Disable lock if no credentials are present

chrome/browser/signin/local_auth.cc

 // Copyright 2013 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/browser/signin/local_auth.h"
 
 #include "base/base64.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
@@ skipping 180 matching lines @@
   ProfileInfoCache& info =
       g_browser_process->profile_manager()->GetProfileInfoCache();
   size_t info_index = info.GetIndexOfProfileWithPath(profile->GetPath());
   if (info_index == std::string::npos) {
     NOTREACHED();  // This should never happen but fail safely if it does.
     return false;
   }
   return ValidateLocalAuthCredentials(info_index, password);
 }
 
+bool LocalAuthCredentialsExist(size_t profile_info_index) {
+  ProfileInfoCache& info =
+      g_browser_process->profile_manager()->GetProfileInfoCache();
+
+  std::string encodedhash =
+      info.GetLocalAuthCredentialsOfProfileAtIndex(profile_info_index);
+
+  return !encodedhash.empty();
+}
+
+bool LocalAuthCredentialsExist(const Profile* profile) {
+  DCHECK(profile);
+
+  ProfileInfoCache& info =
+      g_browser_process->profile_manager()->GetProfileInfoCache();
+  size_t info_index = info.GetIndexOfProfileWithPath(profile->GetPath());
+  if (info_index == std::string::npos) {

[msw, 2014/08/22 21:46:48]

Should this logic be in the |profile_info_index| function?
Ditto for ValidateLocalAuthCredential and SetLocalAuthCredentials.

[Mike Lerman, 2014/08/25 14:44:30]

I turned the NOTREACHED into a DCHECK and put it on top of each of the other
functions.

I also refactored the other common code from the methods that take a Profile*
into an anonymous helper called GetProfileInfoIndexOfProfile.

[msw, 2014/08/25 17:39:54]

I appreciate the cleanup, but you've removed the "fail safely" mechanisms.

[Mike Lerman, 2014/08/25 18:11:37]

Did I? The DCHECK(profile) is now in the common method, and info_index ==
std::string::npos will be caught by DCHECK_NE(info_index, ::npos) in each of the
three |profile_info_index| methods. Which fail safety is gone?

[msw, 2014/08/25 18:54:03]

The early return [false] statements. The old code would NOTREACHED then early
return [false]. The new code does as DCHECK and then continues function
execution, potentially crashing or employing undefined behavior.

[Mike Lerman, 2014/08/25 19:05:11]

Gotcha, done.

+    NOTREACHED();  // This should never happen but fail safely if it does.
+    return false;
+  }
+  return LocalAuthCredentialsExist(info_index);
+

[msw, 2014/08/22 21:46:48]

nit: remove blank line.

[Mike Lerman, 2014/08/25 14:44:30]

Done.

+}
+
 }  // namespace chrome