gecko-dev/dom/base/StructuredCloneBlob.cpp
Kris Maglione 8683b183cd Bug 1382645: Part 1 - Add memory reporter for StructuredCloneHolder binding implementation. r=billm
MozReview-Commit-ID: aK3ljfCJVi

--HG--
extra : rebase_source : d788c6c686cc72b423ca100795a379d343c398db
2017-07-25 14:53:41 -07:00

206 lines
5.6 KiB
C++

/* -*- 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/. */
#include "mozilla/dom/StructuredCloneBlob.h"
#include "js/StructuredClone.h"
#include "js/Utility.h"
#include "jswrapper.h"
#include "xpcpublic.h"
#include "mozilla/Maybe.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/dom/StructuredCloneTags.h"
namespace mozilla {
namespace dom {
StructuredCloneBlob::StructuredCloneBlob()
: StructuredCloneHolder(CloningSupported, TransferringNotSupported,
StructuredCloneScope::DifferentProcess)
{}
StructuredCloneBlob::~StructuredCloneBlob()
{
UnregisterWeakMemoryReporter(this);
}
/* static */ already_AddRefed<StructuredCloneBlob>
StructuredCloneBlob::Constructor(GlobalObject& aGlobal, JS::HandleValue aValue,
JS::HandleObject aTargetGlobal,
ErrorResult& aRv)
{
JSContext* cx = aGlobal.Context();
RefPtr<StructuredCloneBlob> holder = StructuredCloneBlob::Create();
Maybe<JSAutoCompartment> ac;
JS::RootedValue value(cx, aValue);
if (aTargetGlobal) {
JS::RootedObject targetGlobal(cx, js::CheckedUnwrap(aTargetGlobal));
if (!targetGlobal) {
js::ReportAccessDenied(cx);
aRv.NoteJSContextException(cx);
return nullptr;
}
ac.emplace(cx, targetGlobal);
if (!JS_WrapValue(cx, &value)) {
aRv.NoteJSContextException(cx);
return nullptr;
}
} else if (value.isObject()) {
JS::RootedObject obj(cx, js::CheckedUnwrap(&value.toObject()));
if (!obj) {
js::ReportAccessDenied(cx);
aRv.NoteJSContextException(cx);
return nullptr;
}
ac.emplace(cx, obj);
value = JS::ObjectValue(*obj);
}
holder->Write(cx, value, aRv);
if (aRv.Failed()) {
return nullptr;
}
return holder.forget();
}
void
StructuredCloneBlob::Deserialize(JSContext* aCx, JS::HandleObject aTargetScope,
JS::MutableHandleValue aResult, ErrorResult& aRv)
{
JS::RootedObject scope(aCx, js::CheckedUnwrap(aTargetScope));
if (!scope) {
js::ReportAccessDenied(aCx);
aRv.NoteJSContextException(aCx);
return;
}
{
JSAutoCompartment ac(aCx, scope);
Read(xpc::NativeGlobal(scope), aCx, aResult, aRv);
if (aRv.Failed()) {
return;
}
}
if (!JS_WrapValue(aCx, aResult)) {
aResult.set(JS::UndefinedValue());
aRv.NoteJSContextException(aCx);
}
}
/* static */ JSObject*
StructuredCloneBlob::ReadStructuredClone(JSContext* aCx, JSStructuredCloneReader* aReader,
StructuredCloneHolder* aHolder)
{
JS::RootedObject obj(aCx);
{
RefPtr<StructuredCloneBlob> holder = StructuredCloneBlob::Create();
if (!holder->ReadStructuredCloneInternal(aCx, aReader, aHolder) ||
!holder->WrapObject(aCx, nullptr, &obj)) {
return nullptr;
}
}
return obj.get();
}
bool
StructuredCloneBlob::ReadStructuredCloneInternal(JSContext* aCx, JSStructuredCloneReader* aReader,
StructuredCloneHolder* aHolder)
{
uint32_t length;
uint32_t version;
if (!JS_ReadUint32Pair(aReader, &length, &version)) {
return false;
}
uint32_t blobOffset;
uint32_t blobCount;
if (!JS_ReadUint32Pair(aReader, &blobOffset, &blobCount)) {
return false;
}
if (blobCount) {
BlobImpls().AppendElements(&aHolder->BlobImpls()[blobOffset], blobCount);
}
JSStructuredCloneData data;
while (length) {
size_t size;
char* buffer = data.AllocateBytes(length, &size);
if (!buffer || !JS_ReadBytes(aReader, buffer, size)) {
return false;
}
length -= size;
}
mBuffer = MakeUnique<JSAutoStructuredCloneBuffer>(mStructuredCloneScope,
&StructuredCloneHolder::sCallbacks,
this);
mBuffer->adopt(Move(data), version, &StructuredCloneHolder::sCallbacks);
return true;
}
bool
StructuredCloneBlob::WriteStructuredClone(JSContext* aCx, JSStructuredCloneWriter* aWriter,
StructuredCloneHolder* aHolder)
{
auto& data = mBuffer->data();
if (!JS_WriteUint32Pair(aWriter, SCTAG_DOM_STRUCTURED_CLONE_HOLDER, 0) ||
!JS_WriteUint32Pair(aWriter, data.Size(), JS_STRUCTURED_CLONE_VERSION) ||
!JS_WriteUint32Pair(aWriter, aHolder->BlobImpls().Length(), BlobImpls().Length())) {
return false;
}
aHolder->BlobImpls().AppendElements(BlobImpls());
auto iter = data.Iter();
while (!iter.Done()) {
if (!JS_WriteBytes(aWriter, iter.Data(), iter.RemainingInSegment())) {
return false;
}
iter.Advance(data, iter.RemainingInSegment());
}
return true;
}
bool
StructuredCloneBlob::WrapObject(JSContext* aCx, JS::HandleObject aGivenProto, JS::MutableHandleObject aResult)
{
return StructuredCloneHolderBinding::Wrap(aCx, this, aGivenProto, aResult);
}
NS_IMETHODIMP
StructuredCloneBlob::CollectReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData, bool aAnonymize)
{
MOZ_COLLECT_REPORT(
"explicit/dom/structured-clone-holder", KIND_HEAP, UNITS_BYTES,
MallocSizeOf(this) + SizeOfExcludingThis(MallocSizeOf),
"Memory used by StructuredCloneHolder DOM objects.");
return NS_OK;
}
NS_IMPL_ISUPPORTS(StructuredCloneBlob, nsIMemoryReporter)
} // namespace dom
} // namespace mozilla