michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef jscompartmentinlines_h
michael@0: #define jscompartmentinlines_h
michael@0: 
michael@0: #include "jscompartment.h"
michael@0: 
michael@0: #include "gc/Barrier-inl.h"
michael@0: 
michael@0: inline void
michael@0: JSCompartment::initGlobal(js::GlobalObject &global)
michael@0: {
michael@0:     JS_ASSERT(global.compartment() == this);
michael@0:     JS_ASSERT(!global_);
michael@0:     global_ = &global;
michael@0: }
michael@0: 
michael@0: js::GlobalObject *
michael@0: JSCompartment::maybeGlobal() const
michael@0: {
michael@0:     JS_ASSERT_IF(global_, global_->compartment() == this);
michael@0:     return global_;
michael@0: }
michael@0: 
michael@0: js::AutoCompartment::AutoCompartment(ExclusiveContext *cx, JSObject *target)
michael@0:   : cx_(cx),
michael@0:     origin_(cx->compartment_)
michael@0: {
michael@0:     cx_->enterCompartment(target->compartment());
michael@0: }
michael@0: 
michael@0: js::AutoCompartment::AutoCompartment(ExclusiveContext *cx, JSCompartment *target)
michael@0:   : cx_(cx),
michael@0:     origin_(cx_->compartment_)
michael@0: {
michael@0:     cx_->enterCompartment(target);
michael@0: }
michael@0: 
michael@0: js::AutoCompartment::~AutoCompartment()
michael@0: {
michael@0:     cx_->leaveCompartment(origin_);
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: JSCompartment::wrap(JSContext *cx, JS::MutableHandleValue vp, JS::HandleObject existing)
michael@0: {
michael@0:     JS_ASSERT_IF(existing, vp.isObject());
michael@0: 
michael@0:     /* Only GC things have to be wrapped or copied. */
michael@0:     if (!vp.isMarkable())
michael@0:         return true;
michael@0: 
michael@0:     /* Handle strings. */
michael@0:     if (vp.isString()) {
michael@0:         JS::RootedString str(cx, vp.toString());
michael@0:         if (!wrap(cx, str.address()))
michael@0:             return false;
michael@0:         vp.setString(str);
michael@0:         return true;
michael@0:     }
michael@0: 
michael@0:     JS_ASSERT(vp.isObject());
michael@0: 
michael@0:     /*
michael@0:      * All that's left are objects.
michael@0:      *
michael@0:      * Object wrapping isn't the fastest thing in the world, in part because
michael@0:      * we have to unwrap and invoke the prewrap hook to find the identity
michael@0:      * object before we even start checking the cache. Neither of these
michael@0:      * operations are needed in the common case, where we're just wrapping
michael@0:      * a plain JS object from the wrappee's side of the membrane to the
michael@0:      * wrapper's side.
michael@0:      *
michael@0:      * To optimize this, we note that the cache should only ever contain
michael@0:      * identity objects - that is to say, objects that serve as the
michael@0:      * canonical representation for a unique object identity observable by
michael@0:      * script. Unwrap and prewrap are both steps that we take to get to the
michael@0:      * identity of an incoming objects, and as such, they shuld never map
michael@0:      * one identity object to another object. This means that we can safely
michael@0:      * check the cache immediately, and only risk false negatives. Do this
michael@0:      * in opt builds, and do both in debug builds so that we can assert
michael@0:      * that we get the same answer.
michael@0:      */
michael@0: #ifdef DEBUG
michael@0:     JS::RootedObject cacheResult(cx);
michael@0: #endif
michael@0:     JS::RootedValue v(cx, vp);
michael@0:     if (js::WrapperMap::Ptr p = crossCompartmentWrappers.lookup(v)) {
michael@0: #ifdef DEBUG
michael@0:         cacheResult = &p->value().get().toObject();
michael@0: #else
michael@0:         vp.set(p->value());
michael@0:         return true;
michael@0: #endif
michael@0:     }
michael@0: 
michael@0:     JS::RootedObject obj(cx, &vp.toObject());
michael@0:     if (!wrap(cx, &obj, existing))
michael@0:         return false;
michael@0:     vp.setObject(*obj);
michael@0:     JS_ASSERT_IF(cacheResult, obj == cacheResult);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: #endif /* jscompartmentinlines_h */