Quelle nsHtml5TreeBuilderCppSupplement.h
Sprache: C
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=2 sw=2 et tw=78: */ /* 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/. */
// Since `typeString` after trimming and lowercasing is only checked // for "module" and " importmap", we don't need to remember // pre-trimming emptiness here.
// intendedParent == nullptr is a special case where the // intended parent is the document.
nsNodeInfoManager* nodeInfoManager =
intendedParent ? intendedParent->OwnerDoc()->NodeInfoManager()
: mBuilder->GetNodeInfoManager();
// For microtask semantics, we need to queue either // `opRunScriptThatMayDocumentWriteOrBlock` or // `opRunScriptThatCannotDocumentWriteOrBlock` for every script // element--even ones that we already know won't run. // `mCurrentHtmlScriptCannotDocumentWriteOrBlock` controls which // kind of operation is used for an HTML script, and this is the // place where `mCurrentHtmlScriptCannotDocumentWriteOrBlock` // needs to be set correctly. // // Non-async, non-defer classic scripts that will run MUST use // `opRunScriptThatMayDocumentWriteOrBlock` in order to run // the more complex code that // 1. is able to resume the HTML parse after a parser-blocking // scripts no longer blocks the parser // 2. is able to receive more content to parse on the main thread // via document.write // 3. is able to throw away off-the-main-thread parsing results // if what's document.written on the main thread invalidates // the speculation. // // Async and defer classic scripts as well as module scripts and // importmaps MUST use `opRunScriptThatCannotDocumentWriteOrBlock`. // This is necessary particularly because the relevant main-thread // code assumes it doesn't need to deal with resuming the HTML // parse some time afterwards, so using a tree operation with // mismatching expectations regarding that responsibility may // cause the HTML parse to stall. // // Various scripts that won't actually run work with either type // of tree op in the sense that the HTML parse won't stall. // However, in the case where a script cannot block or insert // data to the HTML parser via document.write, unnecessary use // of `opRunScriptThatMayDocumentWriteOrBlock` instead of // `opRunScriptThatCannotDocumentWriteOrBlock` causes the HTML // parser to enter the speculative mode when doing so isn't // actually required. // // Ideally, we would check for `type`/`language` attribute // combinations that are known to cause non-execution as well as // ScriptLoader::IsScriptEventHandler equivalent. That way, we // wouldn't unnecessarily speculate after scripts that won't // execute. https://bugzilla.mozilla.org/show_bug.cgi?id=1848311
if (importmap) { // If we see an importmap, we don't want to later start speculative // loads for modulepreloads, since such load might finish before // the importmap is created. This also applies to module scripts so // that any modulepreload integrity checks can be performed before // the modules scripts are loaded. // This state is not part of speculation rollback: If an importmap // is seen speculatively and the speculation is rolled back, the // importmap is still considered seen. // TODO: Sync importmap seenness between the main thread and the // parser thread. // https://bugzilla.mozilla.org/show_bug.cgi?id=1848312
mHasSeenImportMap = true;
}
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_SRC); if (url) {
async = aAttributes->contains(nsHtml5AttributeName::ATTR_ASYNC);
defer = aAttributes->contains(nsHtml5AttributeName::ATTR_DEFER); if ((isModule && !mHasSeenImportMap) ||
(!isModule && !importmap && !nomodule)) {
nsHtml5String charset =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CHARSET);
nsHtml5String crossOrigin =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CROSSORIGIN);
nsHtml5String nonce =
aAttributes->getValue(nsHtml5AttributeName::ATTR_NONCE);
nsHtml5String fetchPriority = aAttributes->getValue(
nsHtml5AttributeName::ATTR_FETCHPRIORITY);
nsHtml5String integrity =
aAttributes->getValue(nsHtml5AttributeName::ATTR_INTEGRITY);
nsHtml5String referrerPolicy = aAttributes->getValue(
nsHtml5AttributeName::ATTR_REFERRERPOLICY);
mSpeculativeLoadQueue.AppendElement()->InitScript(
url, charset, type, crossOrigin, /* aMedia = */ nullptr,
nonce, fetchPriority, integrity, referrerPolicy,
mode == nsHtml5TreeBuilder::IN_HEAD, async, defer, false);
}
} // `mCurrentHtmlScriptCannotDocumentWriteOrBlock` MUST be computed to // match the ScriptLoader-perceived kind of the script regardless of // enqueuing a speculative load. Scripts with the `nomodule` attribute // never block or document.write: Either the attribute prevents a // classic script execution or is ignored on a module script or // importmap.
