/* -*- 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 "GeckoProfiler.h" #include "LoadedScript.h" #include "ModuleLoadRequest.h" #include "ScriptLoadRequest.h" #include "mozilla/dom/ScriptSettings.h" // AutoJSAPI #include "mozilla/dom/ScriptTrace.h" #include "js/Array.h" // JS::GetArrayLength #include "js/CompilationAndEvaluation.h" #include "js/ColumnNumber.h" // JS::ColumnNumberOneOrigin #include "js/ContextOptions.h" // JS::ContextOptionsRef #include "js/ErrorReport.h" // JSErrorBase #include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_* #include "js/Modules.h" // JS::FinishDynamicModuleImport, JS::{G,S}etModuleResolveHook, JS::Get{ModulePrivate,ModuleScript,RequestedModule{s,Specifier,SourcePos}}, JS::SetModule{DynamicImport,Metadata}Hook #include "js/PropertyAndElement.h" // JS_DefineProperty, JS_GetElement #include "js/SourceText.h" #include "mozilla/Assertions.h" // MOZ_ASSERT #include "mozilla/BasePrincipal.h" #include "mozilla/dom/AutoEntryScript.h" #include "mozilla/dom/ScriptLoadContext.h" #include "mozilla/CycleCollectedJSContext.h" // nsAutoMicroTask #include "mozilla/Preferences.h" #include "mozilla/RefPtr.h" // mozilla::StaticRefPtr #include "mozilla/StaticPrefs_dom.h" #include "nsContentUtils.h" #include "nsICacheInfoChannel.h" // nsICacheInfoChannel #include "nsNetUtil.h" // NS_NewURI #include "xpcpublic.h" using mozilla::CycleCollectedJSContext; using mozilla::Err; using mozilla::Preferences; using mozilla::UniquePtr; using mozilla::WrapNotNull; using mozilla::dom::AutoJSAPI; namespace JS::loader { mozilla::LazyLogModule ModuleLoaderBase::gCspPRLog("CSP"); mozilla::LazyLogModule ModuleLoaderBase::gModuleLoaderBaseLog( "ModuleLoaderBase"); #undef LOG #define LOG(args) \ MOZ_LOG(ModuleLoaderBase::gModuleLoaderBaseLog, mozilla::LogLevel::Debug, \ args) #define LOG_ENABLED() \ MOZ_LOG_TEST(ModuleLoaderBase::gModuleLoaderBaseLog, mozilla::LogLevel::Debug) ////////////////////////////////////////////////////////////// // ModuleLoaderBase::WaitingRequests ////////////////////////////////////////////////////////////// NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ModuleLoaderBase::WaitingRequests) NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_END NS_IMPL_CYCLE_COLLECTION(ModuleLoaderBase::WaitingRequests, mWaiting) NS_IMPL_CYCLE_COLLECTING_ADDREF(ModuleLoaderBase::WaitingRequests) NS_IMPL_CYCLE_COLLECTING_RELEASE(ModuleLoaderBase::WaitingRequests) ////////////////////////////////////////////////////////////// // ModuleLoaderBase ////////////////////////////////////////////////////////////// NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ModuleLoaderBase) NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_END NS_IMPL_CYCLE_COLLECTION(ModuleLoaderBase, mFetchingModules, mFetchedModules, mDynamicImportRequests, mGlobalObject, mLoader) NS_IMPL_CYCLE_COLLECTING_ADDREF(ModuleLoaderBase) NS_IMPL_CYCLE_COLLECTING_RELEASE(ModuleLoaderBase) // static void ModuleLoaderBase::EnsureModuleHooksInitialized() { AutoJSAPI jsapi; jsapi.Init(); JSRuntime* rt = JS_GetRuntime(jsapi.cx()); if (JS::GetModuleResolveHook(rt)) { return; } JS::SetModuleResolveHook(rt, HostResolveImportedModule); JS::SetModuleMetadataHook(rt, HostPopulateImportMeta); JS::SetScriptPrivateReferenceHooks(rt, HostAddRefTopLevelScript, HostReleaseTopLevelScript); JS::SetModuleDynamicImportHook(rt, HostImportModuleDynamically); } // 8.1.3.8.1 HostResolveImportedModule(referencingModule, moduleRequest) /** * Implement the HostResolveImportedModule abstract operation. * * Resolve a module specifier string and look this up in the module * map, returning the result. This is only called for previously * loaded modules and always succeeds. * * @param aReferencingPrivate A JS::Value which is either undefined * or contains a LoadedScript private pointer. * @param aModuleRequest A module request object. * @returns module This is set to the module found. */ // static JSObject* ModuleLoaderBase::HostResolveImportedModule( JSContext* aCx, JS::Handle aReferencingPrivate, JS::Handle aModuleRequest) { JS::Rooted module(aCx); { // LoadedScript should only live in this block, otherwise it will be a GC // hazard RefPtr script( GetLoadedScriptOrNull(aCx, aReferencingPrivate)); JS::Rooted specifierString( aCx, JS::GetModuleRequestSpecifier(aCx, aModuleRequest)); if (!specifierString) { return nullptr; } // Let url be the result of resolving a module specifier given referencing // module script and specifier. nsAutoJSString string; if (!string.init(aCx, specifierString)) { return nullptr; } RefPtr loader = GetCurrentModuleLoader(aCx); if (!loader) { return nullptr; } auto result = loader->ResolveModuleSpecifier(script, string); // This cannot fail because resolving a module specifier must have been // previously successful with these same two arguments. MOZ_ASSERT(result.isOk()); nsCOMPtr uri = result.unwrap(); MOZ_ASSERT(uri, "Failed to resolve previously-resolved module specifier"); // Let resolved module script be moduleMap[url]. (This