1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/base/src/nsStyleLinkElement.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,471 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
1.5 + *
1.6 + * This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +/*
1.11 + * A base class which implements nsIStyleSheetLinkingElement and can
1.12 + * be subclassed by various content nodes that want to load
1.13 + * stylesheets (<style>, <link>, processing instructions, etc).
1.14 + */
1.15 +
1.16 +#include "nsStyleLinkElement.h"
1.17 +
1.18 +#include "mozilla/css/Loader.h"
1.19 +#include "mozilla/dom/Element.h"
1.20 +#include "mozilla/dom/ShadowRoot.h"
1.21 +#include "nsCSSStyleSheet.h"
1.22 +#include "nsIContent.h"
1.23 +#include "nsIDocument.h"
1.24 +#include "nsIDOMComment.h"
1.25 +#include "nsIDOMNode.h"
1.26 +#include "nsIDOMStyleSheet.h"
1.27 +#include "nsNetUtil.h"
1.28 +#include "nsUnicharUtils.h"
1.29 +#include "nsCRT.h"
1.30 +#include "nsXPCOMCIDInternal.h"
1.31 +#include "nsUnicharInputStream.h"
1.32 +#include "nsContentUtils.h"
1.33 +#include "nsStyleUtil.h"
1.34 +
1.35 +using namespace mozilla;
1.36 +using namespace mozilla::dom;
1.37 +
1.38 +nsStyleLinkElement::nsStyleLinkElement()
1.39 + : mDontLoadStyle(false)
1.40 + , mUpdatesEnabled(true)
1.41 + , mLineNumber(1)
1.42 +{
1.43 +}
1.44 +
1.45 +nsStyleLinkElement::~nsStyleLinkElement()
1.46 +{
1.47 + nsStyleLinkElement::SetStyleSheet(nullptr);
1.48 +}
1.49 +
1.50 +void
1.51 +nsStyleLinkElement::Unlink()
1.52 +{
1.53 + mStyleSheet = nullptr;
1.54 +}
1.55 +
1.56 +void
1.57 +nsStyleLinkElement::Traverse(nsCycleCollectionTraversalCallback &cb)
1.58 +{
1.59 + nsStyleLinkElement* tmp = this;
1.60 + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStyleSheet);
1.61 +}
1.62 +
1.63 +NS_IMETHODIMP
1.64 +nsStyleLinkElement::SetStyleSheet(nsCSSStyleSheet* aStyleSheet)
1.65 +{
1.66 + if (mStyleSheet) {
1.67 + mStyleSheet->SetOwningNode(nullptr);
1.68 + }
1.69 +
1.70 + mStyleSheet = aStyleSheet;
1.71 + if (mStyleSheet) {
1.72 + nsCOMPtr<nsINode> node = do_QueryObject(this);
1.73 + if (node) {
1.74 + mStyleSheet->SetOwningNode(node);
1.75 + }
1.76 + }
1.77 +
1.78 + return NS_OK;
1.79 +}
1.80 +
1.81 +NS_IMETHODIMP
1.82 +nsStyleLinkElement::GetStyleSheet(nsIStyleSheet*& aStyleSheet)
1.83 +{
1.84 + aStyleSheet = mStyleSheet;
1.85 + NS_IF_ADDREF(aStyleSheet);
1.86 +
1.87 + return NS_OK;
1.88 +}
1.89 +
1.90 +NS_IMETHODIMP
1.91 +nsStyleLinkElement::InitStyleLinkElement(bool aDontLoadStyle)
1.92 +{
1.93 + mDontLoadStyle = aDontLoadStyle;
1.94 +
1.95 + return NS_OK;
1.96 +}
1.97 +
1.98 +NS_IMETHODIMP
1.99 +nsStyleLinkElement::SetEnableUpdates(bool aEnableUpdates)
1.100 +{
1.101 + mUpdatesEnabled = aEnableUpdates;
1.102 +
1.103 + return NS_OK;
1.104 +}
1.105 +
1.106 +NS_IMETHODIMP
1.107 +nsStyleLinkElement::GetCharset(nsAString& aCharset)
1.108 +{
1.109 + // descendants have to implement this themselves
1.110 + return NS_ERROR_NOT_IMPLEMENTED;
