1 /* 2 Copyright (C) 2004, 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann (at) kde.org> 3 2004, 2005, 2006, 2007 Rob Buis <buis (at) kde.org> 4 Copyright (C) Research In Motion Limited 2009-2010. All rights reserved. 5 6 This library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Library General Public 8 License as published by the Free Software Foundation; either 9 version 2 of the License, or (at your option) any later version. 10 11 This library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Library General Public License for more details. 15 16 You should have received a copy of the GNU Library General Public License 17 along with this library; see the file COPYING.LIB. If not, write to 18 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 Boston, MA 02110-1301, USA. 20 */ 21 22 #include "config.h" 23 24 #if ENABLE(SVG) 25 #include "SVGUseElement.h" 26 27 #include "CSSStyleSelector.h" 28 #include "CString.h" 29 #include "Document.h" 30 #include "Event.h" 31 #include "EventListener.h" 32 #include "HTMLNames.h" 33 #include "MappedAttribute.h" 34 #include "NodeRenderStyle.h" 35 #include "RegisteredEventListener.h" 36 #include "RenderSVGShadowTreeRootContainer.h" 37 #include "SVGElementInstance.h" 38 #include "SVGElementInstanceList.h" 39 #include "SVGGElement.h" 40 #include "SVGLength.h" 41 #include "SVGPreserveAspectRatio.h" 42 #include "SVGShadowTreeElements.h" 43 #include "SVGSMILElement.h" 44 #include "SVGSVGElement.h" 45 #include "SVGSymbolElement.h" 46 #include "XLinkNames.h" 47 #include "XMLSerializer.h" 48 49 // Dump SVGElementInstance object tree - useful to debug instanceRoot problems 50 // #define DUMP_INSTANCE_TREE 51 52 // Dump the deep-expanded shadow tree (where the renderers are built from) 53 // #define DUMP_SHADOW_TREE 54 55 namespace WebCore { 56 57 SVGUseElement::SVGUseElement(const QualifiedName& tagName, Document* doc) 58 : SVGStyledTransformableElement(tagName, doc) 59 , SVGTests() 60 , SVGLangSpace() 61 , SVGExternalResourcesRequired() 62 , SVGURIReference() 63 , m_x(LengthModeWidth) 64 , m_y(LengthModeHeight) 65 , m_width(LengthModeWidth) 66 , m_height(LengthModeHeight) 67 , m_isPendingResource(false) 68 , m_needsShadowTreeRecreation(false) 69 { 70 } 71 72 SVGUseElement::~SVGUseElement() 73 { 74 } 75 76 SVGElementInstance* SVGUseElement::instanceRoot() const 77 { 78 // If there is no element instance tree, force immediate SVGElementInstance tree 79 // creation by asking the document to invoke our recalcStyle function - as we can't 80 // wait for the lazy creation to happen if e.g. JS wants to access the instanceRoot 81 // object right after creating the element on-the-fly 82 if (!m_targetElementInstance) 83 document()->updateLayoutIgnorePendingStylesheets(); 84 85 return m_targetElementInstance.get(); 86 } 87 88 SVGElementInstance* SVGUseElement::animatedInstanceRoot() const 89 { 90 // FIXME: Implement me. 91 return 0; 92 } 93 94 void SVGUseElement::parseMappedAttribute(MappedAttribute* attr) 95 { 96 if (attr->name() == SVGNames::xAttr) 97 setXBaseValue(SVGLength(LengthModeWidth, attr->value())); 98 else if (attr->name() == SVGNames::yAttr) 99 setYBaseValue(SVGLength(LengthModeHeight, attr->value())); 100 else if (attr->name() == SVGNames::widthAttr) { 101 setWidthBaseValue(SVGLength(LengthModeWidth, attr->value())); 102 if (widthBaseValue().value(this) < 0.0) 103 document()->accessSVGExtensions()->reportError("A negative value for use attribute <width> is not allowed"); 104 } else if (attr->name() == SVGNames::heightAttr) { 105 setHeightBaseValue(SVGLength(LengthModeHeight, attr->value())); 106 if (heightBaseValue().value(this) < 0.0) 107 document()->accessSVGExtensions()->reportError("A negative value for use attribute <height> is not allowed"); 108 } else { 109 if (SVGTests::parseMappedAttribute(attr)) 110 return; 111 if (SVGLangSpace::parseMappedAttribute(attr)) 112 return; 113 if (SVGExternalResourcesRequired::parseMappedAttribute(attr)) 114 return; 115 if (SVGURIReference::parseMappedAttribute(attr)) 116 return; 117 SVGStyledTransformableElement::parseMappedAttribute(attr); 118 } 119 } 120 121 void SVGUseElement::insertedIntoDocument() 122 { 123 // This functions exists to assure assumptions made in the code regarding SVGElementInstance creation/destruction are satisfied. 