mCurrentHtmlScriptCannotDocumentWriteOrBlock =
isModule || importmap || async || defer || nomodule;
} elseif (nsGkAtoms::link == aName) {
nsHtml5String rel =
aAttributes->getValue(nsHtml5AttributeName::ATTR_REL); // Not splitting on space here is bogus but the old parser didn't even // do a case-insensitive check. if (rel) { if (rel.LowerCaseEqualsASCII("stylesheet")) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (url) {
nsHtml5String charset =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CHARSET);
nsHtml5String crossOrigin = aAttributes->getValue(
nsHtml5AttributeName::ATTR_CROSSORIGIN);
nsHtml5String nonce =
aAttributes->getValue(nsHtml5AttributeName::ATTR_NONCE);
nsHtml5String integrity =
aAttributes->getValue(nsHtml5AttributeName::ATTR_INTEGRITY);
nsHtml5String referrerPolicy = aAttributes->getValue(
nsHtml5AttributeName::ATTR_REFERRERPOLICY);
nsHtml5String media =
aAttributes->getValue(nsHtml5AttributeName::ATTR_MEDIA);
nsHtml5String fetchPriority = aAttributes->getValue(
nsHtml5AttributeName::ATTR_FETCHPRIORITY);
mSpeculativeLoadQueue.AppendElement()->InitStyle(
url, charset, crossOrigin, media, referrerPolicy, nonce,
integrity, false, fetchPriority);
}
} elseif (rel.LowerCaseEqualsASCII("preconnect")) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (url) {
nsHtml5String crossOrigin = aAttributes->getValue(
nsHtml5AttributeName::ATTR_CROSSORIGIN);
mSpeculativeLoadQueue.AppendElement()->InitPreconnect(
url, crossOrigin);
}
} elseif (rel.LowerCaseEqualsASCII("preload")) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (url) {
nsHtml5String as =
aAttributes->getValue(nsHtml5AttributeName::ATTR_AS);
nsHtml5String charset =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CHARSET);
nsHtml5String crossOrigin = aAttributes->getValue(
nsHtml5AttributeName::ATTR_CROSSORIGIN);
nsHtml5String nonce =
aAttributes->getValue(nsHtml5AttributeName::ATTR_NONCE);
nsHtml5String integrity =
aAttributes->getValue(nsHtml5AttributeName::ATTR_INTEGRITY);
nsHtml5String referrerPolicy = aAttributes->getValue(
nsHtml5AttributeName::ATTR_REFERRERPOLICY);
nsHtml5String media =
aAttributes->getValue(nsHtml5AttributeName::ATTR_MEDIA);
nsHtml5String fetchPriority = aAttributes->getValue(
nsHtml5AttributeName::ATTR_FETCHPRIORITY);
// Note that respective speculative loaders for scripts and // styles check all additional attributes to be equal to use the // speculative load. So, if any of them is specified and the // preload has to take the expected effect, those attributes // must also be specified on the actual tag to use the preload. // Omitting an attribute on both will make the values equal // (empty) and thus use the preload. if (as.LowerCaseEqualsASCII("script")) {
nsHtml5String type =
aAttributes->getValue(nsHtml5AttributeName::ATTR_TYPE);
mSpeculativeLoadQueue.AppendElement()->InitScript(
url, charset, type, crossOrigin, media, nonce, /* aFetchPriority */ fetchPriority, integrity,
referrerPolicy, mode == nsHtml5TreeBuilder::IN_HEAD, false, false, true);
} elseif (as.LowerCaseEqualsASCII("style")) {
mSpeculativeLoadQueue.AppendElement()->InitStyle(
url, charset, crossOrigin, media, referrerPolicy, nonce,
integrity, true, fetchPriority);
} elseif (as.LowerCaseEqualsASCII("image")) {
nsHtml5String srcset = aAttributes->getValue(
nsHtml5AttributeName::ATTR_IMAGESRCSET);
nsHtml5String sizes = aAttributes->getValue(
nsHtml5AttributeName::ATTR_IMAGESIZES);
mSpeculativeLoadQueue.AppendElement()->InitImage(
url, crossOrigin, media, referrerPolicy, srcset, sizes, true, fetchPriority);
} elseif (as.LowerCaseEqualsASCII("font")) {
mSpeculativeLoadQueue.AppendElement()->InitFont(
url, crossOrigin, media, referrerPolicy, fetchPriority);
} elseif (as.LowerCaseEqualsASCII("fetch")) {
mSpeculativeLoadQueue.AppendElement()->InitFetch(
url, crossOrigin, media, referrerPolicy, fetchPriority);
} // Other "as" values will be supported later.
