hal/Hal.h
author Jim Blandy <jimb@mozilla.com>
Tue, 12 Feb 2019 08:16:16 +0000
changeset 458932 414b2c238839c321dee78a9d927c968f1e52ae79
parent 454520 5f4630838d46dd81dadb13220a4af0da9e23a619
permissions -rw-r--r--
Bug 1145201: Replace EnqueuePromiseJobCallback and GetIncumbentGlobalCallback with new JobQueue abstract base class. r=arai,smaug While the behavior of ECMAScript Promises and their associated job queue is covered by the ECMAScript standard, the HTML specification amends that with additional behavior the web platform requires. To support this, SpiderMonkey provides hooks the embedding can set to replace SpiderMonkey's queue with its own implementation. At present, these hooks are C-style function-pointer-and-void-pointer pairs, which are awkward to handle and mistake-prone, as passing a function the wrong void* is not a type error. Later patches in this series must add new hooks, making a bad situation worse. A C++ abstract base class is a well-typed alternative. This introduces a new `JS::JobQueue` abstract class, and adapts SpiderMonkey's internal job queue and Gecko's customization to use it. `GetIncumbentGlobalCallback` and `EnqueuePromiseJobCallback` become virtual methods. Within SpiderMonkey, the patch gathers the various fields of JSContext that implement the internal queue into their own type, js::InternalJobQueue. Various jsfriendapi functions become veneers for calls to methods specific to the derived class. The InternalJobQueue type itself remains private to SpiderMonkey, as it uses types like TraceableFifo, derived from Fifo, that are not part of SpiderMonkey's public API. Within Gecko, CycleCollectedJSContext acquires JS::JobQueue as a private base class, and a few static methods are cleaned up nicely. There are a few other hooks defined in js/public/Promise.h that might make sense to turn into virtual methods on JobQueue. For example, DispatchToEventLoopCallback, used for resolving promises of results from off-main-thread tasks, is probably necessarily connected to the JobQueue implementation in use, so it might not be sensible to set one without the other. But it was left unchanged to reduce this patch's size. Differential Revision: https://phabricator.services.mozilla.com/D17544

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et ft=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/. */

#ifndef mozilla_Hal_h
#define mozilla_Hal_h

#include "base/basictypes.h"
#include "base/platform_thread.h"
#include "nsTArray.h"
#include "mozilla/hal_sandbox/PHal.h"
#include "mozilla/HalBatteryInformation.h"
#include "mozilla/HalNetworkInformation.h"
#include "mozilla/HalScreenConfiguration.h"
#include "mozilla/HalWakeLockInformation.h"
#include "mozilla/HalTypes.h"
#include "mozilla/Types.h"

/*
 * Hal.h contains the public Hal API.
 *
 * By default, this file defines its functions in the hal namespace, but if
 * MOZ_HAL_NAMESPACE is defined, we'll define our functions in that namespace.
 *
 * This is used by HalImpl.h and HalSandbox.h, which define copies of all the
 * functions here in the hal_impl and hal_sandbox namespaces.
 */

class nsPIDOMWindowInner;

#ifndef MOZ_HAL_NAMESPACE
#  define MOZ_HAL_NAMESPACE hal
#  define MOZ_DEFINED_HAL_NAMESPACE 1
#endif

namespace mozilla {

namespace hal {

class WindowIdentifier;

}  // namespace hal

namespace MOZ_HAL_NAMESPACE {

/**
 * Initializes the HAL. This must be called before any other HAL function.
 */
void Init();

/**
 * Shuts down the HAL. Besides freeing all the used resources this will check
 * that all observers have been properly deregistered and assert if not.
 */
void Shutdown();

/**
 * Turn the default vibrator device on/off per the pattern specified
 * by |pattern|.  Each element in the pattern is the number of
 * milliseconds to turn the vibrator on or off.  The first element in
 * |pattern| is an "on" element, the next is "off", and so on.
 *
 * If |pattern| is empty, any in-progress vibration is canceled.
 *
 * Only an active window within an active tab may call Vibrate; calls
 * from inactive windows and windows on inactive tabs do nothing.
 *
 * If you're calling hal::Vibrate from the outside world, pass an
 * nsIDOMWindow* in place of the WindowIdentifier parameter.
 * The method with WindowIdentifier will be called automatically.
 */
void Vibrate(const nsTArray<uint32_t>& pattern, nsPIDOMWindowInner* aWindow);
void Vibrate(const nsTArray<uint32_t>& pattern,
             const hal::WindowIdentifier& id);

/**
 * Cancel a vibration started by the content window identified by
 * WindowIdentifier.
 *
 * If the window was the last window to start a vibration, the
 * cancellation request will go through even if the window is not
 * active.
 *
 * As with hal::Vibrate(), if you're calling hal::CancelVibrate from the outside
 * world, pass an nsIDOMWindow*. The method with WindowIdentifier will be called
 * automatically.
 */
void CancelVibrate(nsPIDOMWindowInner* aWindow);
void CancelVibrate(const hal::WindowIdentifier& id);

#define MOZ_DEFINE_HAL_OBSERVER(name_)                             \
  /**                                                              \
   * Inform the backend there is a new |name_| observer.           \
   * @param aObserver The observer that should be added.           \
   */                                                              \
  void Register##name_##Observer(hal::name_##Observer* aObserver); \
  /**                                                              \
   * Inform the backend a |name_| observer unregistered.           \
   * @param aObserver The observer that should be removed.         \
   */                                                              \
  void Unregister##name_##Observer(hal::name_##Observer* aObserver);

