Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	node_watchdog.cc	Lines:	167	198	84.3 %
Date:	2022-08-14 04:19:53	Branches:	37	68	54.4 %


// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

#include <algorithm>

#include "async_wrap-inl.h"
#include "debug_utils-inl.h"
#include "env-inl.h"
#include "node_errors.h"
#include "node_internals.h"
#include "node_watchdog.h"
#include "util-inl.h"

namespace node {

using v8::Context;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::Isolate;
using v8::Local;
using v8::Object;
using v8::Value;

Watchdog::Watchdog(v8::Isolate* isolate, uint64_t ms, bool* timed_out)
    : isolate_(isolate), timed_out_(timed_out) {

  int rc;
  rc = uv_loop_init(&loop_);
  if (rc != 0) {
    FatalError("node::Watchdog::Watchdog()",
               "Failed to initialize uv loop.");
  }

  rc = uv_async_init(&loop_, &async_, [](uv_async_t* signal) {
    Watchdog* w = ContainerOf(&Watchdog::async_, signal);
    uv_stop(&w->loop_);
  });

  CHECK_EQ(0, rc);

  rc = uv_timer_init(&loop_, &timer_);
  CHECK_EQ(0, rc);

  rc = uv_timer_start(&timer_, &Watchdog::Timer, ms, 0);
  CHECK_EQ(0, rc);

  rc = uv_thread_create(&thread_, &Watchdog::Run, this);
  CHECK_EQ(0, rc);
}


Watchdog::~Watchdog() {
  uv_async_send(&async_);
  uv_thread_join(&thread_);

  uv_close(reinterpret_cast<uv_handle_t*>(&async_), nullptr);

  // UV_RUN_DEFAULT so that libuv has a chance to clean up.
  uv_run(&loop_, UV_RUN_DEFAULT);

  CheckedUvLoopClose(&loop_);
}


void Watchdog::Run(void* arg) {
  Watchdog* wd = static_cast<Watchdog*>(arg);

  // UV_RUN_DEFAULT the loop will be stopped either by the async or the
  // timer handle.
  uv_run(&wd->loop_, UV_RUN_DEFAULT);

  // Loop ref count reaches zero when both handles are closed.
  // Close the timer handle on this side and let ~Watchdog() close async_
  uv_close(reinterpret_cast<uv_handle_t*>(&wd->timer_), nullptr);
}

void Watchdog::Timer(uv_timer_t* timer) {
  Watchdog* w = ContainerOf(&Watchdog::timer_, timer);
  *w->timed_out_ = true;
  w->isolate()->TerminateExecution();
  uv_stop(&w->loop_);
}


SigintWatchdog::SigintWatchdog(
  v8::Isolate* isolate, bool* received_signal)
    : isolate_(isolate), received_signal_(received_signal) {
  Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
  // Register this watchdog with the global SIGINT/Ctrl+C listener.
  SigintWatchdogHelper::GetInstance()->Register(this);
  // Start the helper thread, if that has not already happened.
  SigintWatchdogHelper::GetInstance()->Start();
}


SigintWatchdog::~SigintWatchdog() {
  Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
  SigintWatchdogHelper::GetInstance()->Unregister(this);
  SigintWatchdogHelper::GetInstance()->Stop();
}

SignalPropagation SigintWatchdog::HandleSigint() {
  *received_signal_ = true;
  isolate_->TerminateExecution();
  return SignalPropagation::kStopPropagation;
}

void TraceSigintWatchdog::Init(Environment* env, Local<Object> target) {
  Isolate* isolate = env->isolate();
  Local<FunctionTemplate> constructor = NewFunctionTemplate(isolate, New);
  constructor->InstanceTemplate()->SetInternalFieldCount(
      TraceSigintWatchdog::kInternalFieldCount);
  constructor->Inherit(HandleWrap::GetConstructorTemplate(env));

  SetProtoMethod(isolate, constructor, "start", Start);
  SetProtoMethod(isolate, constructor, "stop", Stop);