}
} elseif (mozilla::StaticPrefs::network_modulepreload() &&
rel.LowerCaseEqualsASCII("modulepreload") &&
!mHasSeenImportMap) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (url && url.Length() != 0) {
nsHtml5String as =
aAttributes->getValue(nsHtml5AttributeName::ATTR_AS);
nsAutoString asString;
as.ToString(asString); if (mozilla::net::IsScriptLikeOrInvalid(asString)) {
nsHtml5String charset =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CHARSET);
RefPtr<nsAtom> moduleType = nsGkAtoms::_module;
nsHtml5String type =
nsHtml5String::FromAtom(moduleType.forget());
nsHtml5String crossOrigin = aAttributes->getValue(
nsHtml5AttributeName::ATTR_CROSSORIGIN);
nsHtml5String media =
aAttributes->getValue(nsHtml5AttributeName::ATTR_MEDIA);
nsHtml5String nonce =
aAttributes->getValue(nsHtml5AttributeName::ATTR_NONCE);
nsHtml5String integrity = aAttributes->getValue(
nsHtml5AttributeName::ATTR_INTEGRITY);
nsHtml5String referrerPolicy = aAttributes->getValue(
nsHtml5AttributeName::ATTR_REFERRERPOLICY);
nsHtml5String fetchPriority = aAttributes->getValue(
nsHtml5AttributeName::ATTR_FETCHPRIORITY);
mSpeculativeLoadQueue.AppendElement()->InitScript(
url, charset, type, crossOrigin, media, nonce, /* aFetchPriority */ fetchPriority, integrity,
referrerPolicy, mode == nsHtml5TreeBuilder::IN_HEAD, false, false, true);
}
}
}
}
} elseif (nsGkAtoms::video == aName) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_POSTER); if (url) { // Fetch priority is not supported for video. Nullptr will map to // the auto state // (https://html.spec.whatwg.org/#fetch-priority-attribute). auto fetchPriority = nullptr;
mSpeculativeLoadQueue.AppendElement()->InitImage(
url, nullptr, nullptr, nullptr, nullptr, nullptr, false,
fetchPriority);
}
} elseif (nsGkAtoms::style == aName) {
mImportScanner.Start();
nsHtml5TreeOperation* treeOp =
mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(
NS_ERROR_OUT_OF_MEMORY); return nullptr;
}
opSetStyleLineNumber operation(content, tokenizer->getLineNumber());
treeOp->Init(mozilla::AsVariant(operation));
} elseif (nsGkAtoms::html == aName) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_MANIFEST);
mSpeculativeLoadQueue.AppendElement()->InitManifest(url);
} elseif (nsGkAtoms::base == aName) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (url) {
mSpeculativeLoadQueue.AppendElement()->InitBase(url);
}
} elseif (nsGkAtoms::meta == aName) { if (nsHtml5Portability::lowerCaseLiteralEqualsIgnoreAsciiCaseString( "content-security-policy",
aAttributes->getValue(
nsHtml5AttributeName::ATTR_HTTP_EQUIV))) {
nsHtml5String csp =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CONTENT); if (csp) {
mSpeculativeLoadQueue.AppendElement()->InitMetaCSP(csp);
}
} elseif (nsHtml5Portability::
lowerCaseLiteralEqualsIgnoreAsciiCaseString( "referrer",
aAttributes->getValue(
nsHtml5AttributeName::ATTR_NAME))) {
nsHtml5String referrerPolicy =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CONTENT); if (referrerPolicy) {
mSpeculativeLoadQueue.AppendElement()->InitMetaReferrerPolicy(
referrerPolicy);
}
}
} break; case kNameSpaceID_SVG: if (nsGkAtoms::image == aName) {
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (!url) {
url = aAttributes->getValue(nsHtml5AttributeName::ATTR_XLINK_HREF);
} if (url) { // Currently SVG's `<image>` element lacks support for // `fetchpriority`, see bug 1847712. Hence passing nullptr which // maps to the auto state // (https://html.spec.whatwg.org/#fetch-priority-attribute). auto fetchPriority = nullptr;
if (importmap) { // If we see an importmap, we don't want to later start speculative // loads for modulepreloads, since such load might finish before // the importmap is created. This also applies to module scripts so // that any modulepreload integrity checks can be performed before // the modules scripts are loaded. // This state is not part of speculation rollback: If an importmap // is seen speculatively and the speculation is rolled back, the // importmap is still considered seen. // TODO: Sync importmap seenness between the main thread and the // parser thread. // https://bugzilla.mozilla.org/show_bug.cgi?id=1848312
