net: make net.BlockList cloneable

Signed-off-by: James M Snell <jasnell@gmail.com>
nodejs · jasnell · Mar 25, 2021 · Mar 25, 2021 · Mar 25, 2021 · Mar 30, 2021
commit bc6cfdf4164c8f50893ff3424f5ffb1641a8bfdc
diff --git a/doc/api/worker_threads.md b/doc/api/worker_threads.md
@@ -527,6 +527,9 @@ are part of the channel.
 <!-- YAML
 added: v10.5.0
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/37917
+    description: Add 'BlockList' to the list of cloneable types.
   - version: v15.9.0
     pr-url: https://github.com/nodejs/node/pull/37155
     description: Add 'Histogram' types to the list of cloneable types.
@@ -569,6 +572,7 @@ In particular, the significant differences to `JSON` are:
   * {Histogram}s,
   * {KeyObject}s,
   * {MessagePort}s,
+  * {net.BlockList}s,
   * {X509Certificate}s.
 
 ```js

diff --git a/lib/internal/blocklist.js b/lib/internal/blocklist.js
@@ -2,6 +2,7 @@
 
 const {
   Boolean,
+  ObjectSetPrototypeOf,
   Symbol
 } = primordials;
 
@@ -14,26 +15,28 @@ const {
 const {
   customInspectSymbol: kInspect,
 } = require('internal/util');
+
+const {
+  JSTransferable,
+  kClone,
+  kDeserialize,
+} = require('internal/worker/js_transferable');
+
 const { inspect } = require('internal/util/inspect');
 
 const kHandle = Symbol('kHandle');
 const { owner_symbol } = internalBinding('symbols');
 
 const {
-  ERR_INVALID_ARG_TYPE,
   ERR_INVALID_ARG_VALUE,
 } = require('internal/errors').codes;
 
 const { validateInt32, validateString } = require('internal/validators');
 
-class BlockList {
-  constructor(handle = new BlockListHandle()) {
-    // The handle argument is an intentionally undocumented
-    // internal API. User code will not be able to create
-    // a BlockListHandle object directly.
-    if (!(handle instanceof BlockListHandle))
-      throw new ERR_INVALID_ARG_TYPE('handle', 'BlockListHandle', handle);
-    this[kHandle] = handle;
+class BlockList extends JSTransferable {
+  constructor() {
+    super();
+    this[kHandle] = new BlockListHandle();
     this[kHandle][owner_symbol] = this;
   }
 
@@ -107,6 +110,34 @@ class BlockList {
   get rules() {
     return this[kHandle].getRules();
   }
+
+  [kClone]() {
+    const handle = this[kHandle];
+    return {
+      data: { handle },
+      deserializeInfo: 'internal/blocklist:InternalBlockList',
+    };
+  }
+
+  [kDeserialize]({ handle }) {
+    this[kHandle] = handle;
+    this[kHandle][owner_symbol] = this;
+  }
+}
+
+class InternalBlockList extends JSTransferable {
+  constructor(handle) {
+    super();
+    this[kHandle] = handle;
+    if (handle !== undefined)
+      handle[owner_symbol] = this;
+  }
 }
 
-module.exports = BlockList;
+InternalBlockList.prototype.constructor = BlockList.prototype.constructor;
+ObjectSetPrototypeOf(InternalBlockList.prototype, BlockList.prototype);
+
+module.exports = {
+  BlockList,
+  InternalBlockList,
+};
diff --git a/lib/net.js b/lib/net.js
@@ -1760,8 +1760,7 @@ module.exports = {
   _normalizeArgs: normalizeArgs,
   _setSimultaneousAccepts,
   get BlockList() {
-    if (BlockList === undefined)
-      BlockList = require('internal/blocklist');
+    BlockList ??= require('internal/blocklist').BlockList;
     return BlockList;
   },
   connect,

diff --git a/src/env-inl.h b/src/env-inl.h
@@ -1026,15 +1026,18 @@ inline void Environment::SetInstanceMethod(v8::Local<v8::FunctionTemplate> that,
 inline void Environment::SetConstructorFunction(
     v8::Local<v8::Object> that,
     const char* name,
-    v8::Local<v8::FunctionTemplate> tmpl) {
-  SetConstructorFunction(that, OneByteString(isolate(), name), tmpl);
+    v8::Local<v8::FunctionTemplate> tmpl,
+    SetConstructorFunctionFlag flag) {
+  SetConstructorFunction(that, OneByteString(isolate(), name), tmpl, flag);
 }
 
 inline void Environment::SetConstructorFunction(
     v8::Local<v8::Object> that,
     v8::Local<v8::String> name,
-    v8::Local<v8::FunctionTemplate> tmpl) {
-  tmpl->SetClassName(name);
+    v8::Local<v8::FunctionTemplate> tmpl,
+    SetConstructorFunctionFlag flag) {
+  if (LIKELY(flag == SetConstructorFunctionFlag::SET_CLASS_NAME))
+    tmpl->SetClassName(name);
   that->Set(
       context(),
       name,

diff --git a/src/env.h b/src/env.h
@@ -452,7 +452,7 @@ constexpr size_t kFsStatsBufferLength =
   V(base_object_ctor_template, v8::FunctionTemplate)                           \
   V(binding_data_ctor_template, v8::FunctionTemplate)                          \
   V(blob_constructor_template, v8::FunctionTemplate)                           \
-  V(blocklist_instance_template, v8::ObjectTemplate)                           \
+  V(blocklist_constructor_template, v8::FunctionTemplate)                      \
   V(compiled_fn_entry_template, v8::ObjectTemplate)                            \
   V(dir_instance_template, v8::ObjectTemplate)                                 \
   V(fd_constructor_template, v8::ObjectTemplate)                               \
@@ -1237,13 +1237,22 @@ class Environment : public MemoryRetainer {
                                          const char* name,
                                          v8::FunctionCallback callback);
 
+  enum class SetConstructorFunctionFlag {
+    NONE,
+    SET_CLASS_NAME,
+  };
+
   inline void SetConstructorFunction(v8::Local<v8::Object> that,
                           const char* name,
-                          v8::Local<v8::FunctionTemplate> tmpl);
+                          v8::Local<v8::FunctionTemplate> tmpl,
+                          SetConstructorFunctionFlag flag =
+                              SetConstructorFunctionFlag::SET_CLASS_NAME);
 
   inline void SetConstructorFunction(v8::Local<v8::Object> that,
                           v8::Local<v8::String> name,
-                          v8::Local<v8::FunctionTemplate> tmpl);
+                          v8::Local<v8::FunctionTemplate> tmpl,
+                          SetConstructorFunctionFlag flag =
+                              SetConstructorFunctionFlag::SET_CLASS_NAME);
 
   void AtExit(void (*cb)(void* arg), void* arg);
   void RunAtExitCallbacks();