124 SVGElement::insertedIntoDocument(); 125 ASSERT(!m_targetElementInstance); 126 ASSERT(!m_isPendingResource); 127 } 128 129 void SVGUseElement::removedFromDocument() 130 { 131 m_targetElementInstance = 0; 132 SVGElement::removedFromDocument(); 133 } 134 135 void SVGUseElement::svgAttributeChanged(const QualifiedName& attrName) 136 { 137 SVGStyledTransformableElement::svgAttributeChanged(attrName); 138 139 if (!renderer()) 140 return; 141 142 if (SVGURIReference::isKnownAttribute(attrName)) { 143 if (m_isPendingResource) { 144 document()->accessSVGExtensions()->removePendingResource(m_resourceId); 145 m_resourceId = String(); 146 m_isPendingResource = false; 147 } 148 149 invalidateShadowTree(); 150 return; 151 } 152 153 if (attrName == SVGNames::xAttr || attrName == SVGNames::yAttr) { 154 updateContainerOffsets(); 155 return; 156 } 157 158 if (attrName == SVGNames::widthAttr || attrName == SVGNames::heightAttr) { 159 updateContainerSizes(); 160 return; 161 } 162 163 // Be very careful here, if svgAttributeChanged() has been called because a SVG CSS property changed, we do NOT want to reclone the tree! 164 if (SVGStyledElement::isKnownAttribute(attrName)) { 165 setNeedsStyleRecalc(); 166 return; 167 } 168 169 if (SVGTests::isKnownAttribute(attrName) 170 || SVGLangSpace::isKnownAttribute(attrName) 171 || SVGExternalResourcesRequired::isKnownAttribute(attrName) 172 || SVGStyledTransformableElement::isKnownAttribute(attrName)) { 173 invalidateShadowTree(); 174 } 175 } 176 177 void SVGUseElement::synchronizeProperty(const QualifiedName& attrName) 178 { 179 SVGStyledTransformableElement::synchronizeProperty(attrName); 180 181 if (attrName == anyQName()) { 182 synchronizeX(); 183 synchronizeY(); 184 synchronizeWidth(); 185 synchronizeHeight(); 186 synchronizeExternalResourcesRequired(); 187 synchronizeHref(); 188 return; 189 } 190 191 if (attrName == SVGNames::xAttr) 192 synchronizeX(); 193 else if (attrName == SVGNames::yAttr) 194 synchronizeY(); 195 else if (attrName == SVGNames::widthAttr) 196 synchronizeWidth(); 197 else if (attrName == SVGNames::heightAttr) 198 synchronizeHeight(); 199 else if (SVGExternalResourcesRequired::isKnownAttribute(attrName)) 200 synchronizeExternalResourcesRequired(); 201 else if (SVGURIReference::isKnownAttribute(attrName)) 202 synchronizeHref(); 203 } 204 205 static void updateContainerSize(SVGUseElement* useElement, SVGElementInstance* targetInstance) 206 { 207 // Depth-first used to write the method in early exit style, no particular other reason. 208 for (SVGElementInstance* instance = targetInstance->firstChild(); instance; instance = instance->nextSibling()) 209 updateContainerSize(useElement, instance); 210 211 SVGElement* correspondingElement = targetInstance->correspondingElement(); 212 ASSERT(correspondingElement); 213 214 bool isSymbolTag = correspondingElement->hasTagName(SVGNames::symbolTag); 215 if (!correspondingElement->hasTagName(SVGNames::svgTag) && !isSymbolTag) 216 return; 217 218 SVGElement* shadowTreeElement = targetInstance->shadowTreeElement(); 219 ASSERT(shadowTreeElement); 220 ASSERT(shadowTreeElement->hasTagName(SVGNames::svgTag)); 221 222 // Spec (<use> on <symbol>): This generated 'svg' will always have explicit values for attributes width and height. 223 // If attributes width and/or height are provided on the 'use' element, then these attributes 224 // will be transferred to the generated 'svg'. If attributes width and/or height are not specified, 225 // the generated 'svg' element will use values of 100% for these attributes. 226 227 // Spec (<use> on <svg>): If attributes width and/or height are provided on the 'use' element, then these 228 // values will override the corresponding attributes on the 'svg' in the generated tree. 229 230 if (useElement->hasAttribute(SVGNames::widthAttr)) 231 shadowTreeElement->setAttribute(SVGNames::widthAttr, useElement->getAttribute(SVGNames::widthAttr)); 232 else if (isSymbolTag && shadowTreeElement->hasAttribute(SVGNames::widthAttr)) 233 shadowTreeElement->setAttribute(SVGNames::widthAttr, "100%"); 234 235 if (useElement->hasAttribute(SVGNames::heightAttr)) 236 shadowTreeElement->setAttribute(SVGNames::heightAttr, useElement->getAttribute(SVGNames::heightAttr)); 237 else if (isSymbolTag && shadowTreeElement->hasAttribute(SVGNames::heightAttr)) 238 shadowTreeElement->setAttribute(SVGNames::heightAttr, "100%"); 239 } 240 241 void SVGUseElement::updateContainerSizes() 242 { 243 if (!m_targetElementInstance) 244 return; 245 246 // Update whole subtree, scanning for shadow container elements, that correspond to <svg>/<symbol> tags 247 updateContainerSize(this, m_targetElementInstance.get()); 248 249 if (renderer()) 250 renderer()->setNeedsLayout(true); 251 } 252 253 static void updateContainerOffset(SVGElementInstance* targetInstance) 254 { 255 // Depth-first used to write the method in early exit style, no particular other reason. 