gecko/dom/base/StructuredCloneHelper.cpp

904 lines
26 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 "StructuredCloneHelper.h"
#include "ImageContainer.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/dom/BlobBinding.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/FileList.h"
#include "mozilla/dom/FileListBinding.h"
#include "mozilla/dom/ImageBitmap.h"
#include "mozilla/dom/ImageBitmapBinding.h"
#include "mozilla/dom/ImageData.h"
#include "mozilla/dom/ImageDataBinding.h"
#include "mozilla/dom/ipc/BlobChild.h"
#include "mozilla/dom/StructuredClone.h"
#include "mozilla/dom/MessagePort.h"
#include "mozilla/dom/MessagePortBinding.h"
#include "mozilla/dom/PMessagePort.h"
#include "mozilla/dom/StructuredCloneTags.h"
#include "mozilla/dom/ToJSValue.h"
#include "mozilla/dom/WebCryptoCommon.h"
#include "mozilla/ipc/BackgroundChild.h"
#include "mozilla/ipc/BackgroundUtils.h"
#include "MultipartBlobImpl.h"
#include "nsFormData.h"
#include "nsIRemoteBlob.h"
#include "nsQueryObject.h"
using namespace mozilla::ipc;
namespace mozilla {
namespace dom {
namespace {
JSObject*
StructuredCloneCallbacksRead(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aTag, uint32_t aIndex,
void* aClosure)
{
StructuredCloneHelperInternal* helper =
static_cast<StructuredCloneHelperInternal*>(aClosure);
MOZ_ASSERT(helper);
return helper->ReadCallback(aCx, aReader, aTag, aIndex);
}
bool
StructuredCloneCallbacksWrite(JSContext* aCx,
JSStructuredCloneWriter* aWriter,
JS::Handle<JSObject*> aObj,
void* aClosure)
{
StructuredCloneHelperInternal* helper =
static_cast<StructuredCloneHelperInternal*>(aClosure);
MOZ_ASSERT(helper);
return helper->WriteCallback(aCx, aWriter, aObj);
}
bool
StructuredCloneCallbacksReadTransfer(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aTag,
void* aContent,
uint64_t aExtraData,
void* aClosure,
JS::MutableHandleObject aReturnObject)
{
StructuredCloneHelperInternal* helper =
static_cast<StructuredCloneHelperInternal*>(aClosure);
MOZ_ASSERT(helper);
return helper->ReadTransferCallback(aCx, aReader, aTag, aContent,
aExtraData, aReturnObject);
}
bool
StructuredCloneCallbacksWriteTransfer(JSContext* aCx,
JS::Handle<JSObject*> aObj,
void* aClosure,
// Output:
uint32_t* aTag,
JS::TransferableOwnership* aOwnership,
void** aContent,
uint64_t* aExtraData)
{
StructuredCloneHelperInternal* helper =
static_cast<StructuredCloneHelperInternal*>(aClosure);
MOZ_ASSERT(helper);
return helper->WriteTransferCallback(aCx, aObj, aTag, aOwnership, aContent,
aExtraData);
}
void
StructuredCloneCallbacksFreeTransfer(uint32_t aTag,
JS::TransferableOwnership aOwnership,
void* aContent,
uint64_t aExtraData,
void* aClosure)
{
StructuredCloneHelperInternal* helper =
static_cast<StructuredCloneHelperInternal*>(aClosure);
MOZ_ASSERT(helper);
return helper->FreeTransferCallback(aTag, aOwnership, aContent, aExtraData);
}
void
StructuredCloneCallbacksError(JSContext* aCx,
uint32_t aErrorId)
{
NS_WARNING("Failed to clone data.");
}
const JSStructuredCloneCallbacks gCallbacks = {
StructuredCloneCallbacksRead,
StructuredCloneCallbacksWrite,
StructuredCloneCallbacksError,
StructuredCloneCallbacksReadTransfer,
StructuredCloneCallbacksWriteTransfer,
StructuredCloneCallbacksFreeTransfer
};
} // anonymous namespace
// StructuredCloneHelperInternal class
StructuredCloneHelperInternal::StructuredCloneHelperInternal()
#ifdef DEBUG
: mShutdownCalled(false)
#endif
{}
StructuredCloneHelperInternal::~StructuredCloneHelperInternal()
{
#ifdef DEBUG
