Unregister previous ChromeFrame UA strings registered under the PostPlatform ...

chrome_frame/chrome_tab.cc

 // Copyright (c) 2010 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.
 
 // chrome_tab.cc : Implementation of DLL Exports.
 
 // Include without path to make GYP build see it.
 #include "chrome_tab.h"  // NOLINT
 
 #include <atlsecurity.h>
+#include <vector>
 
 #include "base/at_exit.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/file_version_info.h"
 #include "base/lock.h"
 #include "base/logging.h"
 #include "base/logging_win.h"
 #include "base/path_service.h"
 #include "base/string_number_conversions.h"
@@ skipping 398 matching lines @@
   }
 
   return _AtlModule.DllGetClassObject(rclsid, riid, ppv);
 }
 
 const wchar_t kPostPlatformUAKey[] =
     L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\"
     L"User Agent\\Post Platform";
 const wchar_t kChromeFramePrefix[] = L"chromeframe/";
 
+// Returns the list of chrome frame UA agents registered under the
+// kPostPlatformUAKey registry key.
+void GetRegisteredChromeFrameUAStrings(HKEY parent_hive,
+                                       std::vector<std::wstring>* ua_values) {
+  base::win::RegistryValueIterator ua_registration(parent_hive,
+                                                   kPostPlatformUAKey);
+  std::wstring chrome_frame_ua_pattern = kChromeFramePrefix;
+  chrome_frame_ua_pattern += L"*";
+  while (ua_registration.Valid()) {
+    if (MatchPattern(ua_registration.Name(),
+                     chrome_frame_ua_pattern)) {
+      ua_values->push_back(ua_registration.Name());
+    }
+    ++ua_registration;
+  }
+}
+
 // To delete the user agent, set value to NULL.
 // The is_system parameter indicates whether this is a per machine or a per
 // user installation.
 HRESULT SetChromeFrameUA(bool is_system, const wchar_t* value) {
   HRESULT hr = E_FAIL;
   HKEY parent_hive = is_system ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
 
+  // If we are registering the ChromeFrame UA in the kPostPlatformUAKey key

[amit, 2011/01/14 05:26:01]

why not delete all the matching values anyway? If |value| is not NULL then we
just have to write a new value.

+  // make sure that we unregister ChromeFrame UA strings registered by previous
+  // ChromeFrame versions.
+  std::vector<std::wstring> cf_ua_list;
+  if (value) {
+    GetRegisteredChromeFrameUAStrings(parent_hive, &cf_ua_list);
+  }
   RegKey ua_key;
   if (ua_key.Create(parent_hive, kPostPlatformUAKey, KEY_WRITE)) {
     std::wstring chrome_frame_ua_value_name = kChromeFramePrefix;
     chrome_frame_ua_value_name += GetCurrentModuleVersion();
     if (value) {
+      for (size_t ua_idx = 0; ua_idx < cf_ua_list.size(); ua_idx++) {
+        ua_key.DeleteValue(cf_ua_list[ua_idx].c_str());
+      }
       ua_key.WriteValue(chrome_frame_ua_value_name.c_str(), value);
     } else {
       ua_key.DeleteValue(chrome_frame_ua_value_name.c_str());
     }
     hr = S_OK;
   } else {
     DLOG(ERROR) << __FUNCTION__ << ": " << kPostPlatformUAKey;
     hr = E_UNEXPECTED;
   }
   return hr;
@@ skipping 337 matching lines @@
     sd.GetDacl(&new_dacl);
     new_dacl.AddAllowedAce(token_.GetUser(), GENERIC_WRITE | GENERIC_READ);
     if (AtlSetDacl(object_name.c_str(), SE_REGISTRY_KEY, new_dacl)) {
       result = SetOrDeleteMimeHandlerKey(enable, HKEY_LOCAL_MACHINE);
     }
   }
 
   backup.RestoreSecurity(object_name.c_str());
   return result;
 }