256 for (SVGElementInstance* instance = targetInstance->firstChild(); instance; instance = instance->nextSibling()) 257 updateContainerOffset(instance); 258 259 SVGElement* correspondingElement = targetInstance->correspondingElement(); 260 ASSERT(correspondingElement); 261 262 if (!correspondingElement->hasTagName(SVGNames::useTag)) 263 return; 264 265 SVGElement* shadowTreeElement = targetInstance->shadowTreeElement(); 266 ASSERT(shadowTreeElement); 267 ASSERT(shadowTreeElement->hasTagName(SVGNames::gTag)); 268 269 if (!static_cast<SVGGElement*>(shadowTreeElement)->isShadowTreeContainerElement()) 270 return; 271 272 // Spec: An additional transformation translate(x,y) is appended to the end 273 // (i.e., right-side) of the transform attribute on the generated 'g', where x 274 // and y represent the values of the x and y attributes on the 'use' element. 275 SVGUseElement* useElement = static_cast<SVGUseElement*>(correspondingElement); 276 SVGShadowTreeContainerElement* containerElement = static_cast<SVGShadowTreeContainerElement*>(shadowTreeElement); 277 containerElement->setContainerOffset(useElement->x(), useElement->y()); 278 } 279 280 void SVGUseElement::updateContainerOffsets() 281 { 282 if (!m_targetElementInstance) 283 return; 284 285 // Update root container offset (not reachable through instance tree) 286 SVGElement* shadowRoot = m_targetElementInstance->shadowTreeElement(); 287 ASSERT(shadowRoot); 288 289 Node* parentNode = shadowRoot->parentNode(); 290 ASSERT(parentNode); 291 ASSERT(parentNode->isSVGElement()); 292 ASSERT(parentNode->hasTagName(SVGNames::gTag)); 293 ASSERT(static_cast<SVGGElement*>(parentNode)->isShadowTreeContainerElement()); 294 295 SVGShadowTreeContainerElement* containerElement = static_cast<SVGShadowTreeContainerElement*>(parentNode); 296 containerElement->setContainerOffset(x(), y()); 297 298 // Update whole subtree, scanning for shadow container elements, marking a cloned use subtree 299 updateContainerOffset(m_targetElementInstance.get()); 300 301 if (renderer()) 302 renderer()->setNeedsLayout(true); 303 } 304 305 void SVGUseElement::recalcStyle(StyleChange change) 306 { 307 // Eventually mark shadow root element needing style recalc 308 if (needsStyleRecalc() && m_targetElementInstance) { 309 if (SVGElement* shadowRoot = m_targetElementInstance->shadowTreeElement()) 310 shadowRoot->setNeedsStyleRecalc(); 311 } 312 313 SVGStyledTransformableElement::recalcStyle(change); 314 315 bool needsStyleUpdate = !m_needsShadowTreeRecreation; 316 if (m_needsShadowTreeRecreation) { 317 static_cast<RenderSVGShadowTreeRootContainer*>(renderer())->markShadowTreeForRecreation(); 318 m_needsShadowTreeRecreation = false; 319 } 320 321 RenderSVGShadowTreeRootContainer* shadowRoot = static_cast<RenderSVGShadowTreeRootContainer*>(renderer()); 322 if (!shadowRoot) 323 return; 324 325 shadowRoot->updateFromElement(); 326 327 if (!needsStyleUpdate) 328 return; 329 330 shadowRoot->updateStyle(change); 331 } 332 333 #ifdef DUMP_INSTANCE_TREE 334 void dumpInstanceTree(unsigned int& depth, String& text, SVGElementInstance* targetInstance) 335 { 336 SVGElement* element = targetInstance->correspondingElement(); 337 ASSERT(element); 338 339 SVGElement* shadowTreeElement = targetInstance->shadowTreeElement(); 340 ASSERT(shadowTreeElement); 341 342 String elementId = element->getIDAttribute(); 343 String elementNodeName = element->nodeName(); 344 String shadowTreeElementNodeName = shadowTreeElement->nodeName(); 345 String parentNodeName = element->parentNode() ? element->parentNode()->nodeName() : "null"; 346 String firstChildNodeName = element->firstChild() ? element->firstChild()->nodeName() : "null"; 347 348 for (unsigned int i = 0; i < depth; ++i) 349 text += " "; 350 351 text += String::format("SVGElementInstance this=%p, (parentNode=%s (%p), firstChild=%s (%p), correspondingElement=%s (%p), shadowTreeElement=%s (%p), id=%s)\n", 352 targetInstance, parentNodeName.latin1().data(), element->parentNode(), firstChildNodeName.latin1().data(), element->firstChild(), 353 elementNodeName.latin1().data(), element, shadowTreeElementNodeName.latin1().data(), shadowTreeElement, elementId.latin1().data()); 354 355 for (unsigned int i = 0; i < depth; ++i) 356 text += " "; 357 358 const HashSet<SVGElementInstance*>& elementInstances = element->instancesForElement(); 359 text += String::format("Corresponding element is associated with %i instance(s):\n", elementInstances.size()); 360 361 const HashSet<SVGElementInstance*>::const_iterator end = elementInstances.end(); 362 for (HashSet<SVGElementInstance*>::const_iterator it = elementInstances.begin(); it != end; ++it) { 363 for (unsigned int i = 0; i < depth; ++i) 364 text += " "; 365 366 text += String::format(" -> SVGElementInstance this=%p, (refCount: %i, shadowTreeElement in document? %i)\n", 367 *it, (*it)->refCount(), (*it)->shadowTreeElement()->inDocument()); 368 } 369 370 ++depth; 371 372 for (SVGElementInstance* instance = targetInstance->firstChild(); instance; instance = instance->nextSibling()) 373 dumpInstanceTree(depth, text, instance); 374 375 --depth; 376 } 377 #endif 378 379 static bool isDisallowedElement(Node* element) 380 { 381 #if ENABLE(SVG_FOREIGN_OBJECT) 382 // <foreignObject> should never be contained in a <use> tree. Too dangerous side effects possible. 