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c4745d28b1
CLOSED TREE Backed out changeset 7613fc978d36 (bug 1142794) Backed out changeset e5f0cb31263d (bug 1142784) Backed out changeset dcd0af73ac84 (bug 1142784) Backed out changeset 034f9c8e79ee (bug 1142784) Backed out changeset ce0ee37e3ca9 (bug 1142775) Backed out changeset 1519b8f2bbba (bug 1142761) Backed out changeset 26fd55677841 (bug 1139683) Backed out changeset 7ebc76a450c3 (bug 1144819) Backed out changeset 92adb459d519 (bug 1143810)
691 lines
28 KiB
C++
691 lines
28 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
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* vim: set ts=8 sts=4 et sw=4 tw=99:
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#ifndef js_Proxy_h
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#define js_Proxy_h
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#include "mozilla/Maybe.h"
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#include "jsfriendapi.h"
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#include "js/CallNonGenericMethod.h"
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#include "js/Class.h"
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namespace js {
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using JS::AutoIdVector;
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using JS::CallArgs;
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using JS::HandleId;
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using JS::HandleObject;
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using JS::HandleValue;
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using JS::IsAcceptableThis;
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using JS::MutableHandle;
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using JS::MutableHandleObject;
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using JS::MutableHandleValue;
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using JS::NativeImpl;
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using JS::ObjectOpResult;
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using JS::PrivateValue;
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using JS::Value;
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class RegExpGuard;
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class JS_FRIEND_API(Wrapper);
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/*
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* A proxy is a JSObject with highly customizable behavior. ES6 specifies a
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* single kind of proxy, but the customization mechanisms we use to implement
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* ES6 Proxy objects are also useful wherever an object with weird behavior is
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* wanted. Proxies are used to implement:
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*
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* - the scope objects used by the Debugger's frame.eval() method
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* (see js::GetDebugScopeForFunction)
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*
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* - the khuey hack, whereby a whole compartment can be blown away
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* even if other compartments hold references to objects in it
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* (see js::NukeCrossCompartmentWrappers)
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*
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* - XPConnect security wrappers, which protect chrome from malicious content
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* (js/xpconnect/wrappers)
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*
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* - DOM objects with special property behavior, like named getters
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* (dom/bindings/Codegen.py generates these proxies from WebIDL)
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*
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* - semi-transparent use of objects that live in other processes
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* (CPOWs, implemented in js/ipc)
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*
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* ### Proxies and internal methods
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*
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* ES6 draft rev 27 (24 August 2014) specifies 14 internal methods. The runtime
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* semantics of just about everything a script can do to an object is specified
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* in terms of these internal methods. For example:
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*
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* JS code ES6 internal method that gets called
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* --------------------------- --------------------------------
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* obj.prop obj.[[Get]](obj, "prop")
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* "prop" in obj obj.[[HasProperty]]("prop")
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* new obj() obj.[[Construct]](<empty argument List>)
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* for (k in obj) {} obj.[[Enumerate]]()
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*
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* With regard to the implementation of these internal methods, there are three
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* very different kinds of object in SpiderMonkey.
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*
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* 1. Native objects' internal methods are implemented in vm/NativeObject.cpp,
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* with duplicate (but functionally identical) implementations scattered
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* through the ICs and JITs.
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*
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* 2. Certain non-native objects have internal methods that are implemented as
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* magical js::ObjectOps hooks. We're trying to get rid of these.
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*
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* 3. All other objects are proxies. A proxy's internal methods are
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* implemented in C++, as the virtual methods of a C++ object stored on the
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* proxy, known as its handler.
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*
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* This means that just about anything you do to a proxy will end up going
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* through a C++ virtual method call. Possibly several. There's no reason the
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* JITs and ICs can't specialize for particular proxies, based on the handler;
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* but currently we don't do much of this, so the virtual method overhead
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* typically is actually incurred.
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*
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* ### The proxy handler hierarchy
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*
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* A major use case for proxies is to forward each internal method call to
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* another object, known as its target. The target can be an arbitrary JS
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* object. Not every proxy has the notion of a target, however.