1.111 +}
1.112 +
1.113 +/* virtual */ void
1.114 +nsStyleLinkElement::OverrideBaseURI(nsIURI* aNewBaseURI)
1.115 +{
1.116 + NS_NOTREACHED("Base URI can't be overriden in this implementation "
1.117 + "of nsIStyleSheetLinkingElement.");
1.118 +}
1.119 +
1.120 +/* virtual */ void
1.121 +nsStyleLinkElement::SetLineNumber(uint32_t aLineNumber)
1.122 +{
1.123 + mLineNumber = aLineNumber;
1.124 +}
1.125 +
1.126 +static uint32_t ToLinkMask(const nsAString& aLink)
1.127 +{
1.128 + if (aLink.EqualsLiteral("prefetch"))
1.129 + return nsStyleLinkElement::ePREFETCH;
1.130 + else if (aLink.EqualsLiteral("dns-prefetch"))
1.131 + return nsStyleLinkElement::eDNS_PREFETCH;
1.132 + else if (aLink.EqualsLiteral("stylesheet"))
1.133 + return nsStyleLinkElement::eSTYLESHEET;
1.134 + else if (aLink.EqualsLiteral("next"))
1.135 + return nsStyleLinkElement::eNEXT;
1.136 + else if (aLink.EqualsLiteral("alternate"))
1.137 + return nsStyleLinkElement::eALTERNATE;
1.138 + else
1.139 + return 0;
1.140 +}
1.141 +
1.142 +uint32_t nsStyleLinkElement::ParseLinkTypes(const nsAString& aTypes)
1.143 +{
1.144 + uint32_t linkMask = 0;
1.145 + nsAString::const_iterator start, done;
1.146 + aTypes.BeginReading(start);
1.147 + aTypes.EndReading(done);
1.148 + if (start == done)
1.149 + return linkMask;
1.150 +
1.151 + nsAString::const_iterator current(start);
1.152 + bool inString = !nsContentUtils::IsHTMLWhitespace(*current);
1.153 + nsAutoString subString;
1.154 +
1.155 + while (current != done) {
1.156 + if (nsContentUtils::IsHTMLWhitespace(*current)) {
1.157 + if (inString) {
1.158 + nsContentUtils::ASCIIToLower(Substring(start, current), subString);
1.159 + linkMask |= ToLinkMask(subString);
1.160 + inString = false;
1.161 + }
1.162 + }
1.163 + else {
1.164 + if (!inString) {
1.165 + start = current;
1.166 + inString = true;
1.167 + }
1.168 + }
1.169 + ++current;
1.170 + }
1.171 + if (inString) {
1.172 + nsContentUtils::ASCIIToLower(Substring(start, current), subString);
1.173 + linkMask |= ToLinkMask(subString);
1.174 + }
1.175 + return linkMask;
1.176 +}
1.177 +
1.178 +NS_IMETHODIMP
1.179 +nsStyleLinkElement::UpdateStyleSheet(nsICSSLoaderObserver* aObserver,
1.180 + bool* aWillNotify,
1.181 + bool* aIsAlternate)
1.182 +{
1.183 + return DoUpdateStyleSheet(nullptr, nullptr, aObserver, aWillNotify,
1.184 + aIsAlternate, false);
1.185 +}
1.186 +
1.187 +nsresult
1.188 +nsStyleLinkElement::UpdateStyleSheetInternal(nsIDocument *aOldDocument,
1.189 + ShadowRoot *aOldShadowRoot,
1.190 + bool aForceUpdate)
1.191 +{
1.192 + bool notify, alternate;
1.193 + return DoUpdateStyleSheet(aOldDocument, aOldShadowRoot, nullptr, ¬ify,
1.194 + &alternate, aForceUpdate);
1.195 +}
1.196 +
1.197 +static bool
1.198 +IsScopedStyleElement(nsIContent* aContent)
1.199 +{
1.200 + // This is quicker than, say, QIing aContent to nsStyleLinkElement
1.201 + // and then calling its virtual GetStyleSheetInfo method to find out
1.202 + // if it is scoped.
