#include "env.h"

#include "async_wrap.h"

#include "memory_tracker-inl.h"

#include "node_buffer.h"

#include "node_context_data.h"

#include "node_errors.h"

#include "node_file.h"

#include "node_internals.h"

#include "node_native_module.h"

#include "node_options-inl.h"

#include "node_process.h"

#include "node_v8_platform-inl.h"

#include "node_worker.h"

#include "tracing/agent.h"

#include "tracing/traced_value.h"

#include "util-inl.h"

#include "v8-profiler.h"

#include <algorithm>

#include <atomic>

#include <cstdio>

#include <memory>

namespace node {

using errors::TryCatchScope;

using v8::ArrayBuffer;

using v8::Boolean;

using v8::Context;

using v8::EmbedderGraph;

using v8::Function;

using v8::FunctionTemplate;

using v8::HandleScope;

using v8::Integer;

using v8::Isolate;

using v8::Local;

using v8::NewStringType;

using v8::Number;

using v8::Object;

using v8::Private;

using v8::SnapshotCreator;

using v8::StackTrace;

using v8::String;

using v8::Symbol;

using v8::TracingController;

using v8::Undefined;

using v8::Value;

using worker::Worker;

int const Environment::kNodeContextTag = 0x6e6f64;

void* const Environment::kNodeContextTagPtr = const_cast<void*>(

static_cast<const void*>(&Environment::kNodeContextTag));

std::vector<size_t> IsolateData::Serialize(SnapshotCreator* creator) {

Isolate* isolate = creator->GetIsolate();

std::vector<size_t> indexes;

HandleScope handle_scope(isolate);

// XXX(joyeecheung): technically speaking, the indexes here should be

// consecutive and we could just return a range instead of an array,

// but that's not part of the V8 API contract so we use an array

// just to be safe.

#define VP(PropertyName, StringValue) V(v8::Private, PropertyName)

#define VY(PropertyName, StringValue) V(v8::Symbol, PropertyName)

#define VS(PropertyName, StringValue) V(v8::String, PropertyName)

#define V(TypeName, PropertyName) \

indexes.push_back(creator->AddData(PropertyName##_.Get(isolate)));

PER_ISOLATE_PRIVATE_SYMBOL_PROPERTIES(VP)

PER_ISOLATE_SYMBOL_PROPERTIES(VY)

PER_ISOLATE_STRING_PROPERTIES(VS)

#undef V

#undef VY

#undef VS

#undef VP

return indexes;

}

void IsolateData::DeserializeProperties(const std::vector<size_t>* indexes) {

size_t i = 0;

HandleScope handle_scope(isolate_);

#define VP(PropertyName, StringValue) V(v8::Private, PropertyName)

#define VY(PropertyName, StringValue) V(v8::Symbol, PropertyName)

#define VS(PropertyName, StringValue) V(v8::String, PropertyName)

#define V(TypeName, PropertyName) \

do { \

MaybeLocal<TypeName> field = \

isolate_->GetDataFromSnapshotOnce<TypeName>((*indexes)[i++]); \

if (field.IsEmpty()) { \

fprintf(stderr, "Failed to deserialize " #PropertyName "\n"); \

} \

PropertyName##_.Set(isolate_, field.ToLocalChecked()); \

} while (0);

PER_ISOLATE_PRIVATE_SYMBOL_PROPERTIES(VP)

PER_ISOLATE_SYMBOL_PROPERTIES(VY)

PER_ISOLATE_STRING_PROPERTIES(VS)

#undef V

#undef VY

#undef VS

#undef VP

}

void IsolateData::CreateProperties() {

// Create string and private symbol properties as internalized one byte

// strings after the platform is properly initialized.

//

// Internalized because it makes property lookups a little faster and

// because the string is created in the old space straight away. It's going

// to end up in the old space sooner or later anyway but now it doesn't go

// through v8::Eternal's new space handling first.

//

// One byte because our strings are ASCII and we can safely skip V8's UTF-8

// decoding step.