  SetConstructorFunction(
      env->context(), target, "TraceSigintWatchdog", constructor);
}

void TraceSigintWatchdog::New(const FunctionCallbackInfo<Value>& args) {
  // This constructor should not be exposed to public javascript.
  // Therefore we assert that we are not trying to call this as a
  // normal function.
  CHECK(args.IsConstructCall());
  Environment* env = Environment::GetCurrent(args);
  new TraceSigintWatchdog(env, args.This());
}

void TraceSigintWatchdog::Start(const FunctionCallbackInfo<Value>& args) {
  TraceSigintWatchdog* watchdog;
  ASSIGN_OR_RETURN_UNWRAP(&watchdog, args.Holder());
  Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
  // Register this watchdog with the global SIGINT/Ctrl+C listener.
  SigintWatchdogHelper::GetInstance()->Register(watchdog);
  // Start the helper thread, if that has not already happened.
  int r = SigintWatchdogHelper::GetInstance()->Start();
  CHECK_EQ(r, 0);
}

void TraceSigintWatchdog::Stop(const FunctionCallbackInfo<Value>& args) {
  TraceSigintWatchdog* watchdog;
  ASSIGN_OR_RETURN_UNWRAP(&watchdog, args.Holder());
  Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
  SigintWatchdogHelper::GetInstance()->Unregister(watchdog);
  SigintWatchdogHelper::GetInstance()->Stop();
}

TraceSigintWatchdog::TraceSigintWatchdog(Environment* env, Local<Object> object)
    : HandleWrap(env,
                 object,
                 reinterpret_cast<uv_handle_t*>(&handle_),
                 AsyncWrap::PROVIDER_SIGINTWATCHDOG) {
  int r = uv_async_init(env->event_loop(), &handle_, [](uv_async_t* handle) {
    TraceSigintWatchdog* watchdog =
        ContainerOf(&TraceSigintWatchdog::handle_, handle);
    watchdog->signal_flag_ = SignalFlags::FromIdle;
    watchdog->HandleInterrupt();
  });
  CHECK_EQ(r, 0);
  uv_unref(reinterpret_cast<uv_handle_t*>(&handle_));
}

SignalPropagation TraceSigintWatchdog::HandleSigint() {
  /**
   * In case of uv loop polling, i.e. no JS currently running, activate the
   * loop to run a piece of JS code to trigger interruption.
   */
  CHECK_EQ(uv_async_send(&handle_), 0);
  env()->isolate()->RequestInterrupt(
      [](v8::Isolate* isolate, void* data) {
        TraceSigintWatchdog* self = static_cast<TraceSigintWatchdog*>(data);
        if (self->signal_flag_ == SignalFlags::None) {
          self->signal_flag_ = SignalFlags::FromInterrupt;
        }
        self->HandleInterrupt();
      },
      this);
  return SignalPropagation::kContinuePropagation;
}

void TraceSigintWatchdog::HandleInterrupt() {
  // Do not nest interrupts.
  if (interrupting) {
    return;
  }
  interrupting = true;
  if (signal_flag_ == SignalFlags::None) {
    return;
  }
  Environment* env_ = env();
  // FIXME: Before
  // https://github.com/nodejs/node/pull/29207#issuecomment-527667993 get
  // fixed, additional JavaScript code evaluation shall be prevented from
  // running during interruption.
  FPrintF(stderr,
      "KEYBOARD_INTERRUPT: Script execution was interrupted by `SIGINT`\n");
  if (signal_flag_ == SignalFlags::FromInterrupt) {
    PrintStackTrace(env_->isolate(),
                    v8::StackTrace::CurrentStackTrace(
                        env_->isolate(), 10, v8::StackTrace::kDetailed));
  }
  signal_flag_ = SignalFlags::None;
  interrupting = false;

  Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
  SigintWatchdogHelper::GetInstance()->Unregister(this);
  SigintWatchdogHelper::GetInstance()->Stop();
  raise(SIGINT);
}

#ifdef __POSIX__
void* SigintWatchdogHelper::RunSigintWatchdog(void* arg) {
  // Inside the helper thread.
  bool is_stopping;

  do {
    uv_sem_wait(&instance.sem_);
    is_stopping = InformWatchdogsAboutSignal();
  } while (!is_stopping);

  return nullptr;
}

void SigintWatchdogHelper::HandleSignal(int signum,
                                        siginfo_t* info,
                                        void* ucontext) {
  uv_sem_post(&instance.sem_);
}

#else

// Windows starts a separate thread for executing the handler, so no extra
// helper thread is required.
BOOL WINAPI SigintWatchdogHelper::WinCtrlCHandlerRoutine(DWORD dwCtrlType) {
  if (!instance.watchdog_disabled_ &&
      (dwCtrlType == CTRL_C_EVENT || dwCtrlType == CTRL_BREAK_EVENT)) {
    InformWatchdogsAboutSignal();

