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fune/dom/script/ScriptLoader.cpp
Jon Coppeard c095a8dbd4 Bug 1865410 - Part 1: Don't use preload requests after an import map is registered r=smaug 
We stop speculative preloading of module scripts after seeing an import map.
However it can still happen that we see a preload request for script element
after an import map is registered because a script can dynamically insert an
import map after preloading has happened.

Don't use these preloads as they may have incorrectly resolved module
specifiers.

We can remove the previous way of dealing with this issue where we removed
preloaded modules from the module map if we later loaded an import map. This is
not safe as modules could be present in the module map for other valid reasons,
e.g. if they have been imported by another script.

Differential Revision: https://phabricator.services.mozilla.com/D194766
2023-12-02 08:49:59 +00:00

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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "ScriptLoader.h"
#include "ScriptLoadHandler.h"
#include "ScriptTrace.h"
#include "ModuleLoader.h"
#include "nsGenericHTMLElement.h"
#include "mozilla/Assertions.h"
#include "mozilla/dom/FetchPriority.h"
#include "mozilla/dom/RequestBinding.h"
#include "nsIChildChannel.h"
#include "zlib.h"
#include "prsystem.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "js/Array.h" // JS::GetArrayLength
#include "js/ColumnNumber.h" // JS::ColumnNumberOneOrigin
#include "js/CompilationAndEvaluation.h"
#include "js/CompileOptions.h" // JS::CompileOptions, JS::OwningCompileOptions, JS::DecodeOptions, JS::OwningDecodeOptions, JS::DelazificationOption
#include "js/ContextOptions.h" // JS::ContextOptionsRef
#include "js/experimental/JSStencil.h" // JS::Stencil, JS::InstantiationStorage
#include "js/experimental/CompileScript.h" // JS::FrontendContext, JS::NewFrontendContext, JS::DestroyFrontendContext, JS::SetNativeStackQuota, JS::ThreadStackQuotaForSize, JS::CompilationStorage, JS::CompileGlobalScriptToStencil, JS::CompileModuleScriptToStencil, JS::DecodeStencil, JS::PrepareForInstantiate
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "js/loader/ScriptLoadRequest.h"
#include "ScriptCompression.h"
#include "js/loader/LoadedScript.h"
#include "js/loader/ModuleLoadRequest.h"
#include "js/MemoryFunctions.h"
#include "js/Modules.h"
#include "js/PropertyAndElement.h" // JS_DefineProperty
#include "js/Realm.h"
#include "js/SourceText.h"
#include "js/Transcoding.h" // JS::TranscodeRange, JS::TranscodeResult, JS::IsTranscodeFailureResult
#include "js/Utility.h"
#include "xpcpublic.h"
#include "GeckoProfiler.h"
#include "nsContentSecurityManager.h"
#include "nsCycleCollectionParticipant.h"
#include "nsIContent.h"
#include "nsJSUtils.h"
#include "mozilla/dom/AutoEntryScript.h"
#include "mozilla/dom/DocGroup.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/JSExecutionContext.h"
#include "mozilla/dom/ScriptDecoding.h" // mozilla::dom::ScriptDecoding
#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/dom/SRILogHelper.h"
#include "mozilla/dom/WindowContext.h"
#include "mozilla/Mutex.h" // mozilla::Mutex
#include "mozilla/net/UrlClassifierFeatureFactory.h"
#include "mozilla/Preferences.h"
#include "mozilla/StaticPrefs_dom.h"
#include "mozilla/StaticPrefs_javascript.h"
#include "mozilla/StaticPrefs_network.h"
#include "nsAboutProtocolUtils.h"
#include "nsGkAtoms.h"
#include "nsNetUtil.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScriptContext.h"
#include "nsIPrincipal.h"
#include "nsJSPrincipals.h"
#include "nsContentPolicyUtils.h"
#include "nsIClassifiedChannel.h"
#include "nsIHttpChannel.h"
#include "nsIHttpChannelInternal.h"
#include "nsIClassOfService.h"
#include "nsICacheInfoChannel.h"
#include "nsITimedChannel.h"
#include "nsIScriptElement.h"
#include "nsISupportsPriority.h"
#include "nsIDocShell.h"
#include "nsContentUtils.h"
#include "nsUnicharUtils.h"
#include "nsError.h"
#include "nsThreadUtils.h"
#include "nsDocShellCID.h"
#include "nsIContentSecurityPolicy.h"
#include "mozilla/Logging.h"
#include "nsCRT.h"
#include "nsContentCreatorFunctions.h"
#include "nsProxyRelease.h"
#include "nsSandboxFlags.h"
#include "nsContentTypeParser.h"
#include "nsINetworkPredictor.h"
#include "nsMimeTypes.h"
#include "mozilla/ConsoleReportCollector.h"
#include "mozilla/CycleCollectedJSContext.h"
#include "mozilla/EventQueue.h"
#include "mozilla/LoadInfo.h"
#include "ReferrerInfo.h"
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/Attributes.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/TaskController.h"
#include "mozilla/Telemetry.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/Unused.h"
#include "mozilla/Utf8.h" // mozilla::Utf8Unit
#include "nsIScriptError.h"
#include "nsIAsyncOutputStream.h"
#include "js/loader/ModuleLoaderBase.h"
#include "mozilla/Maybe.h"
using JS::SourceText;
using namespace JS::loader;
using mozilla::Telemetry::LABELS_DOM_SCRIPT_PRELOAD_RESULT;
namespace mozilla::dom {
LazyLogModule ScriptLoader::gCspPRLog("CSP");
LazyLogModule ScriptLoader::gScriptLoaderLog("ScriptLoader");
#undef LOG
#define LOG(args) \
MOZ_LOG(ScriptLoader::gScriptLoaderLog, mozilla::LogLevel::Debug, args)
#define LOG_ENABLED() \
MOZ_LOG_TEST(ScriptLoader::gScriptLoaderLog, mozilla::LogLevel::Debug)
// Alternate Data MIME type used by the ScriptLoader to register that we want to
// store bytecode without reading it.
static constexpr auto kNullMimeType = "javascript/null"_ns;
/////////////////////////////////////////////////////////////
// AsyncCompileShutdownObserver
/////////////////////////////////////////////////////////////
NS_IMPL_ISUPPORTS(AsyncCompileShutdownObserver, nsIObserver)
void AsyncCompileShutdownObserver::OnShutdown() {
if (mScriptLoader) {
mScriptLoader->Destroy();
MOZ_ASSERT(!mScriptLoader);
}
}
void AsyncCompileShutdownObserver::Unregister() {
if (mScriptLoader) {
mScriptLoader = nullptr;
nsContentUtils::UnregisterShutdownObserver(this);
}
}
NS_IMETHODIMP
AsyncCompileShutdownObserver::Observe(nsISupports* aSubject, const char* aTopic,
const char16_t* aData) {
OnShutdown();
return NS_OK;
}
//////////////////////////////////////////////////////////////
// ScriptLoader::PreloadInfo
//////////////////////////////////////////////////////////////
inline void ImplCycleCollectionUnlink(ScriptLoader::PreloadInfo& aField) {
ImplCycleCollectionUnlink(aField.mRequest);
}
inline void ImplCycleCollectionTraverse(
nsCycleCollectionTraversalCallback& aCallback,
ScriptLoader::PreloadInfo& aField, const char* aName, uint32_t aFlags = 0) {
ImplCycleCollectionTraverse(aCallback, aField.mRequest, aName, aFlags);
}
//////////////////////////////////////////////////////////////
// ScriptLoader
//////////////////////////////////////////////////////////////
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ScriptLoader)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION(ScriptLoader, mNonAsyncExternalScriptInsertedRequests,
mLoadingAsyncRequests, mLoadedAsyncRequests,
mOffThreadCompilingRequests, mDeferRequests,
mXSLTRequests, mParserBlockingRequest,
mBytecodeEncodingQueue, mPreloads,
mPendingChildLoaders, mModuleLoader,
mWebExtModuleLoaders, mShadowRealmModuleLoaders)
NS_IMPL_CYCLE_COLLECTING_ADDREF(ScriptLoader)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ScriptLoader)
ScriptLoader::ScriptLoader(Document* aDocument)
: mDocument(aDocument),
mParserBlockingBlockerCount(0),
mBlockerCount(0),
mNumberOfProcessors(0),
mTotalFullParseSize(0),
mPhysicalSizeOfMemory(-1),
mEnabled(true),
mDeferEnabled(false),
mSpeculativeOMTParsingEnabled(false),
mDeferCheckpointReached(false),
mBlockingDOMContentLoaded(false),
mLoadEventFired(false),
mGiveUpEncoding(false),
mReporter(new ConsoleReportCollector()) {
LOG(("ScriptLoader::ScriptLoader %p", this));
mSpeculativeOMTParsingEnabled = StaticPrefs::
dom_script_loader_external_scripts_speculative_omt_parse_enabled();
mShutdownObserver = new AsyncCompileShutdownObserver(this);
nsContentUtils::RegisterShutdownObserver(mShutdownObserver);
}
ScriptLoader::~ScriptLoader() {
LOG(("ScriptLoader::~ScriptLoader %p", this));
mObservers.Clear();
if (mParserBlockingRequest) {
FireScriptAvailable(NS_ERROR_ABORT, mParserBlockingRequest);
}
for (ScriptLoadRequest* req = mXSLTRequests.getFirst(); req;
req = req->getNext()) {
FireScriptAvailable(NS_ERROR_ABORT, req);
}
for (ScriptLoadRequest* req = mDeferRequests.getFirst(); req;
req = req->getNext()) {
FireScriptAvailable(NS_ERROR_ABORT, req);
}
for (ScriptLoadRequest* req = mLoadingAsyncRequests.getFirst(); req;
req = req->getNext()) {
FireScriptAvailable(NS_ERROR_ABORT, req);
}
for (ScriptLoadRequest* req = mLoadedAsyncRequests.getFirst(); req;
req = req->getNext()) {
FireScriptAvailable(NS_ERROR_ABORT, req);
}
for (ScriptLoadRequest* req =
mNonAsyncExternalScriptInsertedRequests.getFirst();
req; req = req->getNext()) {
FireScriptAvailable(NS_ERROR_ABORT, req);
}
// Unblock the kids, in case any of them moved to a different document
// subtree in the meantime and therefore aren't actually going away.
for (uint32_t j = 0; j < mPendingChildLoaders.Length(); ++j) {
mPendingChildLoaders[j]->RemoveParserBlockingScriptExecutionBlocker();
}
for (size_t i = 0; i < mPreloads.Length(); i++) {
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::NotUsed);
}
if (mShutdownObserver) {
mShutdownObserver->Unregister();
mShutdownObserver = nullptr;
}
mModuleLoader = nullptr;
}
void ScriptLoader::SetGlobalObject(nsIGlobalObject* aGlobalObject) {
if (!aGlobalObject) {
// The document is being detached.
CancelAndClearScriptLoadRequests();
return;
}
MOZ_ASSERT(!HasPendingRequests());
if (!mModuleLoader) {
// The module loader is associated with a global object, so don't create it
// until we have a global set.
mModuleLoader = new ModuleLoader(this, aGlobalObject, ModuleLoader::Normal);
}
MOZ_ASSERT(mModuleLoader->GetGlobalObject() == aGlobalObject);
MOZ_ASSERT(aGlobalObject->GetModuleLoader(dom::danger::GetJSContext()) ==
mModuleLoader);
}
void ScriptLoader::RegisterContentScriptModuleLoader(ModuleLoader* aLoader) {
MOZ_ASSERT(aLoader);
MOZ_ASSERT(aLoader->GetScriptLoader() == this);
mWebExtModuleLoaders.AppendElement(aLoader);
}
void ScriptLoader::RegisterShadowRealmModuleLoader(ModuleLoader* aLoader) {
MOZ_ASSERT(aLoader);
MOZ_ASSERT(aLoader->GetScriptLoader() == this);
mShadowRealmModuleLoaders.AppendElement(aLoader);
}
// Collect telemtry data about the cache information, and the kind of source
// which are being loaded, and where it is being loaded from.
static void CollectScriptTelemetry(ScriptLoadRequest* aRequest) {
using namespace mozilla::Telemetry;
MOZ_ASSERT(aRequest->IsFetching());
// Skip this function if we are not running telemetry.
if (!CanRecordExtended()) {
return;
}
// Report the script kind.
if (aRequest->IsModuleRequest()) {
AccumulateCategorical(LABELS_DOM_SCRIPT_KIND::ModuleScript);
} else {
AccumulateCategorical(LABELS_DOM_SCRIPT_KIND::ClassicScript);
}
// Report the type of source. This is used to monitor the status of the
// JavaScript Start-up Bytecode Cache, with the expectation of an almost zero
// source-fallback and alternate-data being roughtly equal to source loads.
if (aRequest->mFetchSourceOnly) {
if (aRequest->GetScriptLoadContext()->mIsInline) {
AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::Inline);
} else if (aRequest->IsTextSource()) {
AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::SourceFallback);
}
} else {
if (aRequest->IsTextSource()) {
AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::Source);
} else if (aRequest->IsBytecode()) {
AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::AltData);
}
}
}
// Helper method for checking if the script element is an event-handler
// This means that it has both a for-attribute and a event-attribute.
// Also, if the for-attribute has a value that matches "\s*window\s*",
// and the event-attribute matches "\s*onload([ \(].*)?" then it isn't an
// eventhandler. (both matches are case insensitive).
// This is how IE seems to filter out a window's onload handler from a
// <script for=... event=...> element.
static bool IsScriptEventHandler(ScriptKind kind, nsIContent* aScriptElement) {
if (kind != ScriptKind::eClassic) {
return false;
}
if (!aScriptElement->IsHTMLElement()) {
return false;
}
nsAutoString forAttr, eventAttr;
if (!aScriptElement->AsElement()->GetAttr(nsGkAtoms::_for, forAttr) ||
!aScriptElement->AsElement()->GetAttr(nsGkAtoms::event, eventAttr)) {
return false;
}
const nsAString& for_str =
nsContentUtils::TrimWhitespace<nsCRT::IsAsciiSpace>(forAttr);
if (!for_str.LowerCaseEqualsLiteral("window")) {
return true;
}
// We found for="window", now check for event="onload".
const nsAString& event_str =
nsContentUtils::TrimWhitespace<nsCRT::IsAsciiSpace>(eventAttr, false);
if (!StringBeginsWith(event_str, u"onload"_ns,
nsCaseInsensitiveStringComparator)) {
// It ain't "onload.*".
return true;
}
nsAutoString::const_iterator start, end;
event_str.BeginReading(start);
event_str.EndReading(end);
start.advance(6); // advance past "onload"
if (start != end && *start != '(' && *start != ' ') {
// We got onload followed by something other than space or
// '('. Not good enough.
return true;
}
return false;
}
nsContentPolicyType ScriptLoadRequestToContentPolicyType(
ScriptLoadRequest* aRequest) {
if (aRequest->GetScriptLoadContext()->IsPreload()) {
return aRequest->IsModuleRequest()
? nsIContentPolicy::TYPE_INTERNAL_MODULE_PRELOAD
: nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD;
}
return aRequest->IsModuleRequest() ? nsIContentPolicy::TYPE_INTERNAL_MODULE
: nsIContentPolicy::TYPE_INTERNAL_SCRIPT;
}
nsresult ScriptLoader::CheckContentPolicy(Document* aDocument,
nsIScriptElement* aElement,
const nsAString& aType,
const nsAString& aNonce,
ScriptLoadRequest* aRequest) {
nsContentPolicyType contentPolicyType =
ScriptLoadRequestToContentPolicyType(aRequest);
nsCOMPtr<nsINode> requestingNode = do_QueryInterface(aElement);
nsCOMPtr<nsILoadInfo> secCheckLoadInfo = new net::LoadInfo(
aDocument->NodePrincipal(), // loading principal
aDocument->NodePrincipal(), // triggering principal
requestingNode, nsILoadInfo::SEC_ONLY_FOR_EXPLICIT_CONTENTSEC_CHECK,
contentPolicyType);
secCheckLoadInfo->SetParserCreatedScript(aElement->GetParserCreated() !=
mozilla::dom::NOT_FROM_PARSER);
// Use nonce of the current element, instead of the preload, because those
// are allowed to differ.
secCheckLoadInfo->SetCspNonce(aNonce);
if (aRequest->mIntegrity.IsValid()) {
MOZ_ASSERT(!aRequest->mIntegrity.IsEmpty());
secCheckLoadInfo->SetIntegrityMetadata(
aRequest->mIntegrity.GetIntegrityString());
}
int16_t shouldLoad = nsIContentPolicy::ACCEPT;
nsresult rv = NS_CheckContentLoadPolicy(
aRequest->mURI, secCheckLoadInfo, NS_LossyConvertUTF16toASCII(aType),
&shouldLoad, nsContentUtils::GetContentPolicy());
if (NS_FAILED(rv) || NS_CP_REJECTED(shouldLoad)) {
if (NS_FAILED(rv) || shouldLoad != nsIContentPolicy::REJECT_TYPE) {
return NS_ERROR_CONTENT_BLOCKED;
}
return NS_ERROR_CONTENT_BLOCKED_SHOW_ALT;
}
return NS_OK;
}
/* static */
bool ScriptLoader::IsAboutPageLoadingChromeURI(ScriptLoadRequest* aRequest,
Document* aDocument) {
// if the uri to be loaded is not of scheme chrome:, there is nothing to do.
if (!aRequest->mURI->SchemeIs("chrome")) {
return false;
}
// we can either get here with a regular contentPrincipal or with a
// NullPrincipal in case we are showing an error page in a sandboxed iframe.
