1 /* 2 * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org) 3 * (C) 2004-2005 Allan Sandfeld Jensen (kde (at) carewolf.com) 4 * Copyright (C) 2006, 2007 Nicholas Shanks (webkit (at) nickshanks.com) 5 * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved. 6 * Copyright (C) 2007 Alexey Proskuryakov <ap (at) webkit.org> 7 * Copyright (C) 2007, 2008 Eric Seidel <eric (at) webkit.org> 8 * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/) 9 * Copyright (c) 2011, Code Aurora Forum. All rights reserved. 10 * Copyright (C) Research In Motion Limited 2011. All rights reserved. 11 * Copyright (C) 2013 Google Inc. All rights reserved. 12 * 13 * This library is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU Library General Public 15 * License as published by the Free Software Foundation; either 16 * version 2 of the License, or (at your option) any later version. 17 * 18 * This library is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 * Library General Public License for more details. 22 * 23 * You should have received a copy of the GNU Library General Public License 24 * along with this library; see the file COPYING.LIB. If not, write to 25 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 26 * Boston, MA 02110-1301, USA. 27 */ 28 29 #include "config.h" 30 #include "core/css/resolver/StyleAdjuster.h" 31 32 #include "HTMLNames.h" 33 #include "SVGNames.h" 34 #include "core/dom/ContainerNode.h" 35 #include "core/dom/Document.h" 36 #include "core/dom/Element.h" 37 #include "core/html/HTMLHtmlElement.h" 38 #include "core/html/HTMLIFrameElement.h" 39 #include "core/html/HTMLInputElement.h" 40 #include "core/html/HTMLTableElement.h" 41 #include "core/html/HTMLTextAreaElement.h" 42 #include "core/page/FrameView.h" 43 #include "core/page/Page.h" 44 #include "core/page/Settings.h" 45 #include "core/platform/Length.h" 46 #include "core/rendering/Pagination.h" 47 #include "core/rendering/RenderTheme.h" 48 #include "core/rendering/style/GridPosition.h" 49 #include "core/rendering/style/RenderStyle.h" 50 #include "core/rendering/style/RenderStyleConstants.h" 51 #include "wtf/Assertions.h" 52 53 namespace WebCore { 54 55 using namespace HTMLNames; 56 57 // FIXME: This is duplicated with StyleResolver.cpp 58 // Perhaps this should move onto ElementResolveContext or even Element? 59 static inline bool isAtShadowBoundary(const Element* element) 60 { 61 if (!element) 62 return false; 63 ContainerNode* parentNode = element->parentNode(); 64 return parentNode && parentNode->isShadowRoot(); 65 } 66 67 68 static void addIntrinsicMargins(RenderStyle* style) 69 { 70 // Intrinsic margin value. 71 const int intrinsicMargin = 2 * style->effectiveZoom(); 72 73 // FIXME: Using width/height alone and not also dealing with min-width/max-width is flawed. 74 // FIXME: Using "quirk" to decide the margin wasn't set is kind of lame. 75 if (style->width().isIntrinsicOrAuto()) { 76 if (style->marginLeft().quirk()) 77 style->setMarginLeft(Length(intrinsicMargin, Fixed)); 78 if (style->marginRight().quirk()) 79 style->setMarginRight(Length(intrinsicMargin, Fixed)); 80 } 81 82 if (style->height().isAuto()) { 83 if (style->marginTop().quirk()) 84 style->setMarginTop(Length(intrinsicMargin, Fixed)); 85 if (style->marginBottom().quirk()) 86 style->setMarginBottom(Length(intrinsicMargin, Fixed)); 87 } 88 } 89 90 static EDisplay equivalentBlockDisplay(EDisplay display, bool isFloating, bool strictParsing) 91 { 92 switch (display) { 93 case BLOCK: 94 case TABLE: 95 case BOX: 96 case FLEX: 97 case GRID: 98 case LAZY_BLOCK: 99 return display; 100 101 case LIST_ITEM: 102 // It is a