HandleScope handle_scope(isolate_);

#define V(PropertyName, StringValue) \

PropertyName##_.Set( \

isolate_, \

Private::New(isolate_, \

String::NewFromOneByte( \

isolate_, \

reinterpret_cast<const uint8_t*>(StringValue), \

NewStringType::kInternalized, \

sizeof(StringValue) - 1) \

.ToLocalChecked()));

PER_ISOLATE_PRIVATE_SYMBOL_PROPERTIES(V)

#undef V

#define V(PropertyName, StringValue) \

PropertyName##_.Set( \

isolate_, \

Symbol::New(isolate_, \

String::NewFromOneByte( \

isolate_, \

reinterpret_cast<const uint8_t*>(StringValue), \

NewStringType::kInternalized, \

sizeof(StringValue) - 1) \

.ToLocalChecked()));

PER_ISOLATE_SYMBOL_PROPERTIES(V)

#undef V

#define V(PropertyName, StringValue) \

PropertyName##_.Set( \

isolate_, \

String::NewFromOneByte(isolate_, \

reinterpret_cast<const uint8_t*>(StringValue), \

NewStringType::kInternalized, \

sizeof(StringValue) - 1) \

.ToLocalChecked());

PER_ISOLATE_STRING_PROPERTIES(V)

#undef V

}

IsolateData::IsolateData(Isolate* isolate,

uv_loop_t* event_loop,

MultiIsolatePlatform* platform,

ArrayBufferAllocator* node_allocator,

const std::vector<size_t>* indexes)

: isolate_(isolate),

event_loop_(event_loop),

allocator_(isolate->GetArrayBufferAllocator()),

node_allocator_(node_allocator == nullptr ? nullptr

: node_allocator->GetImpl()),

uses_node_allocator_(allocator_ == node_allocator_),

platform_(platform) {

CHECK_NOT_NULL(allocator_);

options_.reset(

new PerIsolateOptions(*(per_process::cli_options->per_isolate)));

if (indexes == nullptr) {

CreateProperties();

} else {

DeserializeProperties(indexes);

}

}

void IsolateData::MemoryInfo(MemoryTracker* tracker) const {

#define V(PropertyName, StringValue) \

tracker->TrackField(#PropertyName, PropertyName(isolate()));

PER_ISOLATE_SYMBOL_PROPERTIES(V)

#undef V

#define V(PropertyName, StringValue) \

tracker->TrackField(#PropertyName, PropertyName(isolate()));

PER_ISOLATE_STRING_PROPERTIES(V)

#undef V

if (node_allocator_ != nullptr) {

tracker->TrackFieldWithSize(

"node_allocator", sizeof(*node_allocator_), "NodeArrayBufferAllocator");

} else {

tracker->TrackFieldWithSize(

"allocator", sizeof(*allocator_), "v8::ArrayBuffer::Allocator");

}

tracker->TrackFieldWithSize(

"platform", sizeof(*platform_), "MultiIsolatePlatform");

// TODO(joyeecheung): implement MemoryRetainer in the option classes.

}

void InitThreadLocalOnce() {

CHECK_EQ(0, uv_key_create(&Environment::thread_local_env));

}

void TrackingTraceStateObserver::UpdateTraceCategoryState() {

if (!env_->owns_process_state()) {

// Ideally, we’d have a consistent story that treats all threads/Environment

// instances equally here. However, tracing is essentially global, and this

// callback is called from whichever thread calls `StartTracing()` or

// `StopTracing()`. The only way to do this in a threadsafe fashion

// seems to be only tracking this from the main thread, and only allowing

// these state modifications from the main thread.

return;

}

bool async_hooks_enabled = (*(TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(

TRACING_CATEGORY_NODE1(async_hooks)))) != 0;

Isolate* isolate = env_->isolate();

HandleScope handle_scope(isolate);

Local<Function> cb = env_->trace_category_state_function();

if (cb.IsEmpty())

return;

TryCatchScope try_catch(env_);

try_catch.SetVerbose(true);

Local<Value> args[] = {Boolean::New(isolate, async_hooks_enabled)};

cb->Call(env_->context(), Undefined(isolate), arraysize(args), args)

.ToLocalChecked();

}

static std::atomic<uint64_t> next_thread_id{0};

uint64_t Environment::AllocateThreadId() {

return next_thread_id++;

}

void Environment::CreateProperties() {

HandleScope handle_scope(isolate_);

Local<Context> ctx = context();

Local<FunctionTemplate> templ = FunctionTemplate::New(isolate());

templ->InstanceTemplate()->SetInternalFieldCount(1);

Local<Object> obj = templ->GetFunction(ctx)

.ToLocalChecked()

->NewInstance(ctx)

.ToLocalChecked();

obj->SetAlignedPointerInInternalField(0, this);

set_as_callback_data(obj);

set_as_callback_data_template(templ);

// Store primordials setup by the per-context script in the environment.