// In either case if the about: page is linkable from content, there is
// nothing to do.
uint32_t aboutModuleFlags = 0;
nsresult rv = NS_OK;
nsCOMPtr<nsIPrincipal> triggeringPrincipal = aRequest->TriggeringPrincipal();
if (triggeringPrincipal->GetIsContentPrincipal()) {
if (!triggeringPrincipal->SchemeIs("about")) {
return false;
}
rv = triggeringPrincipal->GetAboutModuleFlags(&aboutModuleFlags);
NS_ENSURE_SUCCESS(rv, false);
} else if (triggeringPrincipal->GetIsNullPrincipal()) {
nsCOMPtr<nsIURI> docURI = aDocument->GetDocumentURI();
if (!docURI->SchemeIs("about")) {
return false;
}
nsCOMPtr<nsIAboutModule> aboutModule;
rv = NS_GetAboutModule(docURI, getter_AddRefs(aboutModule));
if (NS_FAILED(rv) || !aboutModule) {
return false;
}
rv = aboutModule->GetURIFlags(docURI, &aboutModuleFlags);
NS_ENSURE_SUCCESS(rv, false);
} else {
return false;
}
if (aboutModuleFlags & nsIAboutModule::MAKE_LINKABLE) {
return false;
}
// seems like an about page wants to load a chrome URI.
return true;
}
nsIURI* ScriptLoader::GetBaseURI() const {
MOZ_ASSERT(mDocument);
return mDocument->GetDocBaseURI();
}
class ScriptRequestProcessor : public Runnable {
private:
RefPtr<ScriptLoader> mLoader;
RefPtr<ScriptLoadRequest> mRequest;
public:
ScriptRequestProcessor(ScriptLoader* aLoader, ScriptLoadRequest* aRequest)
: Runnable("dom::ScriptRequestProcessor"),
mLoader(aLoader),
mRequest(aRequest) {}
NS_IMETHOD Run() override { return mLoader->ProcessRequest(mRequest); }
};
void ScriptLoader::RunScriptWhenSafe(ScriptLoadRequest* aRequest) {
auto* runnable = new ScriptRequestProcessor(this, aRequest);
nsContentUtils::AddScriptRunner(runnable);
}
nsresult ScriptLoader::RestartLoad(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->IsBytecode());
aRequest->mScriptBytecode.clearAndFree();
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_fallback");
// Notify preload restart so that we can register this preload request again.
aRequest->GetScriptLoadContext()->NotifyRestart(mDocument);
// Start a new channel from which we explicitly request to stream the source
// instead of the bytecode.
aRequest->mFetchSourceOnly = true;
nsresult rv;
if (aRequest->IsModuleRequest()) {
rv = aRequest->AsModuleRequest()->RestartModuleLoad();
} else {
rv = StartLoad(aRequest, Nothing());
}
if (NS_FAILED(rv)) {
return rv;
}
// Close the current channel and this ScriptLoadHandler as we created a new
// one for the same request.
return NS_BINDING_RETARGETED;
}
nsresult ScriptLoader::StartLoad(
ScriptLoadRequest* aRequest,
const Maybe<nsAutoString>& aCharsetForPreload) {
if (aRequest->IsModuleRequest()) {
return aRequest->AsModuleRequest()->StartModuleLoad();
}
return StartClassicLoad(aRequest, aCharsetForPreload);
}
nsresult ScriptLoader::StartClassicLoad(
ScriptLoadRequest* aRequest,
const Maybe<nsAutoString>& aCharsetForPreload) {
MOZ_ASSERT(aRequest->IsFetching());
NS_ENSURE_TRUE(mDocument, NS_ERROR_NULL_POINTER);
aRequest->SetUnknownDataType();
// If this document is sandboxed without 'allow-scripts', abort.
if (mDocument->HasScriptsBlockedBySandbox()) {
return NS_OK;
}
if (LOG_ENABLED()) {
nsAutoCString url;
aRequest->mURI->GetAsciiSpec(url);
LOG(("ScriptLoadRequest (%p): Start Classic Load (url = %s)", aRequest,
url.get()));
}
nsSecurityFlags securityFlags =
nsContentSecurityManager::ComputeSecurityFlags(
aRequest->CORSMode(), nsContentSecurityManager::CORSSecurityMapping::
CORS_NONE_MAPS_TO_DISABLED_CORS_CHECKS);
securityFlags |= nsILoadInfo::SEC_ALLOW_CHROME;
nsresult rv = StartLoadInternal(aRequest, securityFlags, aCharsetForPreload);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
static bool IsWebExtensionRequest(ScriptLoadRequest* aRequest) {
if (!aRequest->IsModuleRequest()) {
return false;
}
ModuleLoader* loader =
ModuleLoader::From(aRequest->AsModuleRequest()->mLoader);
return loader->GetKind() == ModuleLoader::WebExtension;
}
static nsresult CreateChannelForScriptLoading(nsIChannel** aOutChannel,
Document* aDocument,
ScriptLoadRequest* aRequest,
nsSecurityFlags aSecurityFlags) {
nsContentPolicyType contentPolicyType =
ScriptLoadRequestToContentPolicyType(aRequest);
nsCOMPtr<nsINode> context;
if (aRequest->GetScriptLoadContext()->GetScriptElement()) {
context =
do_QueryInterface(aRequest->GetScriptLoadContext()->GetScriptElement());
} else {
context = aDocument;
}
nsCOMPtr<nsILoadGroup> loadGroup = aDocument->GetDocumentLoadGroup();
nsCOMPtr<nsPIDOMWindowOuter> window = aDocument->GetWindow();
NS_ENSURE_TRUE(window, NS_ERROR_NULL_POINTER);
nsIDocShell* docshell = window->GetDocShell();
nsCOMPtr<nsIInterfaceRequestor> prompter(do_QueryInterface(docshell));
return NS_NewChannelWithTriggeringPrincipal(
aOutChannel, aRequest->mURI, context, aRequest->TriggeringPrincipal(),
aSecurityFlags, contentPolicyType,
nullptr, // aPerformanceStorage
loadGroup, prompter);
}
static void PrepareLoadInfoForScriptLoading(nsIChannel* aChannel,
const ScriptLoadRequest* aRequest) {
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
loadInfo->SetParserCreatedScript(aRequest->ParserMetadata() ==
ParserMetadata::ParserInserted);
loadInfo->SetCspNonce(aRequest->Nonce());
if (aRequest->mIntegrity.IsValid()) {
MOZ_ASSERT(!aRequest->mIntegrity.IsEmpty());
loadInfo->SetIntegrityMetadata(aRequest->mIntegrity.GetIntegrityString());
}
}
// static
void ScriptLoader::PrepareCacheInfoChannel(nsIChannel* aChannel,
ScriptLoadRequest* aRequest) {
// To avoid decoding issues, the build-id is part of the bytecode MIME type
// constant.
aRequest->mCacheInfo = nullptr;
nsCOMPtr<nsICacheInfoChannel> cic(do_QueryInterface(aChannel));
if (cic && StaticPrefs::dom_script_loader_bytecode_cache_enabled()) {
MOZ_ASSERT(!IsWebExtensionRequest(aRequest),
"Can not bytecode cache WebExt code");
if (!aRequest->mFetchSourceOnly) {
// Inform the HTTP cache that we prefer to have information coming from
// the bytecode cache instead of the sources, if such entry is already
// registered.
LOG(("ScriptLoadRequest (%p): Maybe request bytecode", aRequest));
cic->PreferAlternativeDataType(
ScriptLoader::BytecodeMimeTypeFor(aRequest), ""_ns,
nsICacheInfoChannel::PreferredAlternativeDataDeliveryType::ASYNC);
} else {
// If we are explicitly loading from the sources, such as after a
// restarted request, we might still want to save the bytecode after.
//
// The following tell the cache to look for an alternative data type which
// does not exist, such that we can later save the bytecode with a
// different alternative data type.
LOG(("ScriptLoadRequest (%p): Request saving bytecode later", aRequest));
cic->PreferAlternativeDataType(
kNullMimeType, ""_ns,
nsICacheInfoChannel::PreferredAlternativeDataDeliveryType::ASYNC);
}
}
}
static void AdjustPriorityAndClassOfServiceForLinkPreloadScripts(
nsIChannel* aChannel, ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->GetScriptLoadContext()->IsLinkPreloadScript());
if (!StaticPrefs::network_fetchpriority_enabled()) {
// Put it to the group that is not blocked by leaders and doesn't block
// follower at the same time.
// Giving it a much higher priority will make this request be processed
// ahead of other Unblocked requests, but with the same weight as
// Leaders. This will make us behave similar way for both http2 and http1.
ScriptLoadContext::PrioritizeAsPreload(aChannel);
return;
}
if (nsCOMPtr<nsIClassOfService> cos = do_QueryInterface(aChannel)) {
cos->AddClassFlags(nsIClassOfService::Unblocked);
}
if (nsCOMPtr<nsISupportsPriority> supportsPriority =
do_QueryInterface(aChannel)) {
LOG(("Is <link rel=[module]preload"));
const RequestPriority fetchPriority = aRequest->FetchPriority();
// The spec defines the priority to be set in an implementation defined
// manner (<https://fetch.spec.whatwg.org/#concept-fetch>, step 15 and
// <https://html.spec.whatwg.org/#concept-script-fetch-options-fetch-priority>).
// For web-compatibility, the fetch priority mapping from
// <https://web.dev/articles/fetch-priority#browser_priority_and_fetchpriority>
// is taken.
const int32_t supportsPriorityValue = [&]() {
switch (fetchPriority) {
case RequestPriority::Auto: {
return nsISupportsPriority::PRIORITY_HIGH;
}
case RequestPriority::High: {
return nsISupportsPriority::PRIORITY_HIGH;
}
case RequestPriority::Low: {
return nsISupportsPriority::PRIORITY_LOW;
}
default: {
MOZ_ASSERT_UNREACHABLE();
return nsISupportsPriority::PRIORITY_NORMAL;
}
}
}();
LogPriorityMapping(ScriptLoader::gScriptLoaderLog,
ToFetchPriority(fetchPriority), supportsPriorityValue);
supportsPriority->SetPriority(supportsPriorityValue);
}
}
void AdjustPriorityForNonLinkPreloadScripts(nsIChannel* aChannel,
ScriptLoadRequest* aRequest) {
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->IsLinkPreloadScript());
if (!StaticPrefs::network_fetchpriority_enabled()) {
return;
}
if (nsCOMPtr<nsISupportsPriority> supportsPriority =
do_QueryInterface(aChannel)) {
LOG(("Is not <link rel=[module]preload"));
const RequestPriority fetchPriority = aRequest->FetchPriority();
// The spec defines the priority to be set in an implementation defined
// manner (<https://fetch.spec.whatwg.org/#concept-fetch>, step 15 and
// <https://html.spec.whatwg.org/#concept-script-fetch-options-fetch-priority>).
// For web-compatibility, the fetch priority mapping from
// <https://web.dev/articles/fetch-priority#browser_priority_and_fetchpriority>
// is taken.
const Maybe<int32_t> supportsPriorityValue = [&]() -> Maybe<int32_t> {
switch (fetchPriority) {
case RequestPriority::Auto:
return Nothing{};
case RequestPriority::Low: {
return Some(nsISupportsPriority::PRIORITY_LOW);
}
case RequestPriority::High: {
return Some(nsISupportsPriority::PRIORITY_HIGH);
}
default: {
MOZ_ASSERT_UNREACHABLE();
return Nothing{};
}
}
}();
if (supportsPriorityValue) {
LogPriorityMapping(ScriptLoader::gScriptLoaderLog,
ToFetchPriority(fetchPriority),
*supportsPriorityValue);
supportsPriority->SetPriority(*supportsPriorityValue);
}
}
}
// static
void ScriptLoader::PrepareRequestPriorityAndRequestDependencies(
nsIChannel* aChannel, ScriptLoadRequest* aRequest) {
if (aRequest->GetScriptLoadContext()->IsLinkPreloadScript()) {
// This is <link rel="preload" as="script"> or <link rel="modulepreload">
// initiated speculative load
// (https://developer.mozilla.org/en-US/docs/Web/Performance/Speculative_loading).
AdjustPriorityAndClassOfServiceForLinkPreloadScripts(aChannel, aRequest);
ScriptLoadContext::AddLoadBackgroundFlag(aChannel);
} else if (nsCOMPtr<nsIClassOfService> cos = do_QueryInterface(aChannel)) {
AdjustPriorityForNonLinkPreloadScripts(aChannel, aRequest);
if (aRequest->GetScriptLoadContext()->mScriptFromHead &&
aRequest->GetScriptLoadContext()->IsBlockingScript()) {
// synchronous head scripts block loading of most other non js/css
// content such as images, Leader implicitely disallows tailing
cos->AddClassFlags(nsIClassOfService::Leader);
} else if (aRequest->GetScriptLoadContext()->IsDeferredScript() &&
!StaticPrefs::network_http_tailing_enabled()) {
// Bug 1395525 and the !StaticPrefs::network_http_tailing_enabled() bit:
// We want to make sure that turing tailing off by the pref makes the
// browser behave exactly the same way as before landing the tailing
// patch.
// head/body deferred scripts are blocked by leaders but are not
// allowed tailing because they block DOMContentLoaded
cos->AddClassFlags(nsIClassOfService::TailForbidden);
} else {
// other scripts (=body sync or head/body async) are neither blocked
// nor prioritized
cos->AddClassFlags(nsIClassOfService::Unblocked);
if (aRequest->GetScriptLoadContext()->IsAsyncScript()) {
// async scripts are allowed tailing, since those and only those
// don't block DOMContentLoaded; this flag doesn't enforce tailing,
// just overweights the Unblocked flag when the channel is found
// to be a thrird-party tracker and thus set the Tail flag to engage
// tailing.
cos->AddClassFlags(nsIClassOfService::TailAllowed);
}
}
}
}
// static
nsresult ScriptLoader::PrepareHttpRequestAndInitiatorType(
nsIChannel* aChannel, ScriptLoadRequest* aRequest,
const Maybe<nsAutoString>& aCharsetForPreload) {
nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(aChannel));
nsresult rv = NS_OK;
if (httpChannel) {
// HTTP content negotation has little value in this context.
nsAutoCString acceptTypes("*/*");
rv = httpChannel->SetRequestHeader("Accept"_ns, acceptTypes, false);
MOZ_ASSERT(NS_SUCCEEDED(rv));
nsCOMPtr<nsIReferrerInfo> referrerInfo =
new ReferrerInfo(aRequest->mReferrer, aRequest->ReferrerPolicy());
rv = httpChannel->SetReferrerInfoWithoutClone(referrerInfo);
MOZ_ASSERT(NS_SUCCEEDED(rv));
nsCOMPtr<nsIHttpChannelInternal> internalChannel(
do_QueryInterface(httpChannel));
if (internalChannel) {
rv = internalChannel->SetIntegrityMetadata(
aRequest->mIntegrity.GetIntegrityString());
MOZ_ASSERT(NS_SUCCEEDED(rv));
}
nsAutoString hintCharset;
if (!aRequest->GetScriptLoadContext()->IsPreload() &&
aRequest->GetScriptLoadContext()->GetScriptElement()) {
aRequest->GetScriptLoadContext()->GetScriptElement()->GetScriptCharset(
hintCharset);
} else if (aCharsetForPreload.isSome()) {
hintCharset = aCharsetForPreload.ref();
}
rv = httpChannel->SetClassicScriptHintCharset(hintCharset);
NS_ENSURE_SUCCESS(rv, rv);
}
// Set the initiator type
nsCOMPtr<nsITimedChannel> timedChannel(do_QueryInterface(httpChannel));
if (timedChannel) {
if (aRequest->mEarlyHintPreloaderId) {
timedChannel->SetInitiatorType(u"early-hints"_ns);
} else if (aRequest->GetScriptLoadContext()->IsLinkPreloadScript()) {
timedChannel->SetInitiatorType(u"link"_ns);
} else {
timedChannel->SetInitiatorType(u"script"_ns);
}
}
return rv;
}
nsresult ScriptLoader::PrepareIncrementalStreamLoader(
nsIIncrementalStreamLoader** aOutLoader, ScriptLoadRequest* aRequest) {
UniquePtr<mozilla::dom::SRICheckDataVerifier> sriDataVerifier;
if (!aRequest->mIntegrity.IsEmpty()) {
nsAutoCString sourceUri;
if (mDocument->GetDocumentURI()) {
mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri);
}
sriDataVerifier = MakeUnique<SRICheckDataVerifier>(aRequest->mIntegrity,
sourceUri, mReporter);
}
RefPtr<ScriptLoadHandler> handler =
new ScriptLoadHandler(this, aRequest, std::move(sriDataVerifier));
nsresult rv = NS_NewIncrementalStreamLoader(aOutLoader, handler);
NS_ENSURE_SUCCESS(rv, rv);
return rv;
}
nsresult ScriptLoader::StartLoadInternal(
ScriptLoadRequest* aRequest, nsSecurityFlags securityFlags,
const Maybe<nsAutoString>& aCharsetForPreload) {
nsCOMPtr<nsIChannel> channel;
nsresult rv = CreateChannelForScriptLoading(
getter_AddRefs(channel), mDocument, aRequest, securityFlags);
NS_ENSURE_SUCCESS(rv, rv);
if (aRequest->mEarlyHintPreloaderId) {
nsCOMPtr<nsIHttpChannelInternal> channelInternal =
do_QueryInterface(channel);
NS_ENSURE_TRUE(channelInternal != nullptr, NS_ERROR_FAILURE);
rv = channelInternal->SetEarlyHintPreloaderId(
aRequest->mEarlyHintPreloaderId);
NS_ENSURE_SUCCESS(rv, rv);
}
PrepareLoadInfoForScriptLoading(channel, aRequest);
nsCOMPtr<nsIScriptGlobalObject> scriptGlobal = GetScriptGlobalObject();
if (!scriptGlobal) {
return NS_ERROR_FAILURE;
}
ScriptLoader::PrepareCacheInfoChannel(channel, aRequest);
LOG(("ScriptLoadRequest (%p): mode=%u tracking=%d", aRequest,
unsigned(aRequest->GetScriptLoadContext()->mScriptMode),
aRequest->GetScriptLoadContext()->IsTracking()));
PrepareRequestPriorityAndRequestDependencies(channel, aRequest);
rv =
PrepareHttpRequestAndInitiatorType(channel, aRequest, aCharsetForPreload);
NS_ENSURE_SUCCESS(rv, rv);
mozilla::net::PredictorLearn(
aRequest->mURI, mDocument->GetDocumentURI(),
nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE,
mDocument->NodePrincipal()->OriginAttributesRef());
nsCOMPtr<nsIIncrementalStreamLoader> loader;
rv = PrepareIncrementalStreamLoader(getter_AddRefs(loader), aRequest);
NS_ENSURE_SUCCESS(rv, rv);
auto key = PreloadHashKey::CreateAsScript(
aRequest->mURI, aRequest->CORSMode(), aRequest->mKind);
aRequest->GetScriptLoadContext()->NotifyOpen(
key, channel, mDocument,
aRequest->GetScriptLoadContext()->IsLinkPreloadScript(),
aRequest->IsModuleRequest());
rv = channel->AsyncOpen(loader);
if (NS_FAILED(rv)) {
// Make sure to inform any <link preload> tags about failure to load the
// resource.
aRequest->GetScriptLoadContext()->NotifyStart(channel);
aRequest->GetScriptLoadContext()->NotifyStop(rv);
}
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
bool ScriptLoader::PreloadURIComparator::Equals(const PreloadInfo& aPi,
nsIURI* const& aURI) const {
bool same;
return NS_SUCCEEDED(aPi.mRequest->mURI->Equals(aURI, &same)) && same;
}
static bool CSPAllowsInlineScript(nsIScriptElement* aElement,
const nsAString& aNonce,
Document* aDocument) {
nsCOMPtr<nsIContentSecurityPolicy> csp = aDocument->GetCsp();
if (!csp) {
// no CSP --> allow
return true;
}
bool parserCreated =
aElement->GetParserCreated() != mozilla::dom::NOT_FROM_PARSER;
nsCOMPtr<Element> element = do_QueryInterface(aElement);
bool allowInlineScript = false;
nsresult rv = csp->GetAllowsInline(
nsIContentSecurityPolicy::SCRIPT_SRC_ELEM_DIRECTIVE,
false /* aHasUnsafeHash */, aNonce, parserCreated, element,
nullptr /* nsICSPEventListener */, u""_ns,
aElement->GetScriptLineNumber(),
aElement->GetScriptColumnNumber().oneOriginValue(), &allowInlineScript);
return NS_SUCCEEDED(rv) && allowInlineScript;
}
namespace {
RequestPriority FetchPriorityToRequestPriority(
const FetchPriority aFetchPriority) {
switch (aFetchPriority) {
case FetchPriority::High:
return RequestPriority::High;
case FetchPriority::Low:
return RequestPriority::Low;
case FetchPriority::Auto:
return RequestPriority::Auto;
}
MOZ_ASSERT_UNREACHABLE();
return RequestPriority::Auto;
}
} // namespace
already_AddRefed<ScriptLoadRequest> ScriptLoader::CreateLoadRequest(
ScriptKind aKind, nsIURI* aURI, nsIScriptElement* aElement,
nsIPrincipal* aTriggeringPrincipal, CORSMode aCORSMode,
const nsAString& aNonce, RequestPriority aRequestPriority,
const SRIMetadata& aIntegrity, ReferrerPolicy aReferrerPolicy,
ParserMetadata aParserMetadata) {
nsIURI* referrer = mDocument->GetDocumentURIAsReferrer();
nsCOMPtr<Element> domElement = do_QueryInterface(aElement);
RefPtr<ScriptFetchOptions> fetchOptions =
new ScriptFetchOptions(aCORSMode, aNonce, aRequestPriority,
aParserMetadata, aTriggeringPrincipal, domElement);
RefPtr<ScriptLoadContext> context = new ScriptLoadContext();
if (aKind == ScriptKind::eClassic || aKind == ScriptKind::eImportMap) {
RefPtr<ScriptLoadRequest> aRequest =
new ScriptLoadRequest(aKind, aURI, aReferrerPolicy, fetchOptions,
aIntegrity, referrer, context);
return aRequest.forget();
}
MOZ_ASSERT(aKind == ScriptKind::eModule);
RefPtr<ModuleLoadRequest> aRequest = ModuleLoader::CreateTopLevel(
aURI, aReferrerPolicy, fetchOptions, aIntegrity, referrer, this, context);
return aRequest.forget();
}
bool ScriptLoader::ProcessScriptElement(nsIScriptElement* aElement,
const nsAutoString& aTypeAttr) {
// We need a document to evaluate scripts.