entry must exist for // us to have gotten to this point.) ModuleScript* ms = loader->GetFetchedModule(uri); MOZ_ASSERT(ms, "Resolved module not found in module map"); MOZ_ASSERT(!ms->HasParseError()); MOZ_ASSERT(ms->ModuleRecord()); module.set(ms->ModuleRecord()); } return module; } // static bool ModuleLoaderBase::ImportMetaResolve(JSContext* cx, unsigned argc, Value* vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedValue modulePrivate( cx, js::GetFunctionNativeReserved(&args.callee(), ModulePrivateSlot)); // https://html.spec.whatwg.org/#hostgetimportmetaproperties // Step 4.1. Set specifier to ? ToString(specifier). // // https://tc39.es/ecma262/#sec-tostring RootedValue v(cx, args.get(ImportMetaResolveSpecifierArg)); RootedString specifier(cx, JS::ToString(cx, v)); if (!specifier) { return false; } // Step 4.2, 4.3 are implemented in ImportMetaResolveImpl. RootedString url(cx, ImportMetaResolveImpl(cx, modulePrivate, specifier)); if (!url) { return false; } // Step 4.4. Return the serialization of url. args.rval().setString(url); return true; } // static JSString* ModuleLoaderBase::ImportMetaResolveImpl( JSContext* aCx, JS::Handle aReferencingPrivate, JS::Handle aSpecifier) { RootedString urlString(aCx); { // ModuleScript should only live in this block, otherwise it will be a GC // hazard RefPtr script = static_cast(aReferencingPrivate.toPrivate()); MOZ_ASSERT(script->IsModuleScript()); MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) == aReferencingPrivate); RefPtr loader = GetCurrentModuleLoader(aCx); if (!loader) { return nullptr; } nsAutoJSString specifier; if (!specifier.init(aCx, aSpecifier)) { return nullptr; } auto result = loader->ResolveModuleSpecifier(script, specifier); if (result.isErr()) { JS::Rooted error(aCx); nsresult rv = loader->HandleResolveFailure( aCx, script, specifier, result.unwrapErr(), 0, JS::ColumnNumberOneOrigin(), &error); if (NS_FAILED(rv)) { JS_ReportOutOfMemory(aCx); return nullptr; } JS_SetPendingException(aCx, error); return nullptr; } nsCOMPtr uri = result.unwrap(); nsAutoCString url; MOZ_ALWAYS_SUCCEEDS(uri->GetAsciiSpec(url)); urlString.set(JS_NewStringCopyZ(aCx, url.get())); } return urlString; } // static bool ModuleLoaderBase::HostPopulateImportMeta( JSContext* aCx, JS::Handle aReferencingPrivate, JS::Handle aMetaObject) { RefPtr script = static_cast(aReferencingPrivate.toPrivate()); MOZ_ASSERT(script->IsModuleScript()); MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) == aReferencingPrivate); nsAutoCString url; MOZ_DIAGNOSTIC_ASSERT(script->BaseURL()); MOZ_ALWAYS_SUCCEEDS(script->BaseURL()->GetAsciiSpec(url)); JS::Rooted urlString(aCx, JS_NewStringCopyZ(aCx, url.get())); if (!urlString) { JS_ReportOutOfMemory(aCx); return false; } // https://html.spec.whatwg.org/#import-meta-url if (!JS_DefineProperty(aCx, aMetaObject, "url", urlString, JSPROP_ENUMERATE)) { return false; } // https://html.spec.whatwg.org/#import-meta-resolve // Define 'resolve' function on the import.meta object. JSFunction* resolveFunc = js::DefineFunctionWithReserved( aCx, aMetaObject, "resolve", ImportMetaResolve, ImportMetaResolveNumArgs, JSPROP_ENUMERATE); if (!resolveFunc) { return false; } // Store the 'active script' of the meta object into the function slot. // https://html.spec.whatwg.org/#active-script RootedObject resolveFuncObj(aCx, JS_GetFunctionObject(resolveFunc)); js::SetFunctionNativeReserved(resolveFuncObj, ModulePrivateSlot, aReferencingPrivate); return true; } // static bool ModuleLoaderBase::HostImportModuleDynamically( JSContext* aCx, JS::Handle aReferencingPrivate, JS::Handle aModuleRequest, JS::Handle aPromise) { MOZ_DIAGNOSTIC_ASSERT(aModuleRequest); MOZ_DIAGNOSTIC_ASSERT(aPromise); RefPtr script(GetLoadedScriptOrNull(aCx, aReferencingPrivate)); JS::Rooted specifierString( aCx, JS::GetModuleRequestSpecifier(aCx, aModuleRequest)); if (!specifierString) { return false; } // Attempt to resolve the module specifier. nsAutoJSString specifier; if (!specifier.init(aCx, specifierString)) { return false; } RefPtr loader = GetCurrentModuleLoader(aCx); if (!loader) { return false; } auto result = loader->ResolveModuleSpecifier(script, specifier); if (result.isErr()) { JS::Rooted error(aCx); nsresult rv = loader->HandleResolveFailure(aCx, script, specifier, result.unwrapErr(), 0, JS::ColumnNumberOneOrigin(), &error); if (NS_FAILED(rv)) { JS_ReportOutOfMemory(aCx); return false; } JS_SetPendingException(aCx, error); return false; } // Create a new top-level load request. nsCOMPtr uri = result.unwrap(); RefPtr request = loader->CreateDynamicImport(aCx, uri, script, specifierString, aPromise); if (!request) { // Throws TypeError if CreateDynamicImport returns nullptr. JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr, JSMSG_DYNAMIC_IMPORT_NOT_SUPPORTED); return false; } nsresult rv = loader->StartDynamicImport(request); if (NS_SUCCEEDED(rv)) { loader->OnDynamicImportStarted(request); } return