gecko-dev/js/ipc/JavaScriptChild.cpp

101 lines
2.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=4 sw=4 et 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/. */
#include "JavaScriptChild.h"
#include "mozilla/dom/ContentChild.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/ipc/MessageChannel.h"
#include "nsContentUtils.h"
#include "xpcprivate.h"
#include "jsfriendapi.h"
#include "AccessCheck.h"
using namespace JS;
using namespace mozilla;
using namespace mozilla::jsipc;
using mozilla::AutoSafeJSContext;
static void
UpdateChildWeakPointersBeforeSweepingZoneGroup(JSContext* cx, void* data)
{
static_cast<JavaScriptChild*>(data)->updateWeakPointers();
}
static void
TraceChild(JSTracer* trc, void* data)
{
static_cast<JavaScriptChild*>(data)->trace(trc);
}
JavaScriptChild::~JavaScriptChild()
{
JSContext* cx = dom::danger::GetJSContext();
JS_RemoveWeakPointerZonesCallback(cx, UpdateChildWeakPointersBeforeSweepingZoneGroup);
JS_RemoveExtraGCRootsTracer(cx, TraceChild, this);
}
bool
JavaScriptChild::init()
{
if (!WrapperOwner::init())
return false;
if (!WrapperAnswer::init())
return false;
JSContext* cx = dom::danger::GetJSContext();
JS_AddWeakPointerZonesCallback(cx, UpdateChildWeakPointersBeforeSweepingZoneGroup, this);
JS_AddExtraGCRootsTracer(cx, TraceChild, this);
return true;
}
void
JavaScriptChild::trace(JSTracer* trc)
{
objects_.trace(trc, strongReferenceObjIdMinimum_);
}
void
JavaScriptChild::updateWeakPointers()
{
objects_.sweep();
unwaivedObjectIds_.sweep();
waivedObjectIds_.sweep();
}
JSObject*
JavaScriptChild::scopeForTargetObjects()
{
// CPOWs from the parent need to point into the child's privileged junk
// scope so that they can benefit from XrayWrappers in the child.
return xpc::PrivilegedJunkScope();
}
mozilla::ipc::IPCResult
JavaScriptChild::RecvDropTemporaryStrongReferences(const uint64_t& upToObjId)
{
strongReferenceObjIdMinimum_ = upToObjId + 1;
return IPC_OK();
}
PJavaScriptChild*
mozilla::jsipc::NewJavaScriptChild()
{
JavaScriptChild* child = new JavaScriptChild();
if (!child->init()) {
delete child;
return nullptr;
}
return child;
}
void
mozilla::jsipc::ReleaseJavaScriptChild(PJavaScriptChild* child)
{
static_cast<JavaScriptChild*>(child)->decref();
}