NS_ENSURE_TRUE(mDocument, false);
// Check to see if scripts has been turned off.
if (!mEnabled || !mDocument->IsScriptEnabled()) {
return false;
}
NS_ASSERTION(!aElement->IsMalformed(), "Executing malformed script");
nsCOMPtr<nsIContent> scriptContent = do_QueryInterface(aElement);
ScriptKind scriptKind;
if (aElement->GetScriptIsModule()) {
scriptKind = ScriptKind::eModule;
} else if (aElement->GetScriptIsImportMap()) {
scriptKind = ScriptKind::eImportMap;
} else {
scriptKind = ScriptKind::eClassic;
}
// Step 13. Check that the script is not an eventhandler
if (IsScriptEventHandler(scriptKind, scriptContent)) {
return false;
}
// "In modern user agents that support module scripts, the script element with
// the nomodule attribute will be ignored".
// "The nomodule attribute must not be specified on module scripts (and will
// be ignored if it is)."
if (scriptKind == ScriptKind::eClassic && scriptContent->IsHTMLElement() &&
scriptContent->AsElement()->HasAttr(nsGkAtoms::nomodule)) {
return false;
}
// Step 15. and later in the HTML5 spec
if (aElement->GetScriptExternal()) {
return ProcessExternalScript(aElement, scriptKind, aTypeAttr,
scriptContent);
}
return ProcessInlineScript(aElement, scriptKind);
}
static ParserMetadata GetParserMetadata(nsIScriptElement* aElement) {
return aElement->GetParserCreated() == mozilla::dom::NOT_FROM_PARSER
? ParserMetadata::NotParserInserted
: ParserMetadata::ParserInserted;
}
bool ScriptLoader::ProcessExternalScript(nsIScriptElement* aElement,
ScriptKind aScriptKind,
const nsAutoString& aTypeAttr,
nsIContent* aScriptContent) {
LOG(("ScriptLoader (%p): Process external script for element %p", this,
aElement));
// https://html.spec.whatwg.org/multipage/scripting.html#prepare-the-script-element
// Step 30.1. If el's type is "importmap", then queue an element task on the
// DOM manipulation task source given el to fire an event named error at el,
// and return.
if (aScriptKind == ScriptKind::eImportMap) {
NS_DispatchToCurrentThread(
NewRunnableMethod("nsIScriptElement::FireErrorEvent", aElement,
&nsIScriptElement::FireErrorEvent));
nsContentUtils::ReportToConsole(
nsIScriptError::warningFlag, "Script Loader"_ns, mDocument,
nsContentUtils::eDOM_PROPERTIES, "ImportMapExternalNotSupported");
return false;
}
nsCOMPtr<nsIURI> scriptURI = aElement->GetScriptURI();
if (!scriptURI) {
// Asynchronously report the failure to create a URI object
NS_DispatchToCurrentThread(
NewRunnableMethod("nsIScriptElement::FireErrorEvent", aElement,
&nsIScriptElement::FireErrorEvent));
return false;
}
nsAutoString nonce;
if (nsString* cspNonce = static_cast<nsString*>(
aScriptContent->GetProperty(nsGkAtoms::nonce))) {
nonce = *cspNonce;
}
SRIMetadata sriMetadata;
{
nsAutoString integrity;
aScriptContent->AsElement()->GetAttr(nsGkAtoms::integrity, integrity);
GetSRIMetadata(integrity, &sriMetadata);
}
RefPtr<ScriptLoadRequest> request =
LookupPreloadRequest(aElement, aScriptKind, sriMetadata);
if (request && NS_FAILED(CheckContentPolicy(mDocument, aElement, aTypeAttr,
nonce, request))) {
LOG(("ScriptLoader (%p): content policy check failed for preload", this));
// Probably plans have changed; even though the preload was allowed seems
// like the actual load is not; let's cancel the preload request.
request->Cancel();
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::RejectedByPolicy);
return false;
}
if (request && request->IsModuleRequest() &&
mModuleLoader->HasImportMapRegistered()) {
// We don't preload module scripts after seeing an import map but a script
// can dynamically insert an import map after preloading has happened.
request->Cancel();
request = nullptr;
}
if (request) {
// Use the preload request.
LOG(("ScriptLoadRequest (%p): Using preload request", request.get()));
// https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-module-script-tree
// Step 1. Disallow further import maps given settings object.
if (request->IsModuleRequest()) {
LOG(("ScriptLoadRequest (%p): Disallow further import maps.",
request.get()));
mModuleLoader->DisallowImportMaps();
}
// It's possible these attributes changed since we started the preload so
// update them here.
request->GetScriptLoadContext()->SetScriptMode(
aElement->GetScriptDeferred(), aElement->GetScriptAsync(), false);
// The request will be added to another list or set as
// mParserBlockingRequest below.
if (request->GetScriptLoadContext()->mInCompilingList) {
mOffThreadCompilingRequests.Remove(request);
request->GetScriptLoadContext()->mInCompilingList = false;
}
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::Used);
} else {
// No usable preload found.
nsCOMPtr<nsIPrincipal> principal =
aElement->GetScriptURITriggeringPrincipal();
if (!principal) {
principal = aScriptContent->NodePrincipal();
}
CORSMode ourCORSMode = aElement->GetCORSMode();
const FetchPriority fetchPriority = aElement->GetFetchPriority();
ReferrerPolicy referrerPolicy = GetReferrerPolicy(aElement);
ParserMetadata parserMetadata = GetParserMetadata(aElement);
request = CreateLoadRequest(aScriptKind, scriptURI, aElement, principal,
ourCORSMode, nonce,
FetchPriorityToRequestPriority(fetchPriority),
sriMetadata, referrerPolicy, parserMetadata);
request->GetScriptLoadContext()->mIsInline = false;
request->GetScriptLoadContext()->SetScriptMode(
aElement->GetScriptDeferred(), aElement->GetScriptAsync(), false);
// keep request->GetScriptLoadContext()->mScriptFromHead to false so we
// don't treat non preloaded scripts as blockers for full page load. See bug
// 792438.
LOG(("ScriptLoadRequest (%p): Created request for external script",
request.get()));
nsresult rv = StartLoad(request, Nothing());
if (NS_FAILED(rv)) {
ReportErrorToConsole(request, rv);
// Asynchronously report the load failure
nsCOMPtr<nsIRunnable> runnable =
NewRunnableMethod("nsIScriptElement::FireErrorEvent", aElement,
&nsIScriptElement::FireErrorEvent);
if (mDocument) {
mDocument->Dispatch(runnable.forget());
} else {
NS_DispatchToCurrentThread(runnable.forget());
}
return false;
}
}
// We should still be in loading stage of script unless we're loading a
// module or speculatively off-main-thread parsing a script.
NS_ASSERTION(SpeculativeOMTParsingEnabled() ||
!request->GetScriptLoadContext()->CompileStarted() ||
request->IsModuleRequest(),
"Request should not yet be in compiling stage.");
if (request->GetScriptLoadContext()->IsAsyncScript()) {
AddAsyncRequest(request);
if (request->IsFinished()) {
// The script is available already. Run it ASAP when the event
// loop gets a chance to spin.
// KVKV TODO: Instead of processing immediately, try off-thread-parsing
// it and only schedule a pending ProcessRequest if that fails.
ProcessPendingRequestsAsync();
}
return false;
}
if (!aElement->GetParserCreated()) {
// Violate the HTML5 spec in order to make LABjs and the "order" plug-in
// for RequireJS work with their Gecko-sniffed code path. See
// http://lists.w3.org/Archives/Public/public-html/2010Oct/0088.html
request->GetScriptLoadContext()->mIsNonAsyncScriptInserted = true;
mNonAsyncExternalScriptInsertedRequests.AppendElement(request);
if (request->IsFinished()) {
// The script is available already. Run it ASAP when the event
// loop gets a chance to spin.
ProcessPendingRequestsAsync();
}
return false;
}
// we now have a parser-inserted request that may or may not be still
// loading
if (request->GetScriptLoadContext()->IsDeferredScript()) {
// We don't want to run this yet.
// If we come here, the script is a parser-created script and it has
// the defer attribute but not the async attribute OR it is a module
// script without the async attribute. Since a
// a parser-inserted script is being run, we came here by the parser
// running the script, which means the parser is still alive and the
// parse is ongoing.
NS_ASSERTION(mDocument->GetCurrentContentSink() ||
aElement->GetParserCreated() == FROM_PARSER_XSLT,
"Non-XSLT Defer script on a document without an active "
"parser; bug 592366.");
AddDeferRequest(request);
return false;
}
if (aElement->GetParserCreated() == FROM_PARSER_XSLT) {
// Need to maintain order for XSLT-inserted scripts
NS_ASSERTION(!mParserBlockingRequest,
"Parser-blocking scripts and XSLT scripts in the same doc!");
request->GetScriptLoadContext()->mIsXSLT = true;
mXSLTRequests.AppendElement(request);
if (request->IsFinished()) {
// The script is available already. Run it ASAP when the event
// loop gets a chance to spin.
ProcessPendingRequestsAsync();
}
return true;
}
if (request->IsFinished() && ReadyToExecuteParserBlockingScripts()) {
// The request has already been loaded and there are no pending style
// sheets. If the script comes from the network stream, cheat for
// performance reasons and avoid a trip through the event loop.
if (aElement->GetParserCreated() == FROM_PARSER_NETWORK) {
return ProcessRequest(request) == NS_ERROR_HTMLPARSER_BLOCK;
}
// Otherwise, we've got a document.written script, make a trip through
// the event loop to hide the preload effects from the scripts on the
// Web page.
NS_ASSERTION(!mParserBlockingRequest,
"There can be only one parser-blocking script at a time");
NS_ASSERTION(mXSLTRequests.isEmpty(),
"Parser-blocking scripts and XSLT scripts in the same doc!");
mParserBlockingRequest = request;
ProcessPendingRequestsAsync();
return true;
}
// The script hasn't loaded yet or there's a style sheet blocking it.
// The script will be run when it loads or the style sheet loads.
NS_ASSERTION(!mParserBlockingRequest,
"There can be only one parser-blocking script at a time");
NS_ASSERTION(mXSLTRequests.isEmpty(),
"Parser-blocking scripts and XSLT scripts in the same doc!");
mParserBlockingRequest = request;
return true;
}
bool ScriptLoader::ProcessInlineScript(nsIScriptElement* aElement,
ScriptKind aScriptKind) {
// Is this document sandboxed without 'allow-scripts'?
if (mDocument->HasScriptsBlockedBySandbox()) {
return false;
}
nsCOMPtr<nsINode> node = do_QueryInterface(aElement);
nsAutoString nonce;
if (nsString* cspNonce =
static_cast<nsString*>(node->GetProperty(nsGkAtoms::nonce))) {
nonce = *cspNonce;
}
// Does CSP allow this inline script to run?
if (!CSPAllowsInlineScript(aElement, nonce, mDocument)) {
return false;
}
// Check if adding an import map script is allowed. If not, we bail out
// early to prevent creating a load request.
if (aScriptKind == ScriptKind::eImportMap) {
// https://html.spec.whatwg.org/multipage/scripting.html#prepare-the-script-element
// Step 31.2 type is "importmap":
// Step 1. If el's relevant global object's import maps allowed is false,
// then queue an element task on the DOM manipulation task source given el
// to fire an event named error at el, and return.
if (!mModuleLoader->IsImportMapAllowed()) {
NS_WARNING("ScriptLoader: import maps allowed is false.");
const char* msg = mModuleLoader->HasImportMapRegistered()
? "ImportMapNotAllowedMultiple"
: "ImportMapNotAllowedAfterModuleLoad";
nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
"Script Loader"_ns, mDocument,
nsContentUtils::eDOM_PROPERTIES, msg);
NS_DispatchToCurrentThread(
NewRunnableMethod("nsIScriptElement::FireErrorEvent", aElement,
&nsIScriptElement::FireErrorEvent));
return false;
}
}
// Inline classic scripts ignore their CORS mode and are always CORS_NONE.
CORSMode corsMode = CORS_NONE;
if (aScriptKind == ScriptKind::eModule) {
corsMode = aElement->GetCORSMode();
}
// <https://html.spec.whatwg.org/multipage/scripting.html#prepare-the-script-element>
// step 29 specifies to use the fetch priority. Presumably it has no effect
// for inline scripts.
const auto fetchPriority = aElement->GetFetchPriority();
ReferrerPolicy referrerPolicy = GetReferrerPolicy(aElement);
ParserMetadata parserMetadata = GetParserMetadata(aElement);
RefPtr<ScriptLoadRequest> request =
CreateLoadRequest(aScriptKind, mDocument->GetDocumentURI(), aElement,
mDocument->NodePrincipal(), corsMode, nonce,
FetchPriorityToRequestPriority(fetchPriority),
SRIMetadata(), // SRI doesn't apply
referrerPolicy, parserMetadata);
request->GetScriptLoadContext()->mIsInline = true;
request->GetScriptLoadContext()->mLineNo = aElement->GetScriptLineNumber();
request->GetScriptLoadContext()->mColumnNo =
aElement->GetScriptColumnNumber();
request->mFetchSourceOnly = true;
request->SetTextSource();
TRACE_FOR_TEST_BOOL(request->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_load_source");
CollectScriptTelemetry(request);
// Only the 'async' attribute is heeded on an inline module script and
// inline classic scripts ignore both these attributes.
MOZ_ASSERT(!aElement->GetScriptDeferred());
MOZ_ASSERT_IF(!request->IsModuleRequest(), !aElement->GetScriptAsync());
request->GetScriptLoadContext()->SetScriptMode(
false, aElement->GetScriptAsync(), false);
LOG(("ScriptLoadRequest (%p): Created request for inline script",
request.get()));
request->mBaseURL = mDocument->GetDocBaseURI();
if (request->IsModuleRequest()) {
// https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-inline-module-script-graph
// Step 1. Disallow further import maps given settings object.
mModuleLoader->DisallowImportMaps();
ModuleLoadRequest* modReq = request->AsModuleRequest();
if (aElement->GetParserCreated() != NOT_FROM_PARSER) {
if (aElement->GetScriptAsync()) {
AddAsyncRequest(modReq);
} else {
AddDeferRequest(modReq);
}
}
// This calls OnFetchComplete directly since there's no need to start
// fetching an inline script.
nsresult rv = modReq->OnFetchComplete(NS_OK);
if (NS_FAILED(rv)) {
ReportErrorToConsole(modReq, rv);
HandleLoadError(modReq, rv);
}
return false;
}
if (request->IsImportMapRequest()) {
// https://html.spec.whatwg.org/multipage/scripting.html#prepare-the-script-element
// Step 31.2 type is "importmap":
// Impl note: Step 1 is done above before creating a ScriptLoadRequest.
MOZ_ASSERT(mModuleLoader->IsImportMapAllowed());
// Step 2. Set el's relevant global object's import maps allowed to false.
mModuleLoader->DisallowImportMaps();
// Step 3. Let result be the result of creating an import map parse result
// given source text and base URL.
UniquePtr<ImportMap> importMap = mModuleLoader->ParseImportMap(request);
if (!importMap) {
// If parsing import maps fails, the exception will be reported in
// ModuleLoaderBase::ParseImportMap, and the registration of the import
// map will bail out early.
return false;
}
// TODO: Bug 1781758: Move RegisterImportMap into EvaluateScriptElement.
//
// https://html.spec.whatwg.org/multipage/scripting.html#execute-the-script-element
// The spec defines 'register an import map' should be done in
// 'execute the script element', because inside 'execute the script element'
// it will perform a 'preparation-time document check'.
// However, as import maps could be only inline scripts by now, the
// 'preparation-time document check' will never fail for import maps.
// So we simply call 'register an import map' here.
mModuleLoader->RegisterImportMap(std::move(importMap));
return false;
}
request->mState = ScriptLoadRequest::State::Ready;
if (aElement->GetParserCreated() == FROM_PARSER_XSLT &&
(!ReadyToExecuteParserBlockingScripts() || !mXSLTRequests.isEmpty())) {
// Need to maintain order for XSLT-inserted scripts
NS_ASSERTION(!mParserBlockingRequest,
"Parser-blocking scripts and XSLT scripts in the same doc!");
mXSLTRequests.AppendElement(request);
return true;
}
if (aElement->GetParserCreated() == NOT_FROM_PARSER) {
NS_ASSERTION(
!nsContentUtils::IsSafeToRunScript(),
"A script-inserted script is inserted without an update batch?");
RunScriptWhenSafe(request);
return false;
}
if (aElement->GetParserCreated() == FROM_PARSER_NETWORK &&
!ReadyToExecuteParserBlockingScripts()) {
NS_ASSERTION(!mParserBlockingRequest,
"There can be only one parser-blocking script at a time");
mParserBlockingRequest = request;
NS_ASSERTION(mXSLTRequests.isEmpty(),
"Parser-blocking scripts and XSLT scripts in the same doc!");
return true;
}
// We now have a document.written inline script or we have an inline script
// from the network but there is no style sheet that is blocking scripts.
