The Tor Browser: layout/xul/nsResizerFrame.cpp@ac0c01689b40 (annotated)

layout/xul/nsResizerFrame.cpp@ac0c01689b40 (annotated)

layout/xul/nsResizerFrame.cpp

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 2; 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 "nsCOMPtr.h"
 #include "nsIServiceManager.h"
 #include "nsResizerFrame.h"
 #include "nsIContent.h"
 #include "nsIDocument.h"
 #include "nsIDOMNodeList.h"
 #include "nsGkAtoms.h"
 #include "nsNameSpaceManager.h"
 #include "nsIDOMElementCSSInlineStyle.h"
 #include "nsIDOMCSSStyleDeclaration.h"
 #include "nsPresContext.h"
 #include "nsFrameManager.h"
 #include "nsIDocShell.h"
 #include "nsIDocShellTreeOwner.h"
 #include "nsIBaseWindow.h"
 #include "nsPIDOMWindow.h"
 #include "mozilla/MouseEvents.h"
 #include "nsContentUtils.h"
 #include "nsMenuPopupFrame.h"
 #include "nsIScreenManager.h"
 #include "mozilla/dom/Element.h"
 #include "nsError.h"
 #include <algorithm>
 using namespace mozilla;
 //
 // NS_NewResizerFrame
 //
 // Creates a new Resizer frame and returns it
 //
 nsIFrame*
 NS_NewResizerFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 {
   return new (aPresShell) nsResizerFrame(aPresShell, aContext);
 }
 NS_IMPL_FRAMEARENA_HELPERS(nsResizerFrame)
 nsResizerFrame::nsResizerFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 :nsTitleBarFrame(aPresShell, aContext)
 {
 }
 nsresult
 nsResizerFrame::HandleEvent(nsPresContext* aPresContext,
                             WidgetGUIEvent* aEvent,
                             nsEventStatus* aEventStatus)
 {
   NS_ENSURE_ARG_POINTER(aEventStatus);
   if (nsEventStatus_eConsumeNoDefault == *aEventStatus) {
     return NS_OK;
   }
   nsWeakFrame weakFrame(this);
   bool doDefault = true;
   switch (aEvent->message) {
     case NS_TOUCH_START:
     case NS_MOUSE_BUTTON_DOWN: {
       if (aEvent->eventStructType == NS_TOUCH_EVENT ||
           (aEvent->eventStructType == NS_MOUSE_EVENT &&
            aEvent->AsMouseEvent()->button == WidgetMouseEvent::eLeftButton)) {
         nsCOMPtr<nsIBaseWindow> window;
         nsIPresShell* presShell = aPresContext->GetPresShell();
         nsIContent* contentToResize =
           GetContentToResize(presShell, getter_AddRefs(window));
         if (contentToResize) {
           nsIFrame* frameToResize = contentToResize->GetPrimaryFrame();
           if (!frameToResize)
             break;
           // cache the content rectangle for the frame to resize
           // GetScreenRectInAppUnits returns the border box rectangle, so
           // adjust to get the desired content rectangle.
           nsRect rect = frameToResize->GetScreenRectInAppUnits();
           switch (frameToResize->StylePosition()->mBoxSizing) {
             case NS_STYLE_BOX_SIZING_CONTENT:
               rect.Deflate(frameToResize->GetUsedPadding());
             case NS_STYLE_BOX_SIZING_PADDING:
               rect.Deflate(frameToResize->GetUsedBorder());
             default:
               break;
           }
           mMouseDownRect = rect.ToNearestPixels(aPresContext->AppUnitsPerDevPixel());
           doDefault = false;
         }
         else {
           // If there is no window, then resizing isn't allowed.
