michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  *
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * A base class which implements nsIStyleSheetLinkingElement and can
michael@0:  * be subclassed by various content nodes that want to load
michael@0:  * stylesheets (<style>, <link>, processing instructions, etc).
michael@0:  */
michael@0: 
michael@0: #include "nsStyleLinkElement.h"
michael@0: 
michael@0: #include "mozilla/css/Loader.h"
michael@0: #include "mozilla/dom/Element.h"
michael@0: #include "mozilla/dom/ShadowRoot.h"
michael@0: #include "nsCSSStyleSheet.h"
michael@0: #include "nsIContent.h"
michael@0: #include "nsIDocument.h"
michael@0: #include "nsIDOMComment.h"
michael@0: #include "nsIDOMNode.h"
michael@0: #include "nsIDOMStyleSheet.h"
michael@0: #include "nsNetUtil.h"
michael@0: #include "nsUnicharUtils.h"
michael@0: #include "nsCRT.h"
michael@0: #include "nsXPCOMCIDInternal.h"
michael@0: #include "nsUnicharInputStream.h"
michael@0: #include "nsContentUtils.h"
michael@0: #include "nsStyleUtil.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: using namespace mozilla::dom;
michael@0: 
michael@0: nsStyleLinkElement::nsStyleLinkElement()
michael@0:   : mDontLoadStyle(false)
michael@0:   , mUpdatesEnabled(true)
michael@0:   , mLineNumber(1)
michael@0: {
michael@0: }
michael@0: 
michael@0: nsStyleLinkElement::~nsStyleLinkElement()
michael@0: {
michael@0:   nsStyleLinkElement::SetStyleSheet(nullptr);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsStyleLinkElement::Unlink()
michael@0: {
michael@0:   mStyleSheet = nullptr;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsStyleLinkElement::Traverse(nsCycleCollectionTraversalCallback &cb)
michael@0: {
michael@0:   nsStyleLinkElement* tmp = this;
michael@0:   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStyleSheet);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP 
michael@0: nsStyleLinkElement::SetStyleSheet(nsCSSStyleSheet* aStyleSheet)
michael@0: {
michael@0:   if (mStyleSheet) {
michael@0:     mStyleSheet->SetOwningNode(nullptr);
michael@0:   }
michael@0: 
michael@0:   mStyleSheet = aStyleSheet;
michael@0:   if (mStyleSheet) {
michael@0:     nsCOMPtr<nsINode> node = do_QueryObject(this);
michael@0:     if (node) {
michael@0:       mStyleSheet->SetOwningNode(node);
michael@0:     }
michael@0:   }
michael@0:     
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP 
michael@0: nsStyleLinkElement::GetStyleSheet(nsIStyleSheet*& aStyleSheet)
michael@0: {
michael@0:   aStyleSheet = mStyleSheet;
michael@0:   NS_IF_ADDREF(aStyleSheet);
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP 
michael@0: nsStyleLinkElement::InitStyleLinkElement(bool aDontLoadStyle)
michael@0: {
michael@0:   mDontLoadStyle = aDontLoadStyle;
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsStyleLinkElement::SetEnableUpdates(bool aEnableUpdates)
michael@0: {
michael@0:   mUpdatesEnabled = aEnableUpdates;
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsStyleLinkElement::GetCharset(nsAString& aCharset)
michael@0: {
michael@0:   // descendants have to implement this themselves
michael@0:   return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }
michael@0: 
michael@0: /* virtual */ void
michael@0: nsStyleLinkElement::OverrideBaseURI(nsIURI* aNewBaseURI)
michael@0: {
michael@0:   NS_NOTREACHED("Base URI can't be overriden in this implementation "
michael@0:                 "of nsIStyleSheetLinkingElement.");
michael@0: }
michael@0: 
michael@0: /* virtual */ void
michael@0: nsStyleLinkElement::SetLineNumber(uint32_t aLineNumber)
michael@0: {
michael@0:   mLineNumber = aLineNumber;
michael@0: }
michael@0: 
michael@0: static uint32_t ToLinkMask(const nsAString& aLink)
michael@0: { 
michael@0:   if (aLink.EqualsLiteral("prefetch"))
michael@0:     return nsStyleLinkElement::ePREFETCH;
michael@0:   else if (aLink.EqualsLiteral("dns-prefetch"))
michael@0:     return nsStyleLinkElement::eDNS_PREFETCH;
michael@0:   else if (aLink.EqualsLiteral("stylesheet"))
michael@0:     return nsStyleLinkElement::eSTYLESHEET;