// Don't check for style sheets blocking scripts in the document.write
// case to avoid style sheet network activity affecting when
// document.write returns. It's not really necessary to do this if
// there's no document.write currently on the call stack. However,
// this way matches IE more closely than checking if document.write
// is on the call stack.
NS_ASSERTION(nsContentUtils::IsSafeToRunScript(),
"Not safe to run a parser-inserted script?");
return ProcessRequest(request) == NS_ERROR_HTMLPARSER_BLOCK;
}
ScriptLoadRequest* ScriptLoader::LookupPreloadRequest(
nsIScriptElement* aElement, ScriptKind aScriptKind,
const SRIMetadata& aSRIMetadata) {
MOZ_ASSERT(aElement);
nsTArray<PreloadInfo>::index_type i =
mPreloads.IndexOf(aElement->GetScriptURI(), 0, PreloadURIComparator());
if (i == nsTArray<PreloadInfo>::NoIndex) {
return nullptr;
}
RefPtr<ScriptLoadRequest> request = mPreloads[i].mRequest;
if (aScriptKind != request->mKind) {
return nullptr;
}
// Found preloaded request. Note that a script-inserted script can steal a
// preload!
request->GetScriptLoadContext()->SetIsLoadRequest(aElement);
if (request->GetScriptLoadContext()->mWasCompiledOMT &&
!request->IsModuleRequest()) {
request->SetReady();
}
nsString preloadCharset(mPreloads[i].mCharset);
mPreloads.RemoveElementAt(i);
// Double-check that the charset the preload used is the same as the charset
// we have now.
nsAutoString elementCharset;
aElement->GetScriptCharset(elementCharset);
// Bug 1832361: charset and crossorigin attributes shouldn't affect matching
// of module scripts and modulepreload
if (!request->IsModuleRequest() &&
(!elementCharset.Equals(preloadCharset) ||
aElement->GetCORSMode() != request->CORSMode())) {
// Drop the preload.
request->Cancel();
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::RequestMismatch);
return nullptr;
}
if (!aSRIMetadata.CanTrustBeDelegatedTo(request->mIntegrity)) {
// Don't cancel link preload requests, we want to deliver onload according
// the result of the load, cancellation would unexpectedly lead to error
// notification.
if (!request->GetScriptLoadContext()->IsLinkPreloadScript()) {
request->Cancel();
}
return nullptr;
}
// Report any errors that we skipped while preloading.
ReportPreloadErrorsToConsole(request);
// This makes sure the pending preload (if exists) for this resource is
// properly marked as used and thus not notified in the console as unused.
request->GetScriptLoadContext()->NotifyUsage(mDocument);
// A used preload must no longer be found in the Document's hash table. Any
// <link preload> tag after the <script> tag will start a new request, that
// can be satisfied from a different cache, but not from the preload cache.
request->GetScriptLoadContext()->RemoveSelf(mDocument);
return request;
}
void ScriptLoader::GetSRIMetadata(const nsAString& aIntegrityAttr,
SRIMetadata* aMetadataOut) {
MOZ_ASSERT(aMetadataOut->IsEmpty());
if (aIntegrityAttr.IsEmpty()) {
return;
}
MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug,
("ScriptLoader::GetSRIMetadata, integrity=%s",
NS_ConvertUTF16toUTF8(aIntegrityAttr).get()));
nsAutoCString sourceUri;
if (mDocument->GetDocumentURI()) {
mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri);
}
SRICheck::IntegrityMetadata(aIntegrityAttr, sourceUri, mReporter,
aMetadataOut);
}
ReferrerPolicy ScriptLoader::GetReferrerPolicy(nsIScriptElement* aElement) {
ReferrerPolicy scriptReferrerPolicy = aElement->GetReferrerPolicy();
if (scriptReferrerPolicy != ReferrerPolicy::_empty) {
return scriptReferrerPolicy;
}
return mDocument->GetReferrerPolicy();
}
void ScriptLoader::CancelAndClearScriptLoadRequests() {
// Cancel all requests that have not been executed and remove them.
if (mParserBlockingRequest) {
mParserBlockingRequest->Cancel();
mParserBlockingRequest = nullptr;
}
mDeferRequests.CancelRequestsAndClear();
mLoadingAsyncRequests.CancelRequestsAndClear();
mLoadedAsyncRequests.CancelRequestsAndClear();
mNonAsyncExternalScriptInsertedRequests.CancelRequestsAndClear();
mXSLTRequests.CancelRequestsAndClear();
mOffThreadCompilingRequests.CancelRequestsAndClear();
if (mModuleLoader) {
mModuleLoader->CancelAndClearDynamicImports();
}
for (ModuleLoader* loader : mWebExtModuleLoaders) {
loader->CancelAndClearDynamicImports();
}
for (ModuleLoader* loader : mShadowRealmModuleLoaders) {
loader->CancelAndClearDynamicImports();
}
for (size_t i = 0; i < mPreloads.Length(); i++) {
mPreloads[i].mRequest->Cancel();
}
mPreloads.Clear();
}
nsresult ScriptLoader::CompileOffThreadOrProcessRequest(
ScriptLoadRequest* aRequest) {
NS_ASSERTION(nsContentUtils::IsSafeToRunScript(),
"Processing requests when running scripts is unsafe.");
if (!aRequest->GetScriptLoadContext()->mCompileOrDecodeTask &&
!aRequest->GetScriptLoadContext()->CompileStarted()) {
bool couldCompile = false;
nsresult rv = AttemptOffThreadScriptCompile(aRequest, &couldCompile);
if (NS_FAILED(rv)) {
HandleLoadError(aRequest, rv);
return rv;
}
if (couldCompile) {
return NS_OK;
}
}
return ProcessRequest(aRequest);
}
namespace {
class OffThreadCompilationCompleteTask : public Task {
public:
OffThreadCompilationCompleteTask(ScriptLoadRequest* aRequest,
ScriptLoader* aLoader)
: Task(Kind::MainThreadOnly, EventQueuePriority::Normal),
mRequest(aRequest),
mLoader(aLoader) {
MOZ_ASSERT(NS_IsMainThread());
}
void RecordStartTime() { mStartTime = TimeStamp::Now(); }
void RecordStopTime() { mStopTime = TimeStamp::Now(); }
#ifdef MOZ_COLLECTING_RUNNABLE_TELEMETRY
bool GetName(nsACString& aName) override {
aName.AssignLiteral("dom::OffThreadCompilationCompleteTask");
return true;
}
#endif
TaskResult Run() override {
MOZ_ASSERT(NS_IsMainThread());
RefPtr<ScriptLoadContext> context = mRequest->GetScriptLoadContext();
if (!context->mCompileOrDecodeTask) {
// Request has been cancelled by MaybeCancelOffThreadScript.
return TaskResult::Complete;
}
RecordStopTime();
if (profiler_is_active()) {
ProfilerString8View scriptSourceString;
if (mRequest->IsTextSource()) {
scriptSourceString = "ScriptCompileOffThread";
} else {
MOZ_ASSERT(mRequest->IsBytecode());
scriptSourceString = "BytecodeDecodeOffThread";
}
nsAutoCString profilerLabelString;
mRequest->GetScriptLoadContext()->GetProfilerLabel(profilerLabelString);
PROFILER_MARKER_TEXT(scriptSourceString, JS,
MarkerTiming::Interval(mStartTime, mStopTime),
profilerLabelString);
}
(void)mLoader->ProcessOffThreadRequest(mRequest);
mRequest = nullptr;
mLoader = nullptr;
return TaskResult::Complete;
}
private:
// NOTE:
// These fields are main-thread only, and this task shouldn't be freed off
// main thread.
//
// This is guaranteed by not having off-thread tasks which depends on this
// task, because otherwise the off-thread task's mDependencies can be the
// last reference, which results in freeing this task off main thread.
//
// If such task is added, these fields must be moved to separate storage.
RefPtr<ScriptLoadRequest> mRequest;
RefPtr<ScriptLoader> mLoader;
TimeStamp mStartTime;
TimeStamp mStopTime;
};
} /* anonymous namespace */
// TODO: This uses the same heuristics and the same threshold as the
// JS::CanCompileOffThread / JS::CanDecodeOffThread APIs, but the
// heuristics needs to be updated to reflect the change regarding the
// Stencil API, and also the thread management on the consumer side
// (bug 1846160).
static constexpr size_t OffThreadMinimumTextLength = 5 * 1000;
static constexpr size_t OffThreadMinimumBytecodeLength = 5 * 1000;
nsresult ScriptLoader::AttemptOffThreadScriptCompile(
ScriptLoadRequest* aRequest, bool* aCouldCompileOut) {
// If speculative parsing is enabled, the request may not be ready to run if
// the element is not yet available.
MOZ_ASSERT_IF(!SpeculativeOMTParsingEnabled() && !aRequest->IsModuleRequest(),
aRequest->IsFinished());
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mWasCompiledOMT);
MOZ_ASSERT(aCouldCompileOut && !*aCouldCompileOut);
// Don't off-thread compile inline scripts.
if (aRequest->GetScriptLoadContext()->mIsInline) {
return NS_OK;
}
nsCOMPtr<nsIGlobalObject> globalObject = GetGlobalForRequest(aRequest);
if (!globalObject) {
return NS_ERROR_FAILURE;
}
AutoJSAPI jsapi;
if (!jsapi.Init(globalObject)) {
return NS_ERROR_FAILURE;
}
JSContext* cx = jsapi.cx();
JS::CompileOptions options(cx);
// Introduction script will actually be computed and set when the script is
// collected from offthread
JS::Rooted<JSScript*> dummyIntroductionScript(cx);
nsresult rv = FillCompileOptionsForRequest(cx, aRequest, &options,
&dummyIntroductionScript);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
if (aRequest->IsTextSource()) {
if (!StaticPrefs::javascript_options_parallel_parsing() ||
aRequest->ScriptTextLength() < OffThreadMinimumTextLength) {
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_main_thread_compile");
return NS_OK;
}
} else {
MOZ_ASSERT(aRequest->IsBytecode());
size_t length =
aRequest->mScriptBytecode.length() - aRequest->mBytecodeOffset;
if (!StaticPrefs::javascript_options_parallel_parsing() ||
length < OffThreadMinimumBytecodeLength) {
return NS_OK;
}
}
RefPtr<CompileOrDecodeTask> compileOrDecodeTask;
rv = CreateOffThreadTask(cx, aRequest, options,
getter_AddRefs(compileOrDecodeTask));
NS_ENSURE_SUCCESS(rv, rv);
RefPtr<OffThreadCompilationCompleteTask> completeTask =
new OffThreadCompilationCompleteTask(aRequest, this);
completeTask->RecordStartTime();
aRequest->GetScriptLoadContext()->mCompileOrDecodeTask = compileOrDecodeTask;
completeTask->AddDependency(compileOrDecodeTask);
TaskController::Get()->AddTask(compileOrDecodeTask.forget());
TaskController::Get()->AddTask(completeTask.forget());
aRequest->GetScriptLoadContext()->BlockOnload(mDocument);
// Once the compilation is finished, the completeTask will be run on
// the main thread to call ScriptLoader::ProcessOffThreadRequest for the
// request.
aRequest->mState = ScriptLoadRequest::State::Compiling;
// Requests that are not tracked elsewhere are added to a list while they are
// being compiled off-thread, so we can cancel the compilation later if
// necessary.
//
// Non-top-level modules not tracked because these are cancelled from their
// importing module.
if (aRequest->IsTopLevel() && !aRequest->isInList()) {
mOffThreadCompilingRequests.AppendElement(aRequest);
aRequest->GetScriptLoadContext()->mInCompilingList = true;
}
*aCouldCompileOut = true;
return NS_OK;
}
CompileOrDecodeTask::CompileOrDecodeTask()
: Task(Kind::OffMainThreadOnly, EventQueuePriority::Normal),
mMutex("CompileOrDecodeTask"),
mOptions(JS::OwningCompileOptions::ForFrontendContext()) {}
CompileOrDecodeTask::~CompileOrDecodeTask() {
if (mFrontendContext) {
JS::DestroyFrontendContext(mFrontendContext);
mFrontendContext = nullptr;
}
}
nsresult CompileOrDecodeTask::InitFrontendContext() {
mFrontendContext = JS::NewFrontendContext();
if (!mFrontendContext) {
mIsCancelled = true;
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
void CompileOrDecodeTask::DidRunTask(const MutexAutoLock& aProofOfLock,
RefPtr<JS::Stencil>&& aStencil) {
if (aStencil) {
if (!JS::PrepareForInstantiate(mFrontendContext, *aStencil,
mInstantiationStorage)) {
aStencil = nullptr;
}
}
mStencil = std::move(aStencil);
}
already_AddRefed<JS::Stencil> CompileOrDecodeTask::StealResult(
JSContext* aCx, JS::InstantiationStorage* aInstantiationStorage) {
JS::FrontendContext* fc = mFrontendContext;
mFrontendContext = nullptr;
auto destroyFrontendContext =
mozilla::MakeScopeExit([&]() { JS::DestroyFrontendContext(fc); });
MOZ_ASSERT(fc);
if (JS::HadFrontendErrors(fc)) {
(void)JS::ConvertFrontendErrorsToRuntimeErrors(aCx, fc, mOptions);
return nullptr;
}
if (!mStencil && JS::IsTranscodeFailureResult(mResult)) {
// Decode failure with bad content isn't reported as error.
JS_ReportErrorASCII(aCx, "failed to decode cache");
return nullptr;
}
// Report warnings.
if (!JS::ConvertFrontendErrorsToRuntimeErrors(aCx, fc, mOptions)) {
return nullptr;
}
MOZ_ASSERT(mStencil,
"If this task is cancelled, StealResult shouldn't be called");
// This task is started and finished successfully.
*aInstantiationStorage = std::move(mInstantiationStorage);
return mStencil.forget();
}
void CompileOrDecodeTask::Cancel() {
MOZ_ASSERT(NS_IsMainThread());
MutexAutoLock lock(mMutex);
mIsCancelled = true;
}
enum class CompilationTarget { Script, Module };
template <CompilationTarget target>
class ScriptOrModuleCompileTask final : public CompileOrDecodeTask {
public:
explicit ScriptOrModuleCompileTask(
ScriptLoader::MaybeSourceText&& aMaybeSource)
: CompileOrDecodeTask(), mMaybeSource(std::move(aMaybeSource)) {}
nsresult Init(JS::CompileOptions& aOptions) {
nsresult rv = InitFrontendContext();
NS_ENSURE_SUCCESS(rv, rv);
if (!mOptions.copy(mFrontendContext, aOptions)) {
mIsCancelled = true;
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
TaskResult Run() override {
MutexAutoLock lock(mMutex);
if (IsCancelled(lock)) {
return TaskResult::Complete;
}
RefPtr<JS::Stencil> stencil = Compile();
DidRunTask(lock, std::move(stencil));
return TaskResult::Complete;
}
private:
already_AddRefed<JS::Stencil> Compile() {
size_t stackSize = TaskController::GetThreadStackSize();
JS::SetNativeStackQuota(mFrontendContext,
JS::ThreadStackQuotaForSize(stackSize));
JS::CompilationStorage compileStorage;
auto compile = [&](auto& source) {
if constexpr (target == CompilationTarget::Script) {
return JS::CompileGlobalScriptToStencil(mFrontendContext, mOptions,
source, compileStorage);
}
return JS::CompileModuleScriptToStencil(mFrontendContext, mOptions,
source, compileStorage);
};
return mMaybeSource.mapNonEmpty(compile);
}
public:
#ifdef MOZ_COLLECTING_RUNNABLE_TELEMETRY
bool GetName(nsACString& aName) override {
if constexpr (target == CompilationTarget::Script) {
aName.AssignLiteral("ScriptCompileTask");
} else {
aName.AssignLiteral("ModuleCompileTask");
}
return true;
}
#endif
private:
ScriptLoader::MaybeSourceText mMaybeSource;
};
using ScriptCompileTask =
class ScriptOrModuleCompileTask<CompilationTarget::Script>;
using ModuleCompileTask =
class ScriptOrModuleCompileTask<CompilationTarget::Module>;
class ScriptDecodeTask final : public CompileOrDecodeTask {
public:
explicit ScriptDecodeTask(const JS::TranscodeRange& aRange)
: mRange(aRange) {}
nsresult Init(JS::DecodeOptions& aOptions) {
nsresult rv = InitFrontendContext();
NS_ENSURE_SUCCESS(rv, rv);
if (!mDecodeOptions.copy(mFrontendContext, aOptions)) {
mIsCancelled = true;
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
TaskResult Run() override {
MutexAutoLock lock(mMutex);
if (IsCancelled(lock)) {
return TaskResult::Complete;
}
RefPtr<JS::Stencil> stencil = Decode();
JS::OwningCompileOptions compileOptions(
(JS::OwningCompileOptions::ForFrontendContext()));
mOptions.steal(std::move(mDecodeOptions));
DidRunTask(lock, std::move(stencil));
return TaskResult::Complete;
}
private:
already_AddRefed<JS::Stencil> Decode() {
// NOTE: JS::DecodeStencil doesn't need the stack quota.