    // Return true because the signal has been handled.
    return TRUE;
  } else {
    return FALSE;
  }
}
#endif


bool SigintWatchdogHelper::InformWatchdogsAboutSignal() {
  Mutex::ScopedLock list_lock(instance.list_mutex_);

  bool is_stopping = false;
#ifdef __POSIX__
  is_stopping = instance.stopping_;
#endif

  // If there are no listeners and the helper thread has been awoken by a signal
  // (= not when stopping it), indicate that by setting has_pending_signal_.
  if (instance.watchdogs_.empty() && !is_stopping) {
    instance.has_pending_signal_ = true;
  }

  for (auto it = instance.watchdogs_.rbegin(); it != instance.watchdogs_.rend();
       it++) {
    SignalPropagation wp = (*it)->HandleSigint();
    if (wp == SignalPropagation::kStopPropagation) {
      break;
    }
  }

  return is_stopping;
}


int SigintWatchdogHelper::Start() {
  Mutex::ScopedLock lock(mutex_);

  if (start_stop_count_++ > 0) {
    return 0;
  }

#ifdef __POSIX__
  CHECK_EQ(has_running_thread_, false);
  has_pending_signal_ = false;
  stopping_ = false;

  sigset_t sigmask;
  sigfillset(&sigmask);
  sigset_t savemask;
  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, &savemask));
  sigmask = savemask;
  int ret = pthread_create(&thread_, nullptr, RunSigintWatchdog, nullptr);
  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
  if (ret != 0) {
    return ret;
  }
  has_running_thread_ = true;

  RegisterSignalHandler(SIGINT, HandleSignal);
#else
  if (watchdog_disabled_) {
    watchdog_disabled_ = false;
  } else {
    SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, TRUE);
  }
#endif

  return 0;
}


bool SigintWatchdogHelper::Stop() {
  bool had_pending_signal;
  Mutex::ScopedLock lock(mutex_);

  {
    Mutex::ScopedLock list_lock(list_mutex_);

    had_pending_signal = has_pending_signal_;

    if (--start_stop_count_ > 0) {
      has_pending_signal_ = false;
      return had_pending_signal;
    }

#ifdef __POSIX__
    // Set stopping now because it's only protected by list_mutex_.
    stopping_ = true;
#endif

    watchdogs_.clear();
  }

#ifdef __POSIX__
  if (!has_running_thread_) {
    has_pending_signal_ = false;
    return had_pending_signal;
  }

  // Wake up the helper thread.
  uv_sem_post(&sem_);

  // Wait for the helper thread to finish.
  CHECK_EQ(0, pthread_join(thread_, nullptr));
  has_running_thread_ = false;

  RegisterSignalHandler(SIGINT, SignalExit, true);
#else
  watchdog_disabled_ = true;
#endif

  had_pending_signal = has_pending_signal_;
  has_pending_signal_ = false;

  return had_pending_signal;
}


bool SigintWatchdogHelper::HasPendingSignal() {
  Mutex::ScopedLock lock(list_mutex_);

  return has_pending_signal_;
}

void SigintWatchdogHelper::Register(SigintWatchdogBase* wd) {
  Mutex::ScopedLock lock(list_mutex_);

  watchdogs_.push_back(wd);
}

void SigintWatchdogHelper::Unregister(SigintWatchdogBase* wd) {
  Mutex::ScopedLock lock(list_mutex_);

  auto it = std::find(watchdogs_.begin(), watchdogs_.end(), wd);

  CHECK_NE(it, watchdogs_.end());
  watchdogs_.erase(it);
}


SigintWatchdogHelper::SigintWatchdogHelper()
    : start_stop_count_(0),
      has_pending_signal_(false) {
#ifdef __POSIX__
  has_running_thread_ = false;
  stopping_ = false;
  CHECK_EQ(0, uv_sem_init(&sem_, 0));
#else
  watchdog_disabled_ = false;
#endif
}


SigintWatchdogHelper::~SigintWatchdogHelper() {
  start_stop_count_ = 0;
  Stop();

#ifdef __POSIX__
  CHECK_EQ(has_running_thread_, false);
  uv_sem_destroy(&sem_);
#endif
}

