Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	node_watchdog.cc	Lines:	162	192	84.4 %
Date:	2022-05-23 04:15:47	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::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) {
  // 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() {
  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) {
  Local<FunctionTemplate> constructor = env->NewFunctionTemplate(New);
  constructor->InstanceTemplate()->SetInternalFieldCount(
      TraceSigintWatchdog::kInternalFieldCount);
  constructor->Inherit(HandleWrap::GetConstructorTemplate(env));

  env->SetProtoMethod(constructor, "start", Start);
  env->SetProtoMethod(constructor, "stop", Stop);

  env->SetConstructorFunction(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());
  // 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());
  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;

  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;

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::Local;
38			using v8::Object;
39			using v8::Value;
40
41		18	Watchdog::Watchdog(v8::Isolate* isolate, uint64_t ms, bool* timed_out)
42		18	: isolate_(isolate), timed_out_(timed_out) {
43
44			int rc;
45		18	rc = uv_loop_init(&loop_);
46	✗✓	18	if (rc != 0) {
47			FatalError("node::Watchdog::Watchdog()",
48			"Failed to initialize uv loop.");
49			}
50
51		18	rc = uv_async_init(&loop_, &async_, [](uv_async_t* signal) {
52		5	Watchdog* w = ContainerOf(&Watchdog::async_, signal);
53		5	uv_stop(&w->loop_);
54		5	});
55
56	✗✓	18	CHECK_EQ(0, rc);
57
58		18	rc = uv_timer_init(&loop_, &timer_);
59	✗✓	18	CHECK_EQ(0, rc);
60
61		18	rc = uv_timer_start(&timer_, &Watchdog::Timer, ms, 0);
62	✗✓	18	CHECK_EQ(0, rc);
63
64		18	rc = uv_thread_create(&thread_, &Watchdog::Run, this);
65	✗✓	18	CHECK_EQ(0, rc);
66		18	}
67
68
69		36	Watchdog::~Watchdog() {
70		18	uv_async_send(&async_);
71		18	uv_thread_join(&thread_);
72
73		18	uv_close(reinterpret_cast<uv_handle_t*>(&async_), nullptr);
74
75			// UV_RUN_DEFAULT so that libuv has a chance to clean up.
76		18	uv_run(&loop_, UV_RUN_DEFAULT);
77
78		18	CheckedUvLoopClose(&loop_);
79		18	}
80
81
82		18	void Watchdog::Run(void* arg) {
83		18	Watchdog* wd = static_cast<Watchdog*>(arg);
84
85			// UV_RUN_DEFAULT the loop will be stopped either by the async or the
86			// timer handle.
87		18	uv_run(&wd->loop_, UV_RUN_DEFAULT);
88
89			// Loop ref count reaches zero when both handles are closed.
90			// Close the timer handle on this side and let ~Watchdog() close async_
91		18	uv_close(reinterpret_cast<uv_handle_t*>(&wd->timer_), nullptr);
92		18	}
93
94		13	void Watchdog::Timer(uv_timer_t* timer) {
95		13	Watchdog* w = ContainerOf(&Watchdog::timer_, timer);
96		13	*w->timed_out_ = true;
97		13	w->isolate()->TerminateExecution();
98		13	uv_stop(&w->loop_);
99		13	}
100
101
102		192	SigintWatchdog::SigintWatchdog(
103		192	v8::Isolate* isolate, bool* received_signal)
104		192	: isolate_(isolate), received_signal_(received_signal) {
105			// Register this watchdog with the global SIGINT/Ctrl+C listener.
106		192	SigintWatchdogHelper::GetInstance()->Register(this);
107			// Start the helper thread, if that has not already happened.
108		192	SigintWatchdogHelper::GetInstance()->Start();
109		192	}
110
111
112		378	SigintWatchdog::~SigintWatchdog() {
113		378	SigintWatchdogHelper::GetInstance()->Unregister(this);
114		378	SigintWatchdogHelper::GetInstance()->Stop();
115			}
116
117		11	SignalPropagation SigintWatchdog::HandleSigint() {
118		11	*received_signal_ = true;
119		11	isolate_->TerminateExecution();
120		11	return SignalPropagation::kStopPropagation;
121			}
122
123		2	void TraceSigintWatchdog::Init(Environment* env, Local<Object> target) {
124		2	Local<FunctionTemplate> constructor = env->NewFunctionTemplate(New);
125		4	constructor->InstanceTemplate()->SetInternalFieldCount(
126			TraceSigintWatchdog::kInternalFieldCount);
127		2	constructor->Inherit(HandleWrap::GetConstructorTemplate(env));
128
129		2	env->SetProtoMethod(constructor, "start", Start);
130		2	env->SetProtoMethod(constructor, "stop", Stop);
131
132		2	env->SetConstructorFunction(target, "TraceSigintWatchdog", constructor);
133		2	}
134
135		1	void TraceSigintWatchdog::New(const FunctionCallbackInfo<Value>& args) {
136			// This constructor should not be exposed to public javascript.
137			// Therefore we assert that we are not trying to call this as a
138			// normal function.
139	✗✓	1	CHECK(args.IsConstructCall());
140		1	Environment* env = Environment::GetCurrent(args);
141		1	new TraceSigintWatchdog(env, args.This());
142		1	}
143
144		2	void TraceSigintWatchdog::Start(const FunctionCallbackInfo<Value>& args) {
145			TraceSigintWatchdog* watchdog;
146	✗✓	2	ASSIGN_OR_RETURN_UNWRAP(&watchdog, args.Holder());
147			// Register this watchdog with the global SIGINT/Ctrl+C listener.
148	✓✗	2	SigintWatchdogHelper::GetInstance()->Register(watchdog);
149			// Start the helper thread, if that has not already happened.
150		2	int r = SigintWatchdogHelper::GetInstance()->Start();
151	✗✓	2	CHECK_EQ(r, 0);
152			}
153
154		2	void TraceSigintWatchdog::Stop(const FunctionCallbackInfo<Value>& args) {
155			TraceSigintWatchdog* watchdog;
156	✗✓	2	ASSIGN_OR_RETURN_UNWRAP(&watchdog, args.Holder());
157	✓✗	2	SigintWatchdogHelper::GetInstance()->Unregister(watchdog);
158		2	SigintWatchdogHelper::GetInstance()->Stop();
159			}
160
161		1	TraceSigintWatchdog::TraceSigintWatchdog(Environment* env, Local<Object> object)
162			: HandleWrap(env,
163			object,
164		1	reinterpret_cast<uv_handle_t*>(&handle_),
165		1	AsyncWrap::PROVIDER_SIGINTWATCHDOG) {
166		1	int r = uv_async_init(env->event_loop(), &handle_, [](uv_async_t* handle) {
167			TraceSigintWatchdog* watchdog =
168			ContainerOf(&TraceSigintWatchdog::handle_, handle);
169			watchdog->signal_flag_ = SignalFlags::FromIdle;
170			watchdog->HandleInterrupt();
171		1	});
172	✗✓	1	CHECK_EQ(r, 0);
173		1	uv_unref(reinterpret_cast<uv_handle_t*>(&handle_));
174		1	}
175
176			SignalPropagation TraceSigintWatchdog::HandleSigint() {
177			/**
178			* In case of uv loop polling, i.e. no JS currently running, activate the
179			* loop to run a piece of JS code to trigger interruption.
180			*/
181			CHECK