gecko-dev/toolkit/xre/SafeMode.h
2019-08-20 19:51:34 +00:00

93 lines
2.6 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
#ifndef mozilla_SafeMode_h
#define mozilla_SafeMode_h
// NB: This code must be able to run apart from XPCOM
#include "mozilla/CmdLineAndEnvUtils.h"
#include "mozilla/Maybe.h"
#if defined(XP_WIN)
# include "mozilla/PolicyChecks.h"
# include <windows.h>
#endif // defined(XP_WIN)
// Undo X11/X.h's definition of None
#undef None
namespace mozilla {
enum class SafeModeFlag : uint32_t {
None = 0,
Unset = (1 << 0),
NoKeyPressCheck = (1 << 1),
};
MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(SafeModeFlag)
template <typename CharT>
inline Maybe<bool> IsSafeModeRequested(
int& aArgc, CharT* aArgv[],
const SafeModeFlag aFlags = SafeModeFlag::Unset) {
CheckArgFlag checkArgFlags = CheckArgFlag::None;
if (aFlags & SafeModeFlag::Unset) {
checkArgFlags |= CheckArgFlag::RemoveArg;
}
ArgResult ar =
CheckArg(aArgc, aArgv, GetLiteral<CharT, FlagLiteral::safemode>(),
static_cast<const CharT**>(nullptr), checkArgFlags);
if (ar == ARG_BAD) {
return Nothing();
}
bool result = ar == ARG_FOUND;
#if defined(XP_WIN)
// If the shift key is pressed and the ctrl and / or alt keys are not pressed
// during startup, start in safe mode. GetKeyState returns a short and the
// high order bit will be 1 if the key is pressed. By masking the returned
// short with 0x8000 the result will be 0 if the key is not pressed and
// non-zero otherwise.
if (!(aFlags & SafeModeFlag::NoKeyPressCheck) &&
(GetKeyState(VK_SHIFT) & 0x8000) && !(GetKeyState(VK_CONTROL) & 0x8000) &&
!(GetKeyState(VK_MENU) & 0x8000) &&
!EnvHasValue("MOZ_DISABLE_SAFE_MODE_KEY")) {
result = true;
}
if (result && PolicyCheckBoolean(L"DisableSafeMode")) {
result = false;
}
#endif // defined(XP_WIN)
#if defined(XP_MACOSX)
if (!(aFlags & SafeModeFlag::NoKeyPressCheck) &&
(GetCurrentEventKeyModifiers() & optionKey) &&
!EnvHasValue("MOZ_DISABLE_SAFE_MODE_KEY")) {
result = true;
}
#endif // defined(XP_MACOSX)
// The Safe Mode Policy should not be enforced for the env var case
// (used by updater and crash-recovery).
if (EnvHasValue("MOZ_SAFE_MODE_RESTART")) {
result = true;
if (aFlags & SafeModeFlag::Unset) {
// unset the env variable
SaveToEnv("MOZ_SAFE_MODE_RESTART=");
}
}
return Some(result);
}
} // namespace mozilla
#endif // mozilla_SafeMode_h