SigintWatchdogHelper SigintWatchdogHelper::instance;
Mutex SigintWatchdogHelper::instance_action_mutex_;

namespace watchdog {
static void Initialize(Local<Object> target,
                       Local<Value> unused,
                       Local<Context> context,
                       void* priv) {
  Environment* env = Environment::GetCurrent(context);
  TraceSigintWatchdog::Init(env, target);
}
}  // namespace watchdog

}  // namespace node

NODE_MODULE_CONTEXT_AWARE_INTERNAL(watchdog, node::watchdog::Initialize)


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			// Copyright Joyent, Inc. and other Node contributors.
2			//
3			// Permission is hereby granted, free of charge, to any person obtaining a
4			// copy of this software and associated documentation files (the
5			// "Software"), to deal in the Software without restriction, including
6			// without limitation the rights to use, copy, modify, merge, publish,
7			// distribute, sublicense, and/or sell copies of the Software, and to permit
8			// persons to whom the Software is furnished to do so, subject to the
9			// following conditions:
10			//
11			// The above copyright notice and this permission notice shall be included
12			// in all copies or substantial portions of the Software.
13			//
14			// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15			// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
16			// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
17			// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
18			// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
19			// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
20			// USE OR OTHER DEALINGS IN THE SOFTWARE.
21
22			#include <algorithm>
23
24			#include "async_wrap-inl.h"
25			#include "debug_utils-inl.h"
26			#include "env-inl.h"
27			#include "node_errors.h"
28			#include "node_internals.h"
29			#include "node_watchdog.h"
30			#include "util-inl.h"
31
32			namespace node {
33
34			using v8::Context;
35			using v8::FunctionCallbackInfo;
36			using v8::FunctionTemplate;
37			using v8::Isolate;
38			using v8::Local;
39			using v8::Object;
40			using v8::Value;
41
42		18	Watchdog::Watchdog(v8::Isolate* isolate, uint64_t ms, bool* timed_out)
43		18	: isolate_(isolate), timed_out_(timed_out) {
44
45			int rc;
46		18	rc = uv_loop_init(&loop_);
47	✗✓	18	if (rc != 0) {
48			FatalError("node::Watchdog::Watchdog()",
49			"Failed to initialize uv loop.");
50			}
51
52		18	rc = uv_async_init(&loop_, &async_, [](uv_async_t* signal) {
53		5	Watchdog* w = ContainerOf(&Watchdog::async_, signal);
54		5	uv_stop(&w->loop_);
55		5	});
56
57	✗✓	18	CHECK_EQ(0, rc);
58
59		18	rc = uv_timer_init(&loop_, &timer_);
60	✗✓	18	CHECK_EQ(0, rc);
61
62		18	rc = uv_timer_start(&timer_, &Watchdog::Timer, ms, 0);
63	✗✓	18	CHECK_EQ(0, rc);
64
65		18	rc = uv_thread_create(&thread_, &Watchdog::Run, this);
66	✗✓	18	CHECK_EQ(0, rc);
67		18	}
68
69
70		36	Watchdog::~Watchdog() {
71		18	uv_async_send(&async_);
72		18	uv_thread_join(&thread_);
73
74		18	uv_close(reinterpret_cast<uv_handle_t*>(&async_), nullptr);
75
76			// UV_RUN_DEFAULT so that libuv has a chance to clean up.
77		18	uv_run(&loop_, UV_RUN_DEFAULT);
78
79		18	CheckedUvLoopClose(&loop_);
80		18	}
81
82
83		18	void Watchdog::Run(void* arg) {
84		18	Watchdog* wd = static_cast<Watchdog*>(arg);
85
86			// UV_RUN_DEFAULT the loop will be stopped either by the async or the
87			// timer handle.
88		18	uv_run(&wd->loop_, UV_RUN_DEFAULT);
89
90			// Loop ref count reaches zero when both handles are closed.
91			// Close the timer handle on this side and let ~Watchdog() close async_
92		18	uv_close(reinterpret_cast<uv_handle_t*>(&wd->timer_), nullptr);
93		18	}
94
95		13	void Watchdog::Timer(uv_timer_t* timer) {
