palemoon27/dom/ipc/StructuredCloneData.cpp

/* -*- 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 "StructuredCloneData.h"

#include "nsIDOMDOMException.h"
#include "nsIMutable.h"
#include "nsIXPConnect.h"

#include "mozilla/dom/BindingUtils.h"
#include "mozilla/dom/BlobBinding.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/ToJSValue.h"
#include "nsContentUtils.h"
#include "nsJSEnvironment.h"
#include "MainThreadUtils.h"
#include "StructuredCloneTags.h"
#include "jsapi.h"

namespace mozilla {
namespace dom {
namespace ipc {

bool
StructuredCloneData::Copy(const StructuredCloneData& aData)
{
  if (!aData.mData) {
    return true;
  }

  uint64_t* data = static_cast<uint64_t*>(js_malloc(aData.mDataLength));
  if (!data) {
    return false;
  }

  memcpy(data, aData.mData, aData.mDataLength);

  mData = data;
  mDataLength = aData.mDataLength;
  mDataOwned = eJSAllocated;

  MOZ_ASSERT(BlobImpls().IsEmpty());
  BlobImpls().AppendElements(aData.BlobImpls());

  MOZ_ASSERT(GetImages().IsEmpty());

  return true;
}

void
StructuredCloneData::Read(JSContext* aCx,
                          JS::MutableHandle<JS::Value> aValue,
                          ErrorResult &aRv)
{
  MOZ_ASSERT(mData);

  nsIGlobalObject *global = xpc::NativeGlobal(JS::CurrentGlobalOrNull(aCx));
  MOZ_ASSERT(global);

  ReadFromBuffer(global, aCx, mData, mDataLength, aValue, aRv);
}

void
StructuredCloneData::Write(JSContext* aCx,
                           JS::Handle<JS::Value> aValue,
                           ErrorResult &aRv)
{
  MOZ_ASSERT(!mData);

  StructuredCloneHelper::Write(aCx, aValue, aRv);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }

  mBuffer->steal(&mData, &mDataLength);
  mBuffer = nullptr;
  mDataOwned = eJSAllocated;
}

void
StructuredCloneData::WriteIPCParams(Message* aMsg) const
{
  WriteParam(aMsg, mDataLength);

  if (mDataLength) {
    // Structured clone data must be 64-bit aligned.
    aMsg->WriteBytes(mData, mDataLength, sizeof(uint64_t));
  }
}

bool
StructuredCloneData::ReadIPCParams(const IPC::Message* aMsg,
                                   void** aIter)
{
  MOZ_ASSERT(!mData);

  if (!ReadParam(aMsg, aIter, &mDataLength)) {
    return false;
  }

  if (!mDataLength) {
    return true;
  }

  const char** buffer =
    const_cast<const char**>(reinterpret_cast<char**>(&mData));
  // Structured clone data must be 64-bit aligned.
  if (!aMsg->ReadBytes(aIter, buffer, mDataLength, sizeof(uint64_t))) {
    return false;
  }

  uint64_t* data = static_cast<uint64_t*>(js_malloc(mDataLength));
  if (!data) {
     return false;
  }

  memcpy(data, mData, mDataLength);
  mData = data;
  mDataOwned = eJSAllocated;
  return true;
}

bool
StructuredCloneData::CopyExternalData(const void* aData,
                                      size_t aDataLength)
{
  MOZ_ASSERT(!mData);
  uint64_t* data = static_cast<uint64_t*>(js_malloc(aDataLength));
  if (!data) {
     return false;
  }

  memcpy(data, aData, aDataLength);
  mData = data;
  mDataLength = aDataLength;
  mDataOwned = eJSAllocated;

  return true;
}

} // namespace ipc
} // namespace dom
} // namespace mozilla