           if (!window)
             break;
           doDefault = false;
           // ask the widget implementation to begin a resize drag if it can
           Direction direction = GetDirection();
           nsresult rv = aEvent->widget->BeginResizeDrag(aEvent,
                         direction.mHorizontal, direction.mVertical);
           // for native drags, don't set the fields below
           if (rv != NS_ERROR_NOT_IMPLEMENTED)
              break;
           // if there's no native resize support, we need to do window
           // resizing ourselves
           window->GetPositionAndSize(&mMouseDownRect.x, &mMouseDownRect.y,
                                      &mMouseDownRect.width, &mMouseDownRect.height);
         }
         // remember current mouse coordinates
         nsIntPoint refPoint;
         if (!GetEventPoint(aEvent, refPoint))
           return NS_OK;
         mMouseDownPoint = refPoint + aEvent->widget->WidgetToScreenOffset();
         // we're tracking
         mTrackingMouseMove = true;
         nsIPresShell::SetCapturingContent(GetContent(), CAPTURE_IGNOREALLOWED);
       }
     }
     break;
   case NS_TOUCH_END:
   case NS_MOUSE_BUTTON_UP: {
     if (aEvent->eventStructType == NS_TOUCH_EVENT ||
         (aEvent->eventStructType == NS_MOUSE_EVENT &&
          aEvent->AsMouseEvent()->button == WidgetMouseEvent::eLeftButton)) {
       // we're done tracking.
       mTrackingMouseMove = false;
       nsIPresShell::SetCapturingContent(nullptr, 0);
       doDefault = false;
     }
   }
   break;
   case NS_TOUCH_MOVE:
   case NS_MOUSE_MOVE: {
     if (mTrackingMouseMove)
     {
       nsCOMPtr<nsIBaseWindow> window;
       nsIPresShell* presShell = aPresContext->GetPresShell();
       nsCOMPtr<nsIContent> contentToResize =
         GetContentToResize(presShell, getter_AddRefs(window));
       // check if the returned content really is a menupopup
       nsMenuPopupFrame* menuPopupFrame = nullptr;
       if (contentToResize) {
         menuPopupFrame = do_QueryFrame(contentToResize->GetPrimaryFrame());
       }
       // both MouseMove and direction are negative when pointing to the
       // top and left, and positive when pointing to the bottom and right
       // retrieve the offset of the mousemove event relative to the mousedown.
       // The difference is how much the resize needs to be
       nsIntPoint refPoint;
       if (!GetEventPoint(aEvent, refPoint))
         return NS_OK;
       nsIntPoint screenPoint(refPoint + aEvent->widget->WidgetToScreenOffset());
       nsIntPoint mouseMove(screenPoint - mMouseDownPoint);
       // Determine which direction to resize by checking the dir attribute.
       // For windows and menus, ensure that it can be resized in that direction.
       Direction direction = GetDirection();
       if (window || menuPopupFrame) {
         if (menuPopupFrame) {
           menuPopupFrame->CanAdjustEdges(
             (direction.mHorizontal == -1) ? NS_SIDE_LEFT : NS_SIDE_RIGHT,
             (direction.mVertical == -1) ? NS_SIDE_TOP : NS_SIDE_BOTTOM, mouseMove);
         }
       }
       else if (!contentToResize) {
         break; // don't do anything if there's nothing to resize
       }
       nsIntRect rect = mMouseDownRect;
       // Check if there are any size constraints on this window.
       widget::SizeConstraints sizeConstraints;
       if (window) {
         nsCOMPtr<nsIWidget> widget;
         window->GetMainWidget(getter_AddRefs(widget));
         sizeConstraints = widget->GetSizeConstraints();
       }
       AdjustDimensions(&rect.x, &rect.width, sizeConstraints.mMinSize.width,
                        sizeConstraints.mMaxSize.width, mouseMove.x, direction.mHorizontal);
       AdjustDimensions(&rect.y, &rect.height, sizeConstraints.mMinSize.height,
                        sizeConstraints.mMaxSize.height, mouseMove.y, direction.mVertical);
       // Don't allow resizing a window or a popup past the edge of the screen,
       // so adjust the rectangle to fit within the available screen area.
       if (window) {
         nsCOMPtr<nsIScreen> screen;
         nsCOMPtr<nsIScreenManager> sm(do_GetService("@mozilla.org/gfx/screenmanager;1"));
         if (sm) {
           nsIntRect frameRect = GetScreenRect();
           // ScreenForRect requires display pixels, so scale from device pix
           double scale;
           window->GetUnscaledDevicePixelsPerCSSPixel(&scale);
           sm->ScreenForRect(NSToIntRound(frameRect.x / scale),
                             NSToIntRound(frameRect.y / scale), 1, 1,
                             getter_AddRefs(screen));
           if (screen) {
             nsIntRect screenRect;
             screen->GetRect(&screenRect.x, &screenRect.y,
                             &screenRect.width, &screenRect.height);
             rect.IntersectRect(rect, screenRect);
           }
         }
       }
       else if (menuPopupFrame) {
         nsRect frameRect = menuPopupFrame->GetScreenRectInAppUnits();
         nsIFrame* rootFrame = aPresContext->PresShell()->FrameManager()->GetRootFrame();
         nsRect rootScreenRect = rootFrame->GetScreenRectInAppUnits();
         nsPopupLevel popupLevel = menuPopupFrame->PopupLevel();
         nsRect screenRect = menuPopupFrame->GetConstraintRect(frameRect, rootScreenRect, popupLevel);
         // round using ToInsidePixels as it's better to be a pixel too small
         // than be too large. If the popup is too large it could get flipped
         // to the opposite side of the anchor point while resizing.
