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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/dom/BindContext.h"
#include "mozilla/dom/HTMLMetaElement.h"
#include "mozilla/dom/HTMLMetaElementBinding.h"
#include "mozilla/dom/nsCSPService.h"
#include "mozilla/dom/nsCSPUtils.h"
#include "mozilla/dom/ViewportMetaData.h"
#include "mozilla/Logging.h"
#include "mozilla/StaticPrefs_security.h"
#include "nsContentUtils.h"
#include "nsSandboxFlags.h"
#include "nsStyleConsts.h"
#include "nsIXMLContentSink.h"
static mozilla::LazyLogModule gMetaElementLog("nsMetaElement");
#define LOG(msg) MOZ_LOG(gMetaElementLog, mozilla::LogLevel::Debug, msg)
#define LOG_ENABLED() MOZ_LOG_TEST(gMetaElementLog, mozilla::LogLevel::Debug)
NS_IMPL_NS_NEW_HTML_ELEMENT(Meta)
namespace mozilla::dom {
HTMLMetaElement::HTMLMetaElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
: nsGenericHTMLElement(std::move(aNodeInfo)) {}
HTMLMetaElement::~HTMLMetaElement() = default;
NS_IMPL_ELEMENT_CLONE(HTMLMetaElement)
void HTMLMetaElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue,
nsIPrincipal* aSubjectPrincipal,
bool aNotify) {
if (aNameSpaceID == kNameSpaceID_None) {
if (Document* document = GetUncomposedDoc()) {
if (aName == nsGkAtoms::content) {
if (const nsAttrValue* name = GetParsedAttr(nsGkAtoms::name)) {
MetaAddedOrChanged(*document, *name, ChangeKind::ContentChange);
}
CreateAndDispatchEvent(*document, u"DOMMetaChanged"_ns);
} else if (aName == nsGkAtoms::name) {
if (aOldValue) {
MetaRemoved(*document, *aOldValue, ChangeKind::NameChange);
}
if (aValue) {
MetaAddedOrChanged(*document, *aValue, ChangeKind::NameChange);
}
CreateAndDispatchEvent(*document, u"DOMMetaChanged"_ns);
}
}
}
return nsGenericHTMLElement::AfterSetAttr(
aNameSpaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
}
nsresult HTMLMetaElement::BindToTree(BindContext& aContext, nsINode& aParent) {
nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent);
NS_ENSURE_SUCCESS(rv, rv);
if (!IsInUncomposedDoc()) {
return rv;
}
Document& doc = aContext.OwnerDoc();
bool shouldProcessMeta = true;
// We don't want to call ProcessMETATag when we are pretty print
// the document
if (doc.IsXMLDocument()) {
if (nsCOMPtr<nsIXMLContentSink> xmlSink =
do_QueryInterface(doc.GetCurrentContentSink())) {
if (xmlSink->IsPrettyPrintXML() &&
xmlSink->IsPrettyPrintHasSpecialRoot()) {
shouldProcessMeta = false;
}
}
}
if (shouldProcessMeta) {
doc.ProcessMETATag(this);
}
if (AttrValueIs(kNameSpaceID_None, nsGkAtoms::httpEquiv, nsGkAtoms::headerCSP,
eIgnoreCase)) {
// only accept <meta http-equiv="Content-Security-Policy" content=""> if it
// appears in the <head> element.
Element* headElt = doc.GetHeadElement();
if (headElt && IsInclusiveDescendantOf(headElt)) {
nsAutoString content;
GetContent(content);
if (LOG_ENABLED()) {
nsAutoCString documentURIspec;
if (nsIURI* documentURI = doc.GetDocumentURI()) {
documentURI->GetAsciiSpec(documentURIspec);
}
LOG(
("HTMLMetaElement %p sets CSP '%s' on document=%p, "
"document-uri=%s",
this, NS_ConvertUTF16toUTF8(content).get(), &doc,
documentURIspec.get()));
}
CSP_ApplyMetaCSPToDoc(doc, content);
}
}
if (const nsAttrValue* name = GetParsedAttr(nsGkAtoms::name)) {
MetaAddedOrChanged(doc, *name, ChangeKind::TreeChange);
}
CreateAndDispatchEvent(doc, u"DOMMetaAdded"_ns);
return rv;
}
void HTMLMetaElement::UnbindFromTree(UnbindContext& aContext) {
if (Document* oldDoc = GetUncomposedDoc()) {
if (const nsAttrValue* name = GetParsedAttr(nsGkAtoms::name)) {
MetaRemoved(*oldDoc, *name, ChangeKind::TreeChange);
}
CreateAndDispatchEvent(*oldDoc, u"DOMMetaRemoved"_ns);
}
nsGenericHTMLElement::UnbindFromTree(aContext);
}
void HTMLMetaElement::CreateAndDispatchEvent(Document&,
const nsAString& aEventName) {
AsyncEventDispatcher::RunDOMEventWhenSafe(*this, aEventName, CanBubble::eYes,
ChromeOnlyDispatch::eYes);
}
JSObject* HTMLMetaElement::WrapNode(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return HTMLMetaElement_Binding::Wrap(aCx, this, aGivenProto);
}
void HTMLMetaElement::MetaAddedOrChanged(Document& aDoc,
const nsAttrValue& aName,
ChangeKind aChangeKind) {
nsAutoString content;
const bool hasContent = GetAttr(nsGkAtoms::content, content);
if (aName.Equals(nsGkAtoms::viewport, eIgnoreCase)) {
if (hasContent) {
aDoc.SetMetaViewportData(MakeUnique<ViewportMetaData>(content));
}
return;
}
if (aName.Equals(nsGkAtoms::referrer, eIgnoreCase)) {
content = nsContentUtils::TrimWhitespace<nsContentUtils::IsHTMLWhitespace>(
content);
return aDoc.UpdateReferrerInfoFromMeta(content,
/* aPreload = */ false);
}
if (aName.Equals(nsGkAtoms::color_scheme, eIgnoreCase)) {
if (aChangeKind != ChangeKind::ContentChange) {
return aDoc.AddColorSchemeMeta(*this);
}
return aDoc.RecomputeColorScheme();
}
}
void HTMLMetaElement::MetaRemoved(Document& aDoc, const nsAttrValue& aName,
ChangeKind aChangeKind) {
MOZ_ASSERT(aChangeKind != ChangeKind::ContentChange,
"Content change can't trigger removal");
if (aName.Equals(nsGkAtoms::color_scheme, eIgnoreCase)) {
return aDoc.RemoveColorSchemeMeta(*this);
}
}
} // namespace mozilla::dom