src: allow embedder control of code generation policy

Author: codebytere

src/api/environment.cc

@@ -265,8 +265,13 @@ void SetIsolateMiscHandlers(v8::Isolate* isolate, const IsolateSettings& s) {
   auto* allow_wasm_codegen_cb = s.allow_wasm_code_generation_callback ?
     s.allow_wasm_code_generation_callback : AllowWasmCodeGenerationCallback;
   isolate->SetAllowWasmCodeGenerationCallback(allow_wasm_codegen_cb);
-  isolate->SetModifyCodeGenerationFromStringsCallback(
-      ModifyCodeGenerationFromStrings);
+
+  auto* modify_code_generation_from_strings_callback = ModifyCodeGenerationFromStrings;
+  if (s.flags & ALLOW_MODIFY_CODE_GENERATION_FROM_STRINGS_CALLBACK 
+    && s.modify_code_generation_from_strings_callback) {
+    modify_code_generation_from_strings_callback = s.modify_code_generation_from_strings_callback;
+  }
+  isolate->SetModifyCodeGenerationFromStringsCallback(modify_code_generation_from_strings_callback);
 
   Mutex::ScopedLock lock(node::per_process::cli_options_mutex);
   if (per_process::cli_options->get_per_isolate_options()

src/node.h

@@ -453,7 +453,8 @@ enum IsolateSettingsFlags {
   MESSAGE_LISTENER_WITH_ERROR_LEVEL = 1 << 0,
   DETAILED_SOURCE_POSITIONS_FOR_PROFILING = 1 << 1,
   SHOULD_NOT_SET_PROMISE_REJECTION_CALLBACK = 1 << 2,
-  SHOULD_NOT_SET_PREPARE_STACK_TRACE_CALLBACK = 1 << 3
+  SHOULD_NOT_SET_PREPARE_STACK_TRACE_CALLBACK = 1 << 3,
+  ALLOW_MODIFY_CODE_GENERATION_FROM_STRINGS_CALLBACK = 1 << 4,
 };
 
 struct IsolateSettings {
@@ -471,6 +472,8 @@ struct IsolateSettings {
   v8::PromiseRejectCallback promise_reject_callback = nullptr;
   v8::AllowWasmCodeGenerationCallback
       allow_wasm_code_generation_callback = nullptr;
+  v8::ModifyCodeGenerationFromStringsCallback2
+      modify_code_generation_from_strings_callback = nullptr;
 };
 
 // Overriding IsolateSettings may produce unexpected behavior