[v18.x] backport various patches of internal refactorings for snapshot and realms

.eslintrc.js

@@ -338,6 +338,7 @@ module.exports = {
     TextEncoderStream: 'readable',
     TransformStream: 'readable',
     TransformStreamDefaultController: 'readable',
+    ShadowRealm: 'readable',
     SubtleCrypto: 'readable',
     WritableStream: 'readable',
     WritableStreamDefaultWriter: 'readable',

doc/api/cli.md

@@ -411,10 +411,18 @@ Disable experimental support for the [Fetch API][].
 
 <!-- YAML
 added: v16.6.0
- -->
+-->
 
 Use this flag to disable top-level await in REPL.
 
+### `--experimental-shadow-realm`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Use this flag to enable [ShadowRealm][] support.
+
 ### `--experimental-specifier-resolution=mode`
 
 <!-- YAML
@@ -1177,6 +1185,15 @@ in the current working directory.
 When used without `--build-snapshot`, `--snapshot-blob` specifies the
 path to the blob that will be used to restore the application state.
 
+When loading a snapshot, Node.js checks that:
+
+1. The version, architecture and platform of the running Node.js binary
+   are exactly the same as that of the binary that generates the snapshot.
+2. The V8 flags and CPU features are compatible with that of the binary
+   that generates the snapshot.
+
+If they don't match, Node.js would refuse to load the snapshot and exit with 1.
+
 ### `--test`
 
 <!-- YAML
@@ -1807,6 +1824,7 @@ Node.js options that are allowed are:
 * `--experimental-modules`
 * `--experimental-network-imports`
 * `--experimental-policy`
+* `--experimental-shadow-realm`
 * `--experimental-specifier-resolution`
 * `--experimental-top-level-await`
 * `--experimental-vm-modules`
@@ -2236,6 +2254,7 @@ done
 [OSSL_PROVIDER-legacy]: https://www.openssl.org/docs/man3.0/man7/OSSL_PROVIDER-legacy.html
 [REPL]: repl.md
 [ScriptCoverage]: https://chromedevtools.github.io/devtools-protocol/tot/Profiler#type-ScriptCoverage
+[ShadowRealm]: https://github.com/tc39/proposal-shadowrealm
 [Source Map]: https://sourcemaps.info/spec.html
 [Subresource Integrity]: https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity
 [V8 JavaScript code coverage]: https://v8project.blogspot.com/2017/12/javascript-code-coverage.html

doc/node.1

@@ -159,6 +159,9 @@ Enable experimental support for loading modules using `import` over `https:`.
 .It Fl -experimental-policy
 Use the specified file as a security policy.
 .
+.It Fl -experimental-shadow-realm
+Use this flag to enable ShadowRealm support.
+.
 .It Fl -no-experimental-fetch
 Disable experimental support for the Fetch API.
 .

lib/.eslintrc.yaml

@@ -89,6 +89,10 @@ rules:
       message: Use `const { Request } = require('internal/deps/undici/undici');` instead of the global.
     - name: Response
       message: Use `const { Response } = require('internal/deps/undici/undici');` instead of the global.
+      # ShadowRealm is not available in primordials because it can be
+      # disabled with --no-harmony-shadow-realm CLI flag.
+    - name: ShadowRealm
+      message: Use `const { ShadowRealm } = globalThis;` instead of the global.
       # SharedArrayBuffer is not available in primordials because it can be
       # disabled with --no-harmony-sharedarraybuffer CLI flag.
     - name: SharedArrayBuffer

lib/internal/perf/event_loop_utilization.js

@@ -1,13 +1,26 @@
 'use strict';
 
-const nodeTiming = require('internal/perf/nodetiming');
-
-const { now } = require('internal/perf/utils');
+const {
+  constants: {
+    NODE_PERFORMANCE_MILESTONE_LOOP_START,
+  },
+  loopIdleTime,
+  milestones,
+} = internalBinding('performance');
 
 function eventLoopUtilization(util1, util2) {
-  const ls = nodeTiming.loopStart;
+  // Get the original milestone timestamps that calculated from the beginning
+  // of the process.
+  return internalEventLoopUtilization(
+    milestones[NODE_PERFORMANCE_MILESTONE_LOOP_START] / 1e6,
+    loopIdleTime(),
+    util1,
+    util2
+  );
+}
 
-  if (ls <= 0) {
+function internalEventLoopUtilization(loopStart, loopIdleTime, util1, util2) {
+  if (loopStart <= 0) {
     return { idle: 0, active: 0, utilization: 0 };
   }
 
@@ -17,17 +30,31 @@ function eventLoopUtilization(util1, util2) {
     return { idle, active, utilization: active / (idle + active) };
   }
 