MOZ_ASSERT(mShutdownCalled);
#endif
}
void
StructuredCloneHelperInternal::Shutdown()
{
#ifdef DEBUG
mShutdownCalled = true;
#endif
mBuffer = nullptr;
}
bool
StructuredCloneHelperInternal::Write(JSContext* aCx,
JS::Handle<JS::Value> aValue)
{
return Write(aCx, aValue, JS::UndefinedHandleValue);
}
bool
StructuredCloneHelperInternal::Write(JSContext* aCx,
JS::Handle<JS::Value> aValue,
JS::Handle<JS::Value> aTransfer)
{
MOZ_ASSERT(!mBuffer, "Double Write is not allowed");
MOZ_ASSERT(!mShutdownCalled, "This method cannot be called after Shutdown.");
mBuffer = new JSAutoStructuredCloneBuffer(&gCallbacks, this);
if (!mBuffer->write(aCx, aValue, aTransfer, &gCallbacks, this)) {
mBuffer = nullptr;
return false;
}
return true;
}
bool
StructuredCloneHelperInternal::Read(JSContext* aCx,
JS::MutableHandle<JS::Value> aValue)
{
MOZ_ASSERT(mBuffer, "Read() without Write() is not allowed.");
MOZ_ASSERT(!mShutdownCalled, "This method cannot be called after Shutdown.");
bool ok = mBuffer->read(aCx, aValue, &gCallbacks, this);
return ok;
}
bool
StructuredCloneHelperInternal::ReadTransferCallback(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aTag,
void* aContent,
uint64_t aExtraData,
JS::MutableHandleObject aReturnObject)
{
MOZ_CRASH("Nothing to read.");
return false;
}
bool
StructuredCloneHelperInternal::WriteTransferCallback(JSContext* aCx,
JS::Handle<JSObject*> aObj,
uint32_t* aTag,
JS::TransferableOwnership* aOwnership,
void** aContent,
uint64_t* aExtraData)
{
// No transfers are supported by default.
return false;
}
void
StructuredCloneHelperInternal::FreeTransferCallback(uint32_t aTag,
JS::TransferableOwnership aOwnership,
void* aContent,
uint64_t aExtraData)
{
MOZ_CRASH("Nothing to free.");
}
// StructuredCloneHelper class
StructuredCloneHelper::StructuredCloneHelper(CloningSupport aSupportsCloning,
TransferringSupport aSupportsTransferring,
ContextSupport aContext)
: mSupportsCloning(aSupportsCloning == CloningSupported)
, mSupportsTransferring(aSupportsTransferring == TransferringSupported)
, mContext(aContext)
, mParent(nullptr)
#ifdef DEBUG
, mCreationThread(NS_GetCurrentThread())
#endif
{}
StructuredCloneHelper::~StructuredCloneHelper()
{
Shutdown();
MOZ_ASSERT(mTransferredPorts.IsEmpty());
}
void
StructuredCloneHelper::Write(JSContext* aCx,
JS::Handle<JS::Value> aValue,
ErrorResult& aRv)
{
Write(aCx, aValue, JS::UndefinedHandleValue, aRv);
}
void
StructuredCloneHelper::Write(JSContext* aCx,
JS::Handle<JS::Value> aValue,
JS::Handle<JS::Value> aTransfer,
ErrorResult& aRv)
{
MOZ_ASSERT_IF(mContext == SameProcessSameThread,
mCreationThread == NS_GetCurrentThread());
if (!StructuredCloneHelperInternal::Write(aCx, aValue, aTransfer)) {
aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
return;
}
if (mContext != SameProcessSameThread) {
for (uint32_t i = 0, len = mBlobImplArray.Length(); i < len; ++i) {
if (!mBlobImplArray[i]->MayBeClonedToOtherThreads()) {
aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
return;
}
}
}
}
void
StructuredCloneHelper::Read(nsISupports* aParent,
JSContext* aCx,
JS::MutableHandle<JS::Value> aValue,
ErrorResult& aRv)
{
MOZ_ASSERT_IF(mContext == SameProcessSameThread,
mCreationThread == NS_GetCurrentThread());
mozilla::AutoRestore<nsISupports*> guard(mParent);
mParent = aParent;
if (!StructuredCloneHelperInternal::Read(aCx, aValue)) {
JS_ClearPendingException(aCx);
aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
}
// If we are tranferring something, we cannot call 'Read()' more than once.