Local<Object> per_context_bindings =

GetPerContextExports(ctx).ToLocalChecked();

Local<Value> primordials =

per_context_bindings->Get(ctx, primordials_string()).ToLocalChecked();

CHECK(primordials->IsObject());

set_primordials(primordials.As<Object>());

Local<Object> process_object =

node::CreateProcessObject(this).FromMaybe(Local<Object>());

set_process_object(process_object);

}

Environment::Environment(IsolateData* isolate_data,

Local<Context> context,

const std::vector<std::string>& args,

const std::vector<std::string>& exec_args,

Flags flags,

uint64_t thread_id)

: isolate_(context->GetIsolate()),

isolate_data_(isolate_data),

immediate_info_(context->GetIsolate()),

tick_info_(context->GetIsolate()),

timer_base_(uv_now(isolate_data->event_loop())),

exec_argv_(exec_args),

argv_(args),

should_abort_on_uncaught_toggle_(isolate_, 1),

stream_base_state_(isolate_, StreamBase::kNumStreamBaseStateFields),

flags_(flags),

thread_id_(thread_id == kNoThreadId ? AllocateThreadId() : thread_id),

fs_stats_field_array_(isolate_, kFsStatsBufferLength),

fs_stats_field_bigint_array_(isolate_, kFsStatsBufferLength),

context_(context->GetIsolate(), context) {

// We'll be creating new objects so make sure we've entered the context.

HandleScope handle_scope(isolate());

Context::Scope context_scope(context);

set_env_vars(per_process::system_environment);

// We create new copies of the per-Environment option sets, so that it is

// easier to modify them after Environment creation. The defaults are

// part of the per-Isolate option set, for which in turn the defaults are

// part of the per-process option set.

options_.reset(new EnvironmentOptions(*isolate_data->options()->per_env));

inspector_host_port_.reset(new HostPort(options_->debug_options().host_port));

#if HAVE_INSPECTOR

// We can only create the inspector agent after having cloned the options.

inspector_agent_ = std::make_unique<inspector::Agent>(this);

#endif

AssignToContext(context, ContextInfo(""));

if (tracing::AgentWriterHandle* writer = GetTracingAgentWriter()) {

trace_state_observer_ = std::make_unique<TrackingTraceStateObserver>(this);

TracingController* tracing_controller = writer->GetTracingController();

tracing_controller->AddTraceStateObserver(trace_state_observer_.get());

}

destroy_async_id_list_.reserve(512);

BeforeExit(

[](void* arg) {

Environment* env = static_cast<Environment*>(arg);

if (!env->destroy_async_id_list()->empty())

AsyncWrap::DestroyAsyncIdsCallback(env, nullptr);

},

this);

performance_state_ =

std::make_unique<performance::performance_state>(isolate());

performance_state_->Mark(

performance::NODE_PERFORMANCE_MILESTONE_ENVIRONMENT);

performance_state_->Mark(performance::NODE_PERFORMANCE_MILESTONE_NODE_START,

per_process::node_start_time);

performance_state_->Mark(

performance::NODE_PERFORMANCE_MILESTONE_V8_START,

performance::performance_v8_start);

if (*TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(

TRACING_CATEGORY_NODE1(environment)) != 0) {

auto traced_value = tracing::TracedValue::Create();

traced_value->BeginArray("args");

for (const std::string& arg : args) traced_value->AppendString(arg);

traced_value->EndArray();

traced_value->BeginArray("exec_args");

for (const std::string& arg : exec_args) traced_value->AppendString(arg);

traced_value->EndArray();

TRACE_EVENT_NESTABLE_ASYNC_BEGIN1(TRACING_CATEGORY_NODE1(environment),

"Environment",

this,

"args",

std::move(traced_value));

}

// By default, always abort when --abort-on-uncaught-exception was passed.

should_abort_on_uncaught_toggle_[0] = 1;

std::string debug_cats;

credentials::SafeGetenv("NODE_DEBUG_NATIVE", &debug_cats, this);

set_debug_categories(debug_cats, true);

if (options_->no_force_async_hooks_checks) {

async_hooks_.no_force_checks();

}

// TODO(joyeecheung): deserialize when the snapshot covers the environment

// properties.

