gecko/ipc/glue/InputStreamUtils.cpp

/* 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 "InputStreamUtils.h"

#include "nsIIPCSerializableInputStream.h"

#include "mozilla/Assertions.h"
#include "nsComponentManagerUtils.h"
#include "nsDebug.h"
#include "nsID.h"
#include "nsMultiplexInputStream.h"
#include "nsNetCID.h"
#include "nsStringStream.h"
#include "nsThreadUtils.h"

using namespace mozilla::ipc;

namespace {

NS_DEFINE_CID(kStringInputStreamCID, NS_STRINGINPUTSTREAM_CID);
NS_DEFINE_CID(kFileInputStreamCID, NS_LOCALFILEINPUTSTREAM_CID);
NS_DEFINE_CID(kPartialFileInputStreamCID, NS_PARTIALLOCALFILEINPUTSTREAM_CID);
NS_DEFINE_CID(kMultiplexInputStreamCID, NS_MULTIPLEXINPUTSTREAM_CID);

} // anonymous namespace

namespace mozilla {
namespace ipc {

already_AddRefed<nsIInputStream>
DeserializeInputStream(const InputStreamParams& aParams)
{
  MOZ_ASSERT(NS_IsMainThread());

  nsCOMPtr<nsIIPCSerializableInputStream> serializable;

  switch (aParams.type()) {
    case InputStreamParams::T__None:
      NS_WARNING("This union has no type!");
      return nullptr;

    case InputStreamParams::TStringInputStreamParams:
      serializable = do_CreateInstance(kStringInputStreamCID);
      break;

    case InputStreamParams::TFileInputStreamParams:
      serializable = do_CreateInstance(kFileInputStreamCID);
      break;

    case InputStreamParams::TPartialFileInputStreamParams:
      serializable = do_CreateInstance(kPartialFileInputStreamCID);
      break;

    case InputStreamParams::TMultiplexInputStreamParams:
      serializable = do_CreateInstance(kMultiplexInputStreamCID);
      break;

    default:
      NS_WARNING("Unknown params!");
      return nullptr;
  }

  MOZ_ASSERT(serializable);

  if (!serializable->Deserialize(aParams)) {
    NS_WARNING("Deserialize failed!");
    return nullptr;
  }

  nsCOMPtr<nsIInputStream> stream = do_QueryInterface(serializable);
  MOZ_ASSERT(stream);

  return stream.forget();
}

} // namespace ipc
} // namespace mozilla