegistry(
+          system_level, google_update::kMultiInstallAppGuid, path, size)) {
+    return true;
   }
 
-  // Failing that, look in Chrome Frame's client state key --chrome-frame was
+  // Failing that, look in Chrome Frame's client state key if --chrome-frame was
   // specified.
-  if (!succeeded && configuration.has_chrome_frame() &&
-      OpenClientStateKey(root_key, google_update::kChromeFrameAppGuid,
-                         KEY_QUERY_VALUE, &key)) {
-    succeeded = (key.ReadValue(kUninstallRegistryValueName, path,
-                               size) == ERROR_SUCCESS);
+  if (configuration.has_chrome_frame() && GetSetupExePathForGuidFromRegistry(
+          system_level, google_update::kChromeFrameAppGuid, path, size)) {
+    return true;
   }
 
-  // Make a last-ditch effort to look in Chrome's client state key.
-  if (!succeeded &&
-      OpenClientStateKey(root_key, configuration.chrome_app_guid(),
-                         KEY_QUERY_VALUE, &key)) {
-    succeeded = (key.ReadValue(kUninstallRegistryValueName, path,
-                               size) == ERROR_SUCCESS);
+  // Make a last-ditch effort to look in the Chrome and App Host client state
+  // keys.
+  if (GetSetupExePathForGuidFromRegistry(
+          system_level, configuration.chrome_app_guid(), path, size)) {
+    return true;
+  }
+  if (configuration.has_app_host() && GetSetupExePathForGuidFromRegistry(
+          system_level, google_update::kChromeAppHostAppGuid, path, size)) {
+    return true;
   }
 
-  return succeeded;
+  return false;
 }
 
 // Calls CreateProcess with good default parameters and waits for the process
 // to terminate returning the process exit code.
 bool RunProcessAndWait(const wchar_t* exe_path, wchar_t* cmdline,
                        int* exit_code) {
   STARTUPINFOW si = {sizeof(si)};
   PROCESS_INFORMATION pi = {0};
   if (!::CreateProcess(exe_path, cmdline, NULL, NULL, FALSE, CREATE_NO_WINDOW,
                        NULL, NULL, &si, &pi)) {
@@ skipping 566 matching lines @@
     case 1:
       dest8[count - 1] = c;
   }
 
   while (adjcount-- > 0)  // Copy the rest, 4 bytes/32 bits at a time
     *(dest32++) = fill;
 
   return dest;
 }
 }  // extern "C"