true; } AutoOverrideModuleLoader::AutoOverrideModuleLoader(ModuleLoaderBase* aTarget, ModuleLoaderBase* aLoader) : mTarget(aTarget) { mTarget->SetOverride(aLoader); } AutoOverrideModuleLoader::~AutoOverrideModuleLoader() { mTarget->ResetOverride(); } void ModuleLoaderBase::SetOverride(ModuleLoaderBase* aLoader) { MOZ_ASSERT(!mOverriddenBy); MOZ_ASSERT(!aLoader->mOverriddenBy); MOZ_ASSERT(mGlobalObject == aLoader->mGlobalObject); mOverriddenBy = aLoader; } bool ModuleLoaderBase::IsOverridden() { return !!mOverriddenBy; } bool ModuleLoaderBase::IsOverriddenBy(ModuleLoaderBase* aLoader) { return mOverriddenBy == aLoader; } void ModuleLoaderBase::ResetOverride() { MOZ_ASSERT(mOverriddenBy); mOverriddenBy = nullptr; } // static ModuleLoaderBase* ModuleLoaderBase::GetCurrentModuleLoader(JSContext* aCx) { auto reportError = mozilla::MakeScopeExit([aCx]() { JS_ReportErrorASCII(aCx, "No ScriptLoader found for the current context"); }); JS::Rooted object(aCx, JS::CurrentGlobalOrNull(aCx)); if (!object) { return nullptr; } nsIGlobalObject* global = xpc::NativeGlobal(object); if (!global) { return nullptr; } ModuleLoaderBase* loader = global->GetModuleLoader(aCx); if (!loader) { return nullptr; } MOZ_ASSERT(loader->mGlobalObject == global); reportError.release(); if (loader->mOverriddenBy) { MOZ_ASSERT(loader->mOverriddenBy->mGlobalObject == global); return loader->mOverriddenBy; } return loader; } // static LoadedScript* ModuleLoaderBase::GetLoadedScriptOrNull( JSContext* aCx, JS::Handle aReferencingPrivate) { if (aReferencingPrivate.isUndefined()) { return nullptr; } auto* script = static_cast(aReferencingPrivate.toPrivate()); MOZ_ASSERT_IF( script->IsModuleScript(), JS::GetModulePrivate(script->AsModuleScript()->ModuleRecord()) == aReferencingPrivate); return script; } JS::Value PrivateFromLoadedScript(LoadedScript* aScript) { if (!aScript) { return JS::UndefinedValue(); } return JS::PrivateValue(aScript); } nsresult ModuleLoaderBase::StartModuleLoad(ModuleLoadRequest* aRequest) { return StartOrRestartModuleLoad(aRequest, RestartRequest::No); } nsresult ModuleLoaderBase::RestartModuleLoad(ModuleLoadRequest* aRequest) { return StartOrRestartModuleLoad(aRequest, RestartRequest::Yes); } nsresult ModuleLoaderBase::StartOrRestartModuleLoad(ModuleLoadRequest* aRequest, RestartRequest aRestart) { MOZ_ASSERT(aRequest->mLoader == this); MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsPendingFetchingError()); aRequest->SetUnknownDataType(); // If we're restarting the request, the module should already be in the // "fetching" map. MOZ_ASSERT_IF(aRestart == RestartRequest::Yes, IsModuleFetching(aRequest->mURI)); // Check with the derived class whether we should load this module. nsresult rv = NS_OK; if (!CanStartLoad(aRequest, &rv)) { return rv; } // Check whether the module has been fetched or is currently being fetched, // and if so wait for it rather than starting a new fetch. ModuleLoadRequest* request = aRequest->AsModuleRequest(); if (aRestart == RestartRequest::No && ModuleMapContainsURL(request->mURI)) { LOG(("ScriptLoadRequest (%p): Waiting for module fetch", aRequest)); WaitForModuleFetch(request); return NS_OK; } rv = StartFetch(aRequest); NS_ENSURE_SUCCESS(rv, rv); // We successfully started fetching a module so put its URL in the module // map and mark it as fetching. if (aRestart == RestartRequest::No) { SetModuleFetchStarted(aRequest->AsModuleRequest()); } return NS_OK; } bool ModuleLoaderBase::ModuleMapContainsURL(nsIURI* aURL) const { return IsModuleFetching(aURL) || IsModuleFetched(aURL); } bool ModuleLoaderBase::IsModuleFetching(nsIURI* aURL) const { return mFetchingModules.Contains(aURL); } bool ModuleLoaderBase::IsModuleFetched(nsIURI* aURL) const { return mFetchedModules.Contains(aURL); } nsresult ModuleLoaderBase::GetFetchedModuleURLs(nsTArray& aURLs) { for (const auto& entry : mFetchedModules) { nsIURI* uri = entry.GetData()->BaseURL(); nsAutoCString spec; nsresult rv = uri->GetSpec(spec); NS_ENSURE_SUCCESS(rv, rv); aURLs.AppendElement(spec); } return NS_OK; } void ModuleLoaderBase::SetModuleFetchStarted(ModuleLoadRequest* aRequest) { // Update the module map to indicate that a module is currently being fetched. MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsPendingFetchingError()); MOZ_ASSERT(!ModuleMapContainsURL(aRequest->mURI)); mFetchingModules.InsertOrUpdate(aRequest->mURI, nullptr); } void ModuleLoaderBase::SetModuleFetchFinishedAndResumeWaitingRequests( ModuleLoadRequest* aRequest, nsresult aResult) { // Update module map with the result of fetching a single module script. // // If any requests for the same URL are waiting on this one to complete, call // ModuleLoaded or LoadFailed to resume or fail them as appropriate. MOZ_ASSERT(aRequest->mLoader == this); LOG( ("ScriptLoadRequest (%p): Module fetch finished (script == %p, result == " "%u)", aRequest, aRequest->mModuleScript.get(), unsigned(aResult))); RefPtr waitingRequests; if (!mFetchingModules.Remove(aRequest->mURI, getter_AddRefs(waitingRequests))) { LOG( ("ScriptLoadRequest (%p): Key not found in