firefox-main/dom/ipc/SharedMessageBody.cpp (file symbol)

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/* 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 "SharedMessageBody.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/MessagePort.h"
#include "mozilla/dom/PMessagePort.h"
#include "mozilla/dom/RefMessageBodyService.h"
#include "mozilla/ipc/BackgroundChild.h"
#include "mozilla/ipc/BackgroundParent.h"
#include "xpcpublic.h"
namespace mozilla {
using namespace ipc;
namespace dom {
SharedMessageBody::SharedMessageBody(
StructuredCloneHolder::TransferringSupport aSupportsTransferring,
const Maybe<nsID>& aAgentClusterId)
: mRefDataId(Nothing()),
mSupportsTransferring(aSupportsTransferring),
mAgentClusterId(aAgentClusterId) {}
SharedMessageBody::~SharedMessageBody() = default;
void SharedMessageBody::Write(JSContext* aCx, JS::Handle<JS::Value> aValue,
JS::Handle<JS::Value> aTransfers, nsID& aPortID,
RefMessageBodyService* aRefMessageBodyService,
ErrorResult& aRv) {
MOZ_ASSERT(!mCloneData && !mRefData);
MOZ_ASSERT(aRefMessageBodyService);
JS::CloneDataPolicy cloneDataPolicy;
// During a writing, we don't know the destination, so we assume it is part of
// the same agent cluster.
cloneDataPolicy.allowIntraClusterClonableSharedObjects();
nsIGlobalObject* global = xpc::CurrentNativeGlobal(aCx);
MOZ_ASSERT(global);
if (global->IsSharedMemoryAllowed()) {
cloneDataPolicy.allowSharedMemoryObjects();
}
mCloneData = MakeRefPtr<ipc::StructuredCloneData>(
JS::StructuredCloneScope::UnknownDestination, mSupportsTransferring);
mCloneData->Write(aCx, aValue, aTransfers, cloneDataPolicy, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return;
}
if (mCloneData->CloneScope() == JS::StructuredCloneScope::DifferentProcess) {
return;
}
MOZ_ASSERT(mCloneData->CloneScope() == JS::StructuredCloneScope::SameProcess);
RefPtr<RefMessageBody> refData = new RefMessageBody(aPortID, mCloneData);
mCloneData = nullptr;
mRefDataId.emplace(aRefMessageBodyService->Register(refData.forget(), aRv));
}
void SharedMessageBody::Read(JSContext* aCx,
JS::MutableHandle<JS::Value> aValue,
RefMessageBodyService* aRefMessageBodyService,
SharedMessageBody::ReadMethod aReadMethod,
ErrorResult& aRv) {
MOZ_ASSERT(aRefMessageBodyService);
if (mCloneData) {
// Use a default cloneDataPolicy here, because SharedArrayBuffers and WASM
// are not supported.
return mCloneData->Read(aCx, aValue, JS::CloneDataPolicy(), aRv);
}
JS::CloneDataPolicy cloneDataPolicy;
nsIGlobalObject* global = xpc::CurrentNativeGlobal(aCx);
MOZ_ASSERT(global);
// Clones within the same agent cluster are allowed to use shared array
// buffers and WASM modules.
if (mAgentClusterId.isSome()) {
Maybe<nsID> agentClusterId = global->GetAgentClusterId();
if (agentClusterId.isSome() &&
mAgentClusterId.value().Equals(agentClusterId.value())) {
cloneDataPolicy.allowIntraClusterClonableSharedObjects();
}
}
if (global->IsSharedMemoryAllowed()) {
cloneDataPolicy.allowSharedMemoryObjects();
}
MOZ_ASSERT(!mRefData);
MOZ_ASSERT(mRefDataId.isSome());
if (aReadMethod == SharedMessageBody::StealRefMessageBody) {
mRefData = aRefMessageBodyService->Steal(mRefDataId.value());
} else {
MOZ_ASSERT(aReadMethod == SharedMessageBody::KeepRefMessageBody);
mRefData = aRefMessageBodyService->GetAndCount(mRefDataId.value());
}
if (!mRefData) {
aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
return;
}
mRefData->Read(aCx, aValue, cloneDataPolicy, aRv);
}
bool SharedMessageBody::TakeTransferredPortsAsSequence(
Sequence<OwningNonNull<mozilla::dom::MessagePort>>& aPorts) {
if (mCloneData) {
return mCloneData->TakeTransferredPortsAsSequence(aPorts);
}
MOZ_ASSERT(mRefData);
return mRefData->TakeTransferredPortsAsSequence(aPorts);
}
} // namespace dom
} // namespace mozilla
namespace IPC {
void ParamTraits<mozilla::dom::SharedMessageBody*>::Write(
MessageWriter* aWriter, paramType* aParam) {
bool isNull = aParam == nullptr;
WriteParam(aWriter, isNull);
if (isNull) {
return;
}
bool supportsTransferring =
aParam->mSupportsTransferring ==
mozilla::dom::StructuredCloneHolder::TransferringSupported;
WriteParam(aWriter, supportsTransferring);
WriteParam(aWriter, aParam->mAgentClusterId);
WriteParam(aWriter, aParam->mCloneData);
if (!aParam->mCloneData) {
WriteParam(aWriter, aParam->mRefDataId);
}
}
bool ParamTraits<mozilla::dom::SharedMessageBody*>::Read(
MessageReader* aReader, RefPtr<paramType>* aResult) {
bool isNull;
if (!ReadParam(aReader, &isNull)) {
return false;
}
if (isNull) {
*aResult = nullptr;
return true;
}
bool supportsTransferring;
mozilla::Maybe<nsID> agentClusterId;
if (!ReadParam(aReader, &supportsTransferring) ||
!ReadParam(aReader, &agentClusterId)) {
return false;
}
RefPtr<paramType> result = new mozilla::dom::SharedMessageBody(
supportsTransferring
? mozilla::dom::StructuredCloneHolder::TransferringSupported
: mozilla::dom::StructuredCloneHolder::TransferringNotSupported,
agentClusterId);
if (!ReadParam(aReader, &result->mCloneData) ||
(!result->mCloneData && !ReadParam(aReader, &result->mRefDataId))) {
return false;
}
*aResult = result.forget();
return true;
}
} // namespace IPC