DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (4a108e94d3e2)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285
/* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 "WakeLock.h"
#include "mozilla/dom/ContentParent.h"
#include "mozilla/dom/Event.h" // for nsIDOMEvent::InternalDOMEvent()
#include "mozilla/dom/MozWakeLockBinding.h"
#include "mozilla/Hal.h"
#include "mozilla/HalWakeLock.h"
#include "nsError.h"
#include "nsIDocument.h"
#include "nsIDOMWindow.h"
#include "nsIDOMEvent.h"
#include "nsPIDOMWindow.h"
#include "nsIPropertyBag2.h"

using namespace mozilla::hal;

namespace mozilla {
namespace dom {

NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_0(WakeLock)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WakeLock)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMEventListener)
  NS_INTERFACE_MAP_ENTRY(nsIDOMEventListener)
  NS_INTERFACE_MAP_ENTRY(nsIObserver)
  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(WakeLock)
NS_IMPL_CYCLE_COLLECTING_RELEASE(WakeLock)

WakeLock::WakeLock()
  : mLocked(false)
  , mHidden(true)
  , mContentParentID(CONTENT_PROCESS_ID_UNKNOWN)
{
}

WakeLock::~WakeLock()
{
  DoUnlock();
  DetachEventListener();
}

JSObject*
WakeLock::WrapObject(JSContext* aCx)
{
  return MozWakeLockBinding::Wrap(aCx, this);
}

nsresult
WakeLock::Init(const nsAString &aTopic, nsIDOMWindow *aWindow)
{
  // Don't Init() a WakeLock twice.
  MOZ_ASSERT(mTopic.IsEmpty());

  if (aTopic.IsEmpty()) {
    return NS_ERROR_INVALID_ARG;
  }

  mTopic.Assign(aTopic);

  mWindow = do_GetWeakReference(aWindow);
  nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aWindow);

  /**
   * Null windows are allowed. A wake lock without associated window
   * is always considered invisible.
   */
  if (window) {
    nsCOMPtr<nsIDocument> doc = window->GetExtantDoc();
    NS_ENSURE_STATE(doc);
    mHidden = doc->Hidden();
  }

  AttachEventListener();
  DoLock();

  return NS_OK;
}

nsresult
WakeLock::Init(const nsAString& aTopic, ContentParent* aContentParent)
{
  // Don't Init() a WakeLock twice.
  MOZ_ASSERT(mTopic.IsEmpty());
  MOZ_ASSERT(aContentParent);

  if (aTopic.IsEmpty()) {
    return NS_ERROR_INVALID_ARG;
  }

  mTopic.Assign(aTopic);
  mContentParentID = aContentParent->ChildID();
  mHidden = false;

  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
  if (obs) {
    obs->AddObserver(this, "ipc:content-shutdown", /* ownsWeak */ true);
  }

  DoLock();
  return NS_OK;
}

NS_IMETHODIMP
WakeLock::Observe(nsISupports* aSubject, const char* aTopic, const char16_t* data)
{
  // If this wake lock was acquired on behalf of another process, unlock it
  // when that process dies.
  //
  // Note that we do /not/ call DoUnlock() here!  The wake lock back-end is
  // already listening for ipc:content-shutdown messages and will clear out its
  // tally for the process when it dies.  All we need to do here is ensure that
  // unlock() becomes a nop.

  MOZ_ASSERT(!strcmp(aTopic, "ipc:content-shutdown"));

  nsCOMPtr<nsIPropertyBag2> props = do_QueryInterface(aSubject);
  if (!props) {
    NS_WARNING("ipc:content-shutdown message without property bag as subject");
    return NS_OK;
  }

  uint64_t childID = 0;
  nsresult rv = props->GetPropertyAsUint64(NS_LITERAL_STRING("childID"),
                                           &childID);
  if (NS_SUCCEEDED(rv)) {
    if (childID == mContentParentID) {
      mLocked = false;
    }
  } else {
    NS_WARNING("ipc:content-shutdown message without childID property");
  }
  return NS_OK;
}

