gecko-dev/dom/base/nsStyleLinkElement.cpp
Patrick McManus 0110ebbcda bug 1135160 - implement link rel=preconnect r=smaug
--HG--
extra : rebase_source : 445d77480f9cd6ca8ce0bfd9e6596f92d459323a
2015-02-20 17:01:36 -05:00

495 lines
14 KiB
C++

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