mHasSeenImportMap = true;
}
nsHtml5String url =
aAttributes->getValue(nsHtml5AttributeName::ATTR_HREF); if (!url) {
url = aAttributes->getValue(nsHtml5AttributeName::ATTR_XLINK_HREF);
} if (url) {
async = aAttributes->contains(nsHtml5AttributeName::ATTR_ASYNC);
defer = aAttributes->contains(nsHtml5AttributeName::ATTR_DEFER); if ((isModule && !mHasSeenImportMap) || (!isModule && !importmap)) {
nsHtml5String type =
aAttributes->getValue(nsHtml5AttributeName::ATTR_TYPE);
nsHtml5String crossOrigin =
aAttributes->getValue(nsHtml5AttributeName::ATTR_CROSSORIGIN);
nsHtml5String nonce =
aAttributes->getValue(nsHtml5AttributeName::ATTR_NONCE);
nsHtml5String integrity =
aAttributes->getValue(nsHtml5AttributeName::ATTR_INTEGRITY);
nsHtml5String referrerPolicy = aAttributes->getValue(
nsHtml5AttributeName::ATTR_REFERRERPOLICY);
// Bug 1847712: SVG's `<script>` element doesn't support // `fetchpriority` yet. // Use the empty string and rely on the // "invalid value default" state being used later. // Compared to using a non-empty string, this doesn't // require calling `Release()` for the string.
nsHtml5String fetchPriority = nsHtml5String::EmptyString();
mSpeculativeLoadQueue.AppendElement()->InitScript(
url, nullptr, type, crossOrigin, /* aMedia = */ nullptr,
nonce, fetchPriority, integrity, referrerPolicy,
mode == nsHtml5TreeBuilder::IN_HEAD, async, defer, false);
}
} // `mCurrentHtmlScriptCannotDocumentWriteOrBlock` MUST be computed to // match the ScriptLoader-perceived kind of the script regardless of // enqueuing a speculative load. Either the attribute prevents a // classic script execution or is ignored on a module script.
mCurrentHtmlScriptCannotDocumentWriteOrBlock =
isModule || importmap || async || defer;
} elseif (nsGkAtoms::style == aName) {
mImportScanner.Start();
nsHtml5TreeOperation* treeOp =
mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(
NS_ERROR_OUT_OF_MEMORY); return nullptr;
}
opSetStyleLineNumber operation(content, tokenizer->getLineNumber());
treeOp->Init(mozilla::AsVariant(operation));
} break;
}
} elseif (aNamespace != kNameSpaceID_MathML) { // No speculative loader--just line numbers and defer/async check if (nsGkAtoms::style == aName) {
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return nullptr;
}
opSetStyleLineNumber operation(content, tokenizer->getLineNumber());
treeOp->Init(mozilla::AsVariant(operation));
} elseif (nsGkAtoms::script == aName) {
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return nullptr;
}
opSetScriptLineAndColumnNumberAndFreeze operation(
content, tokenizer->getLineNumber(), // NOTE: tokenizer->getColumnNumber() points '>'.
tokenizer->getColumnNumber() + 1);
treeOp->Init(mozilla::AsVariant(operation)); if (aNamespace == kNameSpaceID_XHTML) { // Although we come here in cases where the value of // `mCurrentHtmlScriptCannotDocumentWriteOrBlock` doesn't actually // matter, we also come here when parsing document.written content on // the main thread. In that case, IT MATTERS that // `mCurrentHtmlScriptCannotDocumentWriteOrBlock` is set correctly, // so let's just always set it correctly even if it a bit of wasted work // in the scenarios where no scripts execute and it doesn't matter. // // See the comments around generating speculative loads for HTML scripts // elements for the details of when // `mCurrentHtmlScriptCannotDocumentWriteOrBlock` needs to be set to // `true` and when to `false`.
nsHtml5String type =
aAttributes->getValue(nsHtml5AttributeName::ATTR_TYPE);
nsAutoString typeString;
getTypeString(type, typeString);
if (mBuilder) { // Get the foster parent to use as the intended parent when creating // the child element.
nsIContent* fosterParent = nsHtml5TreeOperation::GetFosterParent( static_cast<nsIContent*>(aTable), static_cast<nsIContent*>(aStackParent));
// Tree op to get the foster parent that we use as the intended parent // when creating the child element.
