Ensuring Google Update at user-level is installed alongside App Host, for the quick-enable App Host…

chrome/installer/util/google_update_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.
+
+#include "chrome/installer/util/google_update_util.h"
+
+#include "base/command_line.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/logging.h"
+#include "base/process_util.h"
+#include "base/string16.h"
+#include "base/win/registry.h"
+#include "chrome/installer/launcher_support/chrome_launcher_support.h"
+#include "chrome/installer/util/google_update_constants.h"
+
+using base::win::RegKey;
+
+namespace google_update {
+
+FilePath GetGoogleUpdateSetupExe(bool system_install) {

[erikwright (departed), 2012/09/20 18:00:01]

doesn't match name in header file, but it's probably not needed outside this CC
so maybe just remove from header and put in anonymous namespace.

[huangs, 2012/09/21 01:43:14]

Done.

+  const HKEY root_key = system_install ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
+  RegKey update_key;
+
+  if (update_key.Open(root_key, google_update::kRegPathGoogleUpdate,
+                      KEY_QUERY_VALUE) == ERROR_SUCCESS) {
+    string16 path_str;
+    string16 version_str;
+    if ((update_key.ReadValue(google_update::kRegPathField,
+                              &path_str) == ERROR_SUCCESS) &&

[huangs, 2012/09/20 15:24:54]

path_str will fit in the previous line, but right now I think it's better to
maintain visual symmetry!

+        (update_key.ReadValue(google_update::kRegGoogleUpdateVersion,
+                              &version_str) == ERROR_SUCCESS)) {
+      FilePath google_update_setup(FilePath(path_str).DirName().
+                                   Append(version_str).
+                                   Append(kGoogleUpdateSetupExecutable));
+      if (file_util::PathExists(google_update_setup))
+        return google_update_setup;

[erikwright (departed), 2012/09/20 18:00:01]

if this doesn't exist, it's very unusual. LOG an ERROR.

[huangs, 2012/09/21 01:43:14]

Done.

+    }
+  }
+  return FilePath();
+}
+
+void AppendUserLevelGoogleUpdateInstallParam(CommandLine& cmd_line) {
+  // Constants are found in googleclient/omaha/base/const_cmd_line.h.

[grt (UTC plus 2), 2012/09/20 17:58:51]

please refer to omaha code by way of code.google.com/p/omaha here and
everywhere.

[huangs, 2012/09/21 01:43:14]

Done.  Also, I had a typo; it's in omaha/common.

+  cmd_line.AppendArg("/install");
+  // The "&" can be used in base::LaunchProcess() without quotation
+  // (this is problematic only if run from command prompt).
+  cmd_line.AppendArg("runtime=true&needsadmin=false");
+  cmd_line.AppendArg("/silent");
+}
+
+bool EnsureUserLevelGoogleUpdateInstalled() {
+  VLOG(1) << "Ensuring Google Update is installed at user level";
+  if (GetGoogleUpdateSetupExe(false).empty()) {

[erikwright (departed), 2012/09/20 18:00:01]

I have mixed feelings about using the presence of the GoogleUpdateSetup.exe to
determine if it's already at user-level.

Probably the right thing is to just check in the Clients key.

[huangs, 2012/09/21 01:43:14]

Done.  Added simple local routine IsGoogleUpdateInstalled() for now; will move
it upon request (e.g. to GoogleUpdateSettings?).

+    FilePath google_update_setup(GetGoogleUpdateSetupExe(true));
+    if (!google_update_setup.empty()) {
+      CommandLine cmd_line(google_update_setup);
+      AppendUserLevelGoogleUpdateInstallParam(cmd_line);
+      VLOG(1) << "Command line: " << cmd_line.GetCommandLineString();
+      return base::LaunchProcess(cmd_line, base::LaunchOptions(), NULL);

[erikwright (departed), 2012/09/20 18:00:01]

Probably appropriate to wait up to some timeout for the process to exit, and
return its exit code.

[huangs, 2012/09/21 01:43:14]

Wrote the time-out code, but can I output the return code in PLOG(ERROR) and
return bool still instead?

+    } else {
+      LOG(ERROR) << "Cannot find " << kGoogleUpdateSetupExecutable;
+    }
+  } else {
+    VLOG(1) << "Google Update already installed";
+    return true;
+  }
+  return false;
+}
+
+}  // namespace google_update