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*
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* To minimize code duplication, a set of abstract proxy handler classes is
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* provided, from which other handlers may inherit. These abstract classes are
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* organized in the following hierarchy:
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*
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* BaseProxyHandler
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* |
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* DirectProxyHandler // has a target
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* |
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* Wrapper // can be unwrapped, revealing target
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* | // (see js::CheckedUnwrap)
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* |
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* CrossCompartmentWrapper // target is in another compartment;
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* // implements membrane between compartments
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*
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* Example: Some DOM objects (including all the arraylike DOM objects) are
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* implemented as proxies. Since these objects don't need to forward operations
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* to any underlying JS object, DOMJSProxyHandler directly subclasses
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* BaseProxyHandler.
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*
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* Gecko's security wrappers are examples of cross-compartment wrappers.
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*
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* ### Proxy prototype chains
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*
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* In addition to the normal methods, there are two models for proxy prototype
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* chains.
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*
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* 1. Proxies can use the standard prototype mechanism used throughout the
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* engine. To do so, simply pass a prototype to NewProxyObject() at
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* creation time. All prototype accesses will then "just work" to treat the
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* proxy as a "normal" object.
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*
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* 2. A proxy can implement more complicated prototype semantics (if, for
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* example, it wants to delegate the prototype lookup to a wrapped object)
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* by passing Proxy::LazyProto as the prototype at create time. This
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* guarantees that the getPrototype() handler method will be called every
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* time the object's prototype chain is accessed.
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*
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* This system is implemented with two methods: {get,set}Prototype. The
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* default implementation of setPrototype throws a TypeError. Since it is
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* not possible to create an object without a sense of prototype chain,
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* handlers must implement getPrototype if opting in to the dynamic
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* prototype system.
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*/
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/*
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* BaseProxyHandler is the most generic kind of proxy handler. It does not make
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* any assumptions about the target. Consequently, it does not provide any
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* default implementation for most methods. As a convenience, a few high-level
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* methods, like get() and set(), are given default implementations that work by
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* calling the low-level methods, like getOwnPropertyDescriptor().
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*
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* Important: If you add a method here, you should probably also add a
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* Proxy::foo entry point with an AutoEnterPolicy. If you don't, you need an
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* explicit override for the method in SecurityWrapper. See bug 945826 comment 0.
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*/
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class JS_FRIEND_API(BaseProxyHandler)
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{
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/*
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* Sometimes it's desirable to designate groups of proxy handlers as "similar".
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* For this, we use the notion of a "family": A consumer-provided opaque pointer
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* that designates the larger group to which this proxy belongs.
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*
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* If it will never be important to differentiate this proxy from others as
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* part of a distinct group, nullptr may be used instead.
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*/
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const void *mFamily;
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/*
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* Proxy handlers can use mHasPrototype to request the following special
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* treatment from the JS engine:
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*
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* - When mHasPrototype is true, the engine never calls these methods:
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* getPropertyDescriptor, has, set, enumerate, iterate. Instead, for
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* these operations, it calls the "own" methods like
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* getOwnPropertyDescriptor, hasOwn, defineProperty,
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* getOwnEnumerablePropertyKeys, etc., and consults the prototype chain
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* if needed.
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*
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* - When mHasPrototype is true, the engine calls handler->get() only if
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* handler->hasOwn() says an own property exists on the proxy. If not,
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* it consults the prototype chain.
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*
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* This is useful because it frees the ProxyHandler from having to implement
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* any behavior having to do with the prototype chain.
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*/
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bool mHasPrototype;
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/*
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* All proxies indicate whether they have any sort of interesting security
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* policy that might prevent the caller from doing something it wants to
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* the object. In the case of wrappers, this distinction is used to
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* determine whether the caller may strip off the wrapper if it so desires.
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*/
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bool mHasSecurityPolicy;
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public:
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explicit MOZ_CONSTEXPR BaseProxyHandler(const void *aFamily, bool aHasPrototype = false,
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bool aHasSecurityPolicy = false)
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: mFamily(aFamily),
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mHasPrototype(aHasPrototype),
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mHasSecurityPolicy(aHasSecurityPolicy)
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{ }
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bool hasPrototype() const {
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return mHasPrototype;
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}
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bool hasSecurityPolicy() const {
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return mHasSecurityPolicy;
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}
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inline const void *family() const {
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return mFamily;
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}
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static size_t offsetOfFamily() {
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return offsetof(BaseProxyHandler, mFamily);
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}
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virtual bool finalizeInBackground(Value priv) const {
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/*
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* Called on creation of a proxy to determine whether its finalize
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* method can be finalized on the background thread.
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*/
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return true;
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}
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/* Policy enforcement methods.