96		13	Watchdog* w = ContainerOf(&Watchdog::timer_, timer);
97		13	*w->timed_out_ = true;
98		13	w->isolate()->TerminateExecution();
99		13	uv_stop(&w->loop_);
100		13	}
101
102
103		1198	SigintWatchdog::SigintWatchdog(
104		1198	v8::Isolate* isolate, bool* received_signal)
105		1198	: isolate_(isolate), received_signal_(received_signal) {
106		2396	Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
107			// Register this watchdog with the global SIGINT/Ctrl+C listener.
108		1198	SigintWatchdogHelper::GetInstance()->Register(this);
109			// Start the helper thread, if that has not already happened.
110		1198	SigintWatchdogHelper::GetInstance()->Start();
111		1198	}
112
113
114		2390	SigintWatchdog::~SigintWatchdog() {
115		4780	Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
116		2390	SigintWatchdogHelper::GetInstance()->Unregister(this);
117		2390	SigintWatchdogHelper::GetInstance()->Stop();
118			}
119
120		11	SignalPropagation SigintWatchdog::HandleSigint() {
121		11	*received_signal_ = true;
122		11	isolate_->TerminateExecution();
123		11	return SignalPropagation::kStopPropagation;
124			}
125
126		2	void TraceSigintWatchdog::Init(Environment* env, Local<Object> target) {
127		2	Isolate* isolate = env->isolate();
128		2	Local<FunctionTemplate> constructor = NewFunctionTemplate(isolate, New);
129		4	constructor->InstanceTemplate()->SetInternalFieldCount(
130			TraceSigintWatchdog::kInternalFieldCount);
131		2	constructor->Inherit(HandleWrap::GetConstructorTemplate(env));
132
133		2	SetProtoMethod(isolate, constructor, "start", Start);
134		2	SetProtoMethod(isolate, constructor, "stop", Stop);
135
136		2	SetConstructorFunction(
137			env->context(), target, "TraceSigintWatchdog", constructor);
138		2	}
139
140		1	void TraceSigintWatchdog::New(const FunctionCallbackInfo<Value>& args) {
141			// This constructor should not be exposed to public javascript.
142			// Therefore we assert that we are not trying to call this as a
143			// normal function.
144	✗✓	1	CHECK(args.IsConstructCall());
145		1	Environment* env = Environment::GetCurrent(args);
146		1	new TraceSigintWatchdog(env, args.This());
147		1	}
148
149		2	void TraceSigintWatchdog::Start(const FunctionCallbackInfo<Value>& args) {
150			TraceSigintWatchdog* watchdog;
151	✗✓	2	ASSIGN_OR_RETURN_UNWRAP(&watchdog, args.Holder());
152		4	Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
153			// Register this watchdog with the global SIGINT/Ctrl+C listener.
154	✓✗	2	SigintWatchdogHelper::GetInstance()->Register(watchdog);
155			// Start the helper thread, if that has not already happened.
156		2	int r = SigintWatchdogHelper::GetInstance()->Start();
157	✗✓	2	CHECK_EQ(r, 0);
158			}
159
160		2	void TraceSigintWatchdog::Stop(const FunctionCallbackInfo<Value>& args) {
161			TraceSigintWatchdog* watchdog;
162	✗✓	2	ASSIGN_OR_RETURN_UNWRAP(&watchdog, args.Holder());
163		4	Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
164	✓✗	2	SigintWatchdogHelper::GetInstance()->Unregister(watchdog);
165		2	SigintWatchdogHelper::GetInstance()->Stop();
166			}
167
168		1	TraceSigintWatchdog::TraceSigintWatchdog(Environment* env, Local<Object> object)
169			: HandleWrap(env,
170			object,
171		1	reinterpret_cast<uv_handle_t*>(&handle_),
172		1	AsyncWrap::PROVIDER_SIGINTWATCHDOG) {
173		1	int r = uv_async_init(env->event_loop(), &handle_, [](uv_async_t* handle) {
174			TraceSigintWatchdog* watchdog =
175			ContainerOf(&TraceSigintWatchdog::handle_, handle);
176			watchdog->signal_flag_ = SignalFlags::FromIdle;
177			watchdog->HandleInterrupt();
178		1	});
179	✗✓	1	CHECK_EQ(r, 0);
180		1	uv_unref(reinterpret_cast<uv_handle_t*>(&handle_));
181		1	}
182
183			SignalPropagation TraceSigintWatchdog::HandleSigint() {