mFetchingModules, " "assuming we have an inline module or have finished fetching already", aRequest)); return; } RefPtr moduleScript(aRequest->mModuleScript); MOZ_ASSERT(NS_FAILED(aResult) == !moduleScript); mFetchedModules.InsertOrUpdate(aRequest->mURI, RefPtr{moduleScript}); if (waitingRequests) { LOG(("ScriptLoadRequest (%p): Resuming waiting requests", aRequest)); ResumeWaitingRequests(waitingRequests, bool(moduleScript)); } } void ModuleLoaderBase::ResumeWaitingRequests(WaitingRequests* aWaitingRequests, bool aSuccess) { for (ModuleLoadRequest* request : aWaitingRequests->mWaiting) { ResumeWaitingRequest(request, aSuccess); } } void ModuleLoaderBase::ResumeWaitingRequest(ModuleLoadRequest* aRequest, bool aSuccess) { if (aSuccess) { aRequest->ModuleLoaded(); } else { aRequest->LoadFailed(); } } void ModuleLoaderBase::WaitForModuleFetch(ModuleLoadRequest* aRequest) { nsIURI* uri = aRequest->mURI; MOZ_ASSERT(ModuleMapContainsURL(uri)); if (auto entry = mFetchingModules.Lookup(uri)) { RefPtr waitingRequests = entry.Data(); if (!waitingRequests) { waitingRequests = new WaitingRequests(); mFetchingModules.InsertOrUpdate(uri, waitingRequests); } waitingRequests->mWaiting.AppendElement(aRequest); return; } RefPtr ms; MOZ_ALWAYS_TRUE(mFetchedModules.Get(uri, getter_AddRefs(ms))); ResumeWaitingRequest(aRequest, bool(ms)); } ModuleScript* ModuleLoaderBase::GetFetchedModule(nsIURI* aURL) const { if (LOG_ENABLED()) { nsAutoCString url; aURL->GetAsciiSpec(url); LOG(("GetFetchedModule %s", url.get())); } bool found; ModuleScript* ms = mFetchedModules.GetWeak(aURL, &found); MOZ_ASSERT(found); return ms; } nsresult ModuleLoaderBase::OnFetchComplete(ModuleLoadRequest* aRequest, nsresult aRv) { MOZ_ASSERT(aRequest->mLoader == this); MOZ_ASSERT(!aRequest->mModuleScript); nsresult rv = aRv; if (NS_SUCCEEDED(rv)) { rv = CreateModuleScript(aRequest); // If a module script was created, it should either have a module record // object or a parse error. if (ModuleScript* ms = aRequest->mModuleScript) { MOZ_DIAGNOSTIC_ASSERT(bool(ms->ModuleRecord()) != ms->HasParseError()); } aRequest->ClearScriptSource(); if (NS_FAILED(rv)) { aRequest->LoadFailed(); return rv; } } MOZ_ASSERT(NS_SUCCEEDED(rv) == bool(aRequest->mModuleScript)); SetModuleFetchFinishedAndResumeWaitingRequests(aRequest, rv); if (!aRequest->IsErrored()) { StartFetchingModuleDependencies(aRequest); } return NS_OK; } nsresult ModuleLoaderBase::CreateModuleScript(ModuleLoadRequest* aRequest) { MOZ_ASSERT(!aRequest->mModuleScript); MOZ_ASSERT(aRequest->mBaseURL); LOG(("ScriptLoadRequest (%p): Create module script", aRequest)); AutoJSAPI jsapi; if (!jsapi.Init(mGlobalObject)) { return NS_ERROR_FAILURE; } nsresult rv; { JSContext* cx = jsapi.cx(); JS::Rooted module(cx); JS::CompileOptions options(cx); JS::RootedScript introductionScript(cx); rv = mLoader->FillCompileOptionsForRequest(cx, aRequest, &options, &introductionScript); if (NS_SUCCEEDED(rv)) { JS::Rooted global(cx, mGlobalObject->GetGlobalJSObject()); rv = CompileFetchedModule(cx, global, options, aRequest, &module); } MOZ_DIAGNOSTIC_ASSERT(NS_SUCCEEDED(rv) == (module != nullptr)); if (module) { JS::RootedValue privateValue(cx); JS::RootedScript moduleScript(cx, JS::GetModuleScript(module)); JS::InstantiateOptions instantiateOptions(options); if (!JS::UpdateDebugMetadata(cx, moduleScript, instantiateOptions, privateValue, nullptr, introductionScript, nullptr)) { return NS_ERROR_OUT_OF_MEMORY; } } MOZ_ASSERT(aRequest->mLoadedScript->IsModuleScript()); MOZ_ASSERT(aRequest->mLoadedScript->GetFetchOptions() == aRequest->mFetchOptions); MOZ_ASSERT(aRequest->mLoadedScript->GetURI() == aRequest->mURI); aRequest->mLoadedScript->SetBaseURL(aRequest->mBaseURL); RefPtr moduleScript = aRequest->mLoadedScript->AsModuleScript(); aRequest->mModuleScript = moduleScript; if (!module) { LOG(("ScriptLoadRequest (%p): compilation failed (%d)", aRequest, unsigned(rv))); JS::Rooted error(cx); if (!jsapi.HasException() || !jsapi.StealException(&error) || error.isUndefined()) { aRequest->mModuleScript = nullptr; return NS_ERROR_FAILURE; } moduleScript->SetParseError(error); aRequest->ModuleErrored(); return NS_OK; } moduleScript->SetModuleRecord(module); // Validate requested modules and treat failure to resolve module specifiers // the same as a parse error. rv = ResolveRequestedModules(aRequest, nullptr); if (NS_FAILED(rv)) { if (!aRequest->IsErrored()) { aRequest->mModuleScript = nullptr; return rv; } aRequest->ModuleErrored(); return NS_OK; } } LOG(("ScriptLoadRequest (%p): module script == %p", aRequest, aRequest->mModuleScript.get())); return rv; } nsresult ModuleLoaderBase::GetResolveFailureMessage(ResolveError aError, const nsAString& aSpecifier, nsAString& aResult) { AutoTArray errorParams; errorParams.AppendElement(aSpecifier); nsresult rv = nsContentUtils::FormatLocalizedString( nsContentUtils::eDOM_PROPERTIES, ResolveErrorInfo::GetString(aError), errorParams, aResult); NS_ENSURE_SUCCESS(rv, rv); return NS_OK; } nsresult