383 if (element->hasTagName(SVGNames::foreignObjectTag)) 384 return true; 385 #endif 386 #if ENABLE(SVG_ANIMATION) 387 if (SVGSMILElement::isSMILElement(element)) 388 return true; 389 #endif 390 391 return false; 392 } 393 394 static bool subtreeContainsDisallowedElement(Node* start) 395 { 396 if (isDisallowedElement(start)) 397 return true; 398 399 for (Node* cur = start->firstChild(); cur; cur = cur->nextSibling()) { 400 if (subtreeContainsDisallowedElement(cur)) 401 return true; 402 } 403 404 return false; 405 } 406 407 void SVGUseElement::buildPendingResource() 408 { 409 // If we're called the first time (during shadow tree root creation from RenderSVGShadowTreeRootContainer) 410 // we either determine that our target is available or not - then we add ourselves to the pending resource list 411 // Once the pending resource appears, it will call buildPendingResource(), so we're called a second time. 412 String id = SVGURIReference::getTarget(href()); 413 Element* targetElement = document()->getElementById(id); 414 ASSERT(!m_targetElementInstance); 415 416 if (!targetElement) { 417 if (m_isPendingResource) 418 return; 419 420 m_isPendingResource = true; 421 m_resourceId = id; 422 document()->accessSVGExtensions()->addPendingResource(id, this); 423 return; 424 } 425 426 if (m_isPendingResource) { 427 ASSERT(!m_targetElementInstance); 428 m_isPendingResource = false; 429 invalidateShadowTree(); 430 } 431 } 432 433 void SVGUseElement::buildShadowAndInstanceTree(SVGShadowTreeRootElement* shadowRoot) 434 { 435 String id = SVGURIReference::getTarget(href()); 436 Element* targetElement = document()->getElementById(id); 437 ASSERT(targetElement); 438 439 // Do not build the shadow/instance tree for <use> elements living in a shadow tree. 440 // The will be expanded soon anyway - see expandUseElementsInShadowTree(). 441 Node* parent = parentNode(); 442 while (parent) { 443 if (parent->isShadowNode()) 444 return; 445 446 parent = parent->parentNode(); 447 } 448 449 SVGElement* target = 0; 450 if (targetElement && targetElement->isSVGElement()) 451 target = static_cast<SVGElement*>(targetElement); 452 453 if (m_targetElementInstance) 454 m_targetElementInstance = 0; 455 456 // Do not allow self-referencing. 457 // 'target' may be null, if it's a non SVG namespaced element. 458 if (!target || target == this) 459 return; 460 461 // Why a seperated instance/shadow tree? SVG demands it: 462 // The instance tree is accesable from JavaScript, and has to 463 // expose a 1:1 copy of the referenced tree, whereas internally we need 464 // to alter the tree for correct "use-on-symbol", "use-on-svg" support. 465 466 // Build instance tree. Create root SVGElementInstance object for the first sub-tree node. 467 // 468 // Spec: If the 'use' element references a simple graphics element such as a 'rect', then there is only a 469 // single SVGElementInstance object, and the correspondingElement attribute on this SVGElementInstance object 470 // is the SVGRectElement that corresponds to the referenced 'rect' element. 471 m_targetElementInstance = SVGElementInstance::create(this, target); 472 473 // Eventually enter recursion to build SVGElementInstance objects for the sub-tree children 474 bool foundProblem = false; 475 buildInstanceTree(target, m_targetElementInstance.get(), foundProblem); 476 477 // SVG specification does not say a word about <use> & cycles. My view on this is: just ignore it! 478 // Non-appearing <use> content is easier to debug, then half-appearing content. 479 if (foundProblem) { 480 m_targetElementInstance = 0; 481 return; 482 } 483 484 // Assure instance tree building was successfull 485 ASSERT(m_targetElementInstance); 486 ASSERT(!m_targetElementInstance->shadowTreeElement()); 487 ASSERT(m_targetElementInstance->correspondingUseElement() == this); 488 ASSERT(m_targetElementInstance->correspondingElement() == target); 489 490 // Build shadow tree from instance tree 491 // This also handles the special cases: <use> on <symbol>, <use> on <svg>. 