nsHtml5TreeOperation* fosterParentTreeOp = mOpQueue.AppendElement();
NS_ASSERTION(fosterParentTreeOp, "Tree op allocation failed.");
nsIContentHandle* fosterParentHandle = AllocateContentHandle();
opGetFosterParent operation(aTable, aStackParent, fosterParentHandle);
fosterParentTreeOp->Init(mozilla::AsVariant(operation));
// Create the element with the correct intended parent.
nsIContentHandle* child =
createElement(aNamespace, aName, aAttributes, aFormElement,
fosterParentHandle, aCreator);
// Insert the child into the foster parent.
insertFosterParentedChild(child, aTable, aStackParent);
auto bufferCopy = mozilla::MakeUniqueFallible<char16_t[]>(aLength); if (!bufferCopy) { // Just assigning mBroken instead of generating tree op. The caller // of tokenizeBuffer() will call MarkAsBroken() as appropriate.
mBroken = NS_ERROR_OUT_OF_MEMORY;
requestSuspension(); return;
}
auto bufferCopy = mozilla::MakeUniqueFallible<char16_t[]>(aLength); if (!bufferCopy) { // Just assigning mBroken instead of generating tree op. The caller // of tokenizeBuffer() will call MarkAsBroken() as appropriate.
mBroken = NS_ERROR_OUT_OF_MEMORY;
requestSuspension(); return;
}
auto bufferCopy = mozilla::MakeUniqueFallible<char16_t[]>(aLength); if (!bufferCopy) { // Just assigning mBroken instead of generating tree op. The caller // of tokenizeBuffer() will call MarkAsBroken() as appropriate.
mBroken = NS_ERROR_OUT_OF_MEMORY;
requestSuspension(); return;
}
auto bufferCopy = mozilla::MakeUniqueFallible<char16_t[]>(aLength); if (!bufferCopy) { // Just assigning mBroken instead of generating tree op. The caller // of tokenizeBuffer() will call MarkAsBroken() as appropriate.
mBroken = NS_ERROR_OUT_OF_MEMORY;
requestSuspension(); return;
}
if (aAttributes == nsHtml5HtmlAttributes::EMPTY_ATTRIBUTES) { return;
}
if (mBuilder) {
MOZ_ASSERT(
aAttributes == tokenizer->GetAttributes(), "Using attribute other than the tokenizer's to add to body or html.");
nsresult rv = nsHtml5TreeOperation::AddAttributes( static_cast<nsIContent*>(aElement), aAttributes, mBuilder); if (NS_FAILED(rv)) {
MarkAsBrokenAndRequestSuspensionWithBuilder(rv);
} return;
}
void nsHtml5TreeBuilder::appendDoctypeToDocument(nsAtom* aName,
nsHtml5String aPublicId,
nsHtml5String aSystemId) {
MOZ_ASSERT(aName, "Null name");
nsString publicId; // Not Auto, because using it to hold nsStringBuffer*
nsString systemId; // Not Auto, because using it to hold nsStringBuffer*
aPublicId.ToString(publicId);
aSystemId.ToString(systemId); if (mBuilder) {
nsresult rv = nsHtml5TreeOperation::AppendDoctypeToDocument(
aName, publicId, systemId, mBuilder); if (NS_FAILED(rv)) {
MarkAsBrokenAndRequestSuspensionWithBuilder(rv);
} return;
}
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opAppendDoctypeToDocument operation(aName, publicId, systemId);
treeOp->Init(mozilla::AsVariant(operation)); // nsXMLContentSink can flush here, but what's the point? // It can also interrupt here, but we can't.
}
void nsHtml5TreeBuilder::elementPushed(int32_t aNamespace, nsAtom* aName,
nsIContentHandle* aElement) {
NS_ASSERTION(aNamespace == kNameSpaceID_XHTML ||
aNamespace == kNameSpaceID_SVG ||
aNamespace == kNameSpaceID_MathML, "Element isn't HTML, SVG or MathML!");
NS_ASSERTION(aName, "Element doesn't have local name!");
NS_ASSERTION(aElement, "No element!"); /* * The frame constructor uses recursive algorithms, so it can't deal with * arbitrarily deep trees. This is especially a problem on Windows where * the permitted depth of the runtime stack is rather small. * * The following is a protection against author incompetence--not against * malice. There are other ways to make the DOM deep anyway. * * The basic idea is that when the tree builder stack gets too deep, * append operations no longer append to the node that the HTML parsing * algorithm says they should but instead text nodes are append to the last * element that was seen before a magic tree builder stack threshold was * reached and element and comment nodes aren't appended to the DOM at all. * * However, for security reasons, non-child descendant text nodes inside an * SVG script or style element should not become children. Also, non-cell * table elements shouldn't be used as surrogate parents for user experience * reasons.