CreateProperties();

}

CompileFnEntry::CompileFnEntry(Environment* env, uint32_t id)

: env(env), id(id) {

env->compile_fn_entries.insert(this);

}

Environment::~Environment() {

isolate()->GetHeapProfiler()->RemoveBuildEmbedderGraphCallback(

BuildEmbedderGraph, this);

// Make sure there are no re-used libuv wrapper objects.

// CleanupHandles() should have removed all of them.

CHECK(file_handle_read_wrap_freelist_.empty());

// dispose the Persistent references to the compileFunction

// wrappers used in the dynamic import callback

for (auto& entry : compile_fn_entries) {

delete entry;

}

HandleScope handle_scope(isolate());

#if HAVE_INSPECTOR

// Destroy inspector agent before erasing the context. The inspector

// destructor depends on the context still being accessible.

inspector_agent_.reset();

#endif

context()->SetAlignedPointerInEmbedderData(

ContextEmbedderIndex::kEnvironment, nullptr);

if (trace_state_observer_) {

tracing::AgentWriterHandle* writer = GetTracingAgentWriter();

CHECK_NOT_NULL(writer);

TracingController* tracing_controller = writer->GetTracingController();

tracing_controller->RemoveTraceStateObserver(trace_state_observer_.get());

}

delete[] heap_statistics_buffer_;

delete[] heap_space_statistics_buffer_;

delete[] http_parser_buffer_;

TRACE_EVENT_NESTABLE_ASYNC_END0(

TRACING_CATEGORY_NODE1(environment), "Environment", this);

// Do not unload addons on the main thread. Some addons need to retain memory

// beyond the Environment's lifetime, and unloading them early would break

// them; with Worker threads, we have the opportunity to be stricter.

// Also, since the main thread usually stops just before the process exits,

// this is far less relevant here.

if (!is_main_thread()) {

// Dereference all addons that were loaded into this environment.

for (binding::DLib& addon : loaded_addons_) {

addon.Close();

}

}

}

void Environment::InitializeLibuv(bool start_profiler_idle_notifier) {

HandleScope handle_scope(isolate());

Context::Scope context_scope(context());

CHECK_EQ(0, uv_timer_init(event_loop(), timer_handle()));

uv_unref(reinterpret_cast<uv_handle_t*>(timer_handle()));

uv_check_init(event_loop(), immediate_check_handle());

uv_unref(reinterpret_cast<uv_handle_t*>(immediate_check_handle()));

uv_idle_init(event_loop(), immediate_idle_handle());

uv_check_start(immediate_check_handle(), CheckImmediate);

// Inform V8's CPU profiler when we're idle. The profiler is sampling-based

// but not all samples are created equal; mark the wall clock time spent in

// epoll_wait() and friends so profiling tools can filter it out. The samples

// still end up in v8.log but with state=IDLE rather than state=EXTERNAL.

// TODO(bnoordhuis) Depends on a libuv implementation detail that we should

// probably fortify in the API contract, namely that the last started prepare

// or check watcher runs first. It's not 100% foolproof; if an add-on starts

// a prepare or check watcher after us, any samples attributed to its callback

// will be recorded with state=IDLE.

uv_prepare_init(event_loop(), &idle_prepare_handle_);

uv_check_init(event_loop(), &idle_check_handle_);

uv_unref(reinterpret_cast<uv_handle_t*>(&idle_prepare_handle_));

uv_unref(reinterpret_cast<uv_handle_t*>(&idle_check_handle_));

thread_stopper()->Install(

this, static_cast<void*>(this), [](uv_async_t* handle) {

Environment* env = static_cast<Environment*>(handle->data);

uv_stop(env->event_loop());

});

thread_stopper()->set_stopped(false);

uv_unref(reinterpret_cast<uv_handle_t*>(thread_stopper()->GetHandle()));

// Register clean-up cb to be called to clean up the handles

// when the environment is freed, note that they are not cleaned in

// the one environment per process setup, but will be called in

// FreeEnvironment.