MOZ_DEFINE_HAL_OBSERVER(Battery);

/**
 * Returns the current battery information.
 */
void GetCurrentBatteryInformation(hal::BatteryInformation* aBatteryInfo);

/**
 * Notify of a change in the battery state.
 * @param aBatteryInfo The new battery information.
 */
void NotifyBatteryChange(const hal::BatteryInformation& aBatteryInfo);

/**
 * Register an observer for the sensor of given type.
 *
 * The observer will receive data whenever the data generated by the
 * sensor is avaiable.
 */
void RegisterSensorObserver(hal::SensorType aSensor,
                            hal::ISensorObserver* aObserver);

/**
 * Unregister an observer for the sensor of given type.
 */
void UnregisterSensorObserver(hal::SensorType aSensor,
                              hal::ISensorObserver* aObserver);

/**
 * Post a value generated by a sensor.
 *
 * This API is internal to hal; clients shouldn't call it directly.
 */
void NotifySensorChange(const hal::SensorData& aSensorData);

/**
 * Enable sensor notifications from the backend
 *
 * This method is only visible from implementation of sensor manager.
 * Rest of the system should not try this.
 */
void EnableSensorNotifications(hal::SensorType aSensor);

/**
 * Disable sensor notifications from the backend
 *
 * This method is only visible from implementation of sensor manager.
 * Rest of the system should not try this.
 */
void DisableSensorNotifications(hal::SensorType aSensor);

MOZ_DEFINE_HAL_OBSERVER(Network);

/**
 * Returns the current network information.
 */
void GetCurrentNetworkInformation(hal::NetworkInformation* aNetworkInfo);

/**
 * Notify of a change in the network state.
 * @param aNetworkInfo The new network information.
 */
void NotifyNetworkChange(const hal::NetworkInformation& aNetworkInfo);

/**
 * Enable wake lock notifications from the backend.
 *
 * This method is only used by WakeLockObserversManager.
 */
void EnableWakeLockNotifications();

/**
 * Disable wake lock notifications from the backend.
 *
 * This method is only used by WakeLockObserversManager.
 */
void DisableWakeLockNotifications();

MOZ_DEFINE_HAL_OBSERVER(WakeLock);

/**
 * Adjust a wake lock's counts on behalf of a given process.
 *
 * In most cases, you shouldn't need to pass the aProcessID argument; the
 * default of CONTENT_PROCESS_ID_UNKNOWN is probably what you want.
 *
 * @param aTopic        lock topic
 * @param aLockAdjust   to increase or decrease active locks
 * @param aHiddenAdjust to increase or decrease hidden locks
 * @param aProcessID    indicates which process we're modifying the wake lock
 *                      on behalf of.  It is interpreted as
 *
 *                      CONTENT_PROCESS_ID_UNKNOWN: The current process
 *                      CONTENT_PROCESS_ID_MAIN: The root process
 *                      X: The process with ContentChild::GetID() == X
 */
void ModifyWakeLock(const nsAString& aTopic, hal::WakeLockControl aLockAdjust,
                    hal::WakeLockControl aHiddenAdjust,
                    uint64_t aProcessID = hal::CONTENT_PROCESS_ID_UNKNOWN);

/**
 * Query the wake lock numbers of aTopic.
 * @param aTopic        lock topic
 * @param aWakeLockInfo wake lock numbers
 */
void GetWakeLockInfo(const nsAString& aTopic,
                     hal::WakeLockInformation* aWakeLockInfo);

/**
 * Notify of a change in the wake lock state.
 * @param aWakeLockInfo The new wake lock information.
 */
void NotifyWakeLockChange(const hal::WakeLockInformation& aWakeLockInfo);

MOZ_DEFINE_HAL_OBSERVER(ScreenConfiguration);

/**
 * Returns the current screen configuration.
 */
void GetCurrentScreenConfiguration(
    hal::ScreenConfiguration* aScreenConfiguration);

/**
 * Notify of a change in the screen configuration.
 * @param aScreenConfiguration The new screen orientation.
 */
void NotifyScreenConfigurationChange(
    const hal::ScreenConfiguration& aScreenConfiguration);

/**
 * Lock the screen orientation to the specific orientation.
 * @return Whether the lock has been accepted.
 */
MOZ_MUST_USE bool LockScreenOrientation(
    const hal::ScreenOrientation& aOrientation);

/**
 * Unlock the screen orientation.
 */
void UnlockScreenOrientation();

/**
 * Return true if the current platform supports the setting of process
 * priority.
 */
bool SetProcessPrioritySupported();

/**
 * Set the priority of the given process.
 *
 * Exactly what this does will vary between platforms.  On *nix we might give
 * background processes higher nice values.  On other platforms, we might
 * ignore this call entirely.
 */
void SetProcessPriority(int aPid, hal::ProcessPriority aPriority);

}  // namespace MOZ_HAL_NAMESPACE
}  // namespace mozilla

#ifdef MOZ_DEFINED_HAL_NAMESPACE
#  undef MOZ_DEFINED_HAL_NAMESPACE
#  undef MOZ_HAL_NAMESPACE
#endif

#endif  // mozilla_Hal_h