492 buildShadowTree(shadowRoot, target, m_targetElementInstance.get()); 493 494 #if ENABLE(SVG) && ENABLE(SVG_USE) 495 // Expand all <use> elements in the shadow tree. 496 // Expand means: replace the actual <use> element by what it references. 497 expandUseElementsInShadowTree(shadowRoot, shadowRoot); 498 499 // Expand all <symbol> elements in the shadow tree. 500 // Expand means: replace the actual <symbol> element by the <svg> element. 501 expandSymbolElementsInShadowTree(shadowRoot, shadowRoot); 502 #endif 503 504 // Now that the shadow tree is completly expanded, we can associate 505 // shadow tree elements <-> instances in the instance tree. 506 associateInstancesWithShadowTreeElements(shadowRoot->firstChild(), m_targetElementInstance.get()); 507 508 // If no shadow tree element is present, this means that the reference root 509 // element was removed, as it is disallowed (ie. <use> on <foreignObject>) 510 // Do NOT leave an inconsistent instance tree around, instead destruct it. 511 if (!m_targetElementInstance->shadowTreeElement()) { 512 shadowRoot->removeAllChildren(); 513 m_targetElementInstance = 0; 514 return; 515 } 516 517 // Consistency checks - this is assumed in updateContainerOffset(). 518 ASSERT(m_targetElementInstance->shadowTreeElement()->parentNode() == shadowRoot); 519 520 // Eventually dump instance tree 521 #ifdef DUMP_INSTANCE_TREE 522 String text; 523 unsigned int depth = 0; 524 525 dumpInstanceTree(depth, text, m_targetElementInstance.get()); 526 fprintf(stderr, "\nDumping <use> instance tree:\n%s\n", text.latin1().data()); 527 #endif 528 529 // Eventually dump shadow tree 530 #ifdef DUMP_SHADOW_TREE 531 ExceptionCode ec = 0; 532 533 PassRefPtr<XMLSerializer> serializer = XMLSerializer::create(); 534 535 String markup = serializer->serializeToString(shadowRoot, ec); 536 ASSERT(!ec); 537 538 fprintf(stderr, "Dumping <use> shadow tree markup:\n%s\n", markup.latin1().data()); 539 #endif 540 541 // Transfer event listeners assigned to the referenced element to our shadow tree elements. 542 transferEventListenersToShadowTree(m_targetElementInstance.get()); 543 544 // Update container offset/size 545 updateContainerOffsets(); 546 updateContainerSizes(); 547 } 548 549 RenderObject* SVGUseElement::createRenderer(RenderArena* arena, RenderStyle*) 550 { 551 return new (arena) RenderSVGShadowTreeRootContainer(this); 552 } 553 554 static void updateFromElementCallback(Node* node) 555 { 556 if (RenderObject* renderer = node->renderer()) 557 renderer->updateFromElement(); 558 } 559 560 void SVGUseElement::attach() 561 { 562 SVGStyledTransformableElement::attach(); 563 564 if (renderer()) 565 queuePostAttachCallback(updateFromElementCallback, this); 566 } 567 568 void SVGUseElement::detach() 569 { 570 SVGStyledTransformableElement::detach(); 571 m_targetElementInstance = 0; 572 } 573 574 static bool isDirectReference(Node* n) 575 { 576 return n->hasTagName(SVGNames::pathTag) || 577 n->hasTagName(SVGNames::rectTag) || 578 n->hasTagName(SVGNames::circleTag) || 579 n->hasTagName(SVGNames::ellipseTag) || 580 n->hasTagName(SVGNames::polygonTag) || 581 n->hasTagName(SVGNames::polylineTag) || 582 n->hasTagName(SVGNames::textTag); 583 } 584 585 Path SVGUseElement::toClipPath() const 586 { 587 Node* n = m_targetElementInstance ? m_targetElementInstance->shadowTreeElement() : 0; 588 if (!n) 589 return Path(); 590 591 if (n->isSVGElement() && static_cast<SVGElement*>(n)->isStyledTransformable()) { 592 if (!isDirectReference(n)) 593 // Spec: Indirect references are an error (14.3.5) 594 document()->accessSVGExtensions()->reportError("Not allowed to use indirect reference in <clip-path>"); 595 else 596 return static_cast<SVGStyledTransformableElement*>(n)->toClipPath(); 597 } 598 599 return Path(); 600 } 601 602 void SVGUseElement::buildInstanceTree(SVGElement* target, SVGElementInstance* targetInstance, bool& foundProblem) 603 { 604 ASSERT(target); 605 ASSERT(targetInstance); 606 607 // A general description from the SVG spec, describing what buildInstanceTree() actually does. 608 // 609 // Spec: If the 'use' element references a 'g' which contains two 'rect' elements, then the instance tree 610 // contains three SVGElementInstance objects, a root SVGElementInstance object whose correspondingElement 611 // is the SVGGElement object for the 'g', and then two child SVGElementInstance objects, each of which has 612 // its correspondingElement that is an SVGRectElement object. 613 614 for (Node* node = target->firstChild(); node; node = node->nextSibling()) { 615 SVGElement* element = 0; 616 if (node->isSVGElement()) 617 element = static_cast<SVGElement*>(node); 618 619 // Skip any non-svg nodes or any disallowed element. 