RegisterHandleCleanups();

if (start_profiler_idle_notifier) {

StartProfilerIdleNotifier();

}

static uv_once_t init_once = UV_ONCE_INIT;

uv_once(&init_once, InitThreadLocalOnce);

uv_key_set(&thread_local_env, this);

}

void Environment::ExitEnv() {

set_can_call_into_js(false);

thread_stopper()->Stop();

isolate_->TerminateExecution();

}

void Environment::RegisterHandleCleanups() {

HandleCleanupCb close_and_finish = [](Environment* env, uv_handle_t* handle,

void* arg) {

handle->data = env;

env->CloseHandle(handle, [](uv_handle_t* handle) {

#ifdef DEBUG

memset(handle, 0xab, uv_handle_size(handle->type));

#endif

});

};

RegisterHandleCleanup(

reinterpret_cast<uv_handle_t*>(timer_handle()),

close_and_finish,

nullptr);

RegisterHandleCleanup(

reinterpret_cast<uv_handle_t*>(immediate_check_handle()),

close_and_finish,

nullptr);

RegisterHandleCleanup(

reinterpret_cast<uv_handle_t*>(immediate_idle_handle()),

close_and_finish,

nullptr);

RegisterHandleCleanup(

reinterpret_cast<uv_handle_t*>(&idle_prepare_handle_),

close_and_finish,

nullptr);

RegisterHandleCleanup(

reinterpret_cast<uv_handle_t*>(&idle_check_handle_),

close_and_finish,

nullptr);

}

void Environment::CleanupHandles() {

for (ReqWrapBase* request : req_wrap_queue_)

request->Cancel();

for (HandleWrap* handle : handle_wrap_queue_)

handle->Close();

for (HandleCleanup& hc : handle_cleanup_queue_)

hc.cb_(this, hc.handle_, hc.arg_);

handle_cleanup_queue_.clear();

while (handle_cleanup_waiting_ != 0 ||

request_waiting_ != 0 ||

!handle_wrap_queue_.IsEmpty()) {

uv_run(event_loop(), UV_RUN_ONCE);

}

file_handle_read_wrap_freelist_.clear();

}

void Environment::StartProfilerIdleNotifier() {

if (profiler_idle_notifier_started_)

return;

profiler_idle_notifier_started_ = true;

uv_prepare_start(&idle_prepare_handle_, [](uv_prepare_t* handle) {

Environment* env = ContainerOf(&Environment::idle_prepare_handle_, handle);

env->isolate()->SetIdle(true);

});

uv_check_start(&idle_check_handle_, [](uv_check_t* handle) {

Environment* env = ContainerOf(&Environment::idle_check_handle_, handle);

env->isolate()->SetIdle(false);

});

}

void Environment::StopProfilerIdleNotifier() {

profiler_idle_notifier_started_ = false;

uv_prepare_stop(&idle_prepare_handle_);

uv_check_stop(&idle_check_handle_);

}

void Environment::PrintSyncTrace() const {

if (!options_->trace_sync_io) return;

HandleScope handle_scope(isolate());

fprintf(

stderr, "(node:%d) WARNING: Detected use of sync API\n", uv_os_getpid());

PrintStackTrace(

isolate(),

StackTrace::CurrentStackTrace(isolate(), 10, StackTrace::kDetailed));

}

void Environment::RunCleanup() {

started_cleanup_ = true;

TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),

"RunCleanup", this);

thread_stopper()->Uninstall();

CleanupHandles();

while (!cleanup_hooks_.empty()) {

// Copy into a vector, since we can't sort an unordered_set in-place.

std::vector<CleanupHookCallback> callbacks(

cleanup_hooks_.begin(), cleanup_hooks_.end());

// We can't erase the copied elements from `cleanup_hooks_` yet, because we

// need to be able to check whether they were un-scheduled by another hook.

std::sort(callbacks.begin(), callbacks.end(),

[](const CleanupHookCallback& a, const CleanupHookCallback& b) {

// Sort in descending order so that the most recently inserted callbacks

// are run first.

return a.insertion_order_counter_ > b.insertion_order_counter_;

});

for (const CleanupHookCallback& cb : callbacks) {

if (cleanup_hooks_.count(cb) == 0) {

// This hook was removed from the `cleanup_hooks_` set during another

// hook that was run earlier. Nothing to do here.

continue;

}

cb.fn_(cb.arg_);

cleanup_hooks_.erase(cb);

}

CleanupHandles();