-  const idle = nodeTiming.idleTime;
-  const active = now() - ls - idle;
+  // Using process.hrtime() to get the time from the beginning of the process,
+  // and offset it by the loopStart time (which is also calculated from the
+  // beginning of the process).
+  const now = process.hrtime();
+  const active = now[0] * 1e3 + now[1] / 1e6 - loopStart - loopIdleTime;
 
   if (!util1) {
-    return { idle, active, utilization: active / (idle + active) };
+    return {
+      idle: loopIdleTime,
+      active,
+      utilization: active / (loopIdleTime + active),
+    };
   }
 
-  const idle_delta = idle - util1.idle;
-  const active_delta = active - util1.active;
-  const utilization = active_delta / (idle_delta + active_delta);
-  return { idle: idle_delta, active: active_delta, utilization };
+  const idleDelta = loopIdleTime - util1.idle;
+  const activeDelta = active - util1.active;
+  const utilization = activeDelta / (idleDelta + activeDelta);
+  return {
+    idle: idleDelta,
+    active: activeDelta,
+    utilization,
+  };
 }
 
-module.exports = eventLoopUtilization;
+module.exports = {
+  internalEventLoopUtilization,
+  eventLoopUtilization,
+};

lib/internal/perf/performance.js

@@ -35,7 +35,7 @@ const {
   setDispatchBufferFull,
 } = require('internal/perf/observe');
 
-const eventLoopUtilization = require('internal/perf/event_loop_utilization');
+const { eventLoopUtilization } = require('internal/perf/event_loop_utilization');
 const nodeTiming = require('internal/perf/nodetiming');
 const timerify = require('internal/perf/timerify');
 const { customInspectSymbol: kInspect } = require('internal/util');

lib/internal/worker.js

@@ -27,7 +27,9 @@ const {
 const EventEmitter = require('events');
 const assert = require('internal/assert');
 const path = require('path');
-const { now } = require('internal/perf/utils');
+const {
+  internalEventLoopUtilization
+} = require('internal/perf/event_loop_utilization');
 
 const errorCodes = require('internal/errors').codes;
 const {
@@ -472,28 +474,12 @@ function eventLoopUtilization(util1, util2) {
       return { idle: 0, active: 0, utilization: 0 };
   }
 
-  if (util2) {
-    const idle = util1.idle - util2.idle;
-    const active = util1.active - util2.active;
-    return { idle, active, utilization: active / (idle + active) };
-  }
-
-  const idle = this[kHandle].loopIdleTime();
-
-  // Using performance.now() here is fine since it's always the time from
-  // the beginning of the process, and is why it needs to be offset by the
-  // loopStart time (which is also calculated from the beginning of the
-  // process).
-  const active = now() - this[kLoopStartTime] - idle;
-
-  if (!util1) {
-    return { idle, active, utilization: active / (idle + active) };
-  }
-
-  const idle_delta = idle - util1.idle;
-  const active_delta = active - util1.active;
-  const utilization = active_delta / (idle_delta + active_delta);
-  return { idle: idle_delta, active: active_delta, utilization };
+  return internalEventLoopUtilization(
+    this[kLoopStartTime],
+    this[kHandle].loopIdleTime(),
+    util1,
+    util2
+  );
 }
 
 module.exports = {

node.gyp

@@ -477,6 +477,7 @@
         'src/api/hooks.cc',
         'src/api/utils.cc',
         'src/async_wrap.cc',
+        'src/base_object.cc',
         'src/cares_wrap.cc',
         'src/cleanup_queue.cc',
         'src/connect_wrap.cc',
@@ -525,10 +526,12 @@
         'src/node_process_events.cc',
         'src/node_process_methods.cc',
         'src/node_process_object.cc',
+        'src/node_realm.cc',
         'src/node_report.cc',
         'src/node_report_module.cc',
         'src/node_report_utils.cc',
         'src/node_serdes.cc',
+        'src/node_shadow_realm.cc',
         'src/node_snapshotable.cc',
         'src/node_sockaddr.cc',
         'src/node_stat_watcher.cc',
@@ -584,6 +587,7 @@
         'src/connection_wrap.h',
         'src/debug_utils.h',
         'src/debug_utils-inl.h',
+        'src/env_properties.h',
         'src/env.h',
         'src/env-inl.h',
         'src/handle_wrap.h',
@@ -631,16 +635,20 @@
         'src/node_platform.h',
         'src/node_process.h',
         'src/node_process-inl.h',
+        'src/node_realm.h',
+        'src/node_realm-inl.h',
         'src/node_report.h',
         'src/node_revert.h',
         'src/node_root_certs.h',
+        'src/node_shadow_realm.h',
         'src/node_snapshotable.h',
         'src/node_snapshot_builder.h',
         'src/node_sockaddr.h',
         'src/node_sockaddr-inl.h',
         'src/node_stat_watcher.h',
         'src/node_union_bytes.h',
         'src/node_url.h',
+        'src/node_util.h',
         'src/node_version.h',
         'src/node_v8.h',
         'src/node_v8_platform-inl.h',

