1 /* 2 * Copyright (C) 2011 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include "config.h" 32 #include "IFrameShimSupport.h" 33 34 #include "Element.h" 35 #include "FrameView.h" 36 #include "HTMLElement.h" 37 #include "HTMLFrameOwnerElement.h" 38 #include "HTMLNames.h" 39 #include "RenderBox.h" 40 #include "RenderObject.h" 41 #include "Widget.h" 42 43 #include <wtf/HashSet.h> 44 45 // This file provides plugin-related utility functions for iframe shims and is shared by platforms that inherit 46 // from PluginView (e.g. Qt) and those that do not (e.g. Chromium). 47 48 namespace WebCore { 49 50 static void getObjectStack(const RenderObject* ro, Vector<const RenderObject*>* roStack) 51 { 52 roStack->clear(); 53 while (ro) { 54 roStack->append(ro); 55 ro = ro->parent(); 56 } 57 } 58 59 // Returns true if stack1 is at or above stack2 60 static bool iframeIsAbovePlugin(const Vector<const RenderObject*>& iframeZstack, const Vector<const RenderObject*>& pluginZstack) 61 { 62 for (size_t i = 0; i < iframeZstack.size() && i < pluginZstack.size(); i++) { 63 // The root is at the end of these stacks. We want to iterate 64 // root-downwards so we index backwards from the end. 65 const RenderObject* ro1 = iframeZstack[iframeZstack.size() - 1 - i]; 66 const RenderObject* ro2 = pluginZstack[pluginZstack.size() - 1 - i]; 67 68 if (ro1 != ro2) { 69 // When we find nodes in the stack that are not the same, then 70 // we've found the nodes just below the lowest comment ancestor. 71 // Determine which should be on top. 72 73 // See if z-index determines an order. 74 if (ro1->style() && ro2->style()) { 75 int z1 = ro1->style()->zIndex(); 76 int z2 = ro2->style()->zIndex(); 77 if (z1 > z2) 78 return true; 79 if (z1 < z2) 80 return false; 81 } 82 83 // If the plugin does not have an explicit z-index it stacks behind the iframe. 84 // This is for maintaining compatibility with IE. 85 if (ro2->style()->position() == StaticPosition) { 86 // The 0'th elements of these RenderObject arrays represent the plugin node and 87 // the iframe. 88 const RenderObject* pluginRenderObject = pluginZstack[0]; 89 const RenderObject* iframeRenderObject = iframeZstack[0]; 90 91 if (pluginRenderObject->style() && iframeRenderObject->style()) { 92 if (pluginRenderObject->style()->zIndex() > iframeRenderObject->style()->zIndex()) 93 return false; 94 } 95 return true; 96 } 97 98 // Inspect the document order. Later order means higher stacking. 99 const RenderObject* parent = ro1->parent(); 100 if (!parent) 101 return false; 102 ASSERT(parent == ro2->parent()); 103 104 for (const RenderObject* ro = parent->firstChild(); ro; ro = ro->nextSibling()) { 105 if (ro == ro1) 106 return false; 107 if (ro == ro2) 108 return true; 109 } 110 ASSERT(false); // We should have seen ro1 and ro2 by now. 111 return false; 112 } 113 } 114 return true; 115 } 116 117 // Return a set of rectangles that should not be overdrawn by the 118 // plugin ("cutouts"). This helps implement the "iframe shim" 119 // technique of overlaying a windowed plugin with content from the 120 // page. In a nutshell, iframe elements should occlude plugins when 121 // they occur higher in the stacking order. 122 void getPluginOcclusions(Element* element, Widget* parentWidget, const IntRect& frameRect, Vector<IntRect>& occlusions) 123 { 124 RenderObject* pluginNode = element->renderer(); 125 ASSERT(pluginNode); 126 if (!pluginNode->style()) 127 return; 128 Vector<const RenderObject*> pluginZstack; 129 Vector<const RenderObject*> iframeZstack; 130 getObjectStack(pluginNode, &pluginZstack); 131 132 if (!parentWidget->isFrameView()) 133 return; 134 135 FrameView* parentFrameView = static_cast<FrameView*>(parentWidget); 136 137 const HashSet<RefPtr<Widget> >* children = parentFrameView->children(); 138 for (HashSet<RefPtr<Widget> >::const_iterator it = children->begin(); it != children->end(); ++it) { 139 // We only care about FrameView's because iframes show up as FrameViews. 140 if (!(*it)->isFrameView()) 141 continue; 142 143 const FrameView* frameView = static_cast<const FrameView*>((*it).get()); 144 // Check to make sure we can get both the element and the RenderObject 145 // for this FrameView, if we can't just move on to the next object. 146 if (!frameView->frame() || !frameView->frame()->ownerElement() 147 || !frameView->frame()->ownerElement()->renderer()) 148 continue; 149 150 HTMLElement* element = frameView->frame()->ownerElement(); 151 RenderObject* iframeRenderer = element->renderer(); 152 153 if (element->hasTagName(HTMLNames::iframeTag) 154 && iframeRenderer->absoluteBoundingBoxRect().intersects(frameRect) 155 && (!iframeRenderer->style() || iframeRenderer->style()->visibility() == VISIBLE)) { 156 getObjectStack(iframeRenderer, &iframeZstack); 157 if (iframeIsAbovePlugin(iframeZstack, pluginZstack)) { 158 IntPoint point = roundedIntPoint(iframeRenderer->localToAbsolute()); 159 RenderBox* rbox = toRenderBox(iframeRenderer); 160 IntSize size(rbox->width(), rbox->height()); 161 occlusions.append(IntRect(point, size)); 162 } 163 } 164 } 165 } 166 167 } // namespace WebCore 168