}

}

void Environment::RunBeforeExitCallbacks() {

TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),

"BeforeExit", this);

for (ExitCallback before_exit : before_exit_functions_) {

before_exit.cb_(before_exit.arg_);

}

before_exit_functions_.clear();

}

void Environment::BeforeExit(void (*cb)(void* arg), void* arg) {

before_exit_functions_.push_back(ExitCallback{cb, arg});

}

void Environment::RunAtExitCallbacks() {

TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),

"AtExit", this);

for (ExitCallback at_exit : at_exit_functions_) {

at_exit.cb_(at_exit.arg_);

}

at_exit_functions_.clear();

}

void Environment::AtExit(void (*cb)(void* arg), void* arg) {

at_exit_functions_.push_back(ExitCallback{cb, arg});

}

void Environment::RunAndClearNativeImmediates() {

TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),

"RunAndClearNativeImmediates", this);

size_t count = native_immediate_callbacks_.size();

if (count > 0) {

size_t ref_count = 0;

std::vector<NativeImmediateCallback> list;

native_immediate_callbacks_.swap(list);

auto drain_list = [&]() {

TryCatchScope try_catch(this);

for (auto it = list.begin(); it != list.end(); ++it) {

DebugSealHandleScope seal_handle_scope(isolate());

it->cb_(this, it->data_);

if (it->refed_)

ref_count++;

if (UNLIKELY(try_catch.HasCaught())) {

if (!try_catch.HasTerminated())

FatalException(isolate(), try_catch);

// Bail out, remove the already executed callbacks from list

// and set up a new TryCatch for the other pending callbacks.

std::move_backward(it, list.end(), list.begin() + (list.end() - it));

list.resize(list.end() - it);

return true;

}

}

return false;

};

while (drain_list()) {}

DCHECK_GE(immediate_info()->count(), count);

immediate_info()->count_dec(count);

immediate_info()->ref_count_dec(ref_count);

}

}

void Environment::ScheduleTimer(int64_t duration_ms) {

if (started_cleanup_) return;

uv_timer_start(timer_handle(), RunTimers, duration_ms, 0);

}

void Environment::ToggleTimerRef(bool ref) {

if (started_cleanup_) return;

if (ref) {

uv_ref(reinterpret_cast<uv_handle_t*>(timer_handle()));

} else {

uv_unref(reinterpret_cast<uv_handle_t*>(timer_handle()));

}

}

void Environment::RunTimers(uv_timer_t* handle) {

Environment* env = Environment::from_timer_handle(handle);

TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),

"RunTimers", env);

if (!env->can_call_into_js())

return;

HandleScope handle_scope(env->isolate());

Context::Scope context_scope(env->context());

Local<Object> process = env->process_object();

InternalCallbackScope scope(env, process, {0, 0});

Local<Function> cb = env->timers_callback_function();

MaybeLocal<Value> ret;

Local<Value> arg = env->GetNow();

// This code will loop until all currently due timers will process. It is

// impossible for us to end up in an infinite loop due to how the JS-side

// is structured.

do {

TryCatchScope try_catch(env);

try_catch.SetVerbose(true);

ret = cb->Call(env->context(), process, 1, &arg);

} while (ret.IsEmpty() && env->can_call_into_js());

// NOTE(apapirovski): If it ever becomes possible that `call_into_js` above

// is reset back to `true` after being previously set to `false` then this

// code becomes invalid and needs to be rewritten. Otherwise catastrophic

// timers corruption will occur and all timers behaviour will become

// entirely unpredictable.

if (ret.IsEmpty())

return;

// To allow for less JS-C++ boundary crossing, the value returned from JS

// serves a few purposes:

// 1. If it's 0, no more timers exist and the handle should be unrefed

// 2. If it's > 0, the value represents the next timer's expiry and there

// is at least one timer remaining that is refed.