JS::CompilationStorage compileStorage;
RefPtr<JS::Stencil> stencil;
mResult = JS::DecodeStencil(mFrontendContext, mDecodeOptions, mRange,
getter_AddRefs(stencil));
return stencil.forget();
}
public:
#ifdef MOZ_COLLECTING_RUNNABLE_TELEMETRY
bool GetName(nsACString& aName) override {
aName.AssignLiteral("ScriptDecodeTask");
return true;
}
#endif
private:
JS::OwningDecodeOptions mDecodeOptions;
JS::TranscodeRange mRange;
};
nsresult ScriptLoader::CreateOffThreadTask(
JSContext* aCx, ScriptLoadRequest* aRequest, JS::CompileOptions& aOptions,
CompileOrDecodeTask** aCompileOrDecodeTask) {
if (aRequest->IsBytecode()) {
JS::DecodeOptions decodeOptions(aOptions);
JS::TranscodeRange range(
aRequest->mScriptBytecode.begin() + aRequest->mBytecodeOffset,
aRequest->mScriptBytecode.length() - aRequest->mBytecodeOffset);
RefPtr<ScriptDecodeTask> decodeTask = new ScriptDecodeTask(range);
nsresult rv = decodeTask->Init(decodeOptions);
NS_ENSURE_SUCCESS(rv, rv);
decodeTask.forget(aCompileOrDecodeTask);
return NS_OK;
}
MaybeSourceText maybeSource;
nsresult rv = aRequest->GetScriptSource(aCx, &maybeSource);
NS_ENSURE_SUCCESS(rv, rv);
if (ShouldApplyDelazifyStrategy(aRequest)) {
ApplyDelazifyStrategy(&aOptions);
mTotalFullParseSize +=
aRequest->ScriptTextLength() > 0
? static_cast<uint32_t>(aRequest->ScriptTextLength())
: 0;
LOG(
("ScriptLoadRequest (%p): non-on-demand-only (omt) Parsing Enabled "
"for url=%s mTotalFullParseSize=%u",
aRequest, aRequest->mURI->GetSpecOrDefault().get(),
mTotalFullParseSize));
}
if (aRequest->IsModuleRequest()) {
RefPtr<ModuleCompileTask> compileTask =
new ModuleCompileTask(std::move(maybeSource));
rv = compileTask->Init(aOptions);
NS_ENSURE_SUCCESS(rv, rv);
compileTask.forget(aCompileOrDecodeTask);
return NS_OK;
}
if (StaticPrefs::dom_expose_test_interfaces()) {
switch (aOptions.eagerDelazificationStrategy()) {
case JS::DelazificationOption::OnDemandOnly:
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"delazification_on_demand_only");
break;
case JS::DelazificationOption::CheckConcurrentWithOnDemand:
case JS::DelazificationOption::ConcurrentDepthFirst:
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"delazification_concurrent_depth_first");
break;
case JS::DelazificationOption::ConcurrentLargeFirst:
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"delazification_concurrent_large_first");
break;
case JS::DelazificationOption::ParseEverythingEagerly:
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"delazification_parse_everything_eagerly");
break;
}
}
RefPtr<ScriptCompileTask> compileTask =
new ScriptCompileTask(std::move(maybeSource));
rv = compileTask->Init(aOptions);
NS_ENSURE_SUCCESS(rv, rv);
compileTask.forget(aCompileOrDecodeTask);
return NS_OK;
}
nsresult ScriptLoader::ProcessOffThreadRequest(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->IsCompiling());
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mWasCompiledOMT);
if (aRequest->IsCanceled()) {
return NS_OK;
}
aRequest->GetScriptLoadContext()->mWasCompiledOMT = true;
if (aRequest->GetScriptLoadContext()->mInCompilingList) {
mOffThreadCompilingRequests.Remove(aRequest);
aRequest->GetScriptLoadContext()->mInCompilingList = false;
}
if (aRequest->IsModuleRequest()) {
MOZ_ASSERT(aRequest->GetScriptLoadContext()->mCompileOrDecodeTask);
ModuleLoadRequest* request = aRequest->AsModuleRequest();
return request->OnFetchComplete(NS_OK);
}
// Element may not be ready yet if speculatively compiling, so process the
// request in ProcessPendingRequests when it is available.
MOZ_ASSERT_IF(!SpeculativeOMTParsingEnabled(),
aRequest->GetScriptLoadContext()->GetScriptElement());
if (!aRequest->GetScriptLoadContext()->GetScriptElement()) {
// Unblock onload here in case this request never gets executed.
aRequest->GetScriptLoadContext()->MaybeUnblockOnload();
return NS_OK;
}
aRequest->SetReady();
if (aRequest == mParserBlockingRequest) {
if (!ReadyToExecuteParserBlockingScripts()) {
// If not ready to execute scripts, schedule an async call to
// ProcessPendingRequests to handle it.
ProcessPendingRequestsAsync();
return NS_OK;
}
// Same logic as in top of ProcessPendingRequests.
mParserBlockingRequest = nullptr;
UnblockParser(aRequest);
ProcessRequest(aRequest);
ContinueParserAsync(aRequest);
return NS_OK;
}
// Async scripts and blocking scripts can be executed right away.
if ((aRequest->GetScriptLoadContext()->IsAsyncScript() ||
aRequest->GetScriptLoadContext()->IsBlockingScript()) &&
!aRequest->isInList()) {
return ProcessRequest(aRequest);
}
// Process other scripts in the proper order.
ProcessPendingRequests();
return NS_OK;
}
nsresult ScriptLoader::ProcessRequest(ScriptLoadRequest* aRequest) {
LOG(("ScriptLoadRequest (%p): Process request", aRequest));
NS_ASSERTION(nsContentUtils::IsSafeToRunScript(),
"Processing requests when running scripts is unsafe.");
NS_ASSERTION(aRequest->IsFinished(),
"Processing a request that is not ready to run.");
NS_ENSURE_ARG(aRequest);
auto unblockOnload = MakeScopeExit(
[&] { aRequest->GetScriptLoadContext()->MaybeUnblockOnload(); });
if (aRequest->IsModuleRequest()) {
ModuleLoadRequest* request = aRequest->AsModuleRequest();
if (request->IsDynamicImport()) {
request->ProcessDynamicImport();
return NS_OK;
}
if (request->mModuleScript) {
if (!request->InstantiateModuleGraph()) {
request->mModuleScript = nullptr;
}
}
if (!request->mModuleScript) {
// There was an error fetching a module script. Nothing to do here.
LOG(("ScriptLoadRequest (%p): Error loading request, firing error",
aRequest));
FireScriptAvailable(NS_ERROR_FAILURE, aRequest);
return NS_OK;
}
}
nsCOMPtr<nsINode> scriptElem =
do_QueryInterface(aRequest->GetScriptLoadContext()->GetScriptElement());
nsCOMPtr<Document> doc;
if (!aRequest->GetScriptLoadContext()->mIsInline ||
aRequest->IsModuleRequest()) {
doc = scriptElem->OwnerDoc();
}
nsCOMPtr<nsIScriptElement> oldParserInsertedScript;
uint32_t parserCreated = aRequest->GetScriptLoadContext()->GetParserCreated();
if (parserCreated) {
oldParserInsertedScript = mCurrentParserInsertedScript;
mCurrentParserInsertedScript =
aRequest->GetScriptLoadContext()->GetScriptElement();
}
aRequest->GetScriptLoadContext()->GetScriptElement()->BeginEvaluating();
FireScriptAvailable(NS_OK, aRequest);
// The window may have gone away by this point, in which case there's no point
// in trying to run the script.
{
// Try to perform a microtask checkpoint
nsAutoMicroTask mt;
}
nsPIDOMWindowInner* pwin = mDocument->GetInnerWindow();
bool runScript = !!pwin;
if (runScript) {
nsContentUtils::DispatchTrustedEvent(
scriptElem->OwnerDoc(), scriptElem, u"beforescriptexecute"_ns,
CanBubble::eYes, Cancelable::eYes, &runScript);
}
// Inner window could have gone away after firing beforescriptexecute
pwin = mDocument->GetInnerWindow();
if (!pwin) {
runScript = false;
}
nsresult rv = NS_OK;
if (runScript) {
if (doc) {
doc->IncrementIgnoreDestructiveWritesCounter();
}
rv = EvaluateScriptElement(aRequest);
if (doc) {
doc->DecrementIgnoreDestructiveWritesCounter();
}
nsContentUtils::DispatchTrustedEvent(scriptElem->OwnerDoc(), scriptElem,
u"afterscriptexecute"_ns,
CanBubble::eYes, Cancelable::eNo);
}
FireScriptEvaluated(rv, aRequest);
aRequest->GetScriptLoadContext()->GetScriptElement()->EndEvaluating();
if (parserCreated) {
mCurrentParserInsertedScript = oldParserInsertedScript;
}
if (aRequest->GetScriptLoadContext()->mCompileOrDecodeTask) {
// The request was parsed off-main-thread, but the result of the off
// thread parse was not actually needed to process the request
// (disappearing window, some other error, ...). Finish the
// request to avoid leaks.
MOZ_ASSERT(!aRequest->IsModuleRequest());
aRequest->GetScriptLoadContext()->MaybeCancelOffThreadScript();
}
// Free any source data, but keep the bytecode content as we might have to
// save it later.
aRequest->ClearScriptSource();
if (aRequest->IsBytecode()) {
// We received bytecode as input, thus we were decoding, and we will not be
// encoding the bytecode once more. We can safely clear the content of this
// buffer.
aRequest->mScriptBytecode.clearAndFree();
}
return rv;
}
void ScriptLoader::FireScriptAvailable(nsresult aResult,
ScriptLoadRequest* aRequest) {
for (int32_t i = 0; i < mObservers.Count(); i++) {
nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i];
obs->ScriptAvailable(
aResult, aRequest->GetScriptLoadContext()->GetScriptElement(),
aRequest->GetScriptLoadContext()->mIsInline, aRequest->mURI,
aRequest->GetScriptLoadContext()->mLineNo);
}
bool isInlineClassicScript = aRequest->GetScriptLoadContext()->mIsInline &&
!aRequest->IsModuleRequest();
RefPtr<nsIScriptElement> scriptElement =
aRequest->GetScriptLoadContext()->GetScriptElement();
scriptElement->ScriptAvailable(aResult, scriptElement, isInlineClassicScript,
aRequest->mURI,
aRequest->GetScriptLoadContext()->mLineNo);
}
// TODO: Convert this to MOZ_CAN_RUN_SCRIPT (bug 1415230)
MOZ_CAN_RUN_SCRIPT_BOUNDARY void ScriptLoader::FireScriptEvaluated(
nsresult aResult, ScriptLoadRequest* aRequest) {
for (int32_t i = 0; i < mObservers.Count(); i++) {
nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i];
RefPtr<nsIScriptElement> scriptElement =
aRequest->GetScriptLoadContext()->GetScriptElement();
obs->ScriptEvaluated(aResult, scriptElement,
aRequest->GetScriptLoadContext()->mIsInline);
}
RefPtr<nsIScriptElement> scriptElement =
aRequest->GetScriptLoadContext()->GetScriptElement();
scriptElement->ScriptEvaluated(aResult, scriptElement,
aRequest->GetScriptLoadContext()->mIsInline);
}
already_AddRefed<nsIGlobalObject> ScriptLoader::GetGlobalForRequest(
ScriptLoadRequest* aRequest) {
if (aRequest->IsModuleRequest()) {
ModuleLoader* loader =
ModuleLoader::From(aRequest->AsModuleRequest()->mLoader);
nsCOMPtr<nsIGlobalObject> global = loader->GetGlobalObject();
return global.forget();
}
return GetScriptGlobalObject();
}
already_AddRefed<nsIScriptGlobalObject> ScriptLoader::GetScriptGlobalObject() {
if (!mDocument) {
return nullptr;
}
nsPIDOMWindowInner* pwin = mDocument->GetInnerWindow();
if (!pwin) {
return nullptr;
}
nsCOMPtr<nsIScriptGlobalObject> globalObject = do_QueryInterface(pwin);
NS_ASSERTION(globalObject, "windows must be global objects");
// and make sure we are setup for this type of script.
nsresult rv = globalObject->EnsureScriptEnvironment();
if (NS_FAILED(rv)) {
return nullptr;
}
return globalObject.forget();
}
nsresult ScriptLoader::FillCompileOptionsForRequest(
JSContext* aCx, ScriptLoadRequest* aRequest, JS::CompileOptions* aOptions,
JS::MutableHandle<JSScript*> aIntroductionScript) {
// It's very important to use aRequest->mURI, not the final URI of the channel
// aRequest ended up getting script data from, as the script filename.
nsresult rv = aRequest->mURI->GetSpec(aRequest->mURL);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
if (mDocument) {
mDocument->NoteScriptTrackingStatus(
aRequest->mURL, aRequest->GetScriptLoadContext()->IsTracking());
}
const char* introductionType;
if (aRequest->IsModuleRequest() &&
!aRequest->AsModuleRequest()->IsTopLevel()) {
introductionType = "importedModule";
} else if (!aRequest->GetScriptLoadContext()->mIsInline) {
introductionType = "srcScript";
} else if (aRequest->GetScriptLoadContext()->GetParserCreated() ==
FROM_PARSER_NETWORK) {
introductionType = "inlineScript";
} else {
introductionType = "injectedScript";
}
aOptions->setIntroductionInfoToCaller(aCx, introductionType,
aIntroductionScript);
aOptions->setFileAndLine(aRequest->mURL.get(),
aRequest->GetScriptLoadContext()->mLineNo);
// The column is only relevant for inline scripts in order for SpiderMonkey to
// properly compute offsets relatively to the script position within the HTML
// file. injectedScript are not concerned and are always considered to start
// at column 0.
if (aRequest->GetScriptLoadContext()->mIsInline &&
aRequest->GetScriptLoadContext()->GetParserCreated() ==
FROM_PARSER_NETWORK) {
aOptions->setColumn(aRequest->GetScriptLoadContext()->mColumnNo);
}
aOptions->setIsRunOnce(true);
aOptions->setNoScriptRval(true);
if (aRequest->mSourceMapURL) {
aOptions->setSourceMapURL(aRequest->mSourceMapURL->get());
}
if (aRequest->mOriginPrincipal) {
nsCOMPtr<nsIGlobalObject> globalObject = GetGlobalForRequest(aRequest);
nsIPrincipal* scriptPrin = globalObject->PrincipalOrNull();
MOZ_ASSERT(scriptPrin);
bool subsumes = scriptPrin->Subsumes(aRequest->mOriginPrincipal);
aOptions->setMutedErrors(!subsumes);
}
if (aRequest->IsModuleRequest()) {
aOptions->setHideScriptFromDebugger(true);
}
aOptions->setDeferDebugMetadata(true);
aOptions->borrowBuffer = true;
return NS_OK;
}
/* static */
bool ScriptLoader::ShouldCacheBytecode(ScriptLoadRequest* aRequest) {
using mozilla::TimeDuration;
using mozilla::TimeStamp;
// We need the nsICacheInfoChannel to exist to be able to open the alternate
// data output stream. This pointer would only be non-null if the bytecode was
// activated at the time the channel got created in StartLoad.
if (!aRequest->mCacheInfo) {
LOG(("ScriptLoadRequest (%p): Cannot cache anything (cacheInfo = %p)",
aRequest, aRequest->mCacheInfo.get()));
return false;
}
// Look at the preference to know which strategy (parameters) should be used
// when the bytecode cache is enabled.
int32_t strategy = StaticPrefs::dom_script_loader_bytecode_cache_strategy();
// List of parameters used by the strategies.
bool hasSourceLengthMin = false;
bool hasFetchCountMin = false;
size_t sourceLengthMin = 100;
uint32_t fetchCountMin = 4;
LOG(("ScriptLoadRequest (%p): Bytecode-cache: strategy = %d.", aRequest,
strategy));
switch (strategy) {
case -2: {
// Reader mode, keep requesting alternate data but no longer save it.
LOG(("ScriptLoadRequest (%p): Bytecode-cache: Encoding disabled.",
aRequest));
return false;
}
case -1: {
// Eager mode, skip heuristics!
hasSourceLengthMin = false;
hasFetchCountMin = false;
break;
}
default:
case 0: {
hasSourceLengthMin = true;
hasFetchCountMin = true;
sourceLengthMin = 1024;
// If we were to optimize only for speed, without considering the impact
// on memory, we should set this threshold to 2. (Bug 900784 comment 120)
fetchCountMin = 4;
break;
}
}
// If the script is too small/large, do not attempt at creating a bytecode
// cache for this script, as the overhead of parsing it might not be worth the
// effort.
if (hasSourceLengthMin) {
size_t sourceLength;
size_t minLength;
MOZ_ASSERT(aRequest->IsTextSource());
sourceLength = aRequest->mScriptTextLength;
minLength = sourceLengthMin;
if (sourceLength < minLength) {
LOG(("ScriptLoadRequest (%p): Bytecode-cache: Script is too small.",
aRequest));
return false;
}
}
// Check that we loaded the cache entry a few times before attempting any
// bytecode-cache optimization, such that we do not waste time on entry which
// are going to be dropped soon.
if (hasFetchCountMin) {
uint32_t fetchCount = 0;
if (NS_FAILED(aRequest->mCacheInfo->GetCacheTokenFetchCount(&fetchCount))) {
LOG(("ScriptLoadRequest (%p): Bytecode-cache: Cannot get fetchCount.",
aRequest));
return false;
}
LOG(("ScriptLoadRequest (%p): Bytecode-cache: fetchCount = %d.", aRequest,
fetchCount));
if (fetchCount < fetchCountMin) {
return false;
}
}
LOG(("ScriptLoadRequest (%p): Bytecode-cache: Trigger encoding.", aRequest));
return true;
}
class MOZ_RAII AutoSetProcessingScriptTag {
nsCOMPtr<nsIScriptContext> mContext;
bool mOldTag;
public:
explicit AutoSetProcessingScriptTag(nsIScriptContext* aContext)
: mContext(aContext), mOldTag(mContext->GetProcessingScriptTag()) {
mContext->SetProcessingScriptTag(true);
}
~AutoSetProcessingScriptTag() { mContext->SetProcessingScriptTag(mOldTag); }
};
static nsresult ExecuteCompiledScript(JSContext* aCx, JSExecutionContext& aExec,
ClassicScript* aLoaderScript) {
JS::Rooted<JSScript*> script(aCx, aExec.GetScript());
if (!script) {
// Compilation succeeds without producing a script if scripting is
// disabled for the global.
return NS_OK;
}
if (JS::GetScriptPrivate(script).isUndefined()) {
aLoaderScript->AssociateWithScript(script);
}
return aExec.ExecScript();
}
nsresult ScriptLoader::EvaluateScriptElement(ScriptLoadRequest* aRequest) {
using namespace mozilla::Telemetry;
MOZ_ASSERT(aRequest->IsFinished());
// We need a document to evaluate scripts.
if (!mDocument) {
return NS_ERROR_FAILURE;
}
nsCOMPtr<nsIContent> scriptContent(
do_QueryInterface(aRequest->GetScriptLoadContext()->GetScriptElement()));
MOZ_ASSERT(scriptContent);
Document* ownerDoc = scriptContent->OwnerDoc();
if (ownerDoc != mDocument) {
// Willful violation of HTML5 as of 2010-12-01
return NS_ERROR_FAILURE;
}
nsCOMPtr<nsIGlobalObject> globalObject;
nsCOMPtr<nsIScriptContext> context;
if (!IsWebExtensionRequest(aRequest)) {
// Otherwise we have to ensure that there is a nsIScriptContext.
nsCOMPtr<nsIScriptGlobalObject> scriptGlobal = GetScriptGlobalObject();
if (!scriptGlobal) {
return NS_ERROR_FAILURE;
}
MOZ_ASSERT_IF(
aRequest->IsModuleRequest(),
aRequest->AsModuleRequest()->GetGlobalObject() == scriptGlobal);
// Make sure context is a strong reference since we access it after
// we've executed a script, which may cause all other references to
// the context to go away.
context = scriptGlobal->GetScriptContext();
if (!context) {
return NS_ERROR_FAILURE;
}
globalObject = scriptGlobal;
}
// Update our current script.
// This must be destroyed after destroying nsAutoMicroTask, see:
// https://bugzilla.mozilla.org/show_bug.cgi?id=1620505#c4
nsIScriptElement* currentScript =
aRequest->IsModuleRequest()
? nullptr
: aRequest->GetScriptLoadContext()->GetScriptElement();
AutoCurrentScriptUpdater scriptUpdater(this, currentScript);
Maybe<AutoSetProcessingScriptTag> setProcessingScriptTag;
if (context) {
setProcessingScriptTag.emplace(context);
}
// https://wicg.github.io/import-maps/#integration-script-type
// Switch on the script's type for scriptElement:
// "importmap"
// Assert: Never reached.