michael@0:   else if (aLink.EqualsLiteral("next"))
michael@0:     return nsStyleLinkElement::eNEXT;
michael@0:   else if (aLink.EqualsLiteral("alternate"))
michael@0:     return nsStyleLinkElement::eALTERNATE;
michael@0:   else 
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: uint32_t nsStyleLinkElement::ParseLinkTypes(const nsAString& aTypes)
michael@0: {
michael@0:   uint32_t linkMask = 0;
michael@0:   nsAString::const_iterator start, done;
michael@0:   aTypes.BeginReading(start);
michael@0:   aTypes.EndReading(done);
michael@0:   if (start == done)
michael@0:     return linkMask;
michael@0: 
michael@0:   nsAString::const_iterator current(start);
michael@0:   bool inString = !nsContentUtils::IsHTMLWhitespace(*current);
michael@0:   nsAutoString subString;
michael@0:   
michael@0:   while (current != done) {
michael@0:     if (nsContentUtils::IsHTMLWhitespace(*current)) {
michael@0:       if (inString) {
michael@0:         nsContentUtils::ASCIIToLower(Substring(start, current), subString);
michael@0:         linkMask |= ToLinkMask(subString);
michael@0:         inString = false;
michael@0:       }
michael@0:     }
michael@0:     else {
michael@0:       if (!inString) {
michael@0:         start = current;
michael@0:         inString = true;
michael@0:       }
michael@0:     }
michael@0:     ++current;
michael@0:   }
michael@0:   if (inString) {
michael@0:     nsContentUtils::ASCIIToLower(Substring(start, current), subString);
michael@0:     linkMask |= ToLinkMask(subString);
michael@0:   }
michael@0:   return linkMask;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsStyleLinkElement::UpdateStyleSheet(nsICSSLoaderObserver* aObserver,
michael@0:                                      bool* aWillNotify,
michael@0:                                      bool* aIsAlternate)
michael@0: {
michael@0:   return DoUpdateStyleSheet(nullptr, nullptr, aObserver, aWillNotify,
michael@0:                             aIsAlternate, false);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsStyleLinkElement::UpdateStyleSheetInternal(nsIDocument *aOldDocument,
michael@0:                                              ShadowRoot *aOldShadowRoot,
michael@0:                                              bool aForceUpdate)
michael@0: {
michael@0:   bool notify, alternate;
michael@0:   return DoUpdateStyleSheet(aOldDocument, aOldShadowRoot, nullptr, &notify,
michael@0:                             &alternate, aForceUpdate);
michael@0: }
michael@0: 
michael@0: static bool
michael@0: IsScopedStyleElement(nsIContent* aContent)
michael@0: {
michael@0:   // This is quicker than, say, QIing aContent to nsStyleLinkElement
michael@0:   // and then calling its virtual GetStyleSheetInfo method to find out
michael@0:   // if it is scoped.
michael@0:   return (aContent->IsHTML(nsGkAtoms::style) ||
michael@0:           aContent->IsSVG(nsGkAtoms::style)) &&
michael@0:          aContent->HasAttr(kNameSpaceID_None, nsGkAtoms::scoped);
michael@0: }
michael@0: 
michael@0: static void
michael@0: SetIsElementInStyleScopeFlagOnSubtree(Element* aElement)
michael@0: {
michael@0:   if (aElement->IsElementInStyleScope()) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   aElement->SetIsElementInStyleScope();
michael@0: 
michael@0:   nsIContent* n = aElement->GetNextNode(aElement);
michael@0:   while (n) {
michael@0:     if (n->IsElementInStyleScope()) {
michael@0:       n = n->GetNextNonChildNode(aElement);
michael@0:     } else {
michael@0:       if (n->IsElement()) {
michael@0:         n->SetIsElementInStyleScope();
michael@0:       }
michael@0:       n = n->GetNextNode(aElement);
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: static bool
michael@0: HasScopedStyleSheetChild(nsIContent* aContent)
michael@0: {
michael@0:   for (nsIContent* n = aContent->GetFirstChild(); n; n = n->GetNextSibling()) {
michael@0:     if (IsScopedStyleElement(n)) {
michael@0:       return true;
michael@0:     }
michael@0:   }
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: // Called when aElement has had a <style scoped> child removed.