// 3. If it's < 0, the absolute value represents the next timer's expiry

// and there are no timers that are refed.

int64_t expiry_ms =

ret.ToLocalChecked()->IntegerValue(env->context()).FromJust();

uv_handle_t* h = reinterpret_cast<uv_handle_t*>(handle);

if (expiry_ms != 0) {

int64_t duration_ms =

llabs(expiry_ms) - (uv_now(env->event_loop()) - env->timer_base());

env->ScheduleTimer(duration_ms > 0 ? duration_ms : 1);

if (expiry_ms > 0)

uv_ref(h);

else

uv_unref(h);

} else {

uv_unref(h);

}

}

void Environment::CheckImmediate(uv_check_t* handle) {

Environment* env = Environment::from_immediate_check_handle(handle);

TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),

"CheckImmediate", env);

if (env->immediate_info()->count() == 0)

return;

HandleScope scope(env->isolate());

Context::Scope context_scope(env->context());

env->RunAndClearNativeImmediates();

if (!env->can_call_into_js())

return;

do {

MakeCallback(env->isolate(),

env->process_object(),

env->immediate_callback_function(),

0,

nullptr,

{0, 0}).ToLocalChecked();

} while (env->immediate_info()->has_outstanding() && env->can_call_into_js());

if (env->immediate_info()->ref_count() == 0)

env->ToggleImmediateRef(false);

}

void Environment::ToggleImmediateRef(bool ref) {

if (started_cleanup_) return;

if (ref) {

// Idle handle is needed only to stop the event loop from blocking in poll.

uv_idle_start(immediate_idle_handle(), [](uv_idle_t*){ });

} else {

uv_idle_stop(immediate_idle_handle());

}

}

Local<Value> Environment::GetNow() {

uv_update_time(event_loop());

uint64_t now = uv_now(event_loop());

CHECK_GE(now, timer_base());

now -= timer_base();

if (now <= 0xffffffff)

return Integer::NewFromUnsigned(isolate(), static_cast<uint32_t>(now));

else

return Number::New(isolate(), static_cast<double>(now));

}

void Environment::set_debug_categories(const std::string& cats, bool enabled) {

std::string debug_categories = cats;

while (!debug_categories.empty()) {

std::string::size_type comma_pos = debug_categories.find(',');

std::string wanted = ToLower(debug_categories.substr(0, comma_pos));

#define V(name) \

{ \

static const std::string available_category = ToLower(#name); \

if (available_category.find(wanted) != std::string::npos) \

set_debug_enabled(DebugCategory::name, enabled); \

}

DEBUG_CATEGORY_NAMES(V)

#undef V

if (comma_pos == std::string::npos)

break;

// Use everything after the `,` as the list for the next iteration.

debug_categories = debug_categories.substr(comma_pos + 1);

}

}

void CollectExceptionInfo(Environment* env,

Local<Object> obj,

int errorno,

const char* err_string,

const char* syscall,

const char* message,

const char* path,

const char* dest) {

obj->Set(env->context(),

env->errno_string(),

Integer::New(env->isolate(), errorno)).Check();

obj->Set(env->context(), env->code_string(),

OneByteString(env->isolate(), err_string)).Check();

if (message != nullptr) {

obj->Set(env->context(), env->message_string(),

OneByteString(env->isolate(), message)).Check();

}

Local<Value> path_buffer;

if (path != nullptr) {

path_buffer =

Buffer::Copy(env->isolate(), path, strlen(path)).ToLocalChecked();

obj->Set(env->context(), env->path_string(), path_buffer).Check();

}

Local<Value> dest_buffer;

if (dest != nullptr) {

dest_buffer =

Buffer::Copy(env->isolate(), dest, strlen(dest)).ToLocalChecked();

obj->Set(env->context(), env->dest_string(), dest_buffer).Check();

}

if (syscall != nullptr) {

obj->Set(env->context(), env->syscall_string(),

OneByteString(env->isolate(), syscall)).Check();

}

}

void Environment::CollectUVExceptionInfo(Local<Value> object,

int errorno,

const char* syscall,

const char* message,

const char* path,

const char* dest) {

if (!object->IsObject() || errorno == 0)

return;

Local<Object> obj = object.As<Object>();

const char* err_string = uv_err_name(errorno);

if (message == nullptr || message[0] == '\0') {

message = uv_strerror(errorno);

}

node::CollectExceptionInfo(this, obj, errorno, err_string,

syscall, message, path, dest);

}

void ImmediateInfo::MemoryInfo(MemoryTracker* tracker) const {

tracker->TrackField("fields", fields_);

}

void TickInfo::MemoryInfo(MemoryTracker* tracker) const {

tracker->TrackField("fields", fields_);

}

void AsyncHooks::MemoryInfo(MemoryTracker* tracker) const {

tracker->TrackField("providers", providers_);

tracker->TrackField("async_ids_stack", async_ids_stack_);

tracker->TrackField("fields", fields_);

tracker->TrackField("async_id_fields", async_id_fields_);