WinIE bug that floated list items lose their bullets, so we'll emulate the quirk, but only in quirks mode. 103 if (!strictParsing && isFloating) 104 return BLOCK; 105 return display; 106 case INLINE_TABLE: 107 return TABLE; 108 case INLINE_BOX: 109 return BOX; 110 case INLINE_FLEX: 111 return FLEX; 112 case INLINE_GRID: 113 return GRID; 114 115 case INLINE: 116 case RUN_IN: 117 case COMPACT: 118 case INLINE_BLOCK: 119 case TABLE_ROW_GROUP: 120 case TABLE_HEADER_GROUP: 121 case TABLE_FOOTER_GROUP: 122 case TABLE_ROW: 123 case TABLE_COLUMN_GROUP: 124 case TABLE_COLUMN: 125 case TABLE_CELL: 126 case TABLE_CAPTION: 127 return BLOCK; 128 case NONE: 129 ASSERT_NOT_REACHED(); 130 return NONE; 131 } 132 ASSERT_NOT_REACHED(); 133 return BLOCK; 134 } 135 136 // CSS requires text-decoration to be reset at each DOM element for tables, 137 // inline blocks, inline tables, run-ins, shadow DOM crossings, floating elements, 138 // and absolute or relatively positioned elements. 139 static bool doesNotInheritTextDecoration(const RenderStyle* style, const Element* e) 140 { 141 return style->display() == TABLE || style->display() == INLINE_TABLE || style->display() == RUN_IN 142 || style->display() == INLINE_BLOCK || style->display() == INLINE_BOX || isAtShadowBoundary(e) 143 || style->isFloating() || style->hasOutOfFlowPosition(); 144 } 145 146 // FIXME: This helper is only needed because pseudoStyleForElement passes a null 147 // element to adjustRenderStyle, so we can't just use element->isInTopLayer(). 148 static bool isInTopLayer(const Element* element, const RenderStyle* style) 149 { 150 return (element && element->isInTopLayer()) || (style && style->styleType() == BACKDROP); 151 } 152 153 static bool isDisplayFlexibleBox(EDisplay display) 154 { 155 return display == FLEX || display == INLINE_FLEX; 156 } 157 158 static bool isDisplayGridBox(EDisplay display) 159 { 160 return display == GRID || display == INLINE_GRID; 161 } 162 163 void StyleAdjuster::adjustRenderStyle(RenderStyle* style, RenderStyle* parentStyle, Element *e) 164 { 165 ASSERT(parentStyle); 166 167 // Cache our original display. 168 style->setOriginalDisplay(style->display()); 169 170 if (style->display() != NONE) { 171 // If we have a <td> that specifies a float property, in quirks mode we just drop the float 172 // property. 173 // Sites also commonly use display:inline/block on <td>s and <table>s. In quirks mode we force 174 // these tags to retain their display types. 175 if (m_useQuirksModeStyles && e) { 176 if (e->hasTagName(tdTag)) { 177 style->setDisplay(TABLE_CELL); 178 style->setFloating(NoFloat); 179 } else if (isHTMLTableElement(e)) { 180 style->setDisplay(style->isDisplayInlineType() ? INLINE_TABLE : TABLE); 181 } 182 } 183 184 if (e && (e->hasTagName(tdTag) || e->hasTagName(thTag))) { 185 if (style->whiteSpace() == KHTML_NOWRAP) { 186 // Figure out if we are really nowrapping or if we should just 187 // use normal instead. If the width of the cell is fixed, then 188 // we don't actually use NOWRAP. 189 if (style->width().isFixed()) 190 style->setWhiteSpace(NORMAL); 191 else 192 style->setWhiteSpace(NOWRAP); 193 } 194 } 195 196 // Tables never support the -webkit-* values for text-align and will reset back to the default. 197 if (e && isHTMLTableElement(e) && (style->textAlign() == WEBKIT_LEFT || style->textAlign() == WEBKIT_CENTER || style->textAlign() == WEBKIT_RIGHT)) 198 style->setTextAlign(TASTART); 199 200 // Frames and framesets never honor position:relative or position:absolute. This is necessary to 201 // fix a crash where a site tries to position these objects. They also never honor display. 