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*
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* enter() allows the policy to specify whether the caller may perform |act|
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* on the proxy's |id| property. In the case when |act| is CALL, |id| is
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* generally JSID_VOID.
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*
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* The |act| parameter to enter() specifies the action being performed.
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* If |bp| is false, the method suggests that the caller throw (though it
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* may still decide to squelch the error).
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*
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* We make these OR-able so that assertEnteredPolicy can pass a union of them.
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* For example, get{,Own}PropertyDescriptor is invoked by calls to ::get()
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* ::set(), in addition to being invoked on its own, so there are several
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* valid Actions that could have been entered.
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*/
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typedef uint32_t Action;
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enum {
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NONE = 0x00,
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GET = 0x01,
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SET = 0x02,
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CALL = 0x04,
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ENUMERATE = 0x08,
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GET_PROPERTY_DESCRIPTOR = 0x10
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};
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virtual bool enter(JSContext *cx, HandleObject wrapper, HandleId id, Action act,
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bool *bp) const;
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/* Standard internal methods. */
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virtual bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
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MutableHandle<JSPropertyDescriptor> desc) const = 0;
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virtual bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
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MutableHandle<JSPropertyDescriptor> desc,
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ObjectOpResult &result) const = 0;
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virtual bool ownPropertyKeys(JSContext *cx, HandleObject proxy,
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AutoIdVector &props) const = 0;
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virtual bool delete_(JSContext *cx, HandleObject proxy, HandleId id,
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ObjectOpResult &result) const = 0;
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/*
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* Because [[Enumerate]] is one of the standard traps it should be overridden.
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* However for convenience BaseProxyHandler includes a pure virtual implementation,
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* that turns the properties returned by getOwnEnumerablePropertyKeys (and proto walking)
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* into an Iterator object.
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*/
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virtual bool enumerate(JSContext *cx, HandleObject proxy, MutableHandleObject objp) const = 0;
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/*
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* These methods are standard, but the engine does not normally call them.
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* They're opt-in. See "Proxy prototype chains" above.
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*
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* getPrototype() crashes if called. setPrototype() throws a TypeError.
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*/
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virtual bool getPrototype(JSContext *cx, HandleObject proxy, MutableHandleObject protop) const;
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virtual bool setPrototype(JSContext *cx, HandleObject proxy, HandleObject proto,
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ObjectOpResult &result) const;
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/* Non-standard but conceptual kin to {g,s}etPrototype, so lives here. */
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virtual bool setImmutablePrototype(JSContext *cx, HandleObject proxy, bool *succeeded) const;
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virtual bool preventExtensions(JSContext *cx, HandleObject proxy,
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ObjectOpResult &result) const = 0;
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virtual bool isExtensible(JSContext *cx, HandleObject proxy, bool *extensible) const = 0;
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/*
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* These standard internal methods are implemented, as a convenience, so
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* that ProxyHandler subclasses don't have to provide every single method.
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*
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* The base-class implementations work by calling getPropertyDescriptor().
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* They do not follow any standard. When in doubt, override them.
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*/
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virtual bool has(JSContext *cx, HandleObject proxy, HandleId id, bool *bp) const;
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virtual bool get(JSContext *cx, HandleObject proxy, HandleObject receiver,
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HandleId id, MutableHandleValue vp) const;
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virtual bool set(JSContext *cx, HandleObject proxy, HandleObject receiver,
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HandleId id, MutableHandleValue vp, ObjectOpResult &result) const;
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/*
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* [[Call]] and [[Construct]] are standard internal methods but according
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* to the spec, they are not present on every object.
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*
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* SpiderMonkey never calls a proxy's call()/construct() internal method
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* unless isCallable()/isConstructor() returns true for that proxy.
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*
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* BaseProxyHandler::isCallable()/isConstructor() always return false, and
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* BaseProxyHandler::call()/construct() crash if called. So if you're
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* creating a kind of that is never callable, you don't have to override
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* anything, but otherwise you probably want to override all four.
