Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "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::LoadingRequest
//////////////////////////////////////////////////////////////
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ModuleLoaderBase::LoadingRequest)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION(ModuleLoaderBase::LoadingRequest, mRequest, mWaiting)
NS_IMPL_CYCLE_COLLECTING_ADDREF(ModuleLoaderBase::LoadingRequest)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ModuleLoaderBase::LoadingRequest)
//////////////////////////////////////////////////////////////
// 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<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aModuleRequest) {
JS::Rooted<JSObject*> module(aCx);
{
// LoadedScript should only live in this block, otherwise it will be a GC
// hazard
RefPtr<LoadedScript> script(
GetLoadedScriptOrNull(aCx, aReferencingPrivate));
JS::Rooted<JSString*> 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<ModuleLoaderBase> 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<nsIURI> uri = result.unwrap();
MOZ_ASSERT(uri, "Failed to resolve previously-resolved module specifier");
// Let moduleType be the result of running the module type from module
// request steps given moduleRequest.
JS::ModuleType moduleType = JS::GetModuleRequestType(aCx, aModuleRequest);
// Let resolved module script be moduleMap[url]. (This entry must exist for
// us to have gotten to this point.)
ModuleScript* ms = loader->GetFetchedModule(ModuleMapKey(uri, moduleType));
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));
// Step 4.1. Set specifier to ? ToString(specifier).
//
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<JS::Value> aReferencingPrivate,
JS::Handle<JSString*> aSpecifier) {
RootedString urlString(aCx);
{
// ModuleScript should only live in this block, otherwise it will be a GC
// hazard
RefPtr<ModuleScript> script =
static_cast<ModuleScript*>(aReferencingPrivate.toPrivate());
MOZ_ASSERT(script->IsModuleScript());
MOZ_ASSERT(JS::GetModulePrivate(script->ModuleRecord()) ==
aReferencingPrivate);
RefPtr<ModuleLoaderBase> 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<JS::Value> 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<nsIURI> 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<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aMetaObject) {
RefPtr<ModuleScript> script =
static_cast<ModuleScript*>(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<JSString*> urlString(aCx, JS_NewStringCopyZ(aCx, url.get()));
if (!urlString) {
JS_ReportOutOfMemory(aCx);
return false;
}
if (!JS_DefineProperty(aCx, aMetaObject, "url", urlString,
JSPROP_ENUMERATE)) {
return false;
}
// 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.
RootedObject resolveFuncObj(aCx, JS_GetFunctionObject(resolveFunc));
js::SetFunctionNativeReserved(resolveFuncObj, ModulePrivateSlot,
aReferencingPrivate);
return true;
}
// static
bool ModuleLoaderBase::HostImportModuleDynamically(
JSContext* aCx, JS::Handle<JS::Value> aReferencingPrivate,
JS::Handle<JSObject*> aModuleRequest, JS::Handle<JSObject*> aPromise) {
MOZ_DIAGNOSTIC_ASSERT(aModuleRequest);
MOZ_DIAGNOSTIC_ASSERT(aPromise);
RefPtr<LoadedScript> script(GetLoadedScriptOrNull(aCx, aReferencingPrivate));
JS::Rooted<JSString*> 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<ModuleLoaderBase> loader = GetCurrentModuleLoader(aCx);
if (!loader) {
return false;
}
if (!loader->IsDynamicImportSupported()) {
JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr,
JSMSG_DYNAMIC_IMPORT_NOT_SUPPORTED);
return false;
}
auto result = loader->ResolveModuleSpecifier(script, specifier);
if (result.isErr()) {
JS::Rooted<JS::Value> 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;
}
// Let moduleType be the result of running the module type from module
// request steps given moduleRequest.
JS::ModuleType moduleType = JS::GetModuleRequestType(aCx, aModuleRequest);
// Create a new top-level load request.
nsCOMPtr<nsIURI> uri = result.unwrap();
RefPtr<ModuleLoadRequest> request = loader->CreateDynamicImport(
aCx, uri, moduleType, 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<JSObject*> 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<JS::Value> aReferencingPrivate) {
if (aReferencingPrivate.isUndefined()) {
return nullptr;
}
auto* script = static_cast<LoadedScript*>(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(ModuleMapKey(aRequest->mURI, aRequest->mModuleType)));
// 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(
ModuleMapKey(request->mURI, aRequest->mModuleType))) {
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(const ModuleMapKey& key) const {
return IsModuleFetching(key) || IsModuleFetched(key);
}
bool ModuleLoaderBase::IsModuleFetching(const ModuleMapKey& key) const {
return mFetchingModules.Contains(key);
}
bool ModuleLoaderBase::IsModuleFetched(const ModuleMapKey& key) const {
return mFetchedModules.Contains(key);
}
nsresult ModuleLoaderBase::GetFetchedModuleURLs(nsTArray<nsCString>& 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.