         nsIntRect screenRectPixels = screenRect.ToInsidePixels(aPresContext->AppUnitsPerDevPixel());
         rect.IntersectRect(rect, screenRectPixels);
       }
       if (contentToResize) {
         // convert the rectangle into css pixels. When changing the size in a
         // direction, don't allow the new size to be less that the resizer's
         // size. This ensures that content isn't resized too small as to make
         // the resizer invisible.
         nsRect appUnitsRect = rect.ToAppUnits(aPresContext->AppUnitsPerDevPixel());
         if (appUnitsRect.width < mRect.width && mouseMove.x)
           appUnitsRect.width = mRect.width;
         if (appUnitsRect.height < mRect.height && mouseMove.y)
           appUnitsRect.height = mRect.height;
         nsIntRect cssRect = appUnitsRect.ToInsidePixels(nsPresContext::AppUnitsPerCSSPixel());
         nsIntRect oldRect;
         nsWeakFrame weakFrame(menuPopupFrame);
         if (menuPopupFrame) {
           nsCOMPtr<nsIWidget> widget = menuPopupFrame->GetWidget();
           if (widget)
             widget->GetScreenBounds(oldRect);
           // convert the new rectangle into outer window coordinates
           nsIntPoint clientOffset = widget->GetClientOffset();
           rect.x -= clientOffset.x;
           rect.y -= clientOffset.y;
         }
         SizeInfo sizeInfo, originalSizeInfo;
         sizeInfo.width.AppendInt(cssRect.width);
         sizeInfo.height.AppendInt(cssRect.height);
         ResizeContent(contentToResize, direction, sizeInfo, &originalSizeInfo);
         MaybePersistOriginalSize(contentToResize, originalSizeInfo);
         // Move the popup to the new location unless it is anchored, since
         // the position shouldn't change. nsMenuPopupFrame::SetPopupPosition
         // will instead ensure that the popup's position is anchored at the
         // right place.
         if (weakFrame.IsAlive() &&
             (oldRect.x != rect.x || oldRect.y != rect.y) &&
             (!menuPopupFrame->IsAnchored() ||
              menuPopupFrame->PopupLevel() != ePopupLevelParent)) {
           rect.x = aPresContext->DevPixelsToIntCSSPixels(rect.x);
           rect.y = aPresContext->DevPixelsToIntCSSPixels(rect.y);
           menuPopupFrame->MoveTo(rect.x, rect.y, true);
         }
       }
       else {
         window->SetPositionAndSize(rect.x, rect.y, rect.width, rect.height, true); // do the repaint.
       }
       doDefault = false;
     }
   }
   break;
   case NS_MOUSE_CLICK: {
     WidgetMouseEvent* mouseEvent = aEvent->AsMouseEvent();
     if (mouseEvent->IsLeftClickEvent()) {
       MouseClicked(aPresContext, mouseEvent);
     }
     break;
   }
   case NS_MOUSE_DOUBLECLICK:
     if (aEvent->AsMouseEvent()->button == WidgetMouseEvent::eLeftButton) {
       nsCOMPtr<nsIBaseWindow> window;
       nsIPresShell* presShell = aPresContext->GetPresShell();
       nsIContent* contentToResize =
         GetContentToResize(presShell, getter_AddRefs(window));
       if (contentToResize) {
         nsMenuPopupFrame* menuPopupFrame = do_QueryFrame(contentToResize->GetPrimaryFrame());
         if (menuPopupFrame)
           break; // Don't restore original sizing for menupopup frames until
                  // we handle screen constraints here. (Bug 357725)
         RestoreOriginalSize(contentToResize);
       }
     }
     break;
   }
   if (!doDefault)
     *aEventStatus = nsEventStatus_eConsumeNoDefault;
   if (doDefault && weakFrame.IsAlive())
     return nsTitleBarFrame::HandleEvent(aPresContext, aEvent, aEventStatus);
   return NS_OK;
 }
 nsIContent*
 nsResizerFrame::GetContentToResize(nsIPresShell* aPresShell, nsIBaseWindow** aWindow)
 {
   *aWindow = nullptr;
   nsAutoString elementid;
   mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::element, elementid);
   if (elementid.IsEmpty()) {
     // If the resizer is in a popup, resize the popup's widget, otherwise
     // resize the widget associated with the window.