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*/
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virtual bool call(JSContext *cx, HandleObject proxy, const CallArgs &args) const;
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virtual bool construct(JSContext *cx, HandleObject proxy, const CallArgs &args) const;
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/* SpiderMonkey extensions. */
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virtual bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
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MutableHandle<JSPropertyDescriptor> desc) const = 0;
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virtual bool hasOwn(JSContext *cx, HandleObject proxy, HandleId id, bool *bp) const;
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virtual bool getOwnEnumerablePropertyKeys(JSContext *cx, HandleObject proxy,
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AutoIdVector &props) const;
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virtual bool nativeCall(JSContext *cx, IsAcceptableThis test, NativeImpl impl, CallArgs args) const;
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virtual bool hasInstance(JSContext *cx, HandleObject proxy, MutableHandleValue v, bool *bp) const;
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virtual bool objectClassIs(HandleObject obj, ESClassValue classValue, JSContext *cx) const;
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virtual const char *className(JSContext *cx, HandleObject proxy) const;
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virtual JSString *fun_toString(JSContext *cx, HandleObject proxy, unsigned indent) const;
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virtual bool regexp_toShared(JSContext *cx, HandleObject proxy, RegExpGuard *g) const;
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virtual bool boxedValue_unbox(JSContext *cx, HandleObject proxy, MutableHandleValue vp) const;
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virtual bool defaultValue(JSContext *cx, HandleObject obj, JSType hint, MutableHandleValue vp) const;
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virtual void trace(JSTracer *trc, JSObject *proxy) const;
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virtual void finalize(JSFreeOp *fop, JSObject *proxy) const;
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virtual void objectMoved(JSObject *proxy, const JSObject *old) const;
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// Allow proxies, wrappers in particular, to specify callability at runtime.
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// Note: These do not take const JSObject *, but they do in spirit.
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// We are not prepared to do this, as there's little const correctness
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// in the external APIs that handle proxies.
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virtual bool isCallable(JSObject *obj) const;
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virtual bool isConstructor(JSObject *obj) const;
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// These two hooks must be overridden, or not overridden, in tandem -- no
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// overriding just one!
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virtual bool watch(JSContext *cx, JS::HandleObject proxy, JS::HandleId id,
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JS::HandleObject callable) const;
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virtual bool unwatch(JSContext *cx, JS::HandleObject proxy, JS::HandleId id) const;
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virtual bool getElements(JSContext *cx, HandleObject proxy, uint32_t begin, uint32_t end,
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ElementAdder *adder) const;
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/* See comment for weakmapKeyDelegateOp in js/Class.h. */
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virtual JSObject *weakmapKeyDelegate(JSObject *proxy) const;
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virtual bool isScripted() const { return false; }
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};
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/*
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* DirectProxyHandler includes a notion of a target object. All methods are
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* reimplemented such that they forward their behavior to the target. This
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* allows consumers of this class to forward to another object as transparently
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* and efficiently as possible.
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*
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* Important: If you add a method implementation here, you probably also need
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* to add an override in CrossCompartmentWrapper. If you don't, you risk
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* compartment mismatches. See bug 945826 comment 0.
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*/
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class JS_FRIEND_API(DirectProxyHandler) : public BaseProxyHandler
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{
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public:
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explicit MOZ_CONSTEXPR DirectProxyHandler(const void *aFamily, bool aHasPrototype = false,
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bool aHasSecurityPolicy = false)
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: BaseProxyHandler(aFamily, aHasPrototype, aHasSecurityPolicy)
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{ }
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/* Standard internal methods. */
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virtual bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
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MutableHandle<JSPropertyDescriptor> desc) const override;
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virtual bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
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MutableHandle<JSPropertyDescriptor> desc,
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ObjectOpResult &result) const override;
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virtual bool ownPropertyKeys(JSContext *cx, HandleObject proxy,
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AutoIdVector &props) const override;
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virtual bool delete_(JSContext *cx, HandleObject proxy, HandleId id,