1.203 + return (aContent->IsHTML(nsGkAtoms::style) ||
1.204 + aContent->IsSVG(nsGkAtoms::style)) &&
1.205 + aContent->HasAttr(kNameSpaceID_None, nsGkAtoms::scoped);
1.206 +}
1.207 +
1.208 +static void
1.209 +SetIsElementInStyleScopeFlagOnSubtree(Element* aElement)
1.210 +{
1.211 + if (aElement->IsElementInStyleScope()) {
1.212 + return;
1.213 + }
1.214 +
1.215 + aElement->SetIsElementInStyleScope();
1.216 +
1.217 + nsIContent* n = aElement->GetNextNode(aElement);
1.218 + while (n) {
1.219 + if (n->IsElementInStyleScope()) {
1.220 + n = n->GetNextNonChildNode(aElement);
1.221 + } else {
1.222 + if (n->IsElement()) {
1.223 + n->SetIsElementInStyleScope();
1.224 + }
1.225 + n = n->GetNextNode(aElement);
1.226 + }
1.227 + }
1.228 +}
1.229 +
1.230 +static bool
1.231 +HasScopedStyleSheetChild(nsIContent* aContent)
1.232 +{
1.233 + for (nsIContent* n = aContent->GetFirstChild(); n; n = n->GetNextSibling()) {
1.234 + if (IsScopedStyleElement(n)) {
1.235 + return true;
1.236 + }
1.237 + }
1.238 + return false;
1.239 +}
1.240 +
1.241 +// Called when aElement has had a <style scoped> child removed.
1.242 +static void
1.243 +UpdateIsElementInStyleScopeFlagOnSubtree(Element* aElement)
1.244 +{
1.245 + NS_ASSERTION(aElement->IsElementInStyleScope(),
1.246 + "only call UpdateIsElementInStyleScopeFlagOnSubtree on a "
1.247 + "subtree that has IsElementInStyleScope boolean flag set");
1.248 +
1.249 + if (HasScopedStyleSheetChild(aElement)) {
1.250 + return;
1.251 + }
1.252 +
1.253 + aElement->ClearIsElementInStyleScope();
1.254 +
1.255 + nsIContent* n = aElement->GetNextNode(aElement);
1.256 + while (n) {
1.257 + if (HasScopedStyleSheetChild(n)) {
1.258 + n = n->GetNextNonChildNode(aElement);
1.259 + } else {
1.260 + if (n->IsElement()) {
1.261 + n->ClearIsElementInStyleScope();
1.262 + }
1.263 + n = n->GetNextNode(aElement);
1.264 + }
1.265 + }
1.266 +}
1.267 +
1.268 +static Element*
1.269 +GetScopeElement(nsIStyleSheet* aSheet)
1.270 +{
1.271 + nsRefPtr<nsCSSStyleSheet> cssStyleSheet = do_QueryObject(aSheet);
1.272 + if (!cssStyleSheet) {
1.273 + return nullptr;
1.274 + }
1.275 +
1.276 + return cssStyleSheet->GetScopeElement();
1.277 +}
1.278 +
1.279 +nsresult
1.280 +nsStyleLinkElement::DoUpdateStyleSheet(nsIDocument* aOldDocument,
1.281 + ShadowRoot* aOldShadowRoot,
1.282 + nsICSSLoaderObserver* aObserver,
1.283 + bool* aWillNotify,
1.284 + bool* aIsAlternate,
1.285 + bool aForceUpdate)
1.286 +{
1.287 + *aWillNotify = false;
1.288 +
1.289 + nsCOMPtr<nsIContent> thisContent;
1.290 + CallQueryInterface(this, getter_AddRefs(thisContent));
1.291 +
1.292 + // All instances of nsStyleLinkElement should implement nsIContent.
1.293 + NS_ENSURE_TRUE(thisContent, NS_ERROR_FAILURE);
1.294 +
1.295 + // Check for a ShadowRoot because link elements are inert in a
1.296 + // ShadowRoot.