620 if (!element || isDisallowedElement(element)) 621 continue; 622 623 // Create SVGElementInstance object, for both container/non-container nodes. 624 RefPtr<SVGElementInstance> instance = SVGElementInstance::create(this, element); 625 SVGElementInstance* instancePtr = instance.get(); 626 targetInstance->appendChild(instance.release()); 627 628 // Enter recursion, appending new instance tree nodes to the "instance" object. 629 buildInstanceTree(element, instancePtr, foundProblem); 630 } 631 632 // Spec: If the referenced object is itself a 'use', or if there are 'use' subelements within the referenced 633 // object, the instance tree will contain recursive expansion of the indirect references to form a complete tree. 634 if (target->hasTagName(SVGNames::useTag)) 635 handleDeepUseReferencing(static_cast<SVGUseElement*>(target), targetInstance, foundProblem); 636 } 637 638 void SVGUseElement::handleDeepUseReferencing(SVGUseElement* use, SVGElementInstance* targetInstance, bool& foundProblem) 639 { 640 String id = SVGURIReference::getTarget(use->href()); 641 Element* targetElement = document()->getElementById(id); 642 SVGElement* target = 0; 643 if (targetElement && targetElement->isSVGElement()) 644 target = static_cast<SVGElement*>(targetElement); 645 646 if (!target) 647 return; 648 649 // Cycle detection first! 650 foundProblem = (target == this); 651 652 // Shortcut for self-references 653 if (foundProblem) 654 return; 655 656 SVGElementInstance* instance = targetInstance->parentNode(); 657 while (instance) { 658 SVGElement* element = instance->correspondingElement(); 659 660 if (element->getIDAttribute() == id) { 661 foundProblem = true; 662 return; 663 } 664 665 instance = instance->parentNode(); 666 } 667 668 // Create an instance object, even if we're dealing with a cycle 669 RefPtr<SVGElementInstance> newInstance = SVGElementInstance::create(this, target); 670 SVGElementInstance* newInstancePtr = newInstance.get(); 671 targetInstance->appendChild(newInstance.release()); 672 673 // Eventually enter recursion to build SVGElementInstance objects for the sub-tree children 674 buildInstanceTree(target, newInstancePtr, foundProblem); 675 } 676 677 void SVGUseElement::removeDisallowedElementsFromSubtree(Node* subtree) 678 { 679 ASSERT(!subtree->inDocument()); 680 ExceptionCode ec; 681 Node* node = subtree->firstChild(); 682 while (node) { 683 if (isDisallowedElement(node)) { 684 Node* next = node->traverseNextSibling(subtree); 685 // The subtree is not in document so this won't generate events that could mutate the tree. 686 node->parent()->removeChild(node, ec); 687 node = next; 688 } else 689 node = node->traverseNextNode(subtree); 690 } 691 } 692 693 void SVGUseElement::buildShadowTree(SVGShadowTreeRootElement* shadowRoot, SVGElement* target, SVGElementInstance* targetInstance) 694 { 695 // For instance <use> on <foreignObject> (direct case). 696 if (isDisallowedElement(target)) 697 return; 698 699 RefPtr<Element> newChild = targetInstance->correspondingElement()->cloneElementWithChildren(); 700 701 // We don't walk the target tree element-by-element, and clone each element, 702 // but instead use cloneElementWithChildren(). This is an optimization for the common 703 // case where <use> doesn't contain disallowed elements (ie. <foreignObject>). 704 // Though if there are disallowed elements in the subtree, we have to remove them. 705 // For instance: <use> on <g> containing <foreignObject> (indirect case). 706 if (subtreeContainsDisallowedElement(newChild.get())) 707 removeDisallowedElementsFromSubtree(newChild.get()); 708 709 SVGElement* newChildPtr = 0; 710 if (newChild->isSVGElement()) 711 newChildPtr = static_cast<SVGElement*>(newChild.get()); 712 ASSERT(newChildPtr); 713 714 ExceptionCode ec = 0; 715 shadowRoot->appendChild(newChild.release(), ec); 716 ASSERT(!ec); 717 } 718 719 #if ENABLE(SVG) && ENABLE(SVG_USE) 720 void SVGUseElement::expandUseElementsInShadowTree(SVGShadowTreeRootElement* shadowRoot, Node* element) 721 { 722 // Why expand the <use> elements in the shadow tree here, and not just 723 // do this directly in buildShadowTree, if we encounter a <use> element? 724 // 725 // Short answer: Because we may miss to expand some elements. Ie. if a <symbol> 726 // contains <use> tags, we'd miss them. So once we're done with settin' up the 727 // actual shadow tree (after the special case modification for svg/symbol) we have 728 // to walk it completely and expand all <use> elements. 