michael@0: static void
michael@0: UpdateIsElementInStyleScopeFlagOnSubtree(Element* aElement)
michael@0: {
michael@0:   NS_ASSERTION(aElement->IsElementInStyleScope(),
michael@0:                "only call UpdateIsElementInStyleScopeFlagOnSubtree on a "
michael@0:                "subtree that has IsElementInStyleScope boolean flag set");
michael@0: 
michael@0:   if (HasScopedStyleSheetChild(aElement)) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   aElement->ClearIsElementInStyleScope();
michael@0: 
michael@0:   nsIContent* n = aElement->GetNextNode(aElement);
michael@0:   while (n) {
michael@0:     if (HasScopedStyleSheetChild(n)) {
michael@0:       n = n->GetNextNonChildNode(aElement);
michael@0:     } else {
michael@0:       if (n->IsElement()) {
michael@0:         n->ClearIsElementInStyleScope();
michael@0:       }
michael@0:       n = n->GetNextNode(aElement);
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: static Element*
michael@0: GetScopeElement(nsIStyleSheet* aSheet)
michael@0: {
michael@0:   nsRefPtr<nsCSSStyleSheet> cssStyleSheet = do_QueryObject(aSheet);
michael@0:   if (!cssStyleSheet) {
michael@0:     return nullptr;
michael@0:   }
michael@0: 
michael@0:   return cssStyleSheet->GetScopeElement();
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsStyleLinkElement::DoUpdateStyleSheet(nsIDocument* aOldDocument,
michael@0:                                        ShadowRoot* aOldShadowRoot,
michael@0:                                        nsICSSLoaderObserver* aObserver,
michael@0:                                        bool* aWillNotify,
michael@0:                                        bool* aIsAlternate,
michael@0:                                        bool aForceUpdate)
michael@0: {
michael@0:   *aWillNotify = false;
michael@0: 
michael@0:   nsCOMPtr<nsIContent> thisContent;
michael@0:   CallQueryInterface(this, getter_AddRefs(thisContent));
michael@0: 
michael@0:   // All instances of nsStyleLinkElement should implement nsIContent.
michael@0:   NS_ENSURE_TRUE(thisContent, NS_ERROR_FAILURE);
michael@0: 
michael@0:   // Check for a ShadowRoot because link elements are inert in a
michael@0:   // ShadowRoot.
michael@0:   ShadowRoot* containingShadow = thisContent->GetContainingShadow();
michael@0:   if (thisContent->IsHTML(nsGkAtoms::link) &&
michael@0:       (aOldShadowRoot || containingShadow)) {
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   Element* oldScopeElement = GetScopeElement(mStyleSheet);
michael@0: 
michael@0:   if (mStyleSheet && aOldDocument) {
michael@0:     // We're removing the link element from the document, unload the
michael@0:     // stylesheet.  We want to do this even if updates are disabled, since
michael@0:     // otherwise a sheet with a stale linking element pointer will be hanging
michael@0:     // around -- not good!
michael@0:     if (aOldShadowRoot) {
michael@0:       aOldShadowRoot->RemoveSheet(mStyleSheet);
michael@0:     } else {
michael@0:       aOldDocument->BeginUpdate(UPDATE_STYLE);
michael@0:       aOldDocument->RemoveStyleSheet(mStyleSheet);
michael@0:       aOldDocument->EndUpdate(UPDATE_STYLE);
michael@0:     }
michael@0: 
michael@0:     nsStyleLinkElement::SetStyleSheet(nullptr);
michael@0:     if (oldScopeElement) {
michael@0:       UpdateIsElementInStyleScopeFlagOnSubtree(oldScopeElement);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // When static documents are created, stylesheets are cloned manually.
michael@0:   if (mDontLoadStyle || !mUpdatesEnabled ||
michael@0:       thisContent->OwnerDoc()->IsStaticDocument()) {
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   nsCOMPtr<nsIDocument> doc = thisContent->GetDocument();
michael@0: 
michael@0:   if (!doc || !doc->CSSLoader()->GetEnabled()) {
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   bool isInline;
michael@0:   nsCOMPtr<nsIURI> uri = GetStyleSheetURL(&isInline);
michael@0: 
michael@0:   if (!aForceUpdate && mStyleSheet && !isInline && uri) {
michael@0:     nsIURI* oldURI = mStyleSheet->GetSheetURI();
michael@0:     if (oldURI) {
michael@0:       bool equal;
michael@0:       nsresult rv = oldURI->Equals(uri, &equal);
michael@0:       if (NS_SUCCEEDED(rv) && equal) {
michael@0:         return NS_OK; // We already loaded this stylesheet
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   if (mStyleSheet) {
michael@0:     if (thisContent->HasFlag(NODE_IS_IN_SHADOW_TREE)) {
michael@0:       ShadowRoot* containingShadow = thisContent->GetContainingShadow();
michael@0:       containingShadow->RemoveSheet(mStyleSheet);
michael@0:     } else {
michael@0:       doc->BeginUpdate(UPDATE_STYLE);
michael@0:       doc->RemoveStyleSheet(mStyleSheet);
michael@0:       doc->EndUpdate(UPDATE_STYLE);
michael@0:     }
michael@0: 
michael@0:     nsStyleLinkElement::SetStyleSheet(nullptr);
michael@0:   }
michael@0: 
michael@0:   if (!uri && !isInline) {
michael@0:     return NS_OK; // If href is empty and this is not inline style then just bail
michael@0:   }
michael@0: 
michael@0:   nsAutoString title, type, media;
michael@0:   bool isScoped;
michael@0:   bool isAlternate;
michael@0: 
michael@0:   GetStyleSheetInfo(title, type, media, &isScoped, &isAlternate);
michael@0: 
michael@0:   if (!type.LowerCaseEqualsLiteral("text/css")) {
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   Element* scopeElement = isScoped ? thisContent->GetParentElement() : nullptr;
michael@0:   if (scopeElement) {
michael@0:     NS_ASSERTION(isInline, "non-inline style must not have scope element");
michael@0:     SetIsElementInStyleScopeFlagOnSubtree(scopeElement);
michael@0:   }
michael@0: 
michael@0:   bool doneLoading = false;
michael@0:   nsresult rv = NS_OK;
michael@0:   if (isInline) {
michael@0:     nsAutoString text;
michael@0:     if (!nsContentUtils::GetNodeTextContent(thisContent, false, text)) {
michael@0:       return NS_ERROR_OUT_OF_MEMORY;
michael@0:     }
michael@0: 
michael@0:     MOZ_ASSERT(thisContent->Tag() != nsGkAtoms::link,
michael@0:                "<link> is not 'inline', and needs different CSP checks");
michael@0:     if (!nsStyleUtil::CSPAllowsInlineStyle(thisContent,
michael@0:                                            thisContent->NodePrincipal(),
michael@0:                                            doc->GetDocumentURI(),
michael@0:                                            mLineNumber, text, &rv))
michael@0:       return rv;
michael@0: 
michael@0:     // Parse the style sheet.