if (mSupportsTransferring) {
mBlobImplArray.Clear();
mClonedImages.Clear();
Shutdown();
}
}
void
StructuredCloneHelper::ReadFromBuffer(nsISupports* aParent,
JSContext* aCx,
uint64_t* aBuffer,
size_t aBufferLength,
JS::MutableHandle<JS::Value> aValue,
ErrorResult& aRv)
{
ReadFromBuffer(aParent, aCx, aBuffer, aBufferLength,
JS_STRUCTURED_CLONE_VERSION, aValue, aRv);
}
void
StructuredCloneHelper::ReadFromBuffer(nsISupports* aParent,
JSContext* aCx,
uint64_t* aBuffer,
size_t aBufferLength,
uint32_t aAlgorithmVersion,
JS::MutableHandle<JS::Value> aValue,
ErrorResult& aRv)
{
MOZ_ASSERT_IF(mContext == SameProcessSameThread,
mCreationThread == NS_GetCurrentThread());
MOZ_ASSERT(!mBuffer, "ReadFromBuffer() must be called without a Write().");
MOZ_ASSERT(aBuffer);
mozilla::AutoRestore<nsISupports*> guard(mParent);
mParent = aParent;
if (!JS_ReadStructuredClone(aCx, aBuffer, aBufferLength, aAlgorithmVersion,
aValue, &gCallbacks, this)) {
JS_ClearPendingException(aCx);
aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
}
}
void
StructuredCloneHelper::MoveBufferDataToArray(FallibleTArray<uint8_t>& aArray,
ErrorResult& aRv)
{
MOZ_ASSERT_IF(mContext == SameProcessSameThread,
mCreationThread == NS_GetCurrentThread());
MOZ_ASSERT(mBuffer, "MoveBuffer() cannot be called without a Write().");
if (NS_WARN_IF(!aArray.SetLength(BufferSize(), mozilla::fallible))) {
aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
return;
}
uint64_t* buffer;
size_t size;
mBuffer->steal(&buffer, &size);
mBuffer = nullptr;
memcpy(aArray.Elements(), buffer, size);
js_free(buffer);
}
void
StructuredCloneHelper::FreeBuffer(uint64_t* aBuffer,
size_t aBufferLength)
{
MOZ_ASSERT(!mBuffer, "FreeBuffer() must be called without a Write().");
MOZ_ASSERT(aBuffer);
MOZ_ASSERT(aBufferLength);
JS_ClearStructuredClone(aBuffer, aBufferLength, &gCallbacks, this, false);
}
namespace {
// Recursive!
already_AddRefed<BlobImpl>
EnsureBlobForBackgroundManager(BlobImpl* aBlobImpl,
PBackgroundChild* aManager = nullptr)
{
MOZ_ASSERT(aBlobImpl);
if (!aManager) {
aManager = BackgroundChild::GetForCurrentThread();
MOZ_ASSERT(aManager);
}
nsRefPtr<BlobImpl> blobImpl = aBlobImpl;
const nsTArray<nsRefPtr<BlobImpl>>* subBlobImpls =
aBlobImpl->GetSubBlobImpls();
if (!subBlobImpls || !subBlobImpls->Length()) {
if (nsCOMPtr<nsIRemoteBlob> remoteBlob = do_QueryObject(blobImpl)) {
// Always make sure we have a blob from an actor we can use on this
// thread.
