dom/media/AutoplayPolicy.h
author Mike Hommey <mh+mozilla@glandium.org>
Fri, 11 Jan 2019 16:01:15 +0000
changeset 453570 daf50f25895db073e44d50fecf2e4f6fe873865d
parent 452962 54b628e16c5c87cecadbc246838e72fb1c9b4d54
child 453890 63c3828351f0ad793bd8e58426ea5dcc1990aa76
permissions -rw-r--r--
Bug 1519307 - Add a new project to build useful parts of breakpad independently. r=froydnj With `ac_add_options --enable-project=tools/crashreporter` in a mozconfig, `./mach build` builds minidump_stackwalk, dump_syms and fileid. One caveat is that due to limitation in how the build system works currently, it's cumbersome to keep dump_syms as a host program for Gecko, and to make it a target program for this project. For now, keep it as a host program. We're not going to use it on automation, but it's still convenient to have for quick local builds (I've had to resort to awful hacks downstream). Differential Revision: https://phabricator.services.mozilla.com/D16299

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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/. */

#if !defined(AutoplayPolicy_h_)
#define AutoplayPolicy_h_

#include "mozilla/NotNull.h"

namespace mozilla {
namespace dom {

class HTMLMediaElement;
class AudioContext;
class Document;

/**
 * AutoplayPolicy is used to manage autoplay logic for all kinds of media,
 * including MediaElement, Web Audio and Web Speech.
 *
 * Autoplay could be disable by setting the pref "media.autoplay.default"
 * to anything but nsIAutoplay::Allowed. Once user disables autoplay, media
 * could only be played if one of following conditions is true.
 * 1) Owner document is activated by user gestures
 *    We restrict user gestures to "mouse click", "keyboard press" and "touch".
 * 2) Muted media content or video without audio content.
 * 3) Document's origin has the "autoplay-media" permission.
 */
class AutoplayPolicy {
 public:
  // Returns whether a given media element is allowed to play.
  static bool IsAllowedToPlay(const HTMLMediaElement& aElement);

  // Returns whether a given AudioContext is allowed to play.
  static bool IsAllowedToPlay(const AudioContext& aContext);

  // Returns true if a given media element would be allowed to play
  // if block autoplay was enabled. If this returns false, it means we would
  // either block or ask for permission.
  // Note: this is for telemetry purposes, and doesn't check the prefs
  // which enable/disable block autoplay. Do not use for blocking logic!
  static bool WouldBeAllowedToPlayIfAutoplayDisabled(
      const HTMLMediaElement& aElement);

  // Returns true if a given AudioContext would be allowed to play
  // if block autoplay was enabled. If this returns false, it means we would
  // either block or ask for permission.
  // Note: this is for telemetry purposes, and doesn't check the prefs
  // which enable/disable block autoplay. Do not use for blocking logic!
  static bool WouldBeAllowedToPlayIfAutoplayDisabled(
      const AudioContext& aContext);
};

}  // namespace dom
}  // namespace mozilla

#endif