MOZ_ASSERT(!aRequest->IsImportMapRequest());
if (aRequest->IsModuleRequest()) {
return aRequest->AsModuleRequest()->EvaluateModule();
}
return EvaluateScript(globalObject, aRequest);
}
nsresult ScriptLoader::CompileOrDecodeClassicScript(
JSContext* aCx, JSExecutionContext& aExec, ScriptLoadRequest* aRequest) {
nsAutoCString profilerLabelString;
aRequest->GetScriptLoadContext()->GetProfilerLabel(profilerLabelString);
nsresult rv;
if (aRequest->IsBytecode()) {
if (aRequest->GetScriptLoadContext()->mCompileOrDecodeTask) {
LOG(("ScriptLoadRequest (%p): Decode Bytecode & instantiate and Execute",
aRequest));
rv = aExec.JoinOffThread(aRequest->GetScriptLoadContext());
} else {
LOG(("ScriptLoadRequest (%p): Decode Bytecode and Execute", aRequest));
AUTO_PROFILER_MARKER_TEXT("BytecodeDecodeMainThread", JS,
MarkerInnerWindowIdFromJSContext(aCx),
profilerLabelString);
rv = aExec.Decode(aRequest->mScriptBytecode, aRequest->mBytecodeOffset);
}
// We do not expect to be saving anything when we already have some
// bytecode.
MOZ_ASSERT(!aRequest->mCacheInfo);
return rv;
}
MOZ_ASSERT(aRequest->IsSource());
bool encodeBytecode = ShouldCacheBytecode(aRequest);
aExec.SetEncodeBytecode(encodeBytecode);
if (aRequest->GetScriptLoadContext()->mCompileOrDecodeTask) {
// Off-main-thread parsing.
LOG(
("ScriptLoadRequest (%p): instantiate off-thread result and "
"Execute",
aRequest));
MOZ_ASSERT(aRequest->IsTextSource());
rv = aExec.JoinOffThread(aRequest->GetScriptLoadContext());
} else {
// Main thread parsing (inline and small scripts)
LOG(("ScriptLoadRequest (%p): Compile And Exec", aRequest));
MOZ_ASSERT(aRequest->IsTextSource());
MaybeSourceText maybeSource;
rv = aRequest->GetScriptSource(aCx, &maybeSource);
if (NS_SUCCEEDED(rv)) {
AUTO_PROFILER_MARKER_TEXT("ScriptCompileMainThread", JS,
MarkerInnerWindowIdFromJSContext(aCx),
profilerLabelString);
auto compile = [&](auto& source) { return aExec.Compile(source); };
MOZ_ASSERT(!maybeSource.empty());
TimeStamp startTime = TimeStamp::Now();
rv = maybeSource.mapNonEmpty(compile);
mMainThreadParseTime += TimeStamp::Now() - startTime;
}
}
return rv;
}
/* static */
nsCString& ScriptLoader::BytecodeMimeTypeFor(ScriptLoadRequest* aRequest) {
if (aRequest->IsModuleRequest()) {
return nsContentUtils::JSModuleBytecodeMimeType();
}
return nsContentUtils::JSScriptBytecodeMimeType();
}
void ScriptLoader::MaybePrepareForBytecodeEncodingBeforeExecute(
ScriptLoadRequest* aRequest, JS::Handle<JSScript*> aScript) {
if (!ShouldCacheBytecode(aRequest)) {
return;
}
aRequest->MarkForBytecodeEncoding(aScript);
}
nsresult ScriptLoader::MaybePrepareForBytecodeEncodingAfterExecute(
ScriptLoadRequest* aRequest, nsresult aRv) {
if (aRequest->IsMarkedForBytecodeEncoding()) {
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_encode");
// NOTE: This assertion will fail once we start encoding more data after the
// first encode.
MOZ_ASSERT(aRequest->mBytecodeOffset == aRequest->mScriptBytecode.length());
RegisterForBytecodeEncoding(aRequest);
MOZ_ASSERT(IsAlreadyHandledForBytecodeEncodingPreparation(aRequest));
return aRv;
}
LOG(("ScriptLoadRequest (%p): Bytecode-cache: disabled (rv = %X)", aRequest,
unsigned(aRv)));
TRACE_FOR_TEST_NONE(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_no_encode");
aRequest->mCacheInfo = nullptr;
MOZ_ASSERT(IsAlreadyHandledForBytecodeEncodingPreparation(aRequest));
return aRv;
}
bool ScriptLoader::IsAlreadyHandledForBytecodeEncodingPreparation(
ScriptLoadRequest* aRequest) {
return aRequest->isInList() || !aRequest->mCacheInfo;
}
void ScriptLoader::MaybePrepareModuleForBytecodeEncodingBeforeExecute(
JSContext* aCx, ModuleLoadRequest* aRequest) {
{
ModuleScript* moduleScript = aRequest->mModuleScript;
JS::Rooted<JSObject*> module(aCx, moduleScript->ModuleRecord());
if (aRequest->IsMarkedForBytecodeEncoding()) {
// This module is imported multiple times, and already marked.
return;
}
if (ShouldCacheBytecode(aRequest)) {
aRequest->MarkModuleForBytecodeEncoding();
}
}
for (ModuleLoadRequest* childRequest : aRequest->mImports) {
MaybePrepareModuleForBytecodeEncodingBeforeExecute(aCx, childRequest);
}
}
nsresult ScriptLoader::MaybePrepareModuleForBytecodeEncodingAfterExecute(
ModuleLoadRequest* aRequest, nsresult aRv) {
if (IsAlreadyHandledForBytecodeEncodingPreparation(aRequest)) {
// This module is imported multiple times and already handled.
return aRv;
}
aRv = MaybePrepareForBytecodeEncodingAfterExecute(aRequest, aRv);
for (ModuleLoadRequest* childRequest : aRequest->mImports) {
aRv = MaybePrepareModuleForBytecodeEncodingAfterExecute(childRequest, aRv);
}
return aRv;
}
nsresult ScriptLoader::EvaluateScript(nsIGlobalObject* aGlobalObject,
ScriptLoadRequest* aRequest) {
nsAutoMicroTask mt;
AutoEntryScript aes(aGlobalObject, "EvaluateScript", true);
JSContext* cx = aes.cx();
nsAutoCString profilerLabelString;
aRequest->GetScriptLoadContext()->GetProfilerLabel(profilerLabelString);
// Create a ClassicScript object and associate it with the JSScript.
RefPtr<ClassicScript> classicScript = new ClassicScript(
aRequest->ReferrerPolicy(), aRequest->mFetchOptions, aRequest->mBaseURL);
JS::Rooted<JS::Value> classicScriptValue(cx, JS::PrivateValue(classicScript));
JS::CompileOptions options(cx);
JS::Rooted<JSScript*> introductionScript(cx);
nsresult rv =
FillCompileOptionsForRequest(cx, aRequest, &options, &introductionScript);
if (NS_FAILED(rv)) {
return rv;
}
// Apply the delazify strategy if the script is small.
if (aRequest->IsTextSource() &&
aRequest->ScriptTextLength() < OffThreadMinimumTextLength &&
ShouldApplyDelazifyStrategy(aRequest)) {
ApplyDelazifyStrategy(&options);
mTotalFullParseSize +=
aRequest->ScriptTextLength() > 0
? static_cast<uint32_t>(aRequest->ScriptTextLength())
: 0;
LOG(
("ScriptLoadRequest (%p): non-on-demand-only (non-omt) Parsing Enabled "
"for url=%s mTotalFullParseSize=%u",
aRequest, aRequest->mURI->GetSpecOrDefault().get(),
mTotalFullParseSize));
}
TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_execute");
JS::Rooted<JSObject*> global(cx, aGlobalObject->GetGlobalJSObject());
JSExecutionContext exec(cx, global, options, classicScriptValue,
introductionScript);
rv = CompileOrDecodeClassicScript(cx, exec, aRequest);
if (NS_FAILED(rv)) {
return rv;
}
// TODO (yulia): rewrite this section. rv can be a failing pattern other than
// NS_OK which will pass the NS_FAILED check above. If we call exec.GetScript
// in that case, it will crash.
if (rv == NS_OK) {
JS::Rooted<JSScript*> script(cx, exec.GetScript());
MaybePrepareForBytecodeEncodingBeforeExecute(aRequest, script);
{
LOG(("ScriptLoadRequest (%p): Evaluate Script", aRequest));
AUTO_PROFILER_MARKER_TEXT("ScriptExecution", JS,
MarkerInnerWindowIdFromJSContext(cx),
profilerLabelString);
rv = ExecuteCompiledScript(cx, exec, classicScript);
}
}
// This must be called also for compilation failure case, in order to
// dispatch test-only event.
rv = MaybePrepareForBytecodeEncodingAfterExecute(aRequest, rv);
// Even if we are not saving the bytecode of the current script, we have
// to trigger the encoding of the bytecode, as the current script can
// call functions of a script for which we are recording the bytecode.
LOG(("ScriptLoadRequest (%p): ScriptLoader = %p", aRequest, this));
MaybeTriggerBytecodeEncoding();
return rv;
}
/* static */
LoadedScript* ScriptLoader::GetActiveScript(JSContext* aCx) {
JS::Value value = JS::GetScriptedCallerPrivate(aCx);
if (value.isUndefined()) {
return nullptr;
}
return static_cast<LoadedScript*>(value.toPrivate());
}
void ScriptLoader::RegisterForBytecodeEncoding(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->mCacheInfo);
MOZ_ASSERT(aRequest->IsMarkedForBytecodeEncoding());
MOZ_DIAGNOSTIC_ASSERT(!aRequest->isInList());
mBytecodeEncodingQueue.AppendElement(aRequest);
}
void ScriptLoader::LoadEventFired() {
mLoadEventFired = true;
MaybeTriggerBytecodeEncoding();
if (!mMainThreadParseTime.IsZero()) {
Telemetry::Accumulate(
Telemetry::JS_PAGELOAD_PARSE_MS,
static_cast<uint32_t>(mMainThreadParseTime.ToMilliseconds()));
}
}
void ScriptLoader::Destroy() {
if (mShutdownObserver) {
mShutdownObserver->Unregister();
mShutdownObserver = nullptr;
}
CancelAndClearScriptLoadRequests();
GiveUpBytecodeEncoding();
}
void ScriptLoader::MaybeTriggerBytecodeEncoding() {
// If we already gave up, ensure that we are not going to enqueue any script,
// and that we finalize them properly.
if (mGiveUpEncoding) {
LOG(("ScriptLoader (%p): Keep giving-up bytecode encoding.", this));
GiveUpBytecodeEncoding();
return;
}
// We wait for the load event to be fired before saving the bytecode of
// any script to the cache. It is quite common to have load event
// listeners trigger more JavaScript execution, that we want to save as
// part of this start-up bytecode cache.
if (!mLoadEventFired) {
LOG(("ScriptLoader (%p): Wait for the load-end event to fire.", this));
return;
}
// No need to fire any event if there is no bytecode to be saved.
if (mBytecodeEncodingQueue.isEmpty()) {
LOG(("ScriptLoader (%p): No script in queue to be encoded.", this));
return;
}
// Wait until all scripts are loaded before saving the bytecode, such that
// we capture most of the intialization of the page.
if (HasPendingRequests()) {
LOG(("ScriptLoader (%p): Wait for other pending request to finish.", this));
return;
}
// Create a new runnable dedicated to encoding the content of the bytecode of
// all enqueued scripts when the document is idle. In case of failure, we
// give-up on encoding the bytecode.
nsCOMPtr<nsIRunnable> encoder = NewRunnableMethod(
"ScriptLoader::EncodeBytecode", this, &ScriptLoader::EncodeBytecode);
if (NS_FAILED(NS_DispatchToCurrentThreadQueue(encoder.forget(),
EventQueuePriority::Idle))) {
GiveUpBytecodeEncoding();
return;
}
LOG(("ScriptLoader (%p): Schedule bytecode encoding.", this));
}
void ScriptLoader::EncodeBytecode() {
LOG(("ScriptLoader (%p): Start bytecode encoding.", this));
// If any script got added in the previous loop cycle, wait until all
// remaining script executions are completed, such that we capture most of
// the initialization.
if (HasPendingRequests()) {
return;
}
// Should not be encoding modules at all.
nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject();
if (!globalObject) {
GiveUpBytecodeEncoding();
return;
}
nsCOMPtr<nsIScriptContext> context = globalObject->GetScriptContext();
if (!context) {
GiveUpBytecodeEncoding();
return;
}
AutoEntryScript aes(globalObject, "encode bytecode", true);
RefPtr<ScriptLoadRequest> request;
while (!mBytecodeEncodingQueue.isEmpty()) {
request = mBytecodeEncodingQueue.StealFirst();
MOZ_ASSERT(!IsWebExtensionRequest(request),
"Bytecode for web extension content scrips is not cached");
EncodeRequestBytecode(aes.cx(), request);
request->mScriptBytecode.clearAndFree();
request->DropBytecodeCacheReferences();
}
}
void ScriptLoader::EncodeRequestBytecode(JSContext* aCx,
ScriptLoadRequest* aRequest) {
using namespace mozilla::Telemetry;
nsresult rv = NS_OK;
MOZ_ASSERT(aRequest->mCacheInfo);
auto bytecodeFailed = mozilla::MakeScopeExit([&]() {
TRACE_FOR_TEST_NONE(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_bytecode_failed");
});
bool result;
if (aRequest->IsModuleRequest()) {
ModuleScript* moduleScript = aRequest->AsModuleRequest()->mModuleScript;
JS::Rooted<JSObject*> module(aCx, moduleScript->ModuleRecord());
result =
JS::FinishIncrementalEncoding(aCx, module, aRequest->mScriptBytecode);
} else {
JS::Rooted<JSScript*> script(aCx, aRequest->mScriptForBytecodeEncoding);
result =
JS::FinishIncrementalEncoding(aCx, script, aRequest->mScriptBytecode);
}
if (!result) {
// Encoding can be aborted for non-supported syntax (e.g. asm.js), or
// any other internal error.
// We don't care the error and just give up encoding.
JS_ClearPendingException(aCx);
LOG(("ScriptLoadRequest (%p): Cannot serialize bytecode", aRequest));
return;
}
Vector<uint8_t> compressedBytecode;
// TODO probably need to move this to a helper thread
if (!ScriptBytecodeCompress(aRequest->mScriptBytecode,
aRequest->mBytecodeOffset, compressedBytecode)) {
return;
}
if (compressedBytecode.length() >= UINT32_MAX) {
LOG(
("ScriptLoadRequest (%p): Bytecode cache is too large to be decoded "
"correctly.",
aRequest));
return;
}
// Open the output stream to the cache entry alternate data storage. This
// might fail if the stream is already open by another request, in which
// case, we just ignore the current one.
nsCOMPtr<nsIAsyncOutputStream> output;
rv = aRequest->mCacheInfo->OpenAlternativeOutputStream(
BytecodeMimeTypeFor(aRequest),
static_cast<int64_t>(compressedBytecode.length()),
getter_AddRefs(output));
if (NS_FAILED(rv)) {
LOG(
("ScriptLoadRequest (%p): Cannot open bytecode cache (rv = %X, output "
"= %p)",
aRequest, unsigned(rv), output.get()));
return;
}
MOZ_ASSERT(output);
auto closeOutStream = mozilla::MakeScopeExit([&]() {
rv = output->CloseWithStatus(rv);
LOG(("ScriptLoadRequest (%p): Closing (rv = %X)", aRequest, unsigned(rv)));
});
uint32_t n;
rv = output->Write(reinterpret_cast<char*>(compressedBytecode.begin()),
compressedBytecode.length(), &n);
LOG(
("ScriptLoadRequest (%p): Write bytecode cache (rv = %X, length = %u, "
"written = %u)",
aRequest, unsigned(rv), unsigned(compressedBytecode.length()), n));
if (NS_FAILED(rv)) {
return;
}
MOZ_RELEASE_ASSERT(compressedBytecode.length() == n);
bytecodeFailed.release();
TRACE_FOR_TEST_NONE(aRequest->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_bytecode_saved");
}
void ScriptLoader::GiveUpBytecodeEncoding() {
// If the document went away prematurely, we still want to set this, in order
// to avoid queuing more scripts.
mGiveUpEncoding = true;
// Ideally we prefer to properly end the incremental encoder, such that we
// would not keep a large buffer around. If we cannot, we fallback on the
// removal of all request from the current list and these large buffers would
// be removed at the same time as the source object.
nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject();
AutoAllowLegacyScriptExecution exemption;
Maybe<AutoEntryScript> aes;
if (globalObject) {
nsCOMPtr<nsIScriptContext> context = globalObject->GetScriptContext();
if (context) {
aes.emplace(globalObject, "give-up bytecode encoding", true);
}
}
while (!mBytecodeEncodingQueue.isEmpty()) {
RefPtr<ScriptLoadRequest> request = mBytecodeEncodingQueue.StealFirst();
LOG(("ScriptLoadRequest (%p): Cannot serialize bytecode", request.get()));
TRACE_FOR_TEST_NONE(request->GetScriptLoadContext()->GetScriptElement(),
"scriptloader_bytecode_failed");
MOZ_ASSERT(!IsWebExtensionRequest(request));
if (aes.isSome()) {
if (request->IsModuleRequest()) {
ModuleScript* moduleScript = request->AsModuleRequest()->mModuleScript;
JS::Rooted<JSObject*> module(aes->cx(), moduleScript->ModuleRecord());
JS::AbortIncrementalEncoding(module);
} else {
JS::Rooted<JSScript*> script(aes->cx(),
request->mScriptForBytecodeEncoding);
JS::AbortIncrementalEncoding(script);
}
}
request->mScriptBytecode.clearAndFree();
request->DropBytecodeCacheReferences();
}
}
bool ScriptLoader::HasPendingRequests() const {
return mParserBlockingRequest || !mXSLTRequests.isEmpty() ||
!mLoadedAsyncRequests.isEmpty() ||
!mNonAsyncExternalScriptInsertedRequests.isEmpty() ||
!mDeferRequests.isEmpty() || HasPendingDynamicImports() ||
!mPendingChildLoaders.IsEmpty();
// mOffThreadCompilingRequests are already being processed.
