toolkit/xre/DllPrefetchExperimentRegistryInfo.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_DllPrefetchExperimentRegistryInfo_h
   8 #define mozilla_DllPrefetchExperimentRegistryInfo_h
   9
  10 #include "mozilla/Maybe.h"
  11 #include "mozilla/WinHeaderOnlyUtils.h"
  12 #include "nsWindowsHelpers.h"
  13
  14 /**
  15  * This is a temporary file in order to conduct an experiment on the impact of
  16  * startup time on retention (see Bug 1640087).
  17  * This was generally adapted from LauncherRegistryInfo.h
  18  */
  19
  20 namespace mozilla {
  21
  22 enum class AlteredDllPrefetchMode {
  23   CurrentPrefetch,
  24   NoPrefetch,
  25   OptimizedPrefetch
  26 };
  27
  28 class DllPrefetchExperimentRegistryInfo final {
  29  public:
  30   DllPrefetchExperimentRegistryInfo() : mBinPath(GetFullBinaryPath().get()) {}
  31   ~DllPrefetchExperimentRegistryInfo() {}
  32
  33   Result<Ok, nsresult> ReflectPrefToRegistry(int32_t aVal);
  34   Result<Ok, nsresult> ReadRegistryValueData(DWORD expectedType);
  35
  36   AlteredDllPrefetchMode GetAlteredDllPrefetchMode();
  37
  38  private:
  39   Result<Ok, nsresult> Open();
  40
  41   nsAutoRegKey mRegKey;
  42   nsString mBinPath;
  43   int32_t mPrefetchMode;
  44
  45   static const wchar_t kExperimentSubKeyPath[];
  46 };
  47
  48 }  // namespace mozilla
  49
  50 #endif  // mozilla_DllPrefetchExperimentRegistryInfo_h