tenfourfox/layout/style/RuleProcessorCache.h
Cameron Kaiser c9b2922b70 hello FPR
2017-04-19 00:56:45 -07:00

151 lines
4.9 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 http://mozilla.org/MPL/2.0/. */
/*
* cache of re-usable nsCSSRuleProcessors for given sets of style sheets
*/
#ifndef mozilla_RuleProcessorCache_h
#define mozilla_RuleProcessorCache_h
#include "mozilla/MemoryReporting.h"
#include "mozilla/StaticPtr.h"
#include "nsCSSRuleProcessor.h"
#include "nsExpirationTracker.h"
#include "nsIMediaList.h"
#include "nsIMemoryReporter.h"
#include "nsTArray.h"
class nsCSSRuleProcessor;
namespace mozilla {
class CSSStyleSheet;
namespace css {
class DocumentRule;
} // namespace css
} // namespace mozilla
namespace mozilla {
/**
* The RuleProcessorCache is a singleton object that caches
* nsCSSRuleProcessors keyed off a list of style sheets and the result of
* evaluating all @-moz-documents in the style sheets. nsStyleSet gets and
* puts nsCSSRuleProcessors from/to the RuleProcessorCache.
*
* State bits on CSSStyleSheet and nsCSSRuleProcessor track whether they are in
* the RuleProcessorCache. This lets us remove them from the RuleProcessorCache
* when they're going away.
*/
class RuleProcessorCache final : public nsIMemoryReporter
{
NS_DECL_ISUPPORTS
NS_DECL_NSIMEMORYREPORTER
public:
static nsCSSRuleProcessor* GetRuleProcessor(
const nsTArray<CSSStyleSheet*>& aSheets,
nsPresContext* aPresContext);
static void PutRuleProcessor(
const nsTArray<CSSStyleSheet*>& aSheets,
nsTArray<css::DocumentRule*>&& aDocumentRulesInSheets,
const nsDocumentRuleResultCacheKey& aCacheKey,
nsCSSRuleProcessor* aRuleProcessor);
static void StartTracking(nsCSSRuleProcessor* aRuleProcessor);
static void StopTracking(nsCSSRuleProcessor* aRuleProcessor);
#ifdef DEBUG
static bool HasRuleProcessor(nsCSSRuleProcessor* aRuleProcessor);
#endif
static void RemoveRuleProcessor(nsCSSRuleProcessor* aRuleProcessor);
static void RemoveSheet(CSSStyleSheet* aSheet);
static void Shutdown() { gShutdown = true; gRuleProcessorCache = nullptr; }
size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);
private:
class ExpirationTracker : public nsExpirationTracker<nsCSSRuleProcessor,3>
{
public:
explicit ExpirationTracker(RuleProcessorCache* aCache)
: nsExpirationTracker<nsCSSRuleProcessor,3>(
10000, "RuleProcessorCache::ExpirationTracker")
, mCache(aCache) {}
void RemoveObjectIfTracked(nsCSSRuleProcessor* aRuleProcessor);
virtual void NotifyExpired(nsCSSRuleProcessor* aRuleProcessor) override {
mCache->RemoveRuleProcessor(aRuleProcessor);
}
private:
RuleProcessorCache* mCache;
};
RuleProcessorCache() : mExpirationTracker(this) {}
~RuleProcessorCache();
void InitMemoryReporter();
static bool EnsureGlobal();
static StaticRefPtr<RuleProcessorCache> gRuleProcessorCache;
static bool gShutdown;
void DoRemoveSheet(CSSStyleSheet* aSheet);
nsCSSRuleProcessor* DoGetRuleProcessor(
const nsTArray<CSSStyleSheet*>& aSheets,
nsPresContext* aPresContext);
void DoPutRuleProcessor(const nsTArray<CSSStyleSheet*>& aSheets,
nsTArray<css::DocumentRule*>&& aDocumentRulesInSheets,
const nsDocumentRuleResultCacheKey& aCacheKey,
nsCSSRuleProcessor* aRuleProcessor);
#ifdef DEBUG
bool DoHasRuleProcessor(nsCSSRuleProcessor* aRuleProcessor);
#endif
void DoRemoveRuleProcessor(nsCSSRuleProcessor* aRuleProcessor);
void DoStartTracking(nsCSSRuleProcessor* aRuleProcessor);
void DoStopTracking(nsCSSRuleProcessor* aRuleProcessor);
struct DocumentEntry {
nsDocumentRuleResultCacheKey mCacheKey;
RefPtr<nsCSSRuleProcessor> mRuleProcessor;
};
struct Entry {
nsTArray<CSSStyleSheet*> mSheets;
nsTArray<css::DocumentRule*> mDocumentRulesInSheets;
nsTArray<DocumentEntry> mDocumentEntries;
};
// Function object to test whether an Entry object has a given sheet
// in its mSheets array. If it does, removes all of its rule processors
// before returning true.
struct HasSheet_ThenRemoveRuleProcessors {
HasSheet_ThenRemoveRuleProcessors(RuleProcessorCache* aCache,
CSSStyleSheet* aSheet)
: mCache(aCache), mSheet(aSheet) {}
bool operator()(Entry& aEntry) {
if (aEntry.mSheets.Contains(mSheet)) {
for (DocumentEntry& de : aEntry.mDocumentEntries) {
de.mRuleProcessor->SetInRuleProcessorCache(false);
mCache->mExpirationTracker.RemoveObjectIfTracked(de.mRuleProcessor);
}
return true;
}
return false;
}
RuleProcessorCache* mCache;
CSSStyleSheet* mSheet;
};
ExpirationTracker mExpirationTracker;
nsTArray<Entry> mEntries;
};
} // namespace mozilla
#endif // mozilla_RuleProcessorCache_h