202 if (e && (e->hasTagName(frameTag) || e->hasTagName(framesetTag))) { 203 style->setPosition(StaticPosition); 204 style->setDisplay(BLOCK); 205 } 206 207 // Ruby text does not support float or position. This might change with evolution of the specification. 208 if (e && e->hasTagName(rtTag)) { 209 style->setPosition(StaticPosition); 210 style->setFloating(NoFloat); 211 } 212 213 // FIXME: We shouldn't be overriding start/-webkit-auto like this. Do it in html.css instead. 214 // Table headers with a text-align of -webkit-auto will change the text-align to center. 215 if (e && e->hasTagName(thTag) && style->textAlign() == TASTART) 216 style->setTextAlign(CENTER); 217 218 if (e && e->hasTagName(legendTag)) 219 style->setDisplay(BLOCK); 220 221 // Per the spec, position 'static' and 'relative' in the top layer compute to 'absolute'. 222 if (isInTopLayer(e, style) && (style->position() == StaticPosition || style->position() == RelativePosition)) 223 style->setPosition(AbsolutePosition); 224 225 // Absolute/fixed positioned elements, floating elements and the document element need block-like outside display. 226 if (style->hasOutOfFlowPosition() || style->isFloating() || (e && e->document()->documentElement() == e)) 227 style->setDisplay(equivalentBlockDisplay(style->display(), style->isFloating(), !m_useQuirksModeStyles)); 228 229 // FIXME: Don't support this mutation for pseudo styles like first-letter or first-line, since it's not completely 230 // clear how that should work. 231 if (style->display() == INLINE && style->styleType() == NOPSEUDO && style->writingMode() != parentStyle->writingMode()) 232 style->setDisplay(INLINE_BLOCK); 233 234 // After performing the display mutation, check table rows. We do not honor position:relative or position:sticky on 235 // table rows or cells. This has been established for position:relative in CSS2.1 (and caused a crash in containingBlock() 236 // on some sites). 237 if ((style->display() == TABLE_HEADER_GROUP || style->display() == TABLE_ROW_GROUP 238 || style->display() == TABLE_FOOTER_GROUP || style->display() == TABLE_ROW) 239 && style->hasInFlowPosition()) 240 style->setPosition(StaticPosition); 241 242 // writing-mode does not apply to table row groups, table column groups, table rows, and table columns. 243 // FIXME: Table cells should be allowed to be perpendicular or flipped with respect to the table, though. 244 if (style->display() == TABLE_COLUMN || style->display() == TABLE_COLUMN_GROUP || style->display() == TABLE_FOOTER_GROUP 245 || style->display() == TABLE_HEADER_GROUP || style->display() == TABLE_ROW || style->display() == TABLE_ROW_GROUP 246 || style->display() == TABLE_CELL) 247 style->setWritingMode(parentStyle->writingMode()); 248 249 // FIXME: Since we don't support block-flow on flexible boxes yet, disallow setting 250 // of block-flow to anything other than TopToBottomWritingMode. 251 // https://bugs.webkit.org/show_bug.cgi?id=46418 - Flexible box support. 252 if (style->writingMode() != TopToBottomWritingMode && (style->display() == BOX || style->display() == INLINE_BOX)) 253 style->setWritingMode(TopToBottomWritingMode); 254 255 if (isDisplayFlexibleBox(parentStyle->display()) || isDisplayGridBox(parentStyle->display())) { 256 style->setFloating(NoFloat); 257 style->setDisplay(equivalentBlockDisplay(style->display(), style->isFloating(), !m_useQuirksModeStyles)); 258 } 259 } 260 261 // Make sure our z-index value is only applied if the object is positioned. 