729 if (element->hasTagName(SVGNames::useTag)) { 730 SVGUseElement* use = static_cast<SVGUseElement*>(element); 731 732 String id = SVGURIReference::getTarget(use->href()); 733 Element* targetElement = document()->getElementById(id); 734 SVGElement* target = 0; 735 if (targetElement && targetElement->isSVGElement()) 736 target = static_cast<SVGElement*>(targetElement); 737 738 // Don't ASSERT(target) here, it may be "pending", too. 739 if (target) { 740 // Setup sub-shadow tree root node 741 RefPtr<SVGShadowTreeContainerElement> cloneParent = new SVGShadowTreeContainerElement(document()); 742 743 // Spec: In the generated content, the 'use' will be replaced by 'g', where all attributes from the 744 // 'use' element except for x, y, width, height and xlink:href are transferred to the generated 'g' element. 745 transferUseAttributesToReplacedElement(use, cloneParent.get()); 746 747 ExceptionCode ec = 0; 748 749 // For instance <use> on <foreignObject> (direct case). 750 if (isDisallowedElement(target)) { 751 // We still have to setup the <use> replacment (<g>). Otherwhise 752 // associateInstancesWithShadowTreeElements() makes wrong assumptions. 753 // Replace <use> with referenced content. 754 ASSERT(use->parentNode()); 755 use->parentNode()->replaceChild(cloneParent.release(), use, ec); 756 ASSERT(!ec); 757 return; 758 } 759 760 RefPtr<Element> newChild = target->cloneElementWithChildren(); 761 762 // We don't walk the target tree element-by-element, and clone each element, 763 // but instead use cloneElementWithChildren(). This is an optimization for the common 764 // case where <use> doesn't contain disallowed elements (ie. <foreignObject>). 765 // Though if there are disallowed elements in the subtree, we have to remove them. 766 // For instance: <use> on <g> containing <foreignObject> (indirect case). 767 if (subtreeContainsDisallowedElement(newChild.get())) 768 removeDisallowedElementsFromSubtree(newChild.get()); 769 770 SVGElement* newChildPtr = 0; 771 if (newChild->isSVGElement()) 772 newChildPtr = static_cast<SVGElement*>(newChild.get()); 773 ASSERT(newChildPtr); 774 775 cloneParent->appendChild(newChild.release(), ec); 776 ASSERT(!ec); 777 778 // Replace <use> with referenced content. 779 ASSERT(use->parentNode()); 780 use->parentNode()->replaceChild(cloneParent.release(), use, ec); 781 ASSERT(!ec); 782 783 // Immediately stop here, and restart expanding. 784 expandUseElementsInShadowTree(shadowRoot, shadowRoot); 785 return; 786 } 787 } 788 789 for (RefPtr<Node> child = element->firstChild(); child; child = child->nextSibling()) 790 expandUseElementsInShadowTree(shadowRoot, child.get()); 791 } 792 793 void SVGUseElement::expandSymbolElementsInShadowTree(SVGShadowTreeRootElement* shadowRoot, Node* element) 794 { 795 if (element->hasTagName(SVGNames::symbolTag)) { 796 // Spec: The referenced 'symbol' and its contents are deep-cloned into the generated tree, 797 // with the exception that the 'symbol' is replaced by an 'svg'. This generated 'svg' will 798 // always have explicit values for attributes width and height. If attributes width and/or 799 // height are provided on the 'use' element, then these attributes will be transferred to 800 // the generated 'svg'. If attributes width and/or height are not specified, the generated 801 // 'svg' element will use values of 100% for these attributes. 802 RefPtr<SVGSVGElement> svgElement = new SVGSVGElement(SVGNames::svgTag, document()); 803 804 // Transfer all attributes from <symbol> to the new <svg> element 805 svgElement->attributes()->setAttributes(*element->attributes()); 806 807 // Only clone symbol children, and add them to the new <svg> element 808 ExceptionCode ec = 0; 809 for (Node* child = element->firstChild(); child; child = child->nextSibling()) { 810 RefPtr<Node> newChild = child->cloneNode(true); 811 svgElement->appendChild(newChild.release(), ec); 812 ASSERT(!ec); 813 } 814 815 // We don't walk the target tree element-by-element, and clone each element, 816 // but instead use cloneNode(deep=true). This is an optimization for the common 817 // case where <use> doesn't contain disallowed elements (ie. <foreignObject>). 818 // Though if there are disallowed elements in the subtree, we have to remove them. 819 // For instance: <use> on <g> containing <foreignObject> (indirect case). 820 if (subtreeContainsDisallowedElement(svgElement.get())) 821 removeDisallowedElementsFromSubtree(svgElement.get()); 822 823 // Replace <symbol> with <svg>. 824 ASSERT(element->parentNode()); 825 element->parentNode()->replaceChild(svgElement.release(), element, ec); 826 ASSERT(!ec); 827 828 // Immediately stop here, and restart expanding. 