1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180
|
/*
* Copyright (C) 2012 Google, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef Supplementable_h
#define Supplementable_h
#include <wtf/Assertions.h>
#include <wtf/HashMap.h>
#include <wtf/MainThread.h>
#include <wtf/text/ASCIILiteral.h>
#if ASSERT_ENABLED
#include <wtf/Threading.h>
#endif
namespace WebCore {
// What you should know about Supplementable and Supplement
// ========================================================
// Supplementable and Supplement instances are meant to be thread local. They
// should only be accessed from within the thread that created them. The
// 2 classes are not designed for safe access from another thread. Violating
// this design assumption can result in memory corruption and unpredictable
// behavior.
//
// What you should know about the Supplement keys
// ==============================================
// The Supplement is expected to use the same ASCIILiteral instance as its
// key. The Supplementable's SupplementMap will use the address of the
// string as the key and not the characters themselves. Hence, 2 strings with
// the same characters will be treated as 2 different keys.
//
// In practice, it is recommended that Supplements implements a static method
// for returning its key to use. For example:
//
// class MyClass : public Supplement<MySupplementable> {
// ...
// static ASCIILiteral supplementName();
// }
//
// ASCIILiteral MyClass::supplementName()
// {
// return "MyClass"_s;
// }
//
// An example of the using the key:
//
// MyClass* MyClass::from(MySupplementable* host)
// {
// return reinterpret_cast<MyClass*>(Supplement<MySupplementable>::from(host, supplementName()));
// }
class SupplementBase {
public:
virtual ~SupplementBase() = default;
// To allow a downcast from Supplement<Foo> to a subclass Bar, we require
// a TypeCastTraits specialization. The isBar() function needed for this
// specialization can be implemented here and overridden in the base class.
virtual bool isCSSNumericFactory() const { return false; }
virtual bool isDOMCSSPaintWorklet() const { return false; }
virtual bool isDOMCSSRegisterCustomProperty() const { return false; }
virtual bool isDOMWindowCaches() const { return false; }
virtual bool isDOMWindowIndexedDatabase() const { return false; }
virtual bool isDOMWindowTrustedTypes() const { return false; }
virtual bool isDeviceMotionController() const { return false; }
virtual bool isDeviceOrientationController() const { return false; }
virtual bool isDocumentMediaElement() const { return false; }
virtual bool isDocumentPictureInPicture() const { return false; }
virtual bool isDocumentStorageAccess() const { return false; }
virtual bool isGeolocationController() const { return false; }
virtual bool isHTMLVideoElementPictureInPicture() const { return false; }
virtual bool isInternalSettingsWrapper() const { return false; }
virtual bool isLocalDOMWindowMediaControls() const { return false; }
virtual bool isLocalDOMWindowSpeechSynthesis() const { return false; }
virtual bool isMediaKeySystemController() const { return false; }
virtual bool isNavigatorAudioSession() const { return false; }
virtual bool isNavigatorBeacon() const { return false; }
virtual bool isNavigatorClipboard() const { return false; }
virtual bool isNavigatorContacts() const { return false; }
virtual bool isNavigatorCookieConsent() const { return false; }
virtual bool isNavigatorCredentials() const { return false; }
virtual bool isNavigatorGamepad() const { return false; }
virtual bool isNavigatorGeolocation() const { return false; }
virtual bool isNavigatorLoginStatus() const { return false; }
virtual bool isNavigatorMediaCapabilities() const { return false; }
virtual bool isNavigatorMediaDevices() const { return false; }
virtual bool isNavigatorMediaSession() const { return false; }
virtual bool isNavigatorPermissions() const { return false; }
virtual bool isNavigatorScreenWakeLock() const { return false; }
virtual bool isNavigatorUserActivation() const { return false; }
virtual bool isNavigatorWebDriver() const { return false; }
virtual bool isNotificationController() const { return false; }
virtual bool isServiceWorkerRegistrationBackgroundFetchAPI() const { return false; }
virtual bool isServiceWorkerRegistrationPushAPI() const { return false; }
virtual bool isUserMediaController() const { return false; }
virtual bool isWorkerGlobalScopeCaches() const { return false; }
virtual bool isWorkerGlobalScopeIndexedDatabase() const { return false; }
virtual bool isWorkerGlobalScopeTrustedTypes() const { return false; }
virtual bool isWorkerNavigatorMediaCapabilities() const { return false; }
virtual bool isWorkerNavigatorPermissions() const { return false; }
};
template<typename T>
class Supplementable;
template<typename T>
class Supplement : public SupplementBase {
public:
#if ASSERT_ENABLED || ENABLE(SECURITY_ASSERTIONS)
virtual bool isRefCountedWrapper() const { return false; }
#endif
static void provideTo(Supplementable<T>* host, ASCIILiteral key, std::unique_ptr<Supplement<T>> supplement)
{
host->provideSupplement(key, WTFMove(supplement));
}
static Supplement<T>* from(Supplementable<T>* host, ASCIILiteral key)
{
return host ? host->requireSupplement(key) : 0;
}
};
template<typename T>
class Supplementable {
public:
void provideSupplement(ASCIILiteral key, std::unique_ptr<Supplement<T>> supplement)
{
ASSERT(canCurrentThreadAccessThreadLocalData(m_thread));
ASSERT(!m_supplements.get(key));
m_supplements.add(key, WTFMove(supplement));
}
Supplement<T>* requireSupplement(ASCIILiteral key)
{
ASSERT(canCurrentThreadAccessThreadLocalData(m_thread));
return m_supplements.get(key);
}
#if ASSERT_ENABLED
protected:
Supplementable() = default;
#endif
private:
using SupplementMap = HashMap<ASCIILiteral, std::unique_ptr<Supplement<T>>>;
SupplementMap m_supplements;
#if ASSERT_ENABLED
const Ref<Thread> m_thread { Thread::currentSingleton() };
#endif
};
} // namespace WebCore
#endif // Supplementable_h
|