gecko-dev/layout/style/nsLayoutStylesheetCache.h

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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/. */
#ifndef nsLayoutStylesheetCache_h__
#define nsLayoutStylesheetCache_h__
#include "nsIMemoryReporter.h"
#include "nsIObserver.h"
#include "base/shared_memory.h"
#include "mozilla/Attributes.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/PreferenceSheet.h"
#include "mozilla/NotNull.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/css/Loader.h"
class nsIFile;
class nsIURI;
namespace mozilla {
class CSSStyleSheet;
} // namespace mozilla
namespace mozilla {
namespace css {
// Enum defining how error should be handled.
enum FailureAction { eCrash = 0, eLogToConsole };
} // namespace css
} // namespace mozilla
// Reference counted wrapper around a base::SharedMemory that will store the
// User Agent style sheets.
struct nsLayoutStylesheetCacheShm final {
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(nsLayoutStylesheetCacheShm)
base::SharedMemory mShm;
private:
~nsLayoutStylesheetCacheShm() = default;
};
class nsLayoutStylesheetCache final : public nsIObserver,
public nsIMemoryReporter {
public:
using Shm = nsLayoutStylesheetCacheShm;
NS_DECL_ISUPPORTS
NS_DECL_NSIOBSERVER
NS_DECL_NSIMEMORYREPORTER
static nsLayoutStylesheetCache* Singleton();
#define STYLE_SHEET(identifier_, url_, shared_) \
mozilla::NotNull<mozilla::StyleSheet*> identifier_##Sheet();
#include "mozilla/UserAgentStyleSheetList.h"
#undef STYLE_SHEET
mozilla::StyleSheet* GetUserContentSheet();
mozilla::StyleSheet* GetUserChromeSheet();
mozilla::StyleSheet* ChromePreferenceSheet();
mozilla::StyleSheet* ContentPreferenceSheet();
static void InvalidatePreferenceSheets();
static void Shutdown();
static void SetUserContentCSSURL(nsIURI* aURI);
size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
// Set the shared memory segment to load the shared UA sheets from.
// Called early on in a content process' life from
// ContentChild::InitSharedUASheets, before the nsLayoutStylesheetCache
// singleton has been created.
static void SetSharedMemory(const base::SharedMemoryHandle& aHandle,
uintptr_t aAddress);
// Obtain a shared memory handle for the shared UA sheets to pass into a
// content process. Called by ContentParent::InitInternal shortly after
// a content process has been created.
bool ShareToProcess(base::ProcessId aProcessId,
base::SharedMemoryHandle* aHandle);
// Returns the address of the shared memory segment that holds the shared UA
// sheets.
uintptr_t GetSharedMemoryAddress() {
return mSharedMemory ? uintptr_t(mSharedMemory->mShm.memory()) : 0;
}
// Size of the shared memory buffer we'll create to store the shared UA
// sheets. We choose a value that is big enough on both 64 bit and 32 bit.
//
// If this isn't big enough for the current contents of the shared UA
// sheets, we'll crash under InitSharedSheetsInParent.
static constexpr size_t kSharedMemorySize = 1024 * 400;
private:
// Shared memory header.
struct Header {
static constexpr uint32_t kMagic = 0x55415353;
uint32_t mMagic; // Must be set to kMagic.
const ServoCssRules* mSheets[size_t(mozilla::UserAgentStyleSheetID::Count)];
uint8_t mBuffer[1];
};
nsLayoutStylesheetCache();
~nsLayoutStylesheetCache();
void InitFromProfile();
void InitSharedSheetsInParent();
void InitSharedSheetsInChild(already_AddRefed<Shm> aSharedMemory);
void InitMemoryReporter();
void LoadSheetURL(const char* aURL, RefPtr<mozilla::StyleSheet>* aSheet,
mozilla::css::SheetParsingMode aParsingMode,
mozilla::css::FailureAction aFailureAction);
void LoadSheetFile(nsIFile* aFile, RefPtr<mozilla::StyleSheet>* aSheet,
mozilla::css::SheetParsingMode aParsingMode,
mozilla::css::FailureAction aFailureAction);
void LoadSheet(nsIURI* aURI, RefPtr<mozilla::StyleSheet>* aSheet,
mozilla::css::SheetParsingMode aParsingMode,
mozilla::css::FailureAction aFailureAction);
void LoadSheetFromSharedMemory(const char* aURL,
RefPtr<mozilla::StyleSheet>* aSheet,
mozilla::css::SheetParsingMode aParsingMode,
Shm* aSharedMemory, Header* aHeader,
mozilla::UserAgentStyleSheetID aSheetID);
void BuildPreferenceSheet(RefPtr<mozilla::StyleSheet>* aSheet,
const mozilla::PreferenceSheet::Prefs&);
static mozilla::StaticRefPtr<nsLayoutStylesheetCache> gStyleCache;
static mozilla::StaticRefPtr<mozilla::css::Loader> gCSSLoader;
static mozilla::StaticRefPtr<nsIURI> gUserContentSheetURL;
#define STYLE_SHEET(identifier_, url_, shared_) \
RefPtr<mozilla::StyleSheet> m##identifier_##Sheet;
#include "mozilla/UserAgentStyleSheetList.h"
#undef STYLE_SHEET
RefPtr<mozilla::StyleSheet> mChromePreferenceSheet;
RefPtr<mozilla::StyleSheet> mContentPreferenceSheet;
RefPtr<mozilla::StyleSheet> mUserChromeSheet;
RefPtr<mozilla::StyleSheet> mUserContentSheet;
// Shared memory segment storing shared style sheets.
RefPtr<Shm> mSharedMemory;
// How much of the shared memory buffer we ended up using. Used for memory
// reporting.
size_t mUsedSharedMemory;
// The shared memory to use once the nsLayoutStylesheetCache instance is
// created.
static mozilla::StaticRefPtr<Shm> sSharedMemory;
};
#endif