829 expandSymbolElementsInShadowTree(shadowRoot, shadowRoot); 830 return; 831 } 832 833 for (RefPtr<Node> child = element->firstChild(); child; child = child->nextSibling()) 834 expandSymbolElementsInShadowTree(shadowRoot, child.get()); 835 } 836 837 #endif 838 839 void SVGUseElement::transferEventListenersToShadowTree(SVGElementInstance* target) 840 { 841 if (!target) 842 return; 843 844 SVGElement* originalElement = target->correspondingElement(); 845 ASSERT(originalElement); 846 847 if (SVGElement* shadowTreeElement = target->shadowTreeElement()) { 848 if (EventTargetData* d = originalElement->eventTargetData()) { 849 EventListenerMap& map = d->eventListenerMap; 850 EventListenerMap::iterator end = map.end(); 851 for (EventListenerMap::iterator it = map.begin(); it != end; ++it) { 852 EventListenerVector& entry = *it->second; 853 for (size_t i = 0; i < entry.size(); ++i) { 854 // Event listeners created from markup have already been transfered to the shadow tree during cloning. 855 if (entry[i].listener->wasCreatedFromMarkup()) 856 continue; 857 shadowTreeElement->addEventListener(it->first, entry[i].listener, entry[i].useCapture); 858 } 859 } 860 } 861 } 862 863 for (SVGElementInstance* instance = target->firstChild(); instance; instance = instance->nextSibling()) 864 transferEventListenersToShadowTree(instance); 865 } 866 867 void SVGUseElement::associateInstancesWithShadowTreeElements(Node* target, SVGElementInstance* targetInstance) 868 { 869 if (!target || !targetInstance) 870 return; 871 872 SVGElement* originalElement = targetInstance->correspondingElement(); 873 874 if (originalElement->hasTagName(SVGNames::useTag)) { 875 #if ENABLE(SVG) && ENABLE(SVG_USE) 876 // <use> gets replaced by <g> 877 ASSERT(target->nodeName() == SVGNames::gTag); 878 #else 879 ASSERT(target->nodeName() == SVGNames::gTag || target->nodeName() == SVGNames::useTag); 880 #endif 881 } else if (originalElement->hasTagName(SVGNames::symbolTag)) { 882 // <symbol> gets replaced by <svg> 883 #if ENABLE(SVG) && ENABLE(SVG_USE) && ENABLE(SVG_FOREIGN_OBJECT) 884 ASSERT(target->nodeName() == SVGNames::svgTag); 885 #endif 886 } else 887 ASSERT(target->nodeName() == originalElement->nodeName()); 888 889 SVGElement* element = 0; 890 if (target->isSVGElement()) 891 element = static_cast<SVGElement*>(target); 892 893 ASSERT(!targetInstance->shadowTreeElement()); 894 targetInstance->setShadowTreeElement(element); 895 896 Node* node = target->firstChild(); 897 for (SVGElementInstance* instance = targetInstance->firstChild(); node && instance; instance = instance->nextSibling()) { 898 // Skip any non-svg elements in shadow tree 899 while (node && !node->isSVGElement()) 900 node = node->nextSibling(); 901 902 associateInstancesWithShadowTreeElements(node, instance); 903 node = node->nextSibling(); 904 } 905 } 906 907 SVGElementInstance* SVGUseElement::instanceForShadowTreeElement(Node* element) const 908 { 909 if (!m_targetElementInstance) { 910 ASSERT(!inDocument()); 911 return 0; 912 } 913 914 return instanceForShadowTreeElement(element, m_targetElementInstance.get()); 915 } 916 917 SVGElementInstance* SVGUseElement::instanceForShadowTreeElement(Node* element, SVGElementInstance* instance) const 918 { 919 ASSERT(element); 920 ASSERT(instance); 921 922 // We're dispatching a mutation event during shadow tree construction 923 // this instance hasn't yet been associated to a shadowTree element. 924 if (!instance->shadowTreeElement()) 925 return 0; 926 927 if (element == instance->shadowTreeElement()) 928 return instance; 929 930 for (SVGElementInstance* current = instance->firstChild(); current; current = current->nextSibling()) { 931 if (SVGElementInstance* search = instanceForShadowTreeElement(element, current)) 932 return search; 933 } 934 935 return 0; 936 } 937 938 void SVGUseElement::invalidateShadowTree() 939 { 940 m_needsShadowTreeRecreation = true; 941 setNeedsStyleRecalc(); 942 } 943 944 void SVGUseElement::transferUseAttributesToReplacedElement(SVGElement* from, SVGElement* to) const 945 { 946 ASSERT(from); 947 ASSERT(to); 948 949 to->attributes()->setAttributes(*from->attributes()); 950 951 ExceptionCode ec = 0; 952 953 to->removeAttribute(SVGNames::xAttr, ec); 954 ASSERT(!ec); 955 956 to->removeAttribute(SVGNames::yAttr, ec); 957 ASSERT(!ec); 958 959 to->removeAttribute(SVGNames::widthAttr, ec); 960 ASSERT(!ec); 961 962 to->removeAttribute(SVGNames::heightAttr, ec); 963 ASSERT(!ec); 964 965 to->removeAttribute(XLinkNames::hrefAttr, ec); 966 ASSERT(!ec); 967 } 968 969 bool SVGUseElement::hasRelativeValues() const 970 { 971 return x().isRelative() || y().isRelative() || width().isRelative() || height().isRelative(); 972 } 973 974 } 975 976 #endif // ENABLE(SVG) 977