BlobChild* blobChild = BlobChild::GetOrCreate(aManager, blobImpl);
MOZ_ASSERT(blobChild);
blobImpl = blobChild->GetBlobImpl();
MOZ_ASSERT(blobImpl);
DebugOnly<bool> isMutable;
MOZ_ASSERT(NS_SUCCEEDED(blobImpl->GetMutable(&isMutable)));
MOZ_ASSERT(!isMutable);
} else {
MOZ_ALWAYS_TRUE(NS_SUCCEEDED(blobImpl->SetMutable(false)));
}
return blobImpl.forget();
}
const uint32_t subBlobCount = subBlobImpls->Length();
MOZ_ASSERT(subBlobCount);
nsTArray<nsRefPtr<BlobImpl>> newSubBlobImpls;
newSubBlobImpls.SetLength(subBlobCount);
bool newBlobImplNeeded = false;
for (uint32_t index = 0; index < subBlobCount; index++) {
const nsRefPtr<BlobImpl>& subBlobImpl = subBlobImpls->ElementAt(index);
MOZ_ASSERT(subBlobImpl);
nsRefPtr<BlobImpl>& newSubBlobImpl = newSubBlobImpls[index];
newSubBlobImpl = EnsureBlobForBackgroundManager(subBlobImpl, aManager);
MOZ_ASSERT(newSubBlobImpl);
if (subBlobImpl != newSubBlobImpl) {
newBlobImplNeeded = true;
}
}
if (newBlobImplNeeded) {
nsString contentType;
blobImpl->GetType(contentType);
if (blobImpl->IsFile()) {
nsString name;
blobImpl->GetName(name);
blobImpl = new MultipartBlobImpl(newSubBlobImpls, name, contentType);
} else {
blobImpl = new MultipartBlobImpl(newSubBlobImpls, contentType);
}
MOZ_ALWAYS_TRUE(NS_SUCCEEDED(blobImpl->SetMutable(false)));
}
return blobImpl.forget();
}
JSObject*
ReadBlob(JSContext* aCx,
uint32_t aIndex,
StructuredCloneHelper* aHelper)
{
MOZ_ASSERT(aHelper);
MOZ_ASSERT(aIndex < aHelper->BlobImpls().Length());
nsRefPtr<BlobImpl> blobImpl = aHelper->BlobImpls()[aIndex];
blobImpl = EnsureBlobForBackgroundManager(blobImpl);
MOZ_ASSERT(blobImpl);
// nsRefPtr<File> needs to go out of scope before toObjectOrNull() is
// called because the static analysis thinks dereferencing XPCOM objects
// can GC (because in some cases it can!), and a return statement with a
// JSObject* type means that JSObject* is on the stack as a raw pointer
// while destructors are running.
JS::Rooted<JS::Value> val(aCx);
{
nsRefPtr<Blob> blob = Blob::Create(aHelper->ParentDuringRead(), blobImpl);
if (!ToJSValue(aCx, blob, &val)) {
return nullptr;
}
}
return &val.toObject();
}
bool
WriteBlob(JSStructuredCloneWriter* aWriter,
Blob* aBlob,
StructuredCloneHelper* aHelper)
{
MOZ_ASSERT(aWriter);
MOZ_ASSERT(aBlob);
MOZ_ASSERT(aHelper);
nsRefPtr<BlobImpl> blobImpl = EnsureBlobForBackgroundManager(aBlob->Impl());
MOZ_ASSERT(blobImpl);
// We store the position of the blobImpl in the array as index.
if (JS_WriteUint32Pair(aWriter, SCTAG_DOM_BLOB,
aHelper->BlobImpls().Length())) {
aHelper->BlobImpls().AppendElement(blobImpl);
return true;
}
return false;
}
// Read the WriteFileList for the format.