ModuleMapKey moduleMapKey(aRequest->mURI, aRequest->mModuleType);
MOZ_ASSERT(aRequest->IsFetching() || aRequest->IsPendingFetchingError());
MOZ_ASSERT(!ModuleMapContainsURL(moduleMapKey));
RefPtr<LoadingRequest> loadingRequest = new LoadingRequest();
loadingRequest->mRequest = aRequest;
mFetchingModules.InsertOrUpdate(moduleMapKey, loadingRequest);
}
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)));
ModuleMapKey moduleMapKey(aRequest->mURI, aRequest->mModuleType);
auto entry = mFetchingModules.Lookup(moduleMapKey);
if (!entry) {
LOG(
("ScriptLoadRequest (%p): Key not found in mFetchingModules, "
"assuming we have an inline module or have finished fetching already",
aRequest));
return;
}
// It's possible for a request to be cancelled and removed from the fetching
// modules map and a new request started for the same URI and added to the
// map. In this case we don't want the first cancelled request to complete the
// later request (which will cause it to fail) so we ignore it.
RefPtr<LoadingRequest> loadingRequest = entry.Data();
if (loadingRequest->mRequest != aRequest) {
MOZ_ASSERT(aRequest->IsCanceled());
LOG(
("ScriptLoadRequest (%p): Ignoring completion of cancelled request "
"that was removed from the map",
aRequest));
return;
}
MOZ_ALWAYS_TRUE(mFetchingModules.Remove(moduleMapKey));
RefPtr<ModuleScript> moduleScript(aRequest->mModuleScript);
MOZ_ASSERT(NS_FAILED(aResult) == !moduleScript);
mFetchedModules.InsertOrUpdate(moduleMapKey, RefPtr{moduleScript});
LOG(("ScriptLoadRequest (%p): Resuming waiting requests", aRequest));
MOZ_ASSERT(loadingRequest->mRequest == aRequest);
ResumeWaitingRequests(loadingRequest, bool(moduleScript));
}
void ModuleLoaderBase::ResumeWaitingRequests(LoadingRequest* aLoadingRequest,
bool aSuccess) {
for (ModuleLoadRequest* request : aLoadingRequest->mWaiting) {
ResumeWaitingRequest(request, aSuccess);
}
}
void ModuleLoaderBase::ResumeWaitingRequest(ModuleLoadRequest* aRequest,
bool aSuccess) {
if (aSuccess) {
aRequest->ModuleLoaded();
} else {
aRequest->LoadFailed();
}
}
void ModuleLoaderBase::WaitForModuleFetch(ModuleLoadRequest* aRequest) {
ModuleMapKey moduleMapKey(aRequest->mURI, aRequest->mModuleType);
MOZ_ASSERT(ModuleMapContainsURL(moduleMapKey));
if (auto entry = mFetchingModules.Lookup(moduleMapKey)) {
RefPtr<LoadingRequest> loadingRequest = entry.Data();
loadingRequest->mWaiting.AppendElement(aRequest);
return;
}
RefPtr<ModuleScript> ms;
MOZ_ALWAYS_TRUE(mFetchedModules.Get(moduleMapKey, getter_AddRefs(ms)));
ResumeWaitingRequest(aRequest, bool(ms));
}
ModuleScript* ModuleLoaderBase::GetFetchedModule(
const ModuleMapKey& moduleMapKey) const {
if (LOG_ENABLED()) {
nsAutoCString url;
moduleMapKey.mUri->GetAsciiSpec(url);
LOG(("GetFetchedModule %s", url.get()));
}
bool found;
ModuleScript* ms = mFetchedModules.GetWeak(moduleMapKey, &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 defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
// 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());
}
#endif
aRequest->ClearScriptSource();