*/
if (MOZ_UNLIKELY(isInSVGOddPCData)) { // We are seeing an element that has children, which could not have child // elements in HTML, i.e., is parsed as PCDATA in SVG but CDATA in HTML.
mozilla::glean::parsing::svg_unusual_pcdata.AddToNumerator(1);
} if (MOZ_UNLIKELY(aNamespace == kNameSpaceID_SVG)) { if ((aName == nsGkAtoms::style) || (aName == nsGkAtoms::xmp) ||
(aName == nsGkAtoms::iframe) || (aName == nsGkAtoms::noembed) ||
(aName == nsGkAtoms::noframes) || (aName == nsGkAtoms::noscript) ||
(aName == nsGkAtoms::script)) {
isInSVGOddPCData++;
}
}
if (aNamespace != kNameSpaceID_XHTML) { return;
} if (aName == nsGkAtoms::body || aName == nsGkAtoms::frameset) { if (mBuilder) { // InnerHTML and DOMParser shouldn't start layout anyway return;
}
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
treeOp->Init(mozilla::AsVariant(opStartLayout())); return;
} if (nsIContent::RequiresDoneCreatingElement(kNameSpaceID_XHTML, aName)) { if (mBuilder) {
nsHtml5TreeOperation::DoneCreatingElement( static_cast<nsIContent*>(aElement));
} else {
opDoneCreatingElement operation(aElement);
mOpQueue.AppendElement()->Init(mozilla::AsVariant(operation));
} return;
} if (mGenerateSpeculativeLoads && aName == nsGkAtoms::picture) { // See comments in nsHtml5SpeculativeLoad.h about <picture> preloading
mSpeculativeLoadQueue.AppendElement()->InitOpenPicture(); return;
} if (aName == nsGkAtoms::_template) { if (tokenizer->TemplatePushedOrHeadPopped()) {
requestSuspension();
}
}
}
void nsHtml5TreeBuilder::elementPopped(int32_t aNamespace, nsAtom* aName,
nsIContentHandle* aElement) {
NS_ASSERTION(aNamespace == kNameSpaceID_XHTML ||
aNamespace == kNameSpaceID_SVG ||
aNamespace == kNameSpaceID_MathML, "Element isn't HTML, SVG or MathML!");
NS_ASSERTION(aName, "Element doesn't have local name!");
NS_ASSERTION(aElement, "No element!"); if (aNamespace == kNameSpaceID_MathML) { return;
} if (MOZ_UNLIKELY(aNamespace == kNameSpaceID_SVG)) { if ((aName == nsGkAtoms::style) || (aName == nsGkAtoms::xmp) ||
(aName == nsGkAtoms::iframe) || (aName == nsGkAtoms::noembed) ||
(aName == nsGkAtoms::noframes) || (aName == nsGkAtoms::noscript) ||
(aName == nsGkAtoms::script)) {
isInSVGOddPCData--;
}
} // we now have only SVG and HTML if (aName == nsGkAtoms::script) { if (mPreventScriptExecution) { if (mBuilder) {
nsHtml5TreeOperation::PreventScriptExecution( static_cast<nsIContent*>(aElement)); return;
}
opPreventScriptExecution operation(aElement);
mOpQueue.AppendElement()->Init(mozilla::AsVariant(operation)); return;
} if (mBuilder) { return;
} if (mCurrentHtmlScriptCannotDocumentWriteOrBlock) {
NS_ASSERTION(
aNamespace == kNameSpaceID_XHTML || aNamespace == kNameSpaceID_SVG, "Only HTML and SVG scripts may be async/defer.");
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opRunScriptThatCannotDocumentWriteOrBlock operation(aElement);
treeOp->Init(mozilla::AsVariant(operation));
mCurrentHtmlScriptCannotDocumentWriteOrBlock = false; return;
}
requestSuspension();
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opRunScriptThatMayDocumentWriteOrBlock operation(aElement, nullptr);
treeOp->Init(mozilla::AsVariant(operation)); return;
} // Some nodes need DoneAddingChildren() called to initialize // properly (e.g. form state restoration). if (nsIContent::RequiresDoneAddingChildren(aNamespace, aName)) { if (mBuilder) {
nsHtml5TreeOperation::DoneAddingChildren( static_cast<nsIContent*>(aElement)); return;
}
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opDoneAddingChildren operation(aElement);
treeOp->Init(mozilla::AsVariant(operation)); if (aNamespace == kNameSpaceID_XHTML && aName == nsGkAtoms::head) { if (tokenizer->TemplatePushedOrHeadPopped()) {
requestSuspension();
}
} return;
} if (aName == nsGkAtoms::style ||
(aNamespace == kNameSpaceID_XHTML && aName == nsGkAtoms::link)) { if (mBuilder) {
MOZ_ASSERT(!nsContentUtils::IsSafeToRunScript(), "Scripts must be blocked.");
mBuilder->UpdateStyleSheet(static_cast<nsIContent*>(aElement)); return;