184			/**
185			* In case of uv loop polling, i.e. no JS currently running, activate the
186			* loop to run a piece of JS code to trigger interruption.
187			*/
188			CHECK_EQ(uv_async_send(&handle_), 0);
189			env()->isolate()->RequestInterrupt(
190			[](v8::Isolate* isolate, void* data) {
191			TraceSigintWatchdog* self = static_cast<TraceSigintWatchdog*>(data);
192			if (self->signal_flag_ == SignalFlags::None) {
193			self->signal_flag_ = SignalFlags::FromInterrupt;
194			}
195			self->HandleInterrupt();
196			},
197			this);
198			return SignalPropagation::kContinuePropagation;
199			}
200
201			void TraceSigintWatchdog::HandleInterrupt() {
202			// Do not nest interrupts.
203			if (interrupting) {
204			return;
205			}
206			interrupting = true;
207			if (signal_flag_ == SignalFlags::None) {
208			return;
209			}
210			Environment* env_ = env();
211			// FIXME: Before
212			// https://github.com/nodejs/node/pull/29207#issuecomment-527667993 get
213			// fixed, additional JavaScript code evaluation shall be prevented from
214			// running during interruption.
215			FPrintF(stderr,
216			"KEYBOARD_INTERRUPT: Script execution was interrupted by `SIGINT`\n");
217			if (signal_flag_ == SignalFlags::FromInterrupt) {
218			PrintStackTrace(env_->isolate(),
219			v8::StackTrace::CurrentStackTrace(
220			env_->isolate(), 10, v8::StackTrace::kDetailed));
221			}
222			signal_flag_ = SignalFlags::None;
223			interrupting = false;
224
225			Mutex::ScopedLock lock(SigintWatchdogHelper::GetInstanceActionMutex());
226			SigintWatchdogHelper::GetInstance()->Unregister(this);
227			SigintWatchdogHelper::GetInstance()->Stop();
228			raise(SIGINT);
229			}
230
231			#ifdef __POSIX__
232		523	void* SigintWatchdogHelper::RunSigintWatchdog(void* arg) {
233			// Inside the helper thread.
234			bool is_stopping;
235
236		14	do {
237		523	uv_sem_wait(&instance.sem_);
238		523	is_stopping = InformWatchdogsAboutSignal();
239	✓✓	523	} while (!is_stopping);
240
241		509	return nullptr;
242			}
243
244		14	void SigintWatchdogHelper::HandleSignal(int signum,
245			siginfo_t* info,
246			void* ucontext) {
247		14	uv_sem_post(&instance.sem_);
248		14	}
249
250			#else
251
252			// Windows starts a separate thread for executing the handler, so no extra
253			// helper thread is required.
254			BOOL WINAPI SigintWatchdogHelper::WinCtrlCHandlerRoutine(DWORD dwCtrlType) {
255			if (!instance.watchdog_disabled_ &&
256			(dwCtrlType == CTRL_C_EVENT \|\| dwCtrlType == CTRL_BREAK_EVENT)) {
257			InformWatchdogsAboutSignal();
258
259			// Return true because the signal has been handled.
260			return TRUE;
261			} else {
262			return FALSE;
263			}
264			}
265			#endif
266
267
268		523	bool SigintWatchdogHelper::InformWatchdogsAboutSignal() {
269		523	Mutex::ScopedLock list_lock(instance.list_mutex_);
270
271		523	bool is_stopping = false;
272			#ifdef __POSIX__
273		523	is_stopping = instance.stopping_;
274			#endif
275
276			// If there are no listeners and the helper thread has been awoken by a signal
277			// (= not when stopping it), indicate that by setting has_pending_signal_.
278	✓✓✓✓ ✓✓	523	if (instance.watchdogs_.empty() && !is_stopping) {
279		3	instance.has_pending_signal_ = true;
280			}
281
282	✓✓	523	for (auto it = instance.watchdogs_.rbegin(); it != instance.watchdogs_.rend();
283			it++) {
284		11	SignalPropagation wp = (*it)->HandleSigint();
285	✓✗	11	if (wp == SignalPropagation::kStopPropagation) {
286		11	break;
287			}
288			}
289
290		523	return is_stopping;
291			}
292
293
294		1395	int SigintWatchdogHelper::Start() {
295		2790	Mutex::ScopedLock lock(mutex_);
296
297	✓✓	1395	if (start_stop_count_++ > 0) {
298		886	return 0;
299			}
300
301			#ifdef __POSIX__