}

void AsyncHooks::grow_async_ids_stack() {

async_ids_stack_.reserve(async_ids_stack_.Length() * 3);

env()->async_hooks_binding()->Set(

env()->context(),

env()->async_ids_stack_string(),

async_ids_stack_.GetJSArray()).Check();

}

uv_key_t Environment::thread_local_env = {};

void Environment::Exit(int exit_code) {

if (is_main_thread()) {

stop_sub_worker_contexts();

DisposePlatform();

exit(exit_code);

} else {

worker_context_->Exit(exit_code);

}

}

void Environment::stop_sub_worker_contexts() {

while (!sub_worker_contexts_.empty()) {

Worker* w = *sub_worker_contexts_.begin();

remove_sub_worker_context(w);

w->Exit(1);

w->JoinThread();

}

}

#if HAVE_INSPECTOR

#endif // HAVE_INSPECTOR

void MemoryTracker::TrackField(const char* edge_name,

const CleanupHookCallback& value,

const char* node_name) {

v8::HandleScope handle_scope(isolate_);

// Here, we utilize the fact that CleanupHookCallback instances

// are all unique and won't be tracked twice in one BuildEmbedderGraph

// callback.

MemoryRetainerNode* n =

PushNode("CleanupHookCallback", sizeof(value), edge_name);

// TODO(joyeecheung): at the moment only arguments of type BaseObject will be

// identified and tracked here (based on their deleters),

// but we may convert and track other known types here.

BaseObject* obj = value.GetBaseObject();

if (obj != nullptr) {

this->TrackField("arg", obj);

}

CHECK_EQ(CurrentNode(), n);

CHECK_NE(n->size_, 0);

PopNode();

}

void Environment::BuildEmbedderGraph(Isolate* isolate,

EmbedderGraph* graph,

void* data) {

MemoryTracker tracker(isolate, graph);

Environment* env = static_cast<Environment*>(data);

tracker.Track(env);

}

inline size_t Environment::SelfSize() const {

size_t size = sizeof(*this);

// Remove non pointer fields that will be tracked in MemoryInfo()

// TODO(joyeecheung): refactor the MemoryTracker interface so

// this can be done for common types within the Track* calls automatically

// if a certain scope is entered.

size -= sizeof(thread_stopper_);

size -= sizeof(async_hooks_);

size -= sizeof(tick_info_);

size -= sizeof(immediate_info_);

return size;

}

void Environment::MemoryInfo(MemoryTracker* tracker) const {

// Iteratable STLs have their own sizes subtracted from the parent

// by default.

tracker->TrackField("isolate_data", isolate_data_);

tracker->TrackField("native_modules_with_cache", native_modules_with_cache);

tracker->TrackField("native_modules_without_cache",

native_modules_without_cache);

tracker->TrackField("destroy_async_id_list", destroy_async_id_list_);

tracker->TrackField("exec_argv", exec_argv_);

tracker->TrackField("should_abort_on_uncaught_toggle",

should_abort_on_uncaught_toggle_);

tracker->TrackField("stream_base_state", stream_base_state_);

tracker->TrackField("fs_stats_field_array", fs_stats_field_array_);

tracker->TrackField("fs_stats_field_bigint_array",

fs_stats_field_bigint_array_);

tracker->TrackField("thread_stopper", thread_stopper_);

tracker->TrackField("cleanup_hooks", cleanup_hooks_);

tracker->TrackField("async_hooks", async_hooks_);

tracker->TrackField("immediate_info", immediate_info_);

tracker->TrackField("tick_info", tick_info_);

#define V(PropertyName, TypeName) \

tracker->TrackField(#PropertyName, PropertyName());

ENVIRONMENT_STRONG_PERSISTENT_VALUES(V)

#undef V

// FIXME(joyeecheung): track other fields in Environment.

// Currently MemoryTracker is unable to track these

// correctly:

// - Internal types that do not implement MemoryRetainer yet

// - STL containers with MemoryRetainer* inside

// - STL containers with numeric types inside that should not have their

// nodes elided e.g. numeric keys in maps.

// We also need to make sure that when we add a non-pointer field as its own

// node, we shift its sizeof() size out of the Environment node.

}