262 if (style->position() == StaticPosition && !isDisplayFlexibleBox(parentStyle->display())) 263 style->setHasAutoZIndex(); 264 265 // Auto z-index becomes 0 for the root element and transparent objects. This prevents 266 // cases where objects that should be blended as a single unit end up with a non-transparent 267 // object wedged in between them. Auto z-index also becomes 0 for objects that specify transforms/masks/reflections. 268 if (style->hasAutoZIndex() && ((e && e->document()->documentElement() == e) 269 || style->opacity() < 1.0f 270 || style->hasTransformRelatedProperty() 271 || style->hasMask() 272 || style->clipPath() 273 || style->boxReflect() 274 || style->hasFilter() 275 || style->hasBlendMode() 276 || style->position() == StickyPosition 277 || (style->position() == FixedPosition && e && e->document()->page() && e->document()->page()->settings()->fixedPositionCreatesStackingContext()) 278 || isInTopLayer(e, style) 279 )) 280 style->setZIndex(0); 281 282 // Textarea considers overflow visible as auto. 283 if (e && isHTMLTextAreaElement(e)) { 284 style->setOverflowX(style->overflowX() == OVISIBLE ? OAUTO : style->overflowX()); 285 style->setOverflowY(style->overflowY() == OVISIBLE ? OAUTO : style->overflowY()); 286 } 287 288 // For now, <marquee> requires an overflow clip to work properly. 289 if (e && e->hasTagName(marqueeTag)) { 290 style->setOverflowX(OHIDDEN); 291 style->setOverflowY(OHIDDEN); 292 } 293 294 if (doesNotInheritTextDecoration(style, e)) 295 style->setTextDecorationsInEffect(style->textDecoration()); 296 else 297 style->addToTextDecorationsInEffect(style->textDecoration()); 298 299 // If either overflow value is not visible, change to auto. 300 if (style->overflowX() == OVISIBLE && style->overflowY() != OVISIBLE) { 301 // FIXME: Once we implement pagination controls, overflow-x should default to hidden 302 // if overflow-y is set to -webkit-paged-x or -webkit-page-y. For now, we'll let it 303 // default to auto so we can at least scroll through the pages. 304 style->setOverflowX(OAUTO); 305 } else if (style->overflowY() == OVISIBLE && style->overflowX() != OVISIBLE) { 306 style->setOverflowY(OAUTO); 307 } 308 309 // Call setStylesForPaginationMode() if a pagination mode is set for any non-root elements. If these 310 // styles are specified on a root element, then they will be incorporated in 311 // StyleAdjuster::styleForDocument(). 312 if ((style->overflowY() == OPAGEDX || style->overflowY() == OPAGEDY) && !(e && (isHTMLHtmlElement(e) || e->hasTagName(bodyTag)))) 313 Pagination::setStylesForPaginationMode(WebCore::paginationModeForRenderStyle(style), style); 314 315 // Table rows, sections and the table itself will support overflow:hidden and will ignore scroll/auto. 316 // FIXME: Eventually table sections will support auto and scroll. 317 if (style->display() == TABLE || style->display() == INLINE_TABLE 318 || style->display() == TABLE_ROW_GROUP || style->display() == TABLE_ROW) { 319 if (style->overflowX() != OVISIBLE && style->overflowX() != OHIDDEN) 320 style->setOverflowX(OVISIBLE); 321 if (style->overflowY() != OVISIBLE && style->overflowY() != OHIDDEN) 322 style->setOverflowY(OVISIBLE); 323 } 324 325 // Menulists should have visible overflow 326 if (style->appearance() == MenulistPart) { 327 style->setOverflowX(OVISIBLE); 328 style->setOverflowY(OVISIBLE); 329 } 330 331 // Cull out any useless layers and also repeat patterns into additional layers. 332 style->adjustBackgroundLayers(); 333 style->adjustMaskLayers(); 334 335 // Do the same for animations and transitions. 336 style->adjustAnimations(); 337 style->adjustTransitions(); 338 339 // Important: Intrinsic margins get added to controls before the theme has adjusted the style, since the theme will 340 // alter fonts and heights/widths. 