1.297 + ShadowRoot* containingShadow = thisContent->GetContainingShadow();
1.298 + if (thisContent->IsHTML(nsGkAtoms::link) &&
1.299 + (aOldShadowRoot || containingShadow)) {
1.300 + return NS_OK;
1.301 + }
1.302 +
1.303 + Element* oldScopeElement = GetScopeElement(mStyleSheet);
1.304 +
1.305 + if (mStyleSheet && aOldDocument) {
1.306 + // We're removing the link element from the document, unload the
1.307 + // stylesheet. We want to do this even if updates are disabled, since
1.308 + // otherwise a sheet with a stale linking element pointer will be hanging
1.309 + // around -- not good!
1.310 + if (aOldShadowRoot) {
1.311 + aOldShadowRoot->RemoveSheet(mStyleSheet);
1.312 + } else {
1.313 + aOldDocument->BeginUpdate(UPDATE_STYLE);
1.314 + aOldDocument->RemoveStyleSheet(mStyleSheet);
1.315 + aOldDocument->EndUpdate(UPDATE_STYLE);
1.316 + }
1.317 +
1.318 + nsStyleLinkElement::SetStyleSheet(nullptr);
1.319 + if (oldScopeElement) {
1.320 + UpdateIsElementInStyleScopeFlagOnSubtree(oldScopeElement);
1.321 + }
1.322 + }
1.323 +
1.324 + // When static documents are created, stylesheets are cloned manually.
1.325 + if (mDontLoadStyle || !mUpdatesEnabled ||
1.326 + thisContent->OwnerDoc()->IsStaticDocument()) {
1.327 + return NS_OK;
1.328 + }
1.329 +
1.330 + nsCOMPtr<nsIDocument> doc = thisContent->GetDocument();
1.331 +
1.332 + if (!doc || !doc->CSSLoader()->GetEnabled()) {
1.333 + return NS_OK;
1.334 + }
1.335 +
1.336 + bool isInline;
1.337 + nsCOMPtr<nsIURI> uri = GetStyleSheetURL(&isInline);
1.338 +
1.339 + if (!aForceUpdate && mStyleSheet && !isInline && uri) {
1.340 + nsIURI* oldURI = mStyleSheet->GetSheetURI();
1.341 + if (oldURI) {
1.342 + bool equal;
1.343 + nsresult rv = oldURI->Equals(uri, &equal);
1.344 + if (NS_SUCCEEDED(rv) && equal) {
1.345 + return NS_OK; // We already loaded this stylesheet
1.346 + }
1.347 + }
1.348 + }
1.349 +
1.350 + if (mStyleSheet) {
1.351 + if (thisContent->HasFlag(NODE_IS_IN_SHADOW_TREE)) {
1.352 + ShadowRoot* containingShadow = thisContent->GetContainingShadow();
1.353 + containingShadow->RemoveSheet(mStyleSheet);
1.354 + } else {
1.355 + doc->BeginUpdate(UPDATE_STYLE);
1.356 + doc->RemoveStyleSheet(mStyleSheet);
1.357 + doc->EndUpdate(UPDATE_STYLE);
1.358 + }
1.359 +
1.360 + nsStyleLinkElement::SetStyleSheet(nullptr);
1.361 + }
1.362 +
1.363 + if (!uri && !isInline) {
1.364 + return NS_OK; // If href is empty and this is not inline style then just bail
1.365 + }
1.366 +
1.367 + nsAutoString title, type, media;
1.368 + bool isScoped;
1.369 + bool isAlternate;
1.370 +
1.371 + GetStyleSheetInfo(title, type, media, &isScoped, &isAlternate);
1.372 +
1.373 + if (!type.LowerCaseEqualsLiteral("text/css")) {
1.374 + return NS_OK;
1.375 + }
1.376 +
1.377 + Element* scopeElement = isScoped ? thisContent->GetParentElement() : nullptr;
1.378 + if (scopeElement) {
1.379 + NS_ASSERTION(isInline, "non-inline style must not have scope element");
1.380 + SetIsElementInStyleScopeFlagOnSubtree(scopeElement);
1.381 + }
1.382 +
1.383 + bool doneLoading = false;
1.384 + nsresult rv = NS_OK;
1.385 + if (isInline) {
1.386 + nsAutoString text;
1.387 + if (!nsContentUtils::GetNodeTextContent(thisContent, false, text)) {
1.388 + return NS_ERROR_OUT_OF_MEMORY;
1.389 + }
1.390 +
1.391 + MOZ_ASSERT(thisContent->Tag() != nsGkAtoms::link,
1.392 + "<link> is not 'inline', and needs different CSP checks");
1.393 + if (!nsStyleUtil::CSPAllowsInlineStyle(thisContent,
1.394 + thisContent->NodePrincipal(),
1.395 + doc->GetDocumentURI(),
1.396 + mLineNumber, text, &rv))
1.397 + return rv;
1.398 +
1.399 + // Parse the style sheet.