JSObject*
ReadFileList(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aCount,
StructuredCloneHelper* aHelper)
{
MOZ_ASSERT(aCx);
MOZ_ASSERT(aReader);
JS::Rooted<JS::Value> val(aCx);
{
nsRefPtr<FileList> fileList = new FileList(aHelper->ParentDuringRead());
uint32_t tag, offset;
// Offset is the index of the blobImpl from which we can find the blobImpl
// for this FileList.
if (!JS_ReadUint32Pair(aReader, &tag, &offset)) {
return nullptr;
}
MOZ_ASSERT(tag == 0);
// |aCount| is the number of BlobImpls to use from the |offset|.
for (uint32_t i = 0; i < aCount; ++i) {
uint32_t index = offset + i;
MOZ_ASSERT(index < aHelper->BlobImpls().Length());
nsRefPtr<BlobImpl> blobImpl = aHelper->BlobImpls()[index];
MOZ_ASSERT(blobImpl->IsFile());
blobImpl = EnsureBlobForBackgroundManager(blobImpl);
MOZ_ASSERT(blobImpl);
nsRefPtr<File> file = File::Create(aHelper->ParentDuringRead(), blobImpl);
if (!fileList->Append(file)) {
return nullptr;
}
}
if (!ToJSValue(aCx, fileList, &val)) {
return nullptr;
}
}
return &val.toObject();
}
// The format of the FileList serialization is:
// - pair of ints: SCTAG_DOM_FILELIST, Length of the FileList
// - pair of ints: 0, The offset of the BlobImpl array
bool
WriteFileList(JSStructuredCloneWriter* aWriter,
FileList* aFileList,
StructuredCloneHelper* aHelper)
{
MOZ_ASSERT(aWriter);
MOZ_ASSERT(aFileList);
MOZ_ASSERT(aHelper);
// A FileList is serialized writing the X number of elements and the offset
// from mBlobImplArray. The Read will take X elements from mBlobImplArray
// starting from the offset.
if (!JS_WriteUint32Pair(aWriter, SCTAG_DOM_FILELIST,
aFileList->Length()) ||
!JS_WriteUint32Pair(aWriter, 0,
aHelper->BlobImpls().Length())) {
return false;
}
for (uint32_t i = 0; i < aFileList->Length(); ++i) {
nsRefPtr<BlobImpl> blobImpl =
EnsureBlobForBackgroundManager(aFileList->Item(i)->Impl());
MOZ_ASSERT(blobImpl);
aHelper->BlobImpls().AppendElement(blobImpl);
}
return true;
}
// Read the WriteFormData for the format.
JSObject*
ReadFormData(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aCount,
StructuredCloneHelper* aHelper)
{
MOZ_ASSERT(aCx);
MOZ_ASSERT(aReader);
MOZ_ASSERT(aHelper);
// See the serialization of the FormData for the format.
JS::Rooted<JS::Value> val(aCx);
{
nsRefPtr<nsFormData> formData =
new nsFormData(aHelper->ParentDuringRead());
Optional<nsAString> thirdArg;
for (uint32_t i = 0; i < aCount; ++i) {
nsAutoString name;
if (!ReadString(aReader, name)) {
return nullptr;
}
uint32_t tag, indexOrLengthOfString;
if (!JS_ReadUint32Pair(aReader, &tag, &indexOrLengthOfString)) {
return nullptr;
}
if (tag == SCTAG_DOM_BLOB) {
MOZ_ASSERT(indexOrLengthOfString < aHelper->BlobImpls().Length());
nsRefPtr<BlobImpl> blobImpl =
aHelper->BlobImpls()[indexOrLengthOfString];
MOZ_ASSERT(blobImpl->IsFile());
nsRefPtr<File> file =
File::Create(aHelper->ParentDuringRead(), blobImpl);
MOZ_ASSERT(file);
formData->Append(name, *file, thirdArg);
} else {
MOZ_ASSERT(tag == 0);
nsAutoString value;
value.SetLength(indexOrLengthOfString);
size_t charSize = sizeof(nsString::char_type);
if (!JS_ReadBytes(aReader, (void*) value.BeginWriting(),
indexOrLengthOfString * charSize)) {
return nullptr;
}
formData->Append(name, value);
}
}
if (!ToJSValue(aCx, formData, &val)) {
return nullptr;
}
}
return &val.toObject();
}
// The format of the FormData serialization is:
// - pair of ints: SCTAG_DOM_FORMDATA, Length of the FormData elements
// - for each Element element:
// - name string
// - if it's a blob:
// - pair of ints: SCTAG_DOM_BLOB, index of the BlobImpl in the array
// mBlobImplArray.