     nsIFrame* popup = GetParent();
     while (popup) {
       nsMenuPopupFrame* popupFrame = do_QueryFrame(popup);
       if (popupFrame) {
         return popupFrame->GetContent();
       }
       popup = popup->GetParent();
     }
     // don't allow resizing windows in content shells
     nsCOMPtr<nsIDocShellTreeItem> dsti = aPresShell->GetPresContext()->GetDocShell();
     if (!dsti || dsti->ItemType() != nsIDocShellTreeItem::typeChrome) {
       // don't allow resizers in content shells, except for the viewport
       // scrollbar which doesn't have a parent
       nsIContent* nonNativeAnon = mContent->FindFirstNonChromeOnlyAccessContent();
       if (!nonNativeAnon || nonNativeAnon->GetParent()) {
         return nullptr;
       }
     }
     // get the document and the window - should this be cached?
     nsPIDOMWindow *domWindow = aPresShell->GetDocument()->GetWindow();
     if (domWindow) {
       nsCOMPtr<nsIDocShell> docShell = domWindow->GetDocShell();
       if (docShell) {
         nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
         docShell->GetTreeOwner(getter_AddRefs(treeOwner));
         if (treeOwner) {
           CallQueryInterface(treeOwner, aWindow);
         }
       }
     }
     return nullptr;
   }
   if (elementid.EqualsLiteral("_parent")) {
     // return the parent, but skip over native anonymous content
     nsIContent* parent = mContent->GetParent();
     return parent ? parent->FindFirstNonChromeOnlyAccessContent() : nullptr;
   }
   return aPresShell->GetDocument()->GetElementById(elementid);
 }
 void
 nsResizerFrame::AdjustDimensions(int32_t* aPos, int32_t* aSize,
                                  int32_t aMinSize, int32_t aMaxSize,
                                  int32_t aMovement, int8_t aResizerDirection)
 {
   int32_t oldSize = *aSize;
   *aSize += aResizerDirection * aMovement;
   // use one as a minimum size or the element could disappear
   if (*aSize < 1)
     *aSize = 1;
   // Constrain the size within the minimum and maximum size.
   *aSize = std::max(aMinSize, std::min(aMaxSize, *aSize));
   // For left and top resizers, the window must be moved left by the same
   // amount that the window was resized.
   if (aResizerDirection == -1)
     *aPos += oldSize - *aSize;
 }
 /* static */ void
 nsResizerFrame::ResizeContent(nsIContent* aContent, const Direction& aDirection,
                               const SizeInfo& aSizeInfo, SizeInfo* aOriginalSizeInfo)
 {
   // for XUL elements, just set the width and height attributes. For
   // other elements, set style.width and style.height
   if (aContent->IsXUL()) {
     if (aOriginalSizeInfo) {
       aContent->GetAttr(kNameSpaceID_None, nsGkAtoms::width,
                         aOriginalSizeInfo->width);
       aContent->GetAttr(kNameSpaceID_None, nsGkAtoms::height,
                         aOriginalSizeInfo->height);
     }
     // only set the property if the element could have changed in that direction
     if (aDirection.mHorizontal) {
       aContent->SetAttr(kNameSpaceID_None, nsGkAtoms::width, aSizeInfo.width, true);
     }
     if (aDirection.mVertical) {
       aContent->SetAttr(kNameSpaceID_None, nsGkAtoms::height, aSizeInfo.height, true);
     }
   }
   else {
     nsCOMPtr<nsIDOMElementCSSInlineStyle> inlineStyleContent =
       do_QueryInterface(aContent);
     if (inlineStyleContent) {
       nsCOMPtr<nsIDOMCSSStyleDeclaration> decl;
       inlineStyleContent->GetStyle(getter_AddRefs(decl));
       if (aOriginalSizeInfo) {
         decl->GetPropertyValue(NS_LITERAL_STRING("width"),
                                aOriginalSizeInfo->width);
         decl->GetPropertyValue(NS_LITERAL_STRING("height"),