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ObjectOpResult &result) const override;
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virtual bool enumerate(JSContext *cx, HandleObject proxy,
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MutableHandleObject objp) const override;
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virtual bool getPrototype(JSContext *cx, HandleObject proxy,
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MutableHandleObject protop) const override;
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virtual bool setPrototype(JSContext *cx, HandleObject proxy, HandleObject proto,
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ObjectOpResult &result) const override;
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virtual bool setImmutablePrototype(JSContext *cx, HandleObject proxy,
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bool *succeeded) const override;
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virtual bool preventExtensions(JSContext *cx, HandleObject proxy,
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ObjectOpResult &result) const override;
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virtual bool isExtensible(JSContext *cx, HandleObject proxy, bool *extensible) const override;
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virtual bool has(JSContext *cx, HandleObject proxy, HandleId id,
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bool *bp) const override;
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virtual bool get(JSContext *cx, HandleObject proxy, HandleObject receiver,
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HandleId id, MutableHandleValue vp) const override;
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virtual bool set(JSContext *cx, HandleObject proxy, HandleObject receiver,
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HandleId id, MutableHandleValue vp,
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ObjectOpResult &result) const override;
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virtual bool call(JSContext *cx, HandleObject proxy, const CallArgs &args) const override;
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virtual bool construct(JSContext *cx, HandleObject proxy, const CallArgs &args) const override;
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/* SpiderMonkey extensions. */
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virtual bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
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MutableHandle<JSPropertyDescriptor> desc) const override;
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virtual bool hasOwn(JSContext *cx, HandleObject proxy, HandleId id,
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bool *bp) const override;
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virtual bool getOwnEnumerablePropertyKeys(JSContext *cx, HandleObject proxy,
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AutoIdVector &props) const override;
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virtual bool nativeCall(JSContext *cx, IsAcceptableThis test, NativeImpl impl,
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CallArgs args) const override;
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virtual bool hasInstance(JSContext *cx, HandleObject proxy, MutableHandleValue v,
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bool *bp) const override;
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virtual bool objectClassIs(HandleObject obj, ESClassValue classValue,
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JSContext *cx) const override;
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virtual const char *className(JSContext *cx, HandleObject proxy) const override;
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virtual JSString *fun_toString(JSContext *cx, HandleObject proxy,
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unsigned indent) const override;
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virtual bool regexp_toShared(JSContext *cx, HandleObject proxy,
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RegExpGuard *g) const override;
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virtual bool boxedValue_unbox(JSContext *cx, HandleObject proxy, MutableHandleValue vp) const override;
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virtual bool isCallable(JSObject *obj) const override;
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virtual JSObject *weakmapKeyDelegate(JSObject *proxy) const override;
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};
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extern JS_FRIEND_DATA(const js::Class* const) ProxyClassPtr;
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inline bool IsProxy(JSObject *obj)
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{
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return GetObjectClass(obj)->isProxy();
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}
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const uint32_t PROXY_EXTRA_SLOTS = 2;
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// Layout of the values stored by a proxy. Note that API clients require the
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// private slot to be the first slot in the proxy's values, so that the private
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// slot can be accessed in the same fashion as the first reserved slot, via
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// {Get,Set}ReservedOrProxyPrivateSlot.
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struct ProxyValueArray
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{
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Value privateSlot;
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Value extraSlots[PROXY_EXTRA_SLOTS];
|
|
|
|
ProxyValueArray()
|
|
: privateSlot(JS::UndefinedValue())
|
|
{
|
|
for (size_t i = 0; i < PROXY_EXTRA_SLOTS; i++)
|
|
extraSlots[i] = JS::UndefinedValue();
|
|
}
|
|
};
|
|
|
|
// All proxies share the same data layout. Following the object's shape and
|
|
// type, the proxy has a ProxyDataLayout structure with a pointer to an array
|
|
// of values and the proxy's handler. This is designed both so that proxies can
|
|
// be easily swapped with other objects (via RemapWrapper) and to mimic the
|
|
// layout of other objects (proxies and other objects have the same size) so
|
|
// that common code can access either type of object.
|
|
//
|
|
// See GetReservedOrProxyPrivateSlot below.
|
|
struct ProxyDataLayout
|
|
{
|
|
ProxyValueArray *values;
|
|
const BaseProxyHandler *handler;
|
|
};
|
|
|
|
const uint32_t ProxyDataOffset = 2 * sizeof(void *);
|
|
|
|
// This method should only be used internally and by the accessors below.