}
bool ScriptLoader::HasPendingDynamicImports() const {
if (mModuleLoader && mModuleLoader->HasPendingDynamicImports()) {
return true;
}
for (ModuleLoader* loader : mWebExtModuleLoaders) {
if (loader->HasPendingDynamicImports()) {
return true;
}
}
for (ModuleLoader* loader : mShadowRealmModuleLoaders) {
if (loader->HasPendingDynamicImports()) {
return true;
}
}
return false;
}
void ScriptLoader::ProcessPendingRequestsAsync() {
if (HasPendingRequests()) {
nsCOMPtr<nsIRunnable> task =
NewRunnableMethod("dom::ScriptLoader::ProcessPendingRequests", this,
&ScriptLoader::ProcessPendingRequests);
if (mDocument) {
mDocument->Dispatch(task.forget());
} else {
NS_DispatchToCurrentThread(task.forget());
}
}
}
void ScriptLoader::ProcessPendingRequests() {
RefPtr<ScriptLoadRequest> request;
if (mParserBlockingRequest && mParserBlockingRequest->IsFinished() &&
ReadyToExecuteParserBlockingScripts()) {
request.swap(mParserBlockingRequest);
UnblockParser(request);
ProcessRequest(request);
ContinueParserAsync(request);
}
while (ReadyToExecuteParserBlockingScripts() && !mXSLTRequests.isEmpty() &&
mXSLTRequests.getFirst()->IsFinished()) {
request = mXSLTRequests.StealFirst();
ProcessRequest(request);
}
while (ReadyToExecuteScripts() && !mLoadedAsyncRequests.isEmpty()) {
request = mLoadedAsyncRequests.StealFirst();
if (request->IsModuleRequest()) {
ProcessRequest(request);
} else {
CompileOffThreadOrProcessRequest(request);
}
}
while (ReadyToExecuteScripts() &&
!mNonAsyncExternalScriptInsertedRequests.isEmpty() &&
mNonAsyncExternalScriptInsertedRequests.getFirst()->IsFinished()) {
// Violate the HTML5 spec and execute these in the insertion order in
// order to make LABjs and the "order" plug-in for RequireJS work with
// their Gecko-sniffed code path. See
// http://lists.w3.org/Archives/Public/public-html/2010Oct/0088.html
request = mNonAsyncExternalScriptInsertedRequests.StealFirst();
ProcessRequest(request);
}
if (mDeferCheckpointReached && mXSLTRequests.isEmpty()) {
while (ReadyToExecuteScripts() && !mDeferRequests.isEmpty() &&
mDeferRequests.getFirst()->IsFinished()) {
request = mDeferRequests.StealFirst();
ProcessRequest(request);
}
}
while (!mPendingChildLoaders.IsEmpty() &&
ReadyToExecuteParserBlockingScripts()) {
RefPtr<ScriptLoader> child = mPendingChildLoaders[0];
mPendingChildLoaders.RemoveElementAt(0);
child->RemoveParserBlockingScriptExecutionBlocker();
}
if (mDeferCheckpointReached && mDocument && !mParserBlockingRequest &&
mNonAsyncExternalScriptInsertedRequests.isEmpty() &&
mXSLTRequests.isEmpty() && mDeferRequests.isEmpty() &&
MaybeRemovedDeferRequests()) {
return ProcessPendingRequests();
}
if (mDeferCheckpointReached && mDocument && !mParserBlockingRequest &&
mLoadingAsyncRequests.isEmpty() && mLoadedAsyncRequests.isEmpty() &&
mNonAsyncExternalScriptInsertedRequests.isEmpty() &&
mXSLTRequests.isEmpty() && mDeferRequests.isEmpty()) {
// No more pending scripts; time to unblock onload.
// OK to unblock onload synchronously here, since callers must be
// prepared for the world changing anyway.
mDeferCheckpointReached = false;
mDocument->UnblockOnload(true);
}
}
bool ScriptLoader::ReadyToExecuteParserBlockingScripts() {
// Make sure the SelfReadyToExecuteParserBlockingScripts check is first, so
// that we don't block twice on an ancestor.
if (!SelfReadyToExecuteParserBlockingScripts()) {
return false;
}
if (mDocument && mDocument->GetWindowContext()) {
for (WindowContext* wc =
mDocument->GetWindowContext()->GetParentWindowContext();
wc; wc = wc->GetParentWindowContext()) {
if (Document* doc = wc->GetDocument()) {
ScriptLoader* ancestor = doc->ScriptLoader();
if (!ancestor->SelfReadyToExecuteParserBlockingScripts() &&
ancestor->AddPendingChildLoader(this)) {
AddParserBlockingScriptExecutionBlocker();
return false;
}
}
}
}
return true;
}
template <typename Unit>
static nsresult ConvertToUnicode(nsIChannel* aChannel, const uint8_t* aData,
uint32_t aLength,
const nsAString& aHintCharset,
Document* aDocument, Unit*& aBufOut,
size_t& aLengthOut) {
if (!aLength) {
aBufOut = nullptr;
aLengthOut = 0;
return NS_OK;
}
auto data = Span(aData, aLength);
// The encoding info precedence is as follows from high to low:
// The BOM
// HTTP Content-Type (if name recognized)
// charset attribute (if name recognized)
// The encoding of the document
UniquePtr<Decoder> unicodeDecoder;
const Encoding* encoding;
std::tie(encoding, std::ignore) = Encoding::ForBOM(data);
if (encoding) {
unicodeDecoder = encoding->NewDecoderWithBOMRemoval();
}
if (!unicodeDecoder && aChannel) {
nsAutoCString label;
if (NS_SUCCEEDED(aChannel->GetContentCharset(label)) &&
(encoding = Encoding::ForLabel(label))) {
unicodeDecoder = encoding->NewDecoderWithoutBOMHandling();
}
}
if (!unicodeDecoder && (encoding = Encoding::ForLabel(aHintCharset))) {
unicodeDecoder = encoding->NewDecoderWithoutBOMHandling();
}
if (!unicodeDecoder && aDocument) {
unicodeDecoder =
aDocument->GetDocumentCharacterSet()->NewDecoderWithoutBOMHandling();
}
if (!unicodeDecoder) {
// Curiously, there are various callers that don't pass aDocument. The
// fallback in the old code was ISO-8859-1, which behaved like
// windows-1252.
unicodeDecoder = WINDOWS_1252_ENCODING->NewDecoderWithoutBOMHandling();
}
auto signalOOM = mozilla::MakeScopeExit([&aBufOut, &aLengthOut]() {
aBufOut = nullptr;
aLengthOut = 0;
});
CheckedInt<size_t> bufferLength =
ScriptDecoding<Unit>::MaxBufferLength(unicodeDecoder, aLength);
if (!bufferLength.isValid()) {
return NS_ERROR_OUT_OF_MEMORY;
}
CheckedInt<size_t> bufferByteSize = bufferLength * sizeof(Unit);
if (!bufferByteSize.isValid()) {
return NS_ERROR_OUT_OF_MEMORY;
}
aBufOut = static_cast<Unit*>(js_malloc(bufferByteSize.value()));
if (!aBufOut) {
return NS_ERROR_OUT_OF_MEMORY;
}
signalOOM.release();
aLengthOut = ScriptDecoding<Unit>::DecodeInto(
unicodeDecoder, data, Span(aBufOut, bufferLength.value()),
/* aEndOfSource = */ true);
return NS_OK;
}
/* static */
nsresult ScriptLoader::ConvertToUTF16(
nsIChannel* aChannel, const uint8_t* aData, uint32_t aLength,
const nsAString& aHintCharset, Document* aDocument,
UniquePtr<char16_t[], JS::FreePolicy>& aBufOut, size_t& aLengthOut) {
char16_t* bufOut;
nsresult rv = ConvertToUnicode(aChannel, aData, aLength, aHintCharset,
aDocument, bufOut, aLengthOut);
if (NS_SUCCEEDED(rv)) {
aBufOut.reset(bufOut);
}
return rv;
}
/* static */
nsresult ScriptLoader::ConvertToUTF8(
nsIChannel* aChannel, const uint8_t* aData, uint32_t aLength,
const nsAString& aHintCharset, Document* aDocument,
UniquePtr<Utf8Unit[], JS::FreePolicy>& aBufOut, size_t& aLengthOut) {
Utf8Unit* bufOut;
nsresult rv = ConvertToUnicode(aChannel, aData, aLength, aHintCharset,
aDocument, bufOut, aLengthOut);
if (NS_SUCCEEDED(rv)) {
aBufOut.reset(bufOut);
}
return rv;
}
nsresult ScriptLoader::OnStreamComplete(
nsIIncrementalStreamLoader* aLoader, ScriptLoadRequest* aRequest,
nsresult aChannelStatus, nsresult aSRIStatus,
SRICheckDataVerifier* aSRIDataVerifier) {
NS_ASSERTION(aRequest, "null request in stream complete handler");
NS_ENSURE_TRUE(aRequest, NS_ERROR_FAILURE);
nsresult rv = VerifySRI(aRequest, aLoader, aSRIStatus, aSRIDataVerifier);
if (NS_SUCCEEDED(rv)) {
// If we are loading from source, save the computed SRI hash or a dummy SRI
// hash in case we are going to save the bytecode of this script in the
// cache.
if (aRequest->IsSource()) {
uint32_t sriLength = 0;
rv = SaveSRIHash(aRequest, aSRIDataVerifier, &sriLength);
MOZ_ASSERT_IF(NS_SUCCEEDED(rv),
aRequest->mScriptBytecode.length() == sriLength);
aRequest->mBytecodeOffset = JS::AlignTranscodingBytecodeOffset(sriLength);
if (aRequest->mBytecodeOffset != sriLength) {
// We need extra padding after SRI hash.
if (!aRequest->mScriptBytecode.resize(aRequest->mBytecodeOffset)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
}
if (NS_SUCCEEDED(rv)) {
rv = PrepareLoadedRequest(aRequest, aLoader, aChannelStatus);
}
if (NS_FAILED(rv)) {
ReportErrorToConsole(aRequest, rv);
}
}
if (NS_FAILED(rv)) {
// When loading bytecode, we verify the SRI hash. If it does not match the
// one from the document we restart the load, forcing us to load the source
// instead. If this happens do not remove the current request from script
// loader's data structures or fire any events.
if (aChannelStatus != NS_BINDING_RETARGETED) {
HandleLoadError(aRequest, rv);
}
}
// Process our request and/or any pending ones
ProcessPendingRequests();
return rv;
}
nsresult ScriptLoader::VerifySRI(ScriptLoadRequest* aRequest,
nsIIncrementalStreamLoader* aLoader,
nsresult aSRIStatus,
SRICheckDataVerifier* aSRIDataVerifier) const {
nsCOMPtr<nsIRequest> channelRequest;
aLoader->GetRequest(getter_AddRefs(channelRequest));
nsCOMPtr<nsIChannel> channel;
channel = do_QueryInterface(channelRequest);
nsresult rv = NS_OK;
if (!aRequest->mIntegrity.IsEmpty() && NS_SUCCEEDED((rv = aSRIStatus))) {
MOZ_ASSERT(aSRIDataVerifier);
MOZ_ASSERT(mReporter);
nsAutoCString sourceUri;
if (mDocument && mDocument->GetDocumentURI()) {
mDocument->GetDocumentURI()->GetAsciiSpec(sourceUri);
}
rv = aSRIDataVerifier->Verify(aRequest->mIntegrity, channel, sourceUri,
mReporter);
if (channelRequest) {
mReporter->FlushReportsToConsole(
nsContentUtils::GetInnerWindowID(channelRequest));
} else {
mReporter->FlushConsoleReports(mDocument);
}
if (NS_FAILED(rv)) {
rv = NS_ERROR_SRI_CORRUPT;
}
}
return rv;
}
nsresult ScriptLoader::SaveSRIHash(ScriptLoadRequest* aRequest,
SRICheckDataVerifier* aSRIDataVerifier,
uint32_t* sriLength) const {
MOZ_ASSERT(aRequest->IsSource());
MOZ_ASSERT(aRequest->mScriptBytecode.empty());
uint32_t len;
// If the integrity metadata does not correspond to a valid hash function,
// IsComplete would be false.
if (!aRequest->mIntegrity.IsEmpty() && aSRIDataVerifier->IsComplete()) {
MOZ_ASSERT(aRequest->mScriptBytecode.length() == 0);
// Encode the SRI computed hash.
len = aSRIDataVerifier->DataSummaryLength();
if (!aRequest->mScriptBytecode.resize(len)) {
return NS_ERROR_OUT_OF_MEMORY;
}
DebugOnly<nsresult> res = aSRIDataVerifier->ExportDataSummary(
len, aRequest->mScriptBytecode.begin());
MOZ_ASSERT(NS_SUCCEEDED(res));
} else {
MOZ_ASSERT(aRequest->mScriptBytecode.length() == 0);
// Encode a dummy SRI hash.
len = SRICheckDataVerifier::EmptyDataSummaryLength();
if (!aRequest->mScriptBytecode.resize(len)) {
return NS_ERROR_OUT_OF_MEMORY;
}
DebugOnly<nsresult> res = SRICheckDataVerifier::ExportEmptyDataSummary(
len, aRequest->mScriptBytecode.begin());
MOZ_ASSERT(NS_SUCCEEDED(res));
}
// Verify that the exported and predicted length correspond.
DebugOnly<uint32_t> srilen{};
MOZ_ASSERT(NS_SUCCEEDED(SRICheckDataVerifier::DataSummaryLength(
len, aRequest->mScriptBytecode.begin(), &srilen)));
MOZ_ASSERT(srilen == len);
*sriLength = len;
return NS_OK;
}
void ScriptLoader::ReportErrorToConsole(ScriptLoadRequest* aRequest,
nsresult aResult) const {
MOZ_ASSERT(aRequest);
if (aRequest->GetScriptLoadContext()->IsPreload()) {
// Skip reporting errors in preload requests. If the request is actually
// used then we will report the error in ReportPreloadErrorsToConsole below.
aRequest->GetScriptLoadContext()->mUnreportedPreloadError = aResult;
return;
}
bool isScript = !aRequest->IsModuleRequest();
const char* message;
if (aResult == NS_ERROR_MALFORMED_URI) {
message = isScript ? "ScriptSourceMalformed" : "ModuleSourceMalformed";
} else if (aResult == NS_ERROR_DOM_BAD_URI) {
message = isScript ? "ScriptSourceNotAllowed" : "ModuleSourceNotAllowed";
} else if (aResult == NS_ERROR_DOM_WEBEXT_CONTENT_SCRIPT_URI) {
MOZ_ASSERT(!isScript);
message = "WebExtContentScriptModuleSourceNotAllowed";
} else if (net::UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode(
aResult)) {
// Blocking classifier error codes already show their own console messages.
return;
} else {
message = isScript ? "ScriptSourceLoadFailed" : "ModuleSourceLoadFailed";
}
AutoTArray<nsString, 1> params;
CopyUTF8toUTF16(aRequest->mURI->GetSpecOrDefault(), *params.AppendElement());
nsIScriptElement* element =
aRequest->GetScriptLoadContext()->GetScriptElement();
uint32_t lineNo = element ? element->GetScriptLineNumber() : 0;
JS::ColumnNumberOneOrigin columnNo;
if (element) {
columnNo = element->GetScriptColumnNumber();
}
nsContentUtils::ReportToConsole(
nsIScriptError::warningFlag, "Script Loader"_ns, mDocument,
nsContentUtils::eDOM_PROPERTIES, message, params, nullptr, u""_ns, lineNo,
columnNo.oneOriginValue());
}
void ScriptLoader::ReportWarningToConsole(
ScriptLoadRequest* aRequest, const char* aMessageName,
const nsTArray<nsString>& aParams) const {
nsIScriptElement* element =
aRequest->GetScriptLoadContext()->GetScriptElement();
uint32_t lineNo = element ? element->GetScriptLineNumber() : 0;
JS::ColumnNumberOneOrigin columnNo;
if (element) {
columnNo = element->GetScriptColumnNumber();
}
nsContentUtils::ReportToConsole(
nsIScriptError::warningFlag, "Script Loader"_ns, mDocument,
nsContentUtils::eDOM_PROPERTIES, aMessageName, aParams, nullptr, u""_ns,
lineNo, columnNo.oneOriginValue());
}
void ScriptLoader::ReportPreloadErrorsToConsole(ScriptLoadRequest* aRequest) {
if (NS_FAILED(aRequest->GetScriptLoadContext()->mUnreportedPreloadError)) {
ReportErrorToConsole(
aRequest, aRequest->GetScriptLoadContext()->mUnreportedPreloadError);
aRequest->GetScriptLoadContext()->mUnreportedPreloadError = NS_OK;
}
if (aRequest->IsModuleRequest()) {
for (const auto& childRequest : aRequest->AsModuleRequest()->mImports) {
ReportPreloadErrorsToConsole(childRequest);
}
}
}
void ScriptLoader::HandleLoadError(ScriptLoadRequest* aRequest,
nsresult aResult) {
/*
* Handle script not loading error because source was an tracking URL (or
* fingerprinting, cryptomining, etc).
* We make a note of this script node by including it in a dedicated
* array of blocked tracking nodes under its parent document.
*/
if (net::UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode(
aResult)) {
nsCOMPtr<nsIContent> cont =
do_QueryInterface(aRequest->GetScriptLoadContext()->GetScriptElement());
mDocument->AddBlockedNodeByClassifier(cont);
}
if (aRequest->IsModuleRequest()) {
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mIsInline);
aRequest->AsModuleRequest()->OnFetchComplete(aResult);
}
if (aRequest->GetScriptLoadContext()->mInDeferList) {
MOZ_ASSERT_IF(aRequest->IsModuleRequest(),
aRequest->AsModuleRequest()->IsTopLevel());
if (aRequest->isInList()) {
RefPtr<ScriptLoadRequest> req = mDeferRequests.Steal(aRequest);
FireScriptAvailable(aResult, req);
}
} else if (aRequest->GetScriptLoadContext()->mInAsyncList) {
MOZ_ASSERT_IF(aRequest->IsModuleRequest(),
aRequest->AsModuleRequest()->IsTopLevel());
if (aRequest->isInList()) {
RefPtr<ScriptLoadRequest> req = mLoadingAsyncRequests.Steal(aRequest);
FireScriptAvailable(aResult, req);
}
} else if (aRequest->GetScriptLoadContext()->mIsNonAsyncScriptInserted) {
if (aRequest->isInList()) {
RefPtr<ScriptLoadRequest> req =
mNonAsyncExternalScriptInsertedRequests.Steal(aRequest);
FireScriptAvailable(aResult, req);
}
} else if (aRequest->GetScriptLoadContext()->mIsXSLT) {
if (aRequest->isInList()) {
RefPtr<ScriptLoadRequest> req = mXSLTRequests.Steal(aRequest);
FireScriptAvailable(aResult, req);
}
} else if (aRequest->GetScriptLoadContext()->IsPreload()) {
if (aRequest->IsModuleRequest()) {
aRequest->Cancel();
}
if (aRequest->IsTopLevel()) {
// Request may already have been removed by
// CancelAndClearScriptLoadRequests.
mPreloads.RemoveElement(aRequest, PreloadRequestComparator());
}
MOZ_ASSERT(!aRequest->isInList());
AccumulateCategorical(LABELS_DOM_SCRIPT_PRELOAD_RESULT::LoadError);
} else if (aRequest->IsModuleRequest()) {
ModuleLoadRequest* modReq = aRequest->AsModuleRequest();
if (modReq->IsDynamicImport()) {
MOZ_ASSERT(modReq->IsTopLevel());
if (aRequest->isInList()) {
modReq->CancelDynamicImport(aResult);
}
} else {
MOZ_ASSERT(!modReq->isInList());
modReq->Cancel();
}
} else if (mParserBlockingRequest == aRequest) {
MOZ_ASSERT(!aRequest->isInList());
mParserBlockingRequest = nullptr;
UnblockParser(aRequest);
// Ensure that we treat aRequest->GetScriptLoadContext()->GetScriptElement()
// as our current parser-inserted script while firing onerror on it.
MOZ_ASSERT(aRequest->GetScriptLoadContext()
->GetScriptElement()
->GetParserCreated());
nsCOMPtr<nsIScriptElement> oldParserInsertedScript =
mCurrentParserInsertedScript;
mCurrentParserInsertedScript =
aRequest->GetScriptLoadContext()->GetScriptElement();
FireScriptAvailable(aResult, aRequest);
ContinueParserAsync(aRequest);
mCurrentParserInsertedScript = oldParserInsertedScript;
} else {
// This happens for blocking requests cancelled by ParsingComplete().
// Ignore cancellation status for link-preload requests, as cancellation can
// be omitted for them when SRI is stronger on consumer tags.
MOZ_ASSERT(aRequest->IsCanceled() ||
aRequest->GetScriptLoadContext()->IsLinkPreloadScript());
MOZ_ASSERT(!aRequest->isInList());
}
}
void ScriptLoader::UnblockParser(ScriptLoadRequest* aParserBlockingRequest) {
aParserBlockingRequest->GetScriptLoadContext()
->GetScriptElement()
->UnblockParser();
}
void ScriptLoader::ContinueParserAsync(
ScriptLoadRequest* aParserBlockingRequest) {
aParserBlockingRequest->GetScriptLoadContext()
->GetScriptElement()
->ContinueParserAsync();
}
uint32_t ScriptLoader::NumberOfProcessors() {
if (mNumberOfProcessors > 0) {
return mNumberOfProcessors;
}
int32_t numProcs = PR_GetNumberOfProcessors();
if (numProcs > 0) {
mNumberOfProcessors = numProcs;
}
return mNumberOfProcessors;
}
int32_t ScriptLoader::PhysicalSizeOfMemoryInGB() {
// 0 is a valid result from PR_GetPhysicalMemorySize() which
// means a failure occured.
if (mPhysicalSizeOfMemory >= 0) {
return mPhysicalSizeOfMemory;
}
// Save the size in GB.
mPhysicalSizeOfMemory =
static_cast<int32_t>(PR_GetPhysicalMemorySize() >> 30);
return mPhysicalSizeOfMemory;
}
static bool IsInternalURIScheme(nsIURI* uri) {
return uri->SchemeIs("moz-extension") || uri->SchemeIs("resource") ||
uri->SchemeIs("chrome");
}
bool ScriptLoader::ShouldApplyDelazifyStrategy(ScriptLoadRequest* aRequest) {
// Full parse everything if negative.
if (StaticPrefs::dom_script_loader_delazification_max_size() < 0) {
return true;
}
// Be conservative on machines with 2GB or less of memory.
if (PhysicalSizeOfMemoryInGB() <=
StaticPrefs::dom_script_loader_delazification_min_mem()) {
return false;
}
uint32_t max_size = static_cast<uint32_t>(
StaticPrefs::dom_script_loader_delazification_max_size());
uint32_t script_size =
aRequest->ScriptTextLength() > 0
? static_cast<uint32_t>(aRequest->ScriptTextLength())
: 0;
if (mTotalFullParseSize + script_size < max_size) {
return true;
}
if (LOG_ENABLED()) {
nsCString url = aRequest->mURI->GetSpecOrDefault();
LOG(
("ScriptLoadRequest (%p): non-on-demand-only Parsing Disabled for (%s) "
"with size=%u because mTotalFullParseSize=%u would exceed max_size=%u",
aRequest, url.get(), script_size, mTotalFullParseSize, max_size));
}
return false;
}
void ScriptLoader::ApplyDelazifyStrategy(JS::CompileOptions* aOptions) {
JS::DelazificationOption strategy =
JS::DelazificationOption::ParseEverythingEagerly;
uint32_t strategyIndex =
StaticPrefs::dom_script_loader_delazification_strategy();
// Assert that all enumerated values of DelazificationOption are dense between
// OnDemandOnly and ParseEverythingEagerly.
#ifdef DEBUG
uint32_t count = 0;
uint32_t mask = 0;
# define _COUNT_ENTRIES(Name) count++;
# define _MASK_ENTRIES(Name) \
mask |= 1 << uint32_t(JS::DelazificationOption::Name);
FOREACH_DELAZIFICATION_STRATEGY(_COUNT_ENTRIES);
MOZ_ASSERT(count == uint32_t(strategy) + 1);
FOREACH_DELAZIFICATION_STRATEGY(_MASK_ENTRIES);
MOZ_ASSERT(((mask + 1) & mask) == 0);
# undef _COUNT_ENTRIES
# undef _MASK_ENTRIES
#endif
// Any strategy index larger than ParseEverythingEagerly would default to
// ParseEverythingEagerly.
if (strategyIndex <= uint32_t(strategy)) {
strategy = JS::DelazificationOption(uint8_t(strategyIndex));
}
aOptions->setEagerDelazificationStrategy(strategy);
}
bool ScriptLoader::ShouldCompileOffThread(ScriptLoadRequest* aRequest) {
if (NumberOfProcessors() <= 1) {
return false;
}
if (aRequest == mParserBlockingRequest) {
return true;
}
if (SpeculativeOMTParsingEnabled()) {
// Processing non async inserted scripts too early can potentially delay the
// load event from firing so focus on other scripts instead.
if (aRequest->GetScriptLoadContext()->mIsNonAsyncScriptInserted &&
!StaticPrefs::
dom_script_loader_external_scripts_speculate_non_parser_inserted_enabled()) {
return false;
}
// Async and link preload scripts do not need to be parsed right away.
if (aRequest->GetScriptLoadContext()->IsAsyncScript() &&
!StaticPrefs::
dom_script_loader_external_scripts_speculate_async_enabled()) {
return false;
}
if (aRequest->GetScriptLoadContext()->IsLinkPreloadScript() &&
!StaticPrefs::
dom_script_loader_external_scripts_speculate_link_preload_enabled()) {
return false;
}
return true;
}
return false;
}
nsresult ScriptLoader::PrepareLoadedRequest(ScriptLoadRequest* aRequest,
nsIIncrementalStreamLoader* aLoader,
nsresult aStatus) {
if (NS_FAILED(aStatus)) {
return aStatus;
}
if (aRequest->IsCanceled()) {
return NS_BINDING_ABORTED;
}
MOZ_ASSERT(aRequest->IsFetching());
CollectScriptTelemetry(aRequest);
// If we don't have a document, then we need to abort further
// evaluation.
if (!mDocument) {
return NS_ERROR_NOT_AVAILABLE;
}
// If the load returned an error page, then we need to abort
nsCOMPtr<nsIRequest> req;
nsresult rv = aLoader->GetRequest(getter_AddRefs(req));
NS_ASSERTION(req, "StreamLoader's request went away prematurely");
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(req);
if (httpChannel) {
bool requestSucceeded;
rv = httpChannel->GetRequestSucceeded(&requestSucceeded);
if (NS_SUCCEEDED(rv) && !requestSucceeded) {
return NS_ERROR_NOT_AVAILABLE;
}
if (aRequest->IsModuleRequest()) {
// https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-single-module-script
// Update script's referrer-policy if there's a Referrer-Policy header in
// the HTTP response.
ReferrerPolicy policy =
nsContentUtils::GetReferrerPolicyFromChannel(httpChannel);
if (policy != ReferrerPolicy::_empty) {
aRequest->UpdateReferrerPolicy(policy);
}
}
nsAutoCString sourceMapURL;
if (nsContentUtils::GetSourceMapURL(httpChannel, sourceMapURL)) {
aRequest->mSourceMapURL = Some(NS_ConvertUTF8toUTF16(sourceMapURL));
}
nsCOMPtr<nsIClassifiedChannel> classifiedChannel = do_QueryInterface(req);
MOZ_ASSERT(classifiedChannel);
if (classifiedChannel &&
classifiedChannel->IsThirdPartyTrackingResource()) {
aRequest->GetScriptLoadContext()->SetIsTracking();
}
}
nsCOMPtr<nsIChannel> channel = do_QueryInterface(req);
// If this load was subject to a CORS check, don't flag it with a separate
// origin principal, so that it will treat our document's principal as the
// origin principal. Module loads always use CORS.
if (!aRequest->IsModuleRequest() && aRequest->CORSMode() == CORS_NONE) {
rv = nsContentUtils::GetSecurityManager()->GetChannelResultPrincipal(
channel, getter_AddRefs(aRequest->mOriginPrincipal));
NS_ENSURE_SUCCESS(rv, rv);
}
// This assertion could fire errorously if we ran out of memory when
// inserting the request in the array. However it's an unlikely case
// so if you see this assertion it is likely something else that is
// wrong, especially if you see it more than once.
NS_ASSERTION(mDeferRequests.Contains(aRequest) ||
mLoadingAsyncRequests.Contains(aRequest) ||
mNonAsyncExternalScriptInsertedRequests.Contains(aRequest) ||
mXSLTRequests.Contains(aRequest) ||
(aRequest->IsModuleRequest() &&
(aRequest->AsModuleRequest()->IsRegisteredDynamicImport() ||
!aRequest->AsModuleRequest()->IsTopLevel())) ||
mPreloads.Contains(aRequest, PreloadRequestComparator()) ||
mParserBlockingRequest == aRequest,
"aRequest should be pending!");
nsCOMPtr<nsIURI> uri;
rv = channel->GetOriginalURI(getter_AddRefs(uri));
NS_ENSURE_SUCCESS(rv, rv);
// Fixup moz-extension: and resource: URIs, because the channel URI will
// point to file:, which won't be allowed to load.
if (uri && IsInternalURIScheme(uri)) {
aRequest->mBaseURL = uri;
} else {
channel->GetURI(getter_AddRefs(aRequest->mBaseURL));
}
if (aRequest->IsModuleRequest()) {
ModuleLoadRequest* request = aRequest->AsModuleRequest();
// When loading a module, only responses with a JavaScript MIME type are
// acceptable.
nsAutoCString mimeType;
channel->GetContentType(mimeType);
NS_ConvertUTF8toUTF16 typeString(mimeType);
if (!nsContentUtils::IsJavascriptMIMEType(typeString)) {
return NS_ERROR_FAILURE;
}
// Attempt to compile off main thread.
bool couldCompile = false;
rv = AttemptOffThreadScriptCompile(request, &couldCompile);
NS_ENSURE_SUCCESS(rv, rv);
if (couldCompile) {
return NS_OK;
}
// Otherwise compile it right away and start fetching descendents.
return request->OnFetchComplete(NS_OK);
}
// The script is now loaded and ready to run.
aRequest->SetReady();
// If speculative parsing is enabled attempt to compile all
// external scripts off-main-thread. Otherwise, only omt compile scripts
// blocking the parser.
if (ShouldCompileOffThread(aRequest)) {
MOZ_ASSERT(!aRequest->IsModuleRequest());
bool couldCompile = false;
nsresult rv = AttemptOffThreadScriptCompile(aRequest, &couldCompile);
NS_ENSURE_SUCCESS(rv, rv);
if (couldCompile) {
MOZ_ASSERT(aRequest->mState == ScriptLoadRequest::State::Compiling,
"Request should be off-thread compiling now.");
return NS_OK;
}
// If off-thread compile was rejected, continue with regular processing.
}
MaybeMoveToLoadedList(aRequest);
return NS_OK;
}
void ScriptLoader::DeferCheckpointReached() {
if (mDeferEnabled) {
// Have to check because we apparently get ParsingComplete
// without BeginDeferringScripts in some cases
mDeferCheckpointReached = true;
}
mDeferEnabled = false;
ProcessPendingRequests();
}
void ScriptLoader::ParsingComplete(bool aTerminated) {
if (aTerminated) {
CancelAndClearScriptLoadRequests();
// Have to call this even if aTerminated so we'll correctly unblock onload.
DeferCheckpointReached();
}
}
void ScriptLoader::PreloadURI(
nsIURI* aURI, const nsAString& aCharset, const nsAString& aType,
const nsAString& aCrossOrigin, const nsAString& aNonce,
const nsAString& aFetchPriority, const nsAString& aIntegrity,
bool aScriptFromHead, bool aAsync, bool aDefer, bool aLinkPreload,
const ReferrerPolicy aReferrerPolicy, uint64_t aEarlyHintPreloaderId) {
NS_ENSURE_TRUE_VOID(mDocument);
// Check to see if scripts has been turned off.
if (!mEnabled || !mDocument->IsScriptEnabled()) {
return;
}
ScriptKind scriptKind = ScriptKind::eClassic;
static const char kASCIIWhitespace[] = "\t\n\f\r ";
nsAutoString type(aType);
type.Trim(kASCIIWhitespace);
if (type.LowerCaseEqualsASCII("module")) {
scriptKind = ScriptKind::eModule;
}
if (scriptKind == ScriptKind::eClassic && !aType.IsEmpty() &&
!nsContentUtils::IsJavascriptMIMEType(aType)) {
// Unknown type. Don't load it.
return;
}
SRIMetadata sriMetadata;
GetSRIMetadata(aIntegrity, &sriMetadata);
const auto requestPriority = FetchPriorityToRequestPriority(
nsGenericHTMLElement::ToFetchPriority(aFetchPriority));
// For link type "modulepreload":
// https://html.spec.whatwg.org/multipage/links.html#link-type-modulepreload
// Step 11. Let options be a script fetch options whose cryptographic nonce is
// cryptographic nonce, integrity metadata is integrity metadata, parser
// metadata is "not-parser-inserted", credentials mode is credentials mode,
// referrer policy is referrer policy, and fetch priority is fetch priority.
//
// We treat speculative <script> loads as parser-inserted, because they
// come from a parser. This will also match how they should be treated
// as a normal load.
RefPtr<ScriptLoadRequest> request =
CreateLoadRequest(scriptKind, aURI, nullptr, mDocument->NodePrincipal(),
Element::StringToCORSMode(aCrossOrigin), aNonce,
requestPriority, sriMetadata, aReferrerPolicy,
aLinkPreload ? ParserMetadata::NotParserInserted
: ParserMetadata::ParserInserted);
request->GetScriptLoadContext()->mIsInline = false;
request->GetScriptLoadContext()->mScriptFromHead = aScriptFromHead;
request->GetScriptLoadContext()->SetScriptMode(aDefer, aAsync, aLinkPreload);
request->GetScriptLoadContext()->SetIsPreloadRequest();
request->mEarlyHintPreloaderId = aEarlyHintPreloaderId;
if (LOG_ENABLED()) {
nsAutoCString url;
aURI->GetAsciiSpec(url);
LOG(("ScriptLoadRequest (%p): Created preload request for %s",
request.get(), url.get()));
}
nsAutoString charset(aCharset);
nsresult rv = StartLoad(request, Some(charset));
if (NS_FAILED(rv)) {
return;
}
PreloadInfo* pi = mPreloads.AppendElement();
pi->mRequest = request;
pi->mCharset = aCharset;
}
void ScriptLoader::AddDeferRequest(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->GetScriptLoadContext()->IsDeferredScript());
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mInDeferList &&
!aRequest->GetScriptLoadContext()->mInAsyncList);
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mInCompilingList);
aRequest->GetScriptLoadContext()->mInDeferList = true;
mDeferRequests.AppendElement(aRequest);
if (mDeferEnabled && aRequest == mDeferRequests.getFirst() && mDocument &&
!mBlockingDOMContentLoaded) {
MOZ_ASSERT(mDocument->GetReadyStateEnum() == Document::READYSTATE_LOADING);
mBlockingDOMContentLoaded = true;
mDocument->BlockDOMContentLoaded();
}
}
void ScriptLoader::AddAsyncRequest(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->GetScriptLoadContext()->IsAsyncScript());
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mInDeferList &&
!aRequest->GetScriptLoadContext()->mInAsyncList);
MOZ_ASSERT(!aRequest->GetScriptLoadContext()->mInCompilingList);
aRequest->GetScriptLoadContext()->mInAsyncList = true;
if (aRequest->IsFinished()) {
mLoadedAsyncRequests.AppendElement(aRequest);
} else {
mLoadingAsyncRequests.AppendElement(aRequest);
}
}
void ScriptLoader::MaybeMoveToLoadedList(ScriptLoadRequest* aRequest) {
MOZ_ASSERT(aRequest->IsFinished());
MOZ_ASSERT(aRequest->IsTopLevel());
// If it's async, move it to the loaded list.
// aRequest->GetScriptLoadContext()->mInAsyncList really _should_ be in a
// list, but the consequences if it's not are bad enough we want to avoid
// trying to move it if it's not.
if (aRequest->GetScriptLoadContext()->mInAsyncList) {
MOZ_ASSERT(aRequest->isInList());
if (aRequest->isInList()) {
RefPtr<ScriptLoadRequest> req = mLoadingAsyncRequests.Steal(aRequest);
mLoadedAsyncRequests.AppendElement(req);
}
} else if (aRequest->IsModuleRequest() &&
aRequest->AsModuleRequest()->IsDynamicImport()) {
// Process dynamic imports with async scripts.
MOZ_ASSERT(!aRequest->isInList());
mLoadedAsyncRequests.AppendElement(aRequest);
}
}
bool ScriptLoader::MaybeRemovedDeferRequests() {
if (mDeferRequests.isEmpty() && mDocument && mBlockingDOMContentLoaded) {
mBlockingDOMContentLoaded = false;
mDocument->UnblockDOMContentLoaded();
return true;
}
return false;
}
DocGroup* ScriptLoader::GetDocGroup() const { return mDocument->GetDocGroup(); }
void ScriptLoader::BeginDeferringScripts() {
mDeferEnabled = true;
if (mDeferCheckpointReached) {
// We already completed a parse and were just waiting for some async
// scripts to load (and were already blocking the load event waiting for
// that to happen), when document.open() happened and now we're doing a
// new parse. We shouldn't block the load event again, but _should_ reset
// mDeferCheckpointReached to false. It'll get set to true again when the
// DeferCheckpointReached call that corresponds to this
// BeginDeferringScripts call happens (on document.close()), since we just
// set mDeferEnabled to true.
mDeferCheckpointReached = false;
} else {
if (mDocument) {
mDocument->BlockOnload();
}
}
}
nsAutoScriptLoaderDisabler::nsAutoScriptLoaderDisabler(Document* aDoc) {
mLoader = aDoc->ScriptLoader();
mWasEnabled = mLoader->GetEnabled();
if (mWasEnabled) {
mLoader->SetEnabled(false);
}
}
nsAutoScriptLoaderDisabler::~nsAutoScriptLoaderDisabler() {
if (mWasEnabled) {
mLoader->SetEnabled(true);
}
}
#undef TRACE_FOR_TEST
#undef TRACE_FOR_TEST_BOOL
#undef TRACE_FOR_TEST_NONE
#undef LOG
} // namespace mozilla::dom
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