gecko-dev/layout/style/ServoUtils.h
Cameron McCormack 4f45ef2141 Bug 1498755 - Part 3: Merge AssertIsMainThreadOrServo{FontMetrics,LangFontPrefsCache}Locked r=emilio
Depends on D8644

Differential Revision: https://phabricator.services.mozilla.com/D8645

--HG--
extra : moz-landing-system : lando
2018-10-14 00:05:50 +00:00

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1.5 KiB
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/* -*- 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 http://mozilla.org/MPL/2.0/. */
/* some utilities for Gecko to use for Servo initialization and assertions */
#ifndef mozilla_ServoUtils_h
#define mozilla_ServoUtils_h
#include "mozilla/Assertions.h"
#include "mozilla/TypeTraits.h"
#include "MainThreadUtils.h"
namespace mozilla {
// Defined in GeckoBindings.cpp.
void InitializeServo();
void ShutdownServo();
void AssertIsMainThreadOrServoFontMetricsLocked();
class ServoStyleSet;
extern ServoStyleSet* sInServoTraversal;
inline bool IsInServoTraversal()
{
// The callers of this function are generally main-thread-only _except_
// for potentially running during the Servo traversal, in which case they may
// take special paths that avoid writing to caches and the like. In order
// to allow those callers to branch efficiently without checking TLS, we
// maintain this static boolean. However, the danger is that those callers
// are generally unprepared to deal with non-Servo-but-also-non-main-thread
// callers, and are likely to take the main-thread codepath if this function
// returns false. So we assert against other non-main-thread callers here.
MOZ_ASSERT(sInServoTraversal || NS_IsMainThread());
return sInServoTraversal;
}
} // namespace mozilla
#endif // mozilla_ServoUtils_h