// - else:
// - pair of ints: 0, string length
// - value string
bool
WriteFormData(JSStructuredCloneWriter* aWriter,
nsFormData* aFormData,
StructuredCloneHelper* aHelper)
{
MOZ_ASSERT(aWriter);
MOZ_ASSERT(aFormData);
MOZ_ASSERT(aHelper);
if (!JS_WriteUint32Pair(aWriter, SCTAG_DOM_FORMDATA,
aFormData->Length())) {
return false;
}
class MOZ_STACK_CLASS Closure final
{
JSStructuredCloneWriter* mWriter;
StructuredCloneHelper* mHelper;
public:
Closure(JSStructuredCloneWriter* aWriter,
StructuredCloneHelper* aHelper)
: mWriter(aWriter),
mHelper(aHelper)
{ }
static bool
Write(const nsString& aName, bool isFile, const nsString& aValue,
File* aFile, void* aClosure)
{
Closure* closure = static_cast<Closure*>(aClosure);
if (!WriteString(closure->mWriter, aName)) {
return false;
}
if (isFile) {
BlobImpl* blobImpl = aFile->Impl();
if (!JS_WriteUint32Pair(closure->mWriter, SCTAG_DOM_BLOB,
closure->mHelper->BlobImpls().Length())) {
return false;
}
closure->mHelper->BlobImpls().AppendElement(blobImpl);
return true;
}
size_t charSize = sizeof(nsString::char_type);
if (!JS_WriteUint32Pair(closure->mWriter, 0, aValue.Length()) ||
!JS_WriteBytes(closure->mWriter, aValue.get(),
aValue.Length() * charSize)) {
return false;
}
return true;
}
};
Closure closure(aWriter, aHelper);
return aFormData->ForEach(Closure::Write, &closure);
}
} // anonymous namespace
JSObject*
StructuredCloneHelper::ReadCallback(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aTag,
uint32_t aIndex)
{
MOZ_ASSERT(mSupportsCloning);
if (aTag == SCTAG_DOM_BLOB) {
return ReadBlob(aCx, aIndex, this);
}
if (aTag == SCTAG_DOM_FILELIST) {
return ReadFileList(aCx, aReader, aIndex, this);
}
if (aTag == SCTAG_DOM_IMAGEDATA) {
return ReadStructuredCloneImageData(aCx, aReader);
}
if (aTag == SCTAG_DOM_FORMDATA) {
return ReadFormData(aCx, aReader, aIndex, this);
}
if (aTag == SCTAG_DOM_IMAGEBITMAP) {
MOZ_ASSERT(mContext == SameProcessSameThread ||
mContext == SameProcessDifferentThread);
// Get the current global object.
// This can be null.
nsCOMPtr<nsIGlobalObject> parent = do_QueryInterface(mParent);
// aIndex is the index of the cloned image.
return ImageBitmap::ReadStructuredClone(aCx, aReader,
parent, GetImages(), aIndex);
}
return NS_DOMReadStructuredClone(aCx, aReader, aTag, aIndex, nullptr);
}
bool
StructuredCloneHelper::WriteCallback(JSContext* aCx,
JSStructuredCloneWriter* aWriter,
JS::Handle<JSObject*> aObj)
{
if (!mSupportsCloning) {
return false;
}
// See if this is a File/Blob object.
{
Blob* blob = nullptr;
if (NS_SUCCEEDED(UNWRAP_OBJECT(Blob, aObj, blob))) {
return WriteBlob(aWriter, blob, this);
}
}
// See if this is a FileList object.