|
|
inline ProxyDataLayout *
|
|
GetProxyDataLayout(JSObject *obj)
|
|
{
|
|
MOZ_ASSERT(IsProxy(obj));
|
|
return reinterpret_cast<ProxyDataLayout *>(reinterpret_cast<uint8_t *>(obj) + ProxyDataOffset);
|
|
}
|
|
|
|
inline const BaseProxyHandler *
|
|
GetProxyHandler(JSObject *obj)
|
|
{
|
|
return GetProxyDataLayout(obj)->handler;
|
|
}
|
|
|
|
inline const Value &
|
|
GetProxyPrivate(JSObject *obj)
|
|
{
|
|
return GetProxyDataLayout(obj)->values->privateSlot;
|
|
}
|
|
|
|
inline JSObject *
|
|
GetProxyTargetObject(JSObject *obj)
|
|
{
|
|
return GetProxyPrivate(obj).toObjectOrNull();
|
|
}
|
|
|
|
inline const Value &
|
|
GetProxyExtra(JSObject *obj, size_t n)
|
|
{
|
|
MOZ_ASSERT(n < PROXY_EXTRA_SLOTS);
|
|
return GetProxyDataLayout(obj)->values->extraSlots[n];
|
|
}
|
|
|
|
inline void
|
|
SetProxyHandler(JSObject *obj, const BaseProxyHandler *handler)
|
|
{
|
|
GetProxyDataLayout(obj)->handler = handler;
|
|
}
|
|
|
|
JS_FRIEND_API(void)
|
|
SetValueInProxy(Value *slot, const Value &value);
|
|
|
|
inline void
|
|
SetProxyExtra(JSObject *obj, size_t n, const Value &extra)
|
|
{
|
|
MOZ_ASSERT(n < PROXY_EXTRA_SLOTS);
|
|
Value *vp = &GetProxyDataLayout(obj)->values->extraSlots[n];
|
|
|
|
// Trigger a barrier before writing the slot.
|
|
if (vp->isMarkable() || extra.isMarkable())
|
|
SetValueInProxy(vp, extra);
|
|
else
|
|
*vp = extra;
|
|
}
|
|
|
|
inline bool
|
|
IsScriptedProxy(JSObject *obj)
|
|
{
|
|
return IsProxy(obj) && GetProxyHandler(obj)->isScripted();
|
|
}
|
|
|
|
inline const Value &
|
|
GetReservedOrProxyPrivateSlot(JSObject *obj, size_t slot)
|
|
{
|
|
MOZ_ASSERT(slot == 0);
|
|
MOZ_ASSERT(slot < JSCLASS_RESERVED_SLOTS(GetObjectClass(obj)) || IsProxy(obj));
|
|
return reinterpret_cast<const shadow::Object *>(obj)->slotRef(slot);
|
|
}
|
|
|
|
inline void
|
|
SetReservedOrProxyPrivateSlot(JSObject *obj, size_t slot, const Value &value)
|
|
{
|
|
MOZ_ASSERT(slot == 0);
|
|
MOZ_ASSERT(slot < JSCLASS_RESERVED_SLOTS(GetObjectClass(obj)) || IsProxy(obj));
|
|
shadow::Object *sobj = reinterpret_cast<shadow::Object *>(obj);
|
|
if (sobj->slotRef(slot).isMarkable() || value.isMarkable())
|
|
SetReservedOrProxyPrivateSlotWithBarrier(obj, slot, value);
|
|
else
|
|
sobj->slotRef(slot) = value;
|
|
}
|
|
|
|
class MOZ_STACK_CLASS ProxyOptions {
|
|
protected:
|
|
/* protected constructor for subclass */
|
|
explicit ProxyOptions(bool singletonArg, bool lazyProtoArg = false)
|
|
: singleton_(singletonArg),
|
|
lazyProto_(lazyProtoArg),
|
|
clasp_(ProxyClassPtr)
|
|
{}
|
|
|
|
public:
|
|
ProxyOptions() : singleton_(false),
|
|
lazyProto_(false),
|
|
clasp_(ProxyClassPtr)
|
|
{}
|
|
|
|
bool singleton() const { return singleton_; }
|
|
ProxyOptions &setSingleton(bool flag) {
|
|
singleton_ = flag;
|
|
return *this;
|
|
}
|
|
|
|
bool lazyProto() const { return lazyProto_; }
|
|
ProxyOptions &setLazyProto(bool flag) {
|
|
lazyProto_ = flag;
|
|
return *this;
|
|
}
|
|
|
|
const Class *clasp() const {
|
|
return clasp_;
|
|
}
|
|
ProxyOptions &setClass(const Class *claspArg) {
|
|
clasp_ = claspArg;
|
|
return *this;
|
|
}
|
|
|
|
private:
|
|
bool singleton_;
|
|
bool lazyProto_;
|
|
const Class *clasp_;
|
|
};
|
|
|
|
JS_FRIEND_API(JSObject *)
|
|
NewProxyObject(JSContext *cx, const BaseProxyHandler *handler, HandleValue priv,
|
|
JSObject *proto, const ProxyOptions &options = ProxyOptions());
|
|
|
|
JSObject *
|
|
RenewProxyObject(JSContext *cx, JSObject *obj, BaseProxyHandler *handler, Value priv);
|
|
|
|
class JS_FRIEND_API(AutoEnterPolicy)
|
|
{
|
|
public:
|
|
typedef BaseProxyHandler::Action Action;
|
|
AutoEnterPolicy(JSContext *cx, const BaseProxyHandler *handler,
|
|
HandleObject wrapper, HandleId id, Action act, bool mayThrow)
|
|
#ifdef JS_DEBUG
|
|
: context(nullptr)
|
|
#endif
|
|
{
|
|
allow = handler->hasSecurityPolicy() ? handler->enter(cx, wrapper, id, act, &rv)
|
|
: true;
|
|
recordEnter(cx, wrapper, id, act);
|
|
// We want to throw an exception if all of the following are true:
|
|
// * The policy disallowed access.