michael@0:     rv = doc->CSSLoader()->
michael@0:       LoadInlineStyle(thisContent, text, mLineNumber, title, media,
michael@0:                       scopeElement, aObserver, &doneLoading, &isAlternate);
michael@0:   }
michael@0:   else {
michael@0:     // XXXbz clone the URI here to work around content policies modifying URIs.
michael@0:     nsCOMPtr<nsIURI> clonedURI;
michael@0:     uri->Clone(getter_AddRefs(clonedURI));
michael@0:     NS_ENSURE_TRUE(clonedURI, NS_ERROR_OUT_OF_MEMORY);
michael@0:     rv = doc->CSSLoader()->
michael@0:       LoadStyleLink(thisContent, clonedURI, title, media, isAlternate,
michael@0:                     GetCORSMode(), aObserver, &isAlternate);
michael@0:     if (NS_FAILED(rv)) {
michael@0:       // Don't propagate LoadStyleLink() errors further than this, since some
michael@0:       // consumers (e.g. nsXMLContentSink) will completely abort on innocuous
michael@0:       // things like a stylesheet load being blocked by the security system.
michael@0:       doneLoading = true;
michael@0:       isAlternate = false;
michael@0:       rv = NS_OK;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   NS_ENSURE_SUCCESS(rv, rv);
michael@0: 
michael@0:   *aWillNotify = !doneLoading;
michael@0:   *aIsAlternate = isAlternate;
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsStyleLinkElement::UpdateStyleSheetScopedness(bool aIsNowScoped)
michael@0: {
michael@0:   if (!mStyleSheet) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   nsCOMPtr<nsIContent> thisContent;
michael@0:   CallQueryInterface(this, getter_AddRefs(thisContent));
michael@0: 
michael@0:   Element* oldScopeElement = mStyleSheet->GetScopeElement();
michael@0:   Element* newScopeElement = aIsNowScoped ?
michael@0:                                thisContent->GetParentElement() :
michael@0:                                nullptr;
michael@0: 
michael@0:   if (oldScopeElement == newScopeElement) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   nsIDocument* document = thisContent->GetOwnerDocument();
michael@0: 
michael@0:   if (thisContent->HasFlag(NODE_IS_IN_SHADOW_TREE)) {
michael@0:     ShadowRoot* containingShadow = thisContent->GetContainingShadow();
michael@0:     containingShadow->RemoveSheet(mStyleSheet);
michael@0: 
michael@0:     mStyleSheet->SetScopeElement(newScopeElement);
michael@0: 
michael@0:     containingShadow->InsertSheet(mStyleSheet, thisContent);
michael@0:   } else {
michael@0:     document->BeginUpdate(UPDATE_STYLE);
michael@0:     document->RemoveStyleSheet(mStyleSheet);
michael@0: 
michael@0:     mStyleSheet->SetScopeElement(newScopeElement);
michael@0: 
michael@0:     document->AddStyleSheet(mStyleSheet);
michael@0:     document->EndUpdate(UPDATE_STYLE);
michael@0:   }
michael@0: 
michael@0:   if (oldScopeElement) {
michael@0:     UpdateIsElementInStyleScopeFlagOnSubtree(oldScopeElement);
michael@0:   }
michael@0:   if (newScopeElement) {
michael@0:     SetIsElementInStyleScopeFlagOnSubtree(newScopeElement);
michael@0:   }
michael@0: }