{
FileList* fileList = nullptr;
if (NS_SUCCEEDED(UNWRAP_OBJECT(FileList, aObj, fileList))) {
return WriteFileList(aWriter, fileList, this);
}
}
// See if this is a ImageData object.
{
ImageData* imageData = nullptr;
if (NS_SUCCEEDED(UNWRAP_OBJECT(ImageData, aObj, imageData))) {
return WriteStructuredCloneImageData(aCx, aWriter, imageData);
}
}
// See if this is a FormData object.
{
nsFormData* formData = nullptr;
if (NS_SUCCEEDED(UNWRAP_OBJECT(FormData, aObj, formData))) {
return WriteFormData(aWriter, formData, this);
}
}
// See if this is an ImageBitmap object.
if (mContext == SameProcessSameThread ||
mContext == SameProcessDifferentThread) {
ImageBitmap* imageBitmap = nullptr;
if (NS_SUCCEEDED(UNWRAP_OBJECT(ImageBitmap, aObj, imageBitmap))) {
return ImageBitmap::WriteStructuredClone(aWriter,
GetImages(),
imageBitmap);
}
}
return NS_DOMWriteStructuredClone(aCx, aWriter, aObj, nullptr);
}
bool
StructuredCloneHelper::ReadTransferCallback(JSContext* aCx,
JSStructuredCloneReader* aReader,
uint32_t aTag,
void* aContent,
uint64_t aExtraData,
JS::MutableHandleObject aReturnObject)
{
MOZ_ASSERT(mSupportsTransferring);
if (aTag == SCTAG_DOM_MAP_MESSAGEPORT) {
// This can be null.
nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(mParent);
MOZ_ASSERT(aExtraData < mPortIdentifiers.Length());
const MessagePortIdentifier& portIdentifier = mPortIdentifiers[aExtraData];
// aExtraData is the index of this port identifier.
ErrorResult rv;
nsRefPtr<MessagePort> port =
MessagePort::Create(window, portIdentifier, rv);
if (NS_WARN_IF(rv.Failed())) {
return false;
}
mTransferredPorts.AppendElement(port);
JS::Rooted<JS::Value> value(aCx);
if (!GetOrCreateDOMReflector(aCx, port, &value)) {
JS_ClearPendingException(aCx);
return false;
}
aReturnObject.set(&value.toObject());
return true;
}
return false;
}
bool
StructuredCloneHelper::WriteTransferCallback(JSContext* aCx,
JS::Handle<JSObject*> aObj,
uint32_t* aTag,
JS::TransferableOwnership* aOwnership,
void** aContent,
uint64_t* aExtraData)
{
if (!mSupportsTransferring) {
return false;
}
{
MessagePortBase* port = nullptr;
nsresult rv = UNWRAP_OBJECT(MessagePort, aObj, port);
if (NS_SUCCEEDED(rv)) {
// We use aExtraData to store the index of this new port identifier.
*aExtraData = mPortIdentifiers.Length();
MessagePortIdentifier* identifier = mPortIdentifiers.AppendElement();
if (!port->CloneAndDisentangle(*identifier)) {
return false;
}
*aTag = SCTAG_DOM_MAP_MESSAGEPORT;
*aOwnership = JS::SCTAG_TMO_CUSTOM;
*aContent = nullptr;
return true;
}
}
return false;
}
void
StructuredCloneHelper::FreeTransferCallback(uint32_t aTag,
JS::TransferableOwnership aOwnership,
void* aContent,
uint64_t aExtraData)
{
MOZ_ASSERT(mSupportsTransferring);
if (aTag == SCTAG_DOM_MAP_MESSAGEPORT) {
MOZ_ASSERT(!aContent);
MOZ_ASSERT(aExtraData < mPortIdentifiers.Length());
MessagePort::ForceClose(mPortIdentifiers[aExtraData]);
}
}
} // dom namespace
} // mozilla namespace