                                aOriginalSizeInfo->height);
       }
       // only set the property if the element could have changed in that direction
       if (aDirection.mHorizontal) {
         nsAutoString widthstr(aSizeInfo.width);
         if (!widthstr.IsEmpty() &&
             !Substring(widthstr, widthstr.Length() - 2, 2).EqualsLiteral("px"))
           widthstr.AppendLiteral("px");
         decl->SetProperty(NS_LITERAL_STRING("width"), widthstr, EmptyString());
       }
       if (aDirection.mVertical) {
         nsAutoString heightstr(aSizeInfo.height);
         if (!heightstr.IsEmpty() &&
             !Substring(heightstr, heightstr.Length() - 2, 2).EqualsLiteral("px"))
           heightstr.AppendLiteral("px");
         decl->SetProperty(NS_LITERAL_STRING("height"), heightstr, EmptyString());
       }
     }
   }
 }
 /* static */ void
 nsResizerFrame::MaybePersistOriginalSize(nsIContent* aContent,
                                          const SizeInfo& aSizeInfo)
 {
   nsresult rv;
   aContent->GetProperty(nsGkAtoms::_moz_original_size, &rv);
   if (rv != NS_PROPTABLE_PROP_NOT_THERE)
     return;
   nsAutoPtr<SizeInfo> sizeInfo(new SizeInfo(aSizeInfo));
   rv = aContent->SetProperty(nsGkAtoms::_moz_original_size, sizeInfo.get(),
                              nsINode::DeleteProperty<nsResizerFrame::SizeInfo>);
   if (NS_SUCCEEDED(rv))
     sizeInfo.forget();
 }
 /* static */ void
 nsResizerFrame::RestoreOriginalSize(nsIContent* aContent)
 {
   nsresult rv;
   SizeInfo* sizeInfo =
     static_cast<SizeInfo*>(aContent->GetProperty(nsGkAtoms::_moz_original_size,
                            &rv));
   if (NS_FAILED(rv))
     return;
   NS_ASSERTION(sizeInfo, "We set a null sizeInfo!?");
   Direction direction = {1, 1};
   ResizeContent(aContent, direction, *sizeInfo, nullptr);
   aContent->DeleteProperty(nsGkAtoms::_moz_original_size);
 }
 /* returns a Direction struct containing the horizontal and vertical direction
  */
 nsResizerFrame::Direction
 nsResizerFrame::GetDirection()
 {
   static const nsIContent::AttrValuesArray strings[] =
     {&nsGkAtoms::topleft,    &nsGkAtoms::top,    &nsGkAtoms::topright,
      &nsGkAtoms::left,                           &nsGkAtoms::right,
      &nsGkAtoms::bottomleft, &nsGkAtoms::bottom, &nsGkAtoms::bottomright,
      &nsGkAtoms::bottomstart,                    &nsGkAtoms::bottomend,
      nullptr};
   static const Direction directions[] =
     {{-1, -1}, {0, -1}, {1, -1},
      {-1,  0},          {1,  0},
      {-1,  1}, {0,  1}, {1,  1},
      {-1,  1},          {1,  1}
     };
   if (!GetContent())
     return directions[0]; // default: topleft
   int32_t index = GetContent()->FindAttrValueIn(kNameSpaceID_None,
                                                 nsGkAtoms::dir,
                                                 strings, eCaseMatters);
   if(index < 0)
     return directions[0]; // default: topleft
   else if (index >= 8 && StyleVisibility()->mDirection == NS_STYLE_DIRECTION_RTL) {
     // Directions 8 and higher are RTL-aware directions and should reverse the
     // horizontal component if RTL.
     Direction direction = directions[index];
     direction.mHorizontal *= -1;
     return direction;
   }
   return directions[index];
 }
 void
 nsResizerFrame::MouseClicked(nsPresContext* aPresContext,
                              WidgetMouseEvent* aEvent)
 {
   // Execute the oncommand event handler.
   nsContentUtils::DispatchXULCommand(mContent,
                                      aEvent && aEvent->mFlags.mIsTrusted);
 }

The Tor Browser / annotate

layout/xul/nsResizerFrame.cpp@ac0c01689b40 (annotated)

layout/xul/nsResizerFrame.cpp