dom/base/nsScreen.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "nsContentUtils.h"
   8 #include "nsScreen.h"
   9 #include "mozilla/dom/Document.h"
  10 #include "nsGlobalWindowInner.h"
  11 #include "nsGlobalWindowOuter.h"
  12 #include "nsIDocShell.h"
  13 #include "nsPresContext.h"
  14 #include "nsCOMPtr.h"
  15 #include "nsIDocShellTreeItem.h"
  16 #include "nsLayoutUtils.h"
  17 #include "nsDeviceContext.h"
  18 #include "mozilla/widget/ScreenManager.h"
  19
  20 using namespace mozilla;
  21 using namespace mozilla::dom;
  22
  23 nsScreen::nsScreen(nsPIDOMWindowInner* aWindow)
  24     : DOMEventTargetHelper(aWindow),
  25       mScreenOrientation(new ScreenOrientation(aWindow, this)) {}
  26
  27 nsScreen::~nsScreen() = default;
  28
  29 // QueryInterface implementation for nsScreen
  30 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsScreen)
  31 NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
  32
  33 NS_IMPL_ADDREF_INHERITED(nsScreen, DOMEventTargetHelper)
  34 NS_IMPL_RELEASE_INHERITED(nsScreen, DOMEventTargetHelper)
  35
  36 NS_IMPL_CYCLE_COLLECTION_INHERITED(nsScreen, DOMEventTargetHelper,
  37                                    mScreenOrientation)
  38
  39 int32_t nsScreen::PixelDepth() {
  40   // Return 24 to prevent fingerprinting.
  41   if (ShouldResistFingerprinting(RFPTarget::ScreenPixelDepth)) {
  42     return 24;
  43   }
  44   nsDeviceContext* context = GetDeviceContext();
  45   if (NS_WARN_IF(!context)) {
  46     return 24;
  47   }
  48   return context->GetDepth();
  49 }
  50
  51 nsPIDOMWindowOuter* nsScreen::GetOuter() const {
  52   if (nsPIDOMWindowInner* inner = GetOwnerWindow()) {
  53     return inner->GetOuterWindow();
  54   }
  55   return nullptr;
  56 }
  57
  58 nsDeviceContext* nsScreen::GetDeviceContext() const {
  59   return nsLayoutUtils::GetDeviceContextForScreenInfo(GetOuter());
  60 }
  61
  62 CSSIntRect nsScreen::GetRect() {
  63   // Return window inner rect to prevent fingerprinting.
  64   if (ShouldResistFingerprinting(RFPTarget::ScreenRect)) {
  65     return GetTopWindowInnerRectForRFP();
  66   }
  67
  68   // Here we manipulate the value of aRect to represent the screen size,
  69   // if in RDM.
  70   if (nsPIDOMWindowInner* owner = GetOwnerWindow()) {
  71     if (Document* doc = owner->GetExtantDoc()) {
  72       Maybe<CSSIntSize> deviceSize =
  73           nsGlobalWindowOuter::GetRDMDeviceSize(*doc);
  74       if (deviceSize.isSome()) {
  75         const CSSIntSize& size = deviceSize.value();
  76         return {0, 0, size.width, size.height};
  77       }
  78     }
  79   }
  80
  81   nsDeviceContext* context = GetDeviceContext();
  82   if (NS_WARN_IF(!context)) {
  83     return {};
  84   }
  85   return CSSIntRect::FromAppUnitsRounded(context->GetRect());
  86 }
  87
  88 CSSIntRect nsScreen::GetAvailRect() {
  89   // Return window inner rect to prevent fingerprinting.
  90   if (ShouldResistFingerprinting(RFPTarget::ScreenAvailRect)) {
  91     return GetTopWindowInnerRectForRFP();
  92   }
  93
  94   // Here we manipulate the value of aRect to represent the screen size,
  95   // if in RDM.
  96   if (nsPIDOMWindowInner* owner = GetOwnerWindow()) {
  97     if (Document* doc = owner->GetExtantDoc()) {
  98       Maybe<CSSIntSize> deviceSize =
  99           nsGlobalWindowOuter::GetRDMDeviceSize(*doc);
 100       if (deviceSize.isSome()) {
 101         const CSSIntSize& size = deviceSize.value();
 102         return {0, 0, size.width, size.height};
 103       }
 104     }
 105   }
 106
 107   nsDeviceContext* context = GetDeviceContext();
 108   if (NS_WARN_IF(!context)) {
 109     return {};
 110   }
 111   return CSSIntRect::FromAppUnitsRounded(context->GetClientRect());
 112 }
 113
 114 uint16_t nsScreen::GetOrientationAngle() const {
 115   nsDeviceContext* context = GetDeviceContext();
 116   if (context) {
 117     return context->GetScreenOrientationAngle();
 118   }
 119   RefPtr<widget::Screen> s =
 120       widget::ScreenManager::GetSingleton().GetPrimaryScreen();
 121   return s->GetOrientationAngle();
 122 }
 123
 124 hal::ScreenOrientation nsScreen::GetOrientationType() const {
 125   nsDeviceContext* context = GetDeviceContext();
 126   if (context) {
 127     return context->GetScreenOrientationType();
 128   }
 129   RefPtr<widget::Screen> s =
 130       widget::ScreenManager::GetSingleton().GetPrimaryScreen();
 131   return s->GetOrientationType();
 132 }
 133
 134 ScreenOrientation* nsScreen::Orientation() const { return mScreenOrientation; }
 135
 136 void nsScreen::GetMozOrientation(nsString& aOrientation,
 137                                  CallerType aCallerType) const {
 138   switch (mScreenOrientation->DeviceType(aCallerType)) {
 139     case OrientationType::Portrait_primary:
 140       aOrientation.AssignLiteral("portrait-primary");
 141       break;
 142     case OrientationType::Portrait_secondary:
 143       aOrientation.AssignLiteral("portrait-secondary");
 144       break;
 145     case OrientationType::Landscape_primary:
 146       aOrientation.AssignLiteral("landscape-primary");
 147       break;
 148     case OrientationType::Landscape_secondary:
 149       aOrientation.AssignLiteral("landscape-secondary");
 150       break;
 151     default:
 152       MOZ_CRASH("Unacceptable screen orientation type.");
 153   }
 154 }
 155
 156 /* virtual */
 157 JSObject* nsScreen::WrapObject(JSContext* aCx,
 158                                JS::Handle<JSObject*> aGivenProto) {
 159   return Screen_Binding::Wrap(aCx, this, aGivenProto);
 160 }
 161
 162 CSSIntRect nsScreen::GetTopWindowInnerRectForRFP() {
 163   if (nsPIDOMWindowInner* inner = GetOwnerWindow()) {
 164     if (BrowsingContext* bc = inner->GetBrowsingContext()) {
 165       CSSIntSize size = bc->Top()->GetTopInnerSizeForRFP();
 166       return {0, 0, size.width, size.height};
 167     }
 168   }
 169   return {};
 170 }
 171
 172 bool nsScreen::ShouldResistFingerprinting(RFPTarget aTarget) const {
 173   nsGlobalWindowInner* owner = GetOwnerWindow();
 174   return owner && owner->ShouldResistFingerprinting(aTarget);
 175 }