ModuleLoaderBase::HandleResolveFailure( JSContext* aCx, LoadedScript* aScript, const nsAString& aSpecifier, ResolveError aError, uint32_t aLineNumber, JS::ColumnNumberOneOrigin aColumnNumber, JS::MutableHandle aErrorOut) { JS::Rooted filename(aCx); if (aScript) { nsAutoCString url; aScript->BaseURL()->GetAsciiSpec(url); filename = JS_NewStringCopyZ(aCx, url.get()); } else { filename = JS_NewStringCopyZ(aCx, "(unknown)"); } if (!filename) { return NS_ERROR_OUT_OF_MEMORY; } nsAutoString errorText; nsresult rv = GetResolveFailureMessage(aError, aSpecifier, errorText); NS_ENSURE_SUCCESS(rv, rv); JS::Rooted string(aCx, JS_NewUCStringCopyZ(aCx, errorText.get())); if (!string) { return NS_ERROR_OUT_OF_MEMORY; } if (!JS::CreateError(aCx, JSEXN_TYPEERR, nullptr, filename, aLineNumber, aColumnNumber, nullptr, string, JS::NothingHandleValue, aErrorOut)) { return NS_ERROR_OUT_OF_MEMORY; } return NS_OK; } ResolveResult ModuleLoaderBase::ResolveModuleSpecifier( LoadedScript* aScript, const nsAString& aSpecifier) { // Import Maps are not supported on workers/worklets. // See https://github.com/WICG/import-maps/issues/2 MOZ_ASSERT_IF(!NS_IsMainThread(), mImportMap == nullptr); // Forward to the updated 'Resolve a module specifier' algorithm defined in // the Import Maps spec. return ImportMap::ResolveModuleSpecifier(mImportMap.get(), mLoader, aScript, aSpecifier); } nsresult ModuleLoaderBase::ResolveRequestedModules( ModuleLoadRequest* aRequest, nsCOMArray* aUrlsOut) { ModuleScript* ms = aRequest->mModuleScript; AutoJSAPI jsapi; if (!jsapi.Init(mGlobalObject)) { return NS_ERROR_FAILURE; } JSContext* cx = jsapi.cx(); JS::Rooted moduleRecord(cx, ms->ModuleRecord()); uint32_t length = JS::GetRequestedModulesCount(cx, moduleRecord); for (uint32_t i = 0; i < length; i++) { JS::Rooted str( cx, JS::GetRequestedModuleSpecifier(cx, moduleRecord, i)); MOZ_ASSERT(str); nsAutoJSString specifier; if (!specifier.init(cx, str)) { return NS_ERROR_FAILURE; } // Let url be the result of resolving a module specifier given module script // and requested. ModuleLoaderBase* loader = aRequest->mLoader; auto result = loader->ResolveModuleSpecifier(ms, specifier); if (result.isErr()) { uint32_t lineNumber = 0; JS::ColumnNumberOneOrigin columnNumber; JS::GetRequestedModuleSourcePos(cx, moduleRecord, i, &lineNumber, &columnNumber); JS::Rooted error(cx); nsresult rv = loader->HandleResolveFailure(cx, ms, specifier, result.unwrapErr(), lineNumber, columnNumber, &error); NS_ENSURE_SUCCESS(rv, rv); ms->SetParseError(error); return NS_ERROR_FAILURE; } nsCOMPtr uri = result.unwrap(); if (aUrlsOut) { aUrlsOut->AppendElement(uri.forget()); } } return NS_OK; } void ModuleLoaderBase::StartFetchingModuleDependencies( ModuleLoadRequest* aRequest) { LOG(("ScriptLoadRequest (%p): Start fetching module dependencies", aRequest)); if (aRequest->IsCanceled()) { return; } MOZ_ASSERT(aRequest->mModuleScript); MOZ_ASSERT(!aRequest->mModuleScript->HasParseError()); MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsCompiling()); auto visitedSet = aRequest->mVisitedSet; MOZ_ASSERT(visitedSet->Contains(aRequest->mURI)); aRequest->mState = ModuleLoadRequest::State::LoadingImports; nsCOMArray urls; nsresult rv = ResolveRequestedModules(aRequest, &urls); if (NS_FAILED(rv)) { aRequest->mModuleScript = nullptr; aRequest->ModuleErrored(); return; } // Remove already visited URLs from the list. Put unvisited URLs into the // visited set. int32_t i = 0; while (i < urls.Count()) { nsIURI* url = urls[i]; if (visitedSet->Contains(url)) { urls.RemoveObjectAt(i); } else { visitedSet->PutEntry(url); i++; } } if (urls.Count() == 0) { // There are no descendants to load so this request is ready. aRequest->DependenciesLoaded(); return; } MOZ_ASSERT(aRequest->mAwaitingImports == 0); aRequest->mAwaitingImports = urls.Count(); // For each url in urls, fetch a module script graph given url, module // script's CORS setting, and module script's settings object. for (auto* url : urls) { StartFetchingModuleAndDependencies(aRequest, url); } } void ModuleLoaderBase::StartFetchingModuleAndDependencies( ModuleLoadRequest* aParent, nsIURI* aURI) { MOZ_ASSERT(aURI); RefPtr childRequest = CreateStaticImport(aURI, aParent); aParent->mImports.AppendElement(childRequest); if (LOG_ENABLED()) { nsAutoCString url1; aParent->mURI->GetAsciiSpec(url1); nsAutoCString url2; aURI->GetAsciiSpec(url2); LOG(("ScriptLoadRequest (%p): Start fetching dependency %p", aParent, childRequest.get())); LOG(("StartFetchingModuleAndDependencies \"%s\" -> \"%s\"", url1.get(), url2.get())); } MOZ_ASSERT(!childRequest->mWaitingParentRequest); childRequest->mWaitingParentRequest = aParent; nsresult rv = StartModuleLoad(childRequest); if (NS_FAILED(rv)) { MOZ_ASSERT(!childRequest->mModuleScript); LOG(("ScriptLoadRequest (%p): rejecting %p", aParent, childRequest.get())); mLoader->ReportErrorToConsole(childRequest, rv); childRequest->LoadFailed(); } } void ModuleLoadRequest::ChildLoadComplete(bool aSuccess) { RefPtr parent = mWaitingParentRequest; MOZ_ASSERT(parent); MOZ_ASSERT(parent->mAwaitingImports != 0); mWaitingParentRequest = nullptr; parent->mAwaitingImports--; if (parent->IsFinished()) { MOZ_ASSERT_IF(!aSuccess, parent->IsErrored()); return; } if (!aSuccess) { parent->ModuleErrored(); } else if (parent->mAwaitingImports == 0) { parent->DependenciesLoaded(); } } nsresult ModuleLoaderBase::StartDynamicImport(ModuleLoadRequest* aRequest) { MOZ_ASSERT(aRequest->mLoader == this); LOG(("ScriptLoadRequest (%p): Start dynamic import", aRequest)); mDynamicImportRequests.AppendElement(aRequest); nsresult rv = StartModuleLoad(aRequest); if (NS_FAILED(rv)) { mLoader->ReportErrorToConsole(aRequest, rv); FinishDynamicImportAndReject(aRequest, rv); } return rv; } void ModuleLoaderBase::FinishDynamicImportAndReject(ModuleLoadRequest* aRequest, nsresult aResult) { AutoJSAPI jsapi; MOZ_ASSERT(NS_FAILED(aResult)); if (!jsapi.Init(mGlobalObject)) { return; } FinishDynamicImport(jsapi.cx(), aRequest, aResult, nullptr); } /* static */ void ModuleLoaderBase::FinishDynamicImport( JSContext* aCx, ModuleLoadRequest* aRequest, nsresult aResult, JS::Handle aEvaluationPromise) { LOG(("ScriptLoadRequest (%p): Finish dynamic import %x %d", aRequest, unsigned(aResult), JS_IsExceptionPending(aCx))); MOZ_ASSERT(GetCurrentModuleLoader(aCx) == aRequest->mLoader); // If aResult is a failed result, we don't have an EvaluationPromise. If it // succeeded, evaluationPromise may still be null, but in this case it will // be handled by rejecting the dynamic module import promise in the JSAPI. MOZ_ASSERT_IF(NS_FAILED(aResult), !aEvaluationPromise); // Complete the dynamic import, report failures indicated by aResult or as a // pending exception on the context. if (!aRequest->mDynamicPromise) { // Import has already been completed. return; } if (NS_FAILED(aResult) && aResult != NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW_UNCATCHABLE) { MOZ_ASSERT(!JS_IsExceptionPending(aCx)); nsAutoCString url; aRequest->mURI->GetSpec(url); JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr, JSMSG_DYNAMIC_IMPORT_FAILED, url.get()); } JS::Rooted referencingScript( aCx, PrivateFromLoadedScript(aRequest->mDynamicReferencingScript)); JS::Rooted specifier(aCx, aRequest->mDynamicSpecifier); JS::Rooted promise(aCx, aRequest->mDynamicPromise); JS::Rooted moduleRequest(aCx, JS::CreateModuleRequest(aCx, specifier)); JS::FinishDynamicModuleImport(aCx, aEvaluationPromise, referencingScript, moduleRequest, promise); // FinishDynamicModuleImport clears any pending exception. MOZ_ASSERT(!JS_IsExceptionPending(aCx)); aRequest->ClearDynamicImport(); } ModuleLoaderBase::ModuleLoaderBase(ScriptLoaderInterface* aLoader, nsIGlobalObject* aGlobalObject) : mGlobalObject(aGlobalObject), mLoader(aLoader) { MOZ_ASSERT(mGlobalObject); MOZ_ASSERT(mLoader); EnsureModuleHooksInitialized(); } ModuleLoaderBase::~ModuleLoaderBase() { mDynamicImportRequests.CancelRequestsAndClear(); LOG(("ModuleLoaderBase::~ModuleLoaderBase %p", this)); } void ModuleLoaderBase::Shutdown() { CancelAndClearDynamicImports(); for (const auto& entry : mFetchingModules) { RefPtr waitingRequests(entry.GetData()); if (waitingRequests) { ResumeWaitingRequests(waitingRequests, false); } } for (const auto& entry : mFetchedModules) { if (entry.GetData()) { entry.GetData()->Shutdown(); } } mFetchingModules.Clear(); mFetchedModules.Clear(); mGlobalObject = nullptr; mLoader = nullptr; } bool ModuleLoaderBase::HasFetchingModules() const { return !mFetchingModules.IsEmpty(); } bool ModuleLoaderBase::HasPendingDynamicImports() const { return !mDynamicImportRequests.isEmpty(); } void ModuleLoaderBase::CancelDynamicImport(ModuleLoadRequest* aRequest, nsresult aResult) { MOZ_ASSERT(aRequest->mLoader == this); RefPtr req = mDynamicImportRequests.Steal(aRequest); if (!aRequest->IsCanceled()) { aRequest->Cancel(); // FinishDynamicImport must happen exactly once for each dynamic import // request. If the load is aborted we do it when we remove the request // from mDynamicImportRequests. FinishDynamicImportAndReject(aRequest, aResult); } } void ModuleLoaderBase::RemoveDynamicImport(ModuleLoadRequest* aRequest) { MOZ_ASSERT(aRequest->IsDynamicImport()); mDynamicImportRequests.Remove(aRequest); } #ifdef DEBUG bool ModuleLoaderBase::HasDynamicImport( const ModuleLoadRequest* aRequest) const { MOZ_ASSERT(aRequest->mLoader == this); return mDynamicImportRequests.Contains( const_cast(aRequest)); } #endif JS::Value ModuleLoaderBase::FindFirstParseError(ModuleLoadRequest* aRequest) { MOZ_ASSERT(aRequest); ModuleScript* moduleScript = aRequest->mModuleScript; MOZ_ASSERT(moduleScript); if (moduleScript->HasParseError()) { return moduleScript->ParseError(); } for (ModuleLoadRequest* childRequest : aRequest->mImports) { JS::Value error = FindFirstParseError(childRequest); if (!error.isUndefined()) { return error; } } return JS::UndefinedValue(); } bool ModuleLoaderBase::InstantiateModuleGraph(ModuleLoadRequest* aRequest) { // Instantiate a top-level module and record any error. MOZ_ASSERT(aRequest); MOZ_ASSERT(aRequest->mLoader == this); MOZ_ASSERT(aRequest->IsTopLevel()); LOG(("ScriptLoadRequest (%p): Instantiate module graph", aRequest)); AUTO_PROFILER_LABEL("ModuleLoaderBase::InstantiateModuleGraph", JS); ModuleScript* moduleScript = aRequest->mModuleScript; MOZ_ASSERT(moduleScript); JS::Value parseError = FindFirstParseError(aRequest); if (!parseError.isUndefined()) { moduleScript->SetErrorToRethrow(parseError); LOG(("ScriptLoadRequest (%p): found parse error", aRequest)); return true; } MOZ_ASSERT(moduleScript->ModuleRecord()); AutoJSAPI jsapi; if (NS_WARN_IF(!jsapi.Init(mGlobalObject))) { return false; } JS::Rooted module(jsapi.cx(), moduleScript->ModuleRecord()); if (!xpc::Scriptability::AllowedIfExists(module)) { return true; } if (!JS::ModuleLink(jsapi.cx(), module)) { LOG(("ScriptLoadRequest (%p): Instantiate failed", aRequest)); MOZ_ASSERT(jsapi.HasException()); JS::RootedValue exception(jsapi.cx()); if (!jsapi.StealException(&exception)) { return false; } MOZ_ASSERT(!exception.isUndefined()); moduleScript->SetErrorToRethrow(exception); } return true; } nsresult ModuleLoaderBase::InitDebuggerDataForModuleGraph( JSContext* aCx, ModuleLoadRequest* aRequest) { // JS scripts can be associated with a DOM element for use by the debugger, // but preloading can cause scripts to be compiled before DOM script element // nodes have been created. This method ensures that this association takes // place before the first time a module script is run. MOZ_ASSERT(aRequest); ModuleScript* moduleScript = aRequest->mModuleScript; if (moduleScript->DebuggerDataInitialized()) { return NS_OK; } for (ModuleLoadRequest* childRequest : aRequest->mImports) { nsresult rv = InitDebuggerDataForModuleGraph(aCx, childRequest); NS_ENSURE_SUCCESS(rv, rv); } JS::Rooted module(aCx, moduleScript->ModuleRecord()); MOZ_ASSERT(module); // The script is now ready to be exposed to the debugger. JS::Rooted script(aCx, JS::GetModuleScript(module)); JS::ExposeScriptToDebugger(aCx, script); moduleScript->SetDebuggerDataInitialized(); return NS_OK; } void ModuleLoaderBase::ProcessDynamicImport(ModuleLoadRequest* aRequest) { if (!aRequest->mModuleScript) { FinishDynamicImportAndReject(aRequest, NS_ERROR_FAILURE); return; } InstantiateAndEvaluateDynamicImport(aRequest); } void ModuleLoaderBase::InstantiateAndEvaluateDynamicImport( ModuleLoadRequest* aRequest) { MOZ_ASSERT(aRequest->mModuleScript); if (!InstantiateModuleGraph(aRequest)) { aRequest->mModuleScript = nullptr; } nsresult rv = NS_ERROR_FAILURE; if (aRequest->mModuleScript) { rv = EvaluateModule(aRequest); } if (NS_FAILED(rv)) { FinishDynamicImportAndReject(aRequest, rv); } } nsresult ModuleLoaderBase::EvaluateModule(ModuleLoadRequest* aRequest) { MOZ_ASSERT(aRequest->mLoader == this); mozilla::nsAutoMicroTask mt; mozilla::dom::AutoEntryScript aes(mGlobalObject, "EvaluateModule", NS_IsMainThread()); return EvaluateModuleInContext(aes.cx(), aRequest, JS::ReportModuleErrorsAsync); } nsresult ModuleLoaderBase::EvaluateModuleInContext( JSContext* aCx, ModuleLoadRequest* aRequest, JS::ModuleErrorBehaviour errorBehaviour) { MOZ_ASSERT(aRequest->mLoader == this); MOZ_ASSERT_IF(!mGlobalObject->GetModuleLoader(aCx)->IsOverridden(), mGlobalObject->GetModuleLoader(aCx) == this); MOZ_ASSERT_IF(mGlobalObject->GetModuleLoader(aCx)->IsOverridden(), mGlobalObject->GetModuleLoader(aCx)->IsOverriddenBy(this)); AUTO_PROFILER_LABEL("ModuleLoaderBase::EvaluateModule", JS); nsAutoCString profilerLabelString; if (aRequest->HasScriptLoadContext()) { aRequest->GetScriptLoadContext()->GetProfilerLabel(profilerLabelString); } LOG(("ScriptLoadRequest (%p): Evaluate Module", aRequest)); AUTO_PROFILER_MARKER_TEXT("ModuleEvaluation", JS, MarkerInnerWindowIdFromJSContext(aCx), profilerLabelString); ModuleLoadRequest* request = aRequest->AsModuleRequest(); MOZ_ASSERT(request->mModuleScript); MOZ_ASSERT_IF(request->HasScriptLoadContext(), !request->GetScriptLoadContext()->mCompileOrDecodeTask); ModuleScript* moduleScript = request->mModuleScript; if (moduleScript->HasErrorToRethrow()) { LOG(("ScriptLoadRequest (%p): module has error to rethrow", aRequest)); JS::Rooted error(aCx, moduleScript->ErrorToRethrow()); JS_SetPendingException(aCx, error); // For a dynamic import, the promise is rejected. Otherwise an error // is either reported by AutoEntryScript. if (request->IsDynamicImport()) { FinishDynamicImport(aCx, request, NS_OK, nullptr); } return NS_OK; } JS::Rooted module(aCx, moduleScript->ModuleRecord()); MOZ_ASSERT(module); MOZ_ASSERT(CurrentGlobalOrNull(aCx) == GetNonCCWObjectGlobal(module)); if (!xpc::Scriptability::AllowedIfExists(module)) { return NS_OK; } nsresult rv = InitDebuggerDataForModuleGraph(aCx, request); NS_ENSURE_SUCCESS(rv, rv); if (request->HasScriptLoadContext()) { TRACE_FOR_TEST(aRequest->GetScriptLoadContext()->GetScriptElement(), "scriptloader_evaluate_module"); } JS::Rooted rval(aCx); mLoader->MaybePrepareModuleForBytecodeEncodingBeforeExecute(aCx, request); bool ok = JS::ModuleEvaluate(aCx, module, &rval); // ModuleEvaluate