void
WakeLock::DoLock()
{
  if (!mLocked) {
    // Change the flag immediately to prevent recursive reentering
    mLocked = true;

    hal::ModifyWakeLock(mTopic,
                        hal::WAKE_LOCK_ADD_ONE,
                        mHidden ? hal::WAKE_LOCK_ADD_ONE : hal::WAKE_LOCK_NO_CHANGE,
                        mContentParentID);
  }
}

void
WakeLock::DoUnlock()
{
  if (mLocked) {
    // Change the flag immediately to prevent recursive reentering
    mLocked = false;

    hal::ModifyWakeLock(mTopic,
                        hal::WAKE_LOCK_REMOVE_ONE,
                        mHidden ? hal::WAKE_LOCK_REMOVE_ONE : hal::WAKE_LOCK_NO_CHANGE,
                        mContentParentID);
  }
}

void
WakeLock::AttachEventListener()
{
  nsCOMPtr<nsPIDOMWindow> window = do_QueryReferent(mWindow);

  if (window) {
    nsCOMPtr<nsIDocument> doc = window->GetExtantDoc();
    if (doc) {
      doc->AddSystemEventListener(NS_LITERAL_STRING("visibilitychange"),
                                  this,
                                  /* useCapture = */ true,
                                  /* wantsUntrusted = */ false);

      nsCOMPtr<EventTarget> target = do_QueryInterface(window);
      target->AddSystemEventListener(NS_LITERAL_STRING("pagehide"),
                                     this,
                                     /* useCapture = */ true,
                                     /* wantsUntrusted = */ false);
      target->AddSystemEventListener(NS_LITERAL_STRING("pageshow"),
                                     this,
                                     /* useCapture = */ true,
                                     /* wantsUntrusted = */ false);
    }
  }
}

void
WakeLock::DetachEventListener()
{
  nsCOMPtr<nsPIDOMWindow> window = do_QueryReferent(mWindow);

  if (window) {
    nsCOMPtr<nsIDocument> doc = window->GetExtantDoc();
    if (doc) {
      doc->RemoveSystemEventListener(NS_LITERAL_STRING("visibilitychange"),
                                     this,
                                     /* useCapture = */ true);
      nsCOMPtr<EventTarget> target = do_QueryInterface(window);
      target->RemoveSystemEventListener(NS_LITERAL_STRING("pagehide"),
                                        this,
                                        /* useCapture = */ true);
      target->RemoveSystemEventListener(NS_LITERAL_STRING("pageshow"),
                                        this,
                                        /* useCapture = */ true);
    }
  }
}

void
WakeLock::Unlock(ErrorResult& aRv)
{
  /*
   * We throw NS_ERROR_DOM_INVALID_STATE_ERR on double unlock.
   */
  if (!mLocked) {
    aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  DoUnlock();
  DetachEventListener();
}

void
WakeLock::GetTopic(nsAString &aTopic)
{
  aTopic.Assign(mTopic);
}

NS_IMETHODIMP
WakeLock::HandleEvent(nsIDOMEvent *aEvent)
{
  nsAutoString type;
  aEvent->GetType(type);

  if (type.EqualsLiteral("visibilitychange")) {
    nsCOMPtr<nsIDocument> doc =
      do_QueryInterface(aEvent->InternalDOMEvent()->GetTarget());
    NS_ENSURE_STATE(doc);

    bool oldHidden = mHidden;
    mHidden = doc->Hidden();

    if (mLocked && oldHidden != mHidden) {
      hal::ModifyWakeLock(mTopic,
                          hal::WAKE_LOCK_NO_CHANGE,
                          mHidden ? hal::WAKE_LOCK_ADD_ONE : hal::WAKE_LOCK_REMOVE_ONE,
                          mContentParentID);
    }

    return NS_OK;
  }

  if (type.EqualsLiteral("pagehide")) {
    DoUnlock();
    return NS_OK;
  }

  if (type.EqualsLiteral("pageshow")) {
    DoLock();
    return NS_OK;
  }

  return NS_OK;
}

nsISupports*
WakeLock::GetParentObject() const
{
  nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(mWindow);
  return window;
}

} // dom
} // mozilla