dom/presentation/ipc/PresentationBuilderChild.cpp
author Nicholas Nethercote <nnethercote@mozilla.com>
Fri, 02 Sep 2016 17:12:24 +1000
changeset 356450 177f41cecedb422d7a11156091ee718ec919c643
parent 355299 a8cc009739cd3885c2779042376397b0b2404870
child 358008 d2a4f2fc6716a1ba6e78c93342eac761f7524599
permissions -rw-r--r--
Bug 1299384 - Use MOZ_MUST_USE with NS_warn_if_impl(). r=erahm. This change avoids lots of false positives for Coverity's CHECKED_RETURN warning, caused by NS_WARN_IF's current use in both statement-style and expression-style. In the case where the code within the NS_WARN_IF has side-effects, I made the following change. > NS_WARN_IF(NS_FAILED(FunctionWithSideEffects())); > --> > Unused << NS_WARN_IF(NS_FAILED(FunctionWithSideEffects())); In the case where the code within the NS_WARN_IF lacks side-effects, I made the following change. > NS_WARN_IF(!condWithoutSideEffects); > --> > NS_WARNING_ASSERTION(condWithoutSideEffects, "msg"); This has two improvements. - The condition is not evaluated in non-debug builds. - The sense of the condition is inverted to the familiar "this condition should be true" sense used in assertions. A common variation on the side-effect-free case is the following. > nsresult rv = Fn(); > NS_WARN_IF_(NS_FAILED(rv)); > --> > DebugOnly<nsresult rv> = Fn(); > NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "Fn failed");

/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
/* vim: set ts=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 "DCPresentationChannelDescription.h"
#include "nsComponentManagerUtils.h"
#include "nsGlobalWindow.h"
#include "PresentationBuilderChild.h"
#include "PresentationIPCService.h"
#include "nsServiceManagerUtils.h"
#include "mozilla/Unused.h"

namespace mozilla {
namespace dom {

NS_IMPL_ISUPPORTS(PresentationBuilderChild,
                  nsIPresentationSessionTransportBuilderListener)

PresentationBuilderChild::PresentationBuilderChild(const nsString& aSessionId,
                                                   uint8_t aRole)
  : mSessionId(aSessionId)
  , mRole(aRole)
{
}

nsresult PresentationBuilderChild::Init()
{
  mBuilder = do_CreateInstance("@mozilla.org/presentation/datachanneltransportbuilder;1");
  if (NS_WARN_IF(!mBuilder)) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  uint64_t windowId = 0;

  nsCOMPtr<nsIPresentationService> service =
    do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  if (NS_WARN_IF(!service)) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  if (NS_WARN_IF(NS_FAILED(service->GetWindowIdBySessionId(
                           mSessionId,
                           mRole,
                           &windowId)))) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  nsPIDOMWindowInner* window = nsGlobalWindow::GetInnerWindowWithId(windowId)->AsInner();
  if (NS_WARN_IF(!window)) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  return mBuilder->BuildDataChannelTransport(mRole, window, this);
}

void
PresentationBuilderChild::ActorDestroy(ActorDestroyReason aWhy)
{
  mBuilder = nullptr;
  mActorDestroyed = true;
}

bool
PresentationBuilderChild::RecvOnOffer(const nsString& aSDP)
{
  if (NS_WARN_IF(!mBuilder)) {
    return false;
  }
  RefPtr<DCPresentationChannelDescription> description =
    new DCPresentationChannelDescription(aSDP);

  if (NS_WARN_IF(NS_FAILED(mBuilder->OnOffer(description)))) {
    return false;
  }
  return true;
}

bool
PresentationBuilderChild::RecvOnAnswer(const nsString& aSDP)
{
  if (NS_WARN_IF(!mBuilder)) {
    return false;
  }
  RefPtr<DCPresentationChannelDescription> description =
    new DCPresentationChannelDescription(aSDP);

  if (NS_WARN_IF(NS_FAILED(mBuilder->OnAnswer(description)))) {
    return false;
  }
  return true;
}

bool
PresentationBuilderChild::RecvOnIceCandidate(const nsString& aCandidate)
{
  if (NS_WARN_IF(NS_FAILED(mBuilder->OnIceCandidate(aCandidate)))) {
    return false;
  }
  return true;
}

// nsPresentationSessionTransportBuilderListener
NS_IMETHODIMP
PresentationBuilderChild::OnSessionTransport(nsIPresentationSessionTransport* aTransport)
{
  if (NS_WARN_IF(mActorDestroyed || !SendOnSessionTransport())){
    return NS_ERROR_FAILURE;
  }

  nsCOMPtr<nsIPresentationService> service =
    do_GetService(PRESENTATION_SERVICE_CONTRACTID);
  NS_WARNING_ASSERTION(service, "no presentation service");
  if (service) {
    Unused << NS_WARN_IF(NS_FAILED(static_cast<PresentationIPCService*>(service.get())->
                                     NotifySessionTransport(mSessionId, mRole, aTransport)));
  }
  mBuilder = nullptr;
  return NS_OK;
}

NS_IMETHODIMP
PresentationBuilderChild::OnError(nsresult reason)
{
  mBuilder = nullptr;

  if (NS_WARN_IF(mActorDestroyed || !SendOnSessionTransportError(reason))){
    return NS_ERROR_FAILURE;
  }
  return NS_OK;
}

NS_IMETHODIMP
PresentationBuilderChild::SendOffer(nsIPresentationChannelDescription* aOffer)
{
  nsAutoString SDP;
  nsresult rv = aOffer->GetDataChannelSDP(SDP);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  if (NS_WARN_IF(mActorDestroyed || !SendSendOffer(SDP))){
    return NS_ERROR_FAILURE;
  }
  return NS_OK;
}

NS_IMETHODIMP
PresentationBuilderChild::SendAnswer(nsIPresentationChannelDescription* aAnswer)
{
  nsAutoString SDP;
  nsresult rv = aAnswer->GetDataChannelSDP(SDP);
  if (NS_WARN_IF(NS_FAILED(rv))) {
    return rv;
  }

  if (NS_WARN_IF(mActorDestroyed || !SendSendAnswer(SDP))){
    return NS_ERROR_FAILURE;
  }
  return NS_OK;
}

NS_IMETHODIMP
PresentationBuilderChild::SendIceCandidate(const nsAString& candidate)
{
  if (NS_WARN_IF(mActorDestroyed || !SendSendIceCandidate(nsString(candidate)))) {
    return NS_ERROR_FAILURE;
  }
  return NS_OK;
}

NS_IMETHODIMP
PresentationBuilderChild::Close(nsresult reason)
{
  if (NS_WARN_IF(mActorDestroyed || !SendClose(reason))) {
    return NS_ERROR_FAILURE;
  }
  return NS_OK;
}

} // namespace dom
} // namespace mozilla