n-api: add napi_fatal_exception

Add function to trigger and uncaught exception. Useful if an async callback throws an exception with no way to recover. Backport-PR-URL: #19265 PR-URL: #19337 Reviewed-By: James M Snell <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Michael Dawson <[email protected]>

Author: mafintosh

doc/api/n-api.md

@@ -541,6 +541,20 @@ This API returns true if an exception is pending.
 
 This API can be called even if there is a pending JavaScript exception.
 
+#### napi_fatal_exception
+<!-- YAML
+added: REPLACEME
+-->
+```C
+napi_status napi_fatal_exception(napi_env env, napi_value err);
+```
+
+- `[in] env`: The environment that the API is invoked under.
+- `[in] err`: The error you want to pass to `uncaughtException`.
+
+Trigger an `uncaughtException` in JavaScript. Useful if an async
+callback throws an exception with no way to recover.
+
 ### Fatal Errors
 
 In the event of an unrecoverable error in a native module, a fatal error can be

src/node_api.cc

@@ -173,6 +173,7 @@ struct napi_env__{
  (out) = v8::type::New((buffer), (byte_offset), (length)); \
  } while (0)
 
+
 namespace{
 namespacev8impl{
 
@@ -295,6 +296,13 @@ v8::Local<v8::Value> V8LocalValueFromJsValue(napi_value v){
 return local;
 }
 
+staticinlinevoidtrigger_fatal_exception(
+ napi_env env, v8::Local<v8::Value> local_err){
+ v8::Local<v8::Message> local_msg =
+v8::Exception::CreateMessage(env->isolate, local_err);
+node::FatalException(env->isolate, local_err, local_msg);
+}
+
 staticinline napi_status V8NameFromPropertyDescriptor(napi_env env,
 const napi_property_descriptor* p,
  v8::Local<v8::Name>* result){
@@ -971,6 +979,16 @@ napi_status napi_get_last_error_info(napi_env env,
 return napi_ok;
 }
 
+napi_status napi_fatal_exception(napi_env env, napi_value err){
+NAPI_PREAMBLE(env);
+CHECK_ARG(env, err);
+
+ v8::Local<v8::Value> local_err = v8impl::V8LocalValueFromJsValue(err);
+v8impl::trigger_fatal_exception(env, local_err);
+
+returnnapi_clear_last_error(env);
+}
+
 NAPI_NO_RETURN voidnapi_fatal_error(constchar* location,
 size_t location_len,
 constchar* message,
@@ -3375,10 +3393,9 @@ class Work : public node::AsyncResource{
 // report it as a fatal exception. (There is no JavaScript on the
 // callstack that can possibly handle it.)
 if (!env->last_exception.IsEmpty()){
- v8::TryCatch try_catch(env->isolate);
- env->isolate->ThrowException(
- v8::Local<v8::Value>::New(env->isolate, env->last_exception));
-node::FatalException(env->isolate, try_catch);
+ v8::Local<v8::Value> local_err = v8::Local<v8::Value>::New(
+ env->isolate, env->last_exception);
+v8impl::trigger_fatal_exception(env, local_err);
  }
  }
  }

src/node_api.h

@@ -112,6 +112,8 @@ NAPI_EXTERN napi_status
 napi_get_last_error_info(napi_envenv,
 constnapi_extended_error_info**result);
 
+NAPI_EXTERNnapi_statusnapi_fatal_exception(napi_envenv, napi_valueerr);
+
 NAPI_EXTERNNAPI_NO_RETURNvoidnapi_fatal_error(constchar*location,
 size_tlocation_len,
 constchar*message,

src/node_internals.h

@@ -218,6 +218,11 @@ void GetSockOrPeerName(const v8::FunctionCallbackInfo<v8::Value>& args){
  args.GetReturnValue().Set(err);
 }
 
+voidFatalException(v8::Isolate* isolate,
+ v8::Local<v8::Value> error,
+ v8::Local<v8::Message> message);
+
+
 voidSignalExit(int signo);
 #ifdef __POSIX__
 voidRegisterSignalHandler(int signal,

test/addons-napi/test_async/test-uncaught.js

@@ -0,0 +1,18 @@
+'use strict';
+constcommon=require('../../common');
+constassert=require('assert');
+consttest_async=require(`./build/${common.buildType}/test_async`);
+
+process.on('uncaughtException',common.mustCall(function(err){
+try{
+thrownewError('should not fail');
+}catch(err){
+assert.strictEqual(err.message,'should not fail');
+}
+assert.strictEqual(err.message,'uncaught');
+}));
+
+// Successful async execution and completion callback.
+test_async.Test(5,{},common.mustCall(function(){
+thrownewError('uncaught');
+}));

test/addons-napi/test_fatal_exception/binding.gyp

@@ -0,0 +1,8 @@
+{
+"targets": [
+{
+"target_name": "test_fatal_exception",
+"sources": [ "test_fatal_exception.c" ]
+ }
+ ]
+}

test/addons-napi/test_fatal_exception/test.js

@@ -0,0 +1,11 @@
+'use strict';
+constcommon=require('../../common');
+constassert=require('assert');
+consttest_fatal=require(`./build/${common.buildType}/test_fatal_exception`);
+
+process.on('uncaughtException',common.mustCall(function(err){
+assert.strictEqual(err.message,'fatal error');
+}));
+
+consterr=newError('fatal error');
+test_fatal.Test(err);

test/addons-napi/test_fatal_exception/test_fatal_exception.c

@@ -0,0 +1,26 @@
+#include<node_api.h>
+#include"../common.h"
+
+napi_valueTest(napi_envenv, napi_callback_infoinfo){
+napi_valueerr;
+size_targc=1;
+
+NAPI_CALL(env, napi_get_cb_info(env, info, &argc, &err, NULL, NULL));
+
+NAPI_CALL(env, napi_fatal_exception(env, err));
+
+returnNULL;
+}
+
+napi_valueInit(napi_envenv, napi_valueexports){
+napi_property_descriptorproperties[] ={
+DECLARE_NAPI_PROPERTY("Test", Test),
+ };
+
+NAPI_CALL(env, napi_define_properties(
+env, exports, sizeof(properties) / sizeof(*properties), properties));
+
+returnexports;
+}
+
+NAPI_MODULE(NODE_GYP_MODULE_NAME, Init)