|
|
// * The policy set rv to false, indicating that we should throw.
|
|
// * The caller did not instruct us to ignore exceptions.
|
|
// * The policy did not throw itself.
|
|
if (!allow && !rv && mayThrow)
|
|
reportErrorIfExceptionIsNotPending(cx, id);
|
|
}
|
|
|
|
virtual ~AutoEnterPolicy() { recordLeave(); }
|
|
inline bool allowed() { return allow; }
|
|
inline bool returnValue() { MOZ_ASSERT(!allowed()); return rv; }
|
|
|
|
protected:
|
|
// no-op constructor for subclass
|
|
AutoEnterPolicy()
|
|
#ifdef JS_DEBUG
|
|
: context(nullptr)
|
|
, enteredAction(BaseProxyHandler::NONE)
|
|
#endif
|
|
{}
|
|
void reportErrorIfExceptionIsNotPending(JSContext *cx, jsid id);
|
|
bool allow;
|
|
bool rv;
|
|
|
|
#ifdef JS_DEBUG
|
|
JSContext *context;
|
|
mozilla::Maybe<HandleObject> enteredProxy;
|
|
mozilla::Maybe<HandleId> enteredId;
|
|
Action enteredAction;
|
|
|
|
// NB: We explicitly don't track the entered action here, because sometimes
|
|
// set() methods do an implicit get() during their implementation, leading
|
|
// to spurious assertions.
|
|
AutoEnterPolicy *prev;
|
|
void recordEnter(JSContext *cx, HandleObject proxy, HandleId id, Action act);
|
|
void recordLeave();
|
|
|
|
friend JS_FRIEND_API(void) assertEnteredPolicy(JSContext *cx, JSObject *proxy, jsid id, Action act);
|
|
#else
|
|
inline void recordEnter(JSContext *cx, JSObject *proxy, jsid id, Action act) {}
|
|
inline void recordLeave() {}
|
|
#endif
|
|
|
|
};
|
|
|
|
#ifdef JS_DEBUG
|
|
class JS_FRIEND_API(AutoWaivePolicy) : public AutoEnterPolicy {
|
|
public:
|
|
AutoWaivePolicy(JSContext *cx, HandleObject proxy, HandleId id,
|
|
BaseProxyHandler::Action act)
|
|
{
|
|
allow = true;
|
|
recordEnter(cx, proxy, id, act);
|
|
}
|
|
};
|
|
#else
|
|
class JS_FRIEND_API(AutoWaivePolicy) {
|
|
public:
|
|
AutoWaivePolicy(JSContext *cx, HandleObject proxy, HandleId id,
|
|
BaseProxyHandler::Action act)
|
|
{}
|
|
};
|
|
#endif
|
|
|
|
#ifdef JS_DEBUG
|
|
extern JS_FRIEND_API(void)
|
|
assertEnteredPolicy(JSContext *cx, JSObject *obj, jsid id,
|
|
BaseProxyHandler::Action act);
|
|
#else
|
|
inline void assertEnteredPolicy(JSContext *cx, JSObject *obj, jsid id,
|
|
BaseProxyHandler::Action act)
|
|
{}
|
|
#endif
|
|
|
|
extern JS_FRIEND_API(JSObject *)
|
|
InitProxyClass(JSContext *cx, JS::HandleObject obj);
|
|
|
|
} /* namespace js */
|
|
|
|
#endif /* js_Proxy_h */
|