}
if (aName == nsGkAtoms::style) {
nsTArray<nsString> imports = mImportScanner.Stop(); for (nsString& url : imports) {
mSpeculativeLoadQueue.AppendElement()->InitImportStyle(std::move(url));
}
}
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opUpdateStyleSheet operation(aElement);
treeOp->Init(mozilla::AsVariant(operation)); return;
} if (aNamespace == kNameSpaceID_SVG) { if (aName == nsGkAtoms::svg) { if (!scriptingEnabled || mPreventScriptExecution) { return;
} if (mBuilder) {
nsHtml5TreeOperation::SvgLoad(static_cast<nsIContent*>(aElement)); return;
}
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opSvgLoad operation(aElement);
treeOp->Init(mozilla::AsVariant(operation));
} return;
}
if (mGenerateSpeculativeLoads && aName == nsGkAtoms::picture) { // See comments in nsHtml5SpeculativeLoad.h about <picture> preloading
mSpeculativeLoadQueue.AppendElement()->InitEndPicture(); return;
}
}
void nsHtml5TreeBuilder::accumulateCharacters(const char16_t* aBuf,
int32_t aStart, int32_t aLength) {
MOZ_RELEASE_ASSERT(charBufferLen + aLength <= charBuffer.length, "About to memcpy past the end of the buffer!");
memcpy(charBuffer + charBufferLen, aBuf + aStart, sizeof(char16_t) * aLength);
charBufferLen += aLength;
}
// INT32_MAX is (2^31)-1. Therefore, the highest power-of-two that fits // is 2^30. Note that this is counting char16_t units. The underlying // bytes will be twice that, but they fit even in 32-bit size_t even // if a contiguous chunk of memory of that size is pretty unlikely to // be available on a 32-bit system. #define MAX_POWER_OF_TWO_IN_INT32 0x40000000
bool nsHtml5TreeBuilder::EnsureBufferSpace(int32_t aLength) { // TODO: Unify nsHtml5Tokenizer::strBuf and nsHtml5TreeBuilder::charBuffer // so that this method becomes unnecessary.
mozilla::CheckedInt<int32_t> worstCase(charBufferLen);
worstCase += aLength; if (!worstCase.isValid()) { returnfalse;
} if (worstCase.value() > MAX_POWER_OF_TWO_IN_INT32) { returnfalse;
} if (!charBuffer) { if (worstCase.value() < MAX_POWER_OF_TWO_IN_INT32) { // Add one to round to the next power of two to avoid immediate // reallocation once there are a few characters in the buffer.
worstCase += 1;
}
charBuffer = jArray<char16_t, int32_t>::newFallibleJArray(
mozilla::RoundUpPow2(worstCase.value())); if (!charBuffer) { returnfalse;
}
} elseif (worstCase.value() > charBuffer.length) {
jArray<char16_t, int32_t> newBuf =
jArray<char16_t, int32_t>::newFallibleJArray(
mozilla::RoundUpPow2(worstCase.value())); if (!newBuf) { returnfalse;
}
memcpy(newBuf, charBuffer, sizeof(char16_t) * size_t(charBufferLen));
charBuffer = newBuf;
} returntrue;
}
nsIContentHandle* nsHtml5TreeBuilder::AllocateContentHandle() { if (MOZ_UNLIKELY(mBuilder)) {
MOZ_ASSERT_UNREACHABLE("Must never allocate a handle with builder."); return nullptr;
} if (mHandlesUsed == NS_HTML5_TREE_BUILDER_HANDLE_ARRAY_LENGTH) {
mOldHandles.AppendElement(std::move(mHandles));
mHandles = mozilla::MakeUnique<nsIContent*[]>(
NS_HTML5_TREE_BUILDER_HANDLE_ARRAY_LENGTH);
mHandlesUsed = 0;
} #ifdef DEBUG
mHandles[mHandlesUsed] = reinterpret_cast<nsIContent*>(uintptr_t(0xC0DEDBAD)); #endif return &mHandles[mHandlesUsed++];
}
bool nsHtml5TreeBuilder::HasScriptThatMayDocumentWriteOrBlock() {
uint32_t len = mOpQueue.Length(); if (!len) { returnfalse;
} return mOpQueue.ElementAt(len - 1).IsRunScriptThatMayDocumentWriteOrBlock();
}
mozilla::Result<bool, nsresult> nsHtml5TreeBuilder::Flush(bool aDiscretionary) { if (MOZ_UNLIKELY(mBuilder)) {
MOZ_ASSERT_UNREACHABLE("Must never flush with builder."); returnfalse;
} if (NS_SUCCEEDED(mBroken)) { if (!aDiscretionary || !(charBufferLen && currentPtr >= 0 &&
stack[currentPtr]->isFosterParenting())) { // Don't flush text on discretionary flushes if the current element on // the stack is a foster-parenting element and there's pending text, // because flushing in that case would make the tree shape dependent on // where the flush points fall.