1.400 + rv = doc->CSSLoader()->
1.401 + LoadInlineStyle(thisContent, text, mLineNumber, title, media,
1.402 + scopeElement, aObserver, &doneLoading, &isAlternate);
1.403 + }
1.404 + else {
1.405 + // XXXbz clone the URI here to work around content policies modifying URIs.
1.406 + nsCOMPtr<nsIURI> clonedURI;
1.407 + uri->Clone(getter_AddRefs(clonedURI));
1.408 + NS_ENSURE_TRUE(clonedURI, NS_ERROR_OUT_OF_MEMORY);
1.409 + rv = doc->CSSLoader()->
1.410 + LoadStyleLink(thisContent, clonedURI, title, media, isAlternate,
1.411 + GetCORSMode(), aObserver, &isAlternate);
1.412 + if (NS_FAILED(rv)) {
1.413 + // Don't propagate LoadStyleLink() errors further than this, since some
1.414 + // consumers (e.g. nsXMLContentSink) will completely abort on innocuous
1.415 + // things like a stylesheet load being blocked by the security system.
1.416 + doneLoading = true;
1.417 + isAlternate = false;
1.418 + rv = NS_OK;
1.419 + }
1.420 + }
1.421 +
1.422 + NS_ENSURE_SUCCESS(rv, rv);
1.423 +
1.424 + *aWillNotify = !doneLoading;
1.425 + *aIsAlternate = isAlternate;
1.426 +
1.427 + return NS_OK;
1.428 +}
1.429 +
1.430 +void
1.431 +nsStyleLinkElement::UpdateStyleSheetScopedness(bool aIsNowScoped)
1.432 +{
1.433 + if (!mStyleSheet) {
1.434 + return;
1.435 + }
1.436 +
1.437 + nsCOMPtr<nsIContent> thisContent;
1.438 + CallQueryInterface(this, getter_AddRefs(thisContent));
1.439 +
1.440 + Element* oldScopeElement = mStyleSheet->GetScopeElement();
1.441 + Element* newScopeElement = aIsNowScoped ?
1.442 + thisContent->GetParentElement() :
1.443 + nullptr;
1.444 +
1.445 + if (oldScopeElement == newScopeElement) {
1.446 + return;
1.447 + }
1.448 +
1.449 + nsIDocument* document = thisContent->GetOwnerDocument();
1.450 +
1.451 + if (thisContent->HasFlag(NODE_IS_IN_SHADOW_TREE)) {
1.452 + ShadowRoot* containingShadow = thisContent->GetContainingShadow();
1.453 + containingShadow->RemoveSheet(mStyleSheet);
1.454 +
1.455 + mStyleSheet->SetScopeElement(newScopeElement);
1.456 +
1.457 + containingShadow->InsertSheet(mStyleSheet, thisContent);
1.458 + } else {
1.459 + document->BeginUpdate(UPDATE_STYLE);
1.460 + document->RemoveStyleSheet(mStyleSheet);
1.461 +
1.462 + mStyleSheet->SetScopeElement(newScopeElement);
1.463 +
1.464 + document->AddStyleSheet(mStyleSheet);
1.465 + document->EndUpdate(UPDATE_STYLE);
1.466 + }
1.467 +
1.468 + if (oldScopeElement) {
1.469 + UpdateIsElementInStyleScopeFlagOnSubtree(oldScopeElement);
1.470 + }
1.471 + if (newScopeElement) {
1.472 + SetIsElementInStyleScopeFlagOnSubtree(newScopeElement);
1.473 + }
1.474 +}