302	✗✓	509	CHECK_EQ(has_running_thread_, false);
303		509	has_pending_signal_ = false;
304		509	stopping_ = false;
305
306			sigset_t sigmask;
307		509	sigfillset(&sigmask);
308			sigset_t savemask;
309	✗✓	509	CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, &savemask));
310		509	sigmask = savemask;
311		509	int ret = pthread_create(&thread_, nullptr, RunSigintWatchdog, nullptr);
312	✗✓	509	CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
313	✗✓	509	if (ret != 0) {
314			return ret;
315			}
316		509	has_running_thread_ = true;
317
318		509	RegisterSignalHandler(SIGINT, HandleSignal);
319			#else
320			if (watchdog_disabled_) {
321			watchdog_disabled_ = false;
322			} else {
323			SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, TRUE);
324			}
325			#endif
326
327		509	return 0;
328			}
329
330
331		6710	bool SigintWatchdogHelper::Stop() {
332			bool had_pending_signal;
333		13420	Mutex::ScopedLock lock(mutex_);
334
335			{
336		6710	Mutex::ScopedLock list_lock(list_mutex_);
337
338		6710	had_pending_signal = has_pending_signal_;
339
340	✓✓	6710	if (--start_stop_count_ > 0) {
341		883	has_pending_signal_ = false;
342		883	return had_pending_signal;
343			}
344
345			#ifdef __POSIX__
346			// Set stopping now because it's only protected by list_mutex_.
347		5827	stopping_ = true;
348			#endif
349
350		5827	watchdogs_.clear();
351			}
352
353			#ifdef __POSIX__
354	✓✓	5827	if (!has_running_thread_) {
355		5318	has_pending_signal_ = false;
356		5318	return had_pending_signal;
357			}
358
359			// Wake up the helper thread.
360		509	uv_sem_post(&sem_);
361
362			// Wait for the helper thread to finish.
363	✗✓	509	CHECK_EQ(0, pthread_join(thread_, nullptr));
364		509	has_running_thread_ = false;
365
366		509	RegisterSignalHandler(SIGINT, SignalExit, true);
367			#else
368			watchdog_disabled_ = true;
369			#endif
370
371		509	had_pending_signal = has_pending_signal_;
372		509	has_pending_signal_ = false;
373
374		509	return had_pending_signal;
375			}
376
377
378		3	bool SigintWatchdogHelper::HasPendingSignal() {
379		3	Mutex::ScopedLock lock(list_mutex_);
380
381		3	return has_pending_signal_;
382			}
383
384		1200	void SigintWatchdogHelper::Register(SigintWatchdogBase* wd) {
385		2400	Mutex::ScopedLock lock(list_mutex_);
386
387		1200	watchdogs_.push_back(wd);
388		1200	}
389
390		1197	void SigintWatchdogHelper::Unregister(SigintWatchdogBase* wd) {
391		1197	Mutex::ScopedLock lock(list_mutex_);
392
393		1197	auto it = std::find(watchdogs_.begin(), watchdogs_.end(), wd);
394
395	✗✓	1197	CHECK_NE(it, watchdogs_.end());
396		1197	watchdogs_.erase(it);
397		1197	}
398
399
400		5321	SigintWatchdogHelper::SigintWatchdogHelper()
401			: start_stop_count_(0),
402		5321	has_pending_signal_(false) {
403			#ifdef __POSIX__
404		5321	has_running_thread_ = false;
405		5321	stopping_ = false;
406	✗✓	5321	CHECK_EQ(0, uv_sem_init(&sem_, 0));
407			#else
408			watchdog_disabled_ = false;
409			#endif
410		5321	}
411
412
413		5321	SigintWatchdogHelper::~SigintWatchdogHelper() {
414		5321	start_stop_count_ = 0;
415		5321	Stop();
416
417			#ifdef __POSIX__
418	✗✓	5321	CHECK_EQ(has_running_thread_, false);
419		5321	uv_sem_destroy(&sem_);
420			#endif
421		5321	}
422
423			SigintWatchdogHelper SigintWatchdogHelper::instance;
424			Mutex SigintWatchdogHelper::instance_action_mutex_;
425
426			namespace watchdog {
427		2	static void Initialize(Local<Object> target,
428			Local<Value> unused,
429			Local<Context> context,
430			void* priv) {
431		2	Environment* env = Environment::GetCurrent(context);
432		2	TraceSigintWatchdog::Init(env, target);
433		2	}
434			} // namespace watchdog
435
436			} // namespace node
437
438		5321	NODE_MODULE_CONTEXT_AWARE_INTERNAL(watchdog, node::watchdog::Initialize)