flushCharacters();
}
FlushLoads();
} if (mOpSink) { bool hasOps = !mOpQueue.IsEmpty(); if (hasOps) { // If the builder is broken and mOpQueue is not empty, there must be // one op and it must be eTreeOpMarkAsBroken. if (NS_FAILED(mBroken)) {
MOZ_ASSERT(mOpQueue.Length() == 1, "Tree builder is broken with a non-empty op queue whose " "length isn't 1.");
MOZ_ASSERT(mOpQueue[0].IsMarkAsBroken(), "Tree builder is broken but the op in queue is not marked " "as broken.");
} if (!mOpSink->MoveOpsFrom(mOpQueue)) { return mozilla::Err(NS_ERROR_OUT_OF_MEMORY);
}
} return hasOps;
} // no op sink: throw away ops
mOpQueue.Clear(); returnfalse;
}
void nsHtml5TreeBuilder::FlushLoads() { if (MOZ_UNLIKELY(mBuilder)) {
MOZ_ASSERT_UNREACHABLE("Must never flush loads with builder."); return;
} if (!mSpeculativeLoadQueue.IsEmpty()) {
mSpeculativeLoadStage->MoveSpeculativeLoadsFrom(mSpeculativeLoadQueue);
}
}
void nsHtml5TreeBuilder::SetDocumentCharset(NotNull<const Encoding*> aEncoding,
nsCharsetSource aCharsetSource, bool aCommitEncodingSpeculation) {
MOZ_ASSERT(!mBuilder, "How did we call this with builder?");
MOZ_ASSERT(mSpeculativeLoadStage, "How did we call this without a speculative load stage?");
mSpeculativeLoadQueue.AppendElement()->InitSetDocumentCharset(
aEncoding, aCharsetSource, aCommitEncodingSpeculation);
}
void nsHtml5TreeBuilder::UpdateCharsetSource(nsCharsetSource aCharsetSource) {
MOZ_ASSERT(!mBuilder, "How did we call this with builder?");
MOZ_ASSERT(mSpeculativeLoadStage, "How did we call this without a speculative load stage (even " "though we don't need it right here)?"); if (mViewSource) {
mViewSource->UpdateCharsetSource(aCharsetSource); return;
}
opUpdateCharsetSource operation(aCharsetSource);
mOpQueue.AppendElement()->Init(mozilla::AsVariant(operation));
}
void nsHtml5TreeBuilder::StreamEnded() {
MOZ_ASSERT(!mBuilder, "Must not call StreamEnded with builder.");
MOZ_ASSERT(!fragment, "Must not parse fragments off the main thread.");
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
treeOp->Init(mozilla::AsVariant(opStreamEnded()));
}
void nsHtml5TreeBuilder::NeedsCharsetSwitchTo(
NotNull<const Encoding*> aEncoding, int32_t aCharsetSource,
int32_t aLineNumber) { if (MOZ_UNLIKELY(mBuilder)) {
MOZ_ASSERT_UNREACHABLE("Must never switch charset with builder."); return;
}
nsHtml5TreeOperation* treeOp = mOpQueue.AppendElement(mozilla::fallible); if (MOZ_UNLIKELY(!treeOp)) {
MarkAsBrokenAndRequestSuspensionWithoutBuilder(NS_ERROR_OUT_OF_MEMORY); return;
}
opCharsetSwitchTo opeation(aEncoding, aCharsetSource, aLineNumber);
treeOp->Init(mozilla::AsVariant(opeation));
}
void nsHtml5TreeBuilder::MaybeComplainAboutCharset(constchar* aMsgId, bool aError,
int32_t aLineNumber) { if (MOZ_UNLIKELY(mBuilder)) {
MOZ_ASSERT_UNREACHABLE("Must never complain about charset with builder."); return;
}
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