Files
tubestation/dom/html/HTMLMetaElement.cpp
Kirk Steuber e2ea33731f Bug 1363481 - Add the old attribute value as a parameter to Element::AfterSetAttr r=bz
In order to facilitate the movement of code with side-effects called by Element::SetAttr to Element::BeforeSetAttr and Element::AfterSetAttr, Element::AfterSetAttr should have access to the old value of the attribute. This includes information about whether there was previously a value set or not.

Accomplishing this involved passing an additional argument through functions that find and change the old attribute value in order to ensure that we can differentiate between an empty old value and an absent old value (attribute was not set).

Note that while I tried to ensure that accurate values (and their absence) are reported to Element::AfterSetAttr, I largely ignored SVG. While the old value reported for SVG values should be however accurate the value already being reported to SetAttrAndNotify was, SVG elements do not currently report unset values properly because they will never pass a null pointer to SetAttrAndNotify.

MozReview-Commit-ID: K1mha8CNFZP
2017-05-18 14:09:01 -07:00

174 lines
5.8 KiB
C++

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/dom/HTMLMetaElement.h"
#include "mozilla/dom/HTMLMetaElementBinding.h"
#include "mozilla/dom/nsCSPService.h"
#include "nsContentUtils.h"
#include "nsStyleConsts.h"
#include "nsIContentSecurityPolicy.h"
NS_IMPL_NS_NEW_HTML_ELEMENT(Meta)
namespace mozilla {
namespace dom {
HTMLMetaElement::HTMLMetaElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
: nsGenericHTMLElement(aNodeInfo)
{
}
HTMLMetaElement::~HTMLMetaElement()
{
}
NS_IMPL_ISUPPORTS_INHERITED(HTMLMetaElement, nsGenericHTMLElement,
nsIDOMHTMLMetaElement)
NS_IMPL_ELEMENT_CLONE(HTMLMetaElement)
NS_IMPL_STRING_ATTR(HTMLMetaElement, Content, content)
NS_IMPL_STRING_ATTR(HTMLMetaElement, HttpEquiv, httpEquiv)
NS_IMPL_STRING_ATTR(HTMLMetaElement, Name, name)
NS_IMPL_STRING_ATTR(HTMLMetaElement, Scheme, scheme)
nsresult
HTMLMetaElement::SetMetaReferrer(nsIDocument* aDocument)
{
if (!aDocument ||
!AttrValueIs(kNameSpaceID_None, nsGkAtoms::name, nsGkAtoms::referrer, eIgnoreCase)) {
return NS_OK;
}
nsAutoString content;
nsresult rv = GetContent(content);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
Element* headElt = aDocument->GetHeadElement();
if (headElt && nsContentUtils::ContentIsDescendantOf(this, headElt)) {
content = nsContentUtils::TrimWhitespace<nsContentUtils::IsHTMLWhitespace>(content);
aDocument->SetHeaderData(nsGkAtoms::referrer, content);
}
return NS_OK;
}
nsresult
HTMLMetaElement::AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue, bool aNotify)
{
if (aNameSpaceID == kNameSpaceID_None) {
nsIDocument *document = GetUncomposedDoc();
if (aName == nsGkAtoms::content) {
if (document && AttrValueIs(kNameSpaceID_None, nsGkAtoms::name,
nsGkAtoms::viewport, eIgnoreCase)) {
nsAutoString content;
nsresult rv = GetContent(content);
NS_ENSURE_SUCCESS(rv, rv);
nsContentUtils::ProcessViewportInfo(document, content);
}
CreateAndDispatchEvent(document, NS_LITERAL_STRING("DOMMetaChanged"));
}
// Update referrer policy when it got changed from JS
nsresult rv = SetMetaReferrer(document);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
}
return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
aOldValue, aNotify);
}
nsresult
HTMLMetaElement::BindToTree(nsIDocument* aDocument, nsIContent* aParent,
nsIContent* aBindingParent,
bool aCompileEventHandlers)
{
nsresult rv = nsGenericHTMLElement::BindToTree(aDocument, aParent,
aBindingParent,
aCompileEventHandlers);
NS_ENSURE_SUCCESS(rv, rv);
if (aDocument &&
AttrValueIs(kNameSpaceID_None, nsGkAtoms::name, nsGkAtoms::viewport, eIgnoreCase)) {
nsAutoString content;
rv = GetContent(content);
NS_ENSURE_SUCCESS(rv, rv);
nsContentUtils::ProcessViewportInfo(aDocument, content);
}
if (CSPService::sCSPEnabled && aDocument &&
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 = aDocument->GetHeadElement();
if (headElt && nsContentUtils::ContentIsDescendantOf(this, headElt)) {
nsAutoString content;
rv = GetContent(content);
NS_ENSURE_SUCCESS(rv, rv);
content = nsContentUtils::TrimWhitespace<nsContentUtils::IsHTMLWhitespace>(content);
nsIPrincipal* principal = aDocument->NodePrincipal();
nsCOMPtr<nsIContentSecurityPolicy> csp;
nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(aDocument);
principal->EnsureCSP(domDoc, getter_AddRefs(csp));
if (csp) {
// Multiple CSPs (delivered through either header of meta tag) need to be
// joined together, see:
// https://w3c.github.io/webappsec/specs/content-security-policy/#delivery-html-meta-element
rv = csp->AppendPolicy(content,
false, // csp via meta tag can not be report only
true); // delivered through the meta tag
NS_ENSURE_SUCCESS(rv, rv);
aDocument->ApplySettingsFromCSP(false);
}
}
}
// Referrer Policy spec requires a <meta name="referrer" tag to be in the
// <head> element.
rv = SetMetaReferrer(aDocument);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
CreateAndDispatchEvent(aDocument, NS_LITERAL_STRING("DOMMetaAdded"));
return rv;
}
void
HTMLMetaElement::UnbindFromTree(bool aDeep, bool aNullParent)
{
nsCOMPtr<nsIDocument> oldDoc = GetUncomposedDoc();
CreateAndDispatchEvent(oldDoc, NS_LITERAL_STRING("DOMMetaRemoved"));
nsGenericHTMLElement::UnbindFromTree(aDeep, aNullParent);
}
void
HTMLMetaElement::CreateAndDispatchEvent(nsIDocument* aDoc,
const nsAString& aEventName)
{
if (!aDoc)
return;
RefPtr<AsyncEventDispatcher> asyncDispatcher =
new AsyncEventDispatcher(this, aEventName, true, true);
asyncDispatcher->RunDOMEventWhenSafe();
}
JSObject*
HTMLMetaElement::WrapNode(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
return HTMLMetaElementBinding::Wrap(aCx, this, aGivenProto);
}
} // namespace dom
} // namespace mozilla