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#include "env-inl.h"
#include "node.h"
#include "node_errors.h"
#include "node_internals.h"
#include "node_process.h"
#include "util-inl.h"
#include "v8.h"
#include <atomic>
namespace node {
using errors::TryCatchScope;
using v8::Context;
using v8::Function;
using v8::FunctionCallbackInfo;
using v8::Isolate;
using v8::kPromiseHandlerAddedAfterReject;
using v8::kPromiseRejectAfterResolved;
using v8::kPromiseRejectWithNoHandler;
using v8::kPromiseResolveAfterResolved;
using v8::Local;
using v8::MicrotasksScope;
using v8::Number;
using v8::Object;
using v8::Promise;
using v8::PromiseRejectEvent;
using v8::PromiseRejectMessage;
using v8::Value;
namespace task_queue {
static void EnqueueMicrotask(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
Isolate* isolate = env->isolate();
CHECK(args[0]->IsFunction());
isolate->EnqueueMicrotask(args[0].As<Function>());
}
static void RunMicrotasks(const FunctionCallbackInfo<Value>& args) {
MicrotasksScope::PerformCheckpoint(args.GetIsolate());
}
static void SetTickCallback(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args[0]->IsFunction());
env->set_tick_callback_function(args[0].As<Function>());
}
void PromiseRejectCallback(PromiseRejectMessage message) {
static std::atomic<uint64_t> unhandledRejections{0};
static std::atomic<uint64_t> rejectionsHandledAfter{0};
Local<Promise> promise = message.GetPromise();
Isolate* isolate = promise->GetIsolate();
PromiseRejectEvent event = message.GetEvent();
Environment* env = Environment::GetCurrent(isolate);
if (env == nullptr) return;
Local<Function> callback = env->promise_reject_callback();
// The promise is rejected before JS land calls SetPromiseRejectCallback
// to initializes the promise reject callback during bootstrap.
CHECK(!callback.IsEmpty());
Local<Value> value;
Local<Value> type = Number::New(env->isolate(), event);
if (event == kPromiseRejectWithNoHandler) {
value = message.GetValue();
unhandledRejections++;
TRACE_COUNTER2(TRACING_CATEGORY_NODE2(promises, rejections),
"rejections",
"unhandled", unhandledRejections,
"handledAfter", rejectionsHandledAfter);
} else if (event == kPromiseHandlerAddedAfterReject) {
value = Undefined(isolate);
rejectionsHandledAfter++;
TRACE_COUNTER2(TRACING_CATEGORY_NODE2(promises, rejections),
"rejections",
"unhandled", unhandledRejections,
"handledAfter", rejectionsHandledAfter);
} else if (event == kPromiseResolveAfterResolved) {
value = message.GetValue();
} else if (event == kPromiseRejectAfterResolved) {
value = message.GetValue();
} else {
return;
}
if (value.IsEmpty()) {
value = Undefined(isolate);
}
Local<Value> args[] = { type, promise, value };
// V8 does not expect this callback to have a scheduled exceptions once it
// returns, so we print them out in a best effort to do something about it
// without failing silently and without crashing the process.
TryCatchScope try_catch(env);
USE(callback->Call(
env->context(), Undefined(isolate), arraysize(args), args));
if (try_catch.HasCaught() && !try_catch.HasTerminated()) {
fprintf(stderr, "Exception in PromiseRejectCallback:\n");
PrintCaughtException(isolate, env->context(), try_catch);
}
}
static void SetPromiseRejectCallback(
const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args[0]->IsFunction());
env->set_promise_reject_callback(args[0].As<Function>());
}
static void Initialize(Local<Object> target,
Local<Value> unused,
Local<Context> context,
void* priv) {
Environment* env = Environment::GetCurrent(context);
Isolate* isolate = env->isolate();
env->SetMethod(target, "enqueueMicrotask", EnqueueMicrotask);
env->SetMethod(target, "setTickCallback", SetTickCallback);
env->SetMethod(target, "runMicrotasks", RunMicrotasks);
target->Set(env->context(),
FIXED_ONE_BYTE_STRING(isolate, "tickInfo"),
env->tick_info()->fields().GetJSArray()).Check();
Local<Object> events = Object::New(isolate);
NODE_DEFINE_CONSTANT(events, kPromiseRejectWithNoHandler);
NODE_DEFINE_CONSTANT(events, kPromiseHandlerAddedAfterReject);
NODE_DEFINE_CONSTANT(events, kPromiseResolveAfterResolved);
NODE_DEFINE_CONSTANT(events, kPromiseRejectAfterResolved);
target->Set(env->context(),
FIXED_ONE_BYTE_STRING(isolate, "promiseRejectEvents"),
events).Check();
env->SetMethod(target,
"setPromiseRejectCallback",
SetPromiseRejectCallback);
}
} // namespace task_queue
} // namespace node
NODE_MODULE_CONTEXT_AWARE_INTERNAL(task_queue, node::task_queue::Initialize)
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