src/api/embed_helpers.cc

@@ -68,7 +68,7 @@ Maybe<int> SpinEventLoop(Environment* env) {
   env->set_snapshot_serialize_callback(Local<Function>());
 
   env->PrintInfoForSnapshotIfDebug();
-  env->VerifyNoStrongBaseObjects();
+  env->ForEachRealm([](Realm* realm) { realm->VerifyNoStrongBaseObjects(); });
   return EmitProcessExit(env);
 }
 

src/api/environment.cc

@@ -5,6 +5,8 @@
 #include "node_internals.h"
 #include "node_options-inl.h"
 #include "node_platform.h"
+#include "node_realm-inl.h"
+#include "node_shadow_realm.h"
 #include "node_v8_platform-inl.h"
 #include "node_wasm_web_api.h"
 #include "uv.h"
@@ -264,6 +266,12 @@ void SetIsolateMiscHandlers(v8::Isolate* isolate, const IsolateSettings& s) {
     isolate->SetWasmStreamingCallback(wasm_web_api::StartStreamingCompilation);
   }
 
+  if (per_process::cli_options->get_per_isolate_options()
+          ->experimental_shadow_realm) {
+    isolate->SetHostCreateShadowRealmContextCallback(
+        shadow_realm::HostCreateShadowRealmContextCallback);
+  }
+
   if ((s.flags & SHOULD_NOT_SET_PROMISE_REJECTION_CALLBACK) == 0) {
     auto* promise_reject_cb = s.promise_reject_callback ?
       s.promise_reject_callback : PromiseRejectCallback;
@@ -371,7 +379,7 @@ Environment* CreateEnvironment(
   }
 #endif
 
-  if (env->RunBootstrapping().IsEmpty()) {
+  if (env->principal_realm()->RunBootstrapping().IsEmpty()) {
     FreeEnvironment(env);
     return nullptr;
   }
@@ -446,11 +454,13 @@ MaybeLocal<Value> LoadEnvironment(
         builtins::BuiltinLoader::Add(
             name.c_str(), UnionBytes(**main_utf16, main_utf16->length()));
         env->set_main_utf16(std::move(main_utf16));
+        Realm* realm = env->principal_realm();
+
         // Arguments must match the parameters specified in
         // BuiltinLoader::LookupAndCompile().
-        std::vector<Local<Value>> args = {env->process_object(),
-                                          env->builtin_module_require()};
-        return ExecuteBootstrapper(env, name.c_str(), &args);
+        std::vector<Local<Value>> args = {realm->process_object(),
+                                          realm->builtin_module_require()};
+        return realm->ExecuteBootstrapper(name.c_str(), &args);
       });
 }
 

src/base_object-inl.h

@@ -32,6 +32,15 @@
 
 namespace node {
 
+BaseObject::BaseObject(Environment* env, v8::Local<v8::Object> object)
+    : BaseObject(env->principal_realm(), object) {}
+
+// static
+v8::Local<v8::FunctionTemplate> BaseObject::GetConstructorTemplate(
+    Environment* env) {
+  return BaseObject::GetConstructorTemplate(env->isolate_data());
+}
+
 void BaseObject::Detach() {
   CHECK_GT(pointer_data()->strong_ptr_count, 0);
   pointer_data()->is_detached = true;
@@ -57,17 +66,31 @@ v8::Local<v8::Object> BaseObject::object(v8::Isolate* isolate) const {
 }
 
 Environment* BaseObject::env() const {
-  return env_;
+  return realm_->env();
+}
+
+Realm* BaseObject::realm() const {
+  return realm_;
+}
+
+void BaseObject::TagNodeObject(v8::Local<v8::Object> object) {
+  DCHECK_GE(object->InternalFieldCount(), BaseObject::kInternalFieldCount);
+  object->SetAlignedPointerInInternalField(BaseObject::kEmbedderType,
+                                           &kNodeEmbedderId);
+}
+
+void BaseObject::SetInternalFields(v8::Local<v8::Object> object, void* slot) {
+  TagNodeObject(object);
+  object->SetAlignedPointerInInternalField(BaseObject::kSlot, slot);
 }
 
 BaseObject* BaseObject::FromJSObject(v8::Local<v8::Value> value) {
   v8::Local<v8::Object> obj = value.As<v8::Object>();
-  DCHECK_GE(obj->InternalFieldCount(), BaseObject::kSlot);
+  DCHECK_GE(obj->InternalFieldCount(), BaseObject::kInternalFieldCount);
   return static_cast<BaseObject*>(
       obj->GetAlignedPointerFromInternalField(BaseObject::kSlot));
 }
 
-
 template <typename T>
 T* BaseObject::FromJSObject(v8::Local<v8::Value> object) {
   return static_cast<T*>(FromJSObject(object));