341 if (e && e->isFormControlElement() && style->fontSize() >= 11) { 342 // Don't apply intrinsic margins to image buttons. The designer knows how big the images are, 343 // so we have to treat all image buttons as though they were explicitly sized. 344 if (!e->hasTagName(inputTag) || !toHTMLInputElement(e)->isImageButton()) 345 addIntrinsicMargins(style); 346 } 347 348 // Let the theme also have a crack at adjusting the style. 349 if (style->hasAppearance()) 350 RenderTheme::defaultTheme()->adjustStyle(style, e, m_cachedUAStyle); 351 352 // If we have first-letter pseudo style, do not share this style. 353 if (style->hasPseudoStyle(FIRST_LETTER)) 354 style->setUnique(); 355 356 // FIXME: when dropping the -webkit prefix on transform-style, we should also have opacity < 1 cause flattening. 357 if (style->preserves3D() && (style->overflowX() != OVISIBLE 358 || style->overflowY() != OVISIBLE 359 || style->hasFilter())) 360 style->setTransformStyle3D(TransformStyle3DFlat); 361 362 // Seamless iframes behave like blocks. Map their display to inline-block when marked inline. 363 if (e && e->hasTagName(iframeTag) && style->display() == INLINE && toHTMLIFrameElement(e)->shouldDisplaySeamlessly()) 364 style->setDisplay(INLINE_BLOCK); 365 366 adjustGridItemPosition(style, parentStyle); 367 368 if (e && e->isSVGElement()) { 369 // Spec: http://www.w3.org/TR/SVG/masking.html#OverflowProperty 370 if (style->overflowY() == OSCROLL) 371 style->setOverflowY(OHIDDEN); 372 else if (style->overflowY() == OAUTO) 373 style->setOverflowY(OVISIBLE); 374 375 if (style->overflowX() == OSCROLL) 376 style->setOverflowX(OHIDDEN); 377 else if (style->overflowX() == OAUTO) 378 style->setOverflowX(OVISIBLE); 379 380 // Only the root <svg> element in an SVG document fragment tree honors css position 381 if (!(e->hasTagName(SVGNames::svgTag) && e->parentNode() && !e->parentNode()->isSVGElement())) 382 style->setPosition(RenderStyle::initialPosition()); 383 384 // RenderSVGRoot handles zooming for the whole SVG subtree, so foreignObject content should 385 // not be scaled again. 386 if (e->hasTagName(SVGNames::foreignObjectTag)) 387 style->setEffectiveZoom(RenderStyle::initialZoom()); 388 } 389 } 390 391 void StyleAdjuster::adjustGridItemPosition(RenderStyle* style, RenderStyle* parentStyle) const 392 { 393 const GridPosition& columnStartPosition = style->gridColumnStart(); 394 const GridPosition& columnEndPosition = style->gridColumnEnd(); 395 const GridPosition& rowStartPosition = style->gridRowStart(); 396 const GridPosition& rowEndPosition = style->gridRowEnd(); 397 398 // If opposing grid-placement properties both specify a grid span, they both compute to auto. 399 if (columnStartPosition.isSpan() && columnEndPosition.isSpan()) { 400 style->setGridColumnStart(GridPosition()); 401 style->setGridColumnEnd(GridPosition()); 402 } 403 404 if (rowStartPosition.isSpan() && rowEndPosition.isSpan()) { 405 style->setGridRowStart(GridPosition()); 406 style->setGridRowEnd(GridPosition()); 407 } 408 409 // Unknown named grid area compute to 'auto'. 410 const NamedGridAreaMap& map = parentStyle->namedGridArea(); 411 412 #define CLEAR_UNKNOWN_NAMED_AREA(prop, Prop) \ 413 if (prop.isNamedGridArea() && !map.contains(prop.namedGridLine())) \ 414 style->setGrid##Prop(GridPosition()); 415 416 CLEAR_UNKNOWN_NAMED_AREA(columnStartPosition, ColumnStart); 417 CLEAR_UNKNOWN_NAMED_AREA(columnEndPosition, ColumnEnd); 418 CLEAR_UNKNOWN_NAMED_AREA(rowStartPosition, RowStart); 419 CLEAR_UNKNOWN_NAMED_AREA(rowEndPosition, RowEnd); 420 } 421 422 } 423