will usually set a pending exception if it returns false, // unless the user cancels execution. MOZ_ASSERT_IF(ok, !JS_IsExceptionPending(aCx)); if (!ok || IsModuleEvaluationAborted(request)) { LOG(("ScriptLoadRequest (%p): evaluation failed", aRequest)); // For a dynamic import, the promise is rejected. Otherwise an error is // reported by AutoEntryScript. rv = NS_ERROR_ABORT; } // ModuleEvaluate returns a promise unless the user cancels the execution in // which case rval will be undefined. We should treat it as a failed // evaluation, and reject appropriately. JS::Rooted evaluationPromise(aCx); if (rval.isObject()) { evaluationPromise.set(&rval.toObject()); } if (request->IsDynamicImport()) { if (NS_FAILED(rv)) { FinishDynamicImportAndReject(request, rv); } else { FinishDynamicImport(aCx, request, NS_OK, evaluationPromise); } } else { // If this is not a dynamic import, and if the promise is rejected, // the value is unwrapped from the promise value. if (!JS::ThrowOnModuleEvaluationFailure(aCx, evaluationPromise, errorBehaviour)) { LOG(("ScriptLoadRequest (%p): evaluation failed on throw", aRequest)); // For a dynamic import, the promise is rejected. Otherwise an error is // reported by AutoEntryScript. } } rv = mLoader->MaybePrepareModuleForBytecodeEncodingAfterExecute(request, NS_OK); mLoader->MaybeTriggerBytecodeEncoding(); return rv; } void ModuleLoaderBase::CancelAndClearDynamicImports() { while (ScriptLoadRequest* req = mDynamicImportRequests.getFirst()) { // This also removes the request from the list. CancelDynamicImport(req->AsModuleRequest(), NS_ERROR_ABORT); } } UniquePtr ModuleLoaderBase::ParseImportMap( ScriptLoadRequest* aRequest) { AutoJSAPI jsapi; if (!jsapi.Init(GetGlobalObject())) { return nullptr; } MOZ_ASSERT(aRequest->IsTextSource()); MaybeSourceText maybeSource; nsresult rv = aRequest->GetScriptSource(jsapi.cx(), &maybeSource, aRequest->mLoadContext.get()); if (NS_FAILED(rv)) { return nullptr; } JS::SourceText& text = maybeSource.ref>(); ReportWarningHelper warning{mLoader, aRequest}; // https://html.spec.whatwg.org/multipage/webappapis.html#create-an-import-map-parse-result // Step 2. Parse an import map string given input and baseURL, catching any // exceptions. If this threw an exception, then set result's error to rethrow // to that exception. Otherwise, set result's import map to the return value. // // https://html.spec.whatwg.org/multipage/webappapis.html#register-an-import-map // Step 1. If result's error to rethrow is not null, then report the exception // given by result's error to rethrow and return. // // Impl note: We didn't implement 'Import map parse result' from the spec, // https://html.spec.whatwg.org/multipage/webappapis.html#import-map-parse-result // As the struct has another item called 'error to rethow' to store the // exception thrown during parsing import-maps, and report that exception // while registering an import map. Currently only inline import-maps are // supported, therefore parsing and registering import-maps will be executed // consecutively. To simplify the implementation, we didn't create the 'error // to rethow' item and report the exception immediately(done in ~AutoJSAPI). return ImportMap::ParseString(jsapi.cx(), text, aRequest->mBaseURL, warning); } void ModuleLoaderBase::RegisterImportMap(UniquePtr aImportMap) { // Check for aImportMap is done in ScriptLoader. MOZ_ASSERT(aImportMap); // https://html.spec.whatwg.org/multipage/webappapis.html#register-an-import-map // The step 1(report the exception if there's an error) is done in // ParseImportMap. // // Step 2. Assert: global's import map is an empty import map. // Impl note: The default import map from the spec is an empty import map, but // from the implementation it defaults to nullptr, so we check if the global's // import map is null here. // // Also see // https://html.spec.whatwg.org/multipage/webappapis.html#empty-import-map MOZ_ASSERT(!mImportMap); // Step 3. Set global's import map to result's import map. mImportMap = std::move(aImportMap); } void ModuleLoaderBase::CopyModulesTo(ModuleLoaderBase* aDest) { MOZ_ASSERT(aDest->mFetchingModules.IsEmpty()); MOZ_ASSERT(aDest->mFetchedModules.IsEmpty()); MOZ_ASSERT(mFetchingModules.IsEmpty()); for (const auto& entry : mFetchedModules) { RefPtr moduleScript = entry.GetData(); if (!moduleScript) { continue; } aDest->mFetchedModules.InsertOrUpdate(entry.GetKey(), moduleScript); } } void ModuleLoaderBase::MoveModulesTo(ModuleLoaderBase* aDest) { MOZ_ASSERT(mFetchingModules.IsEmpty()); MOZ_ASSERT(aDest->mFetchingModules.IsEmpty()); for (const auto& entry : mFetchedModules) { RefPtr moduleScript = entry.GetData(); if (!moduleScript) { continue; } #ifdef DEBUG if (auto existingEntry = aDest->mFetchedModules.Lookup(entry.GetKey())) { MOZ_ASSERT(moduleScript == existingEntry.Data()); } #endif aDest->mFetchedModules.InsertOrUpdate(entry.GetKey(), moduleScript); } mFetchedModules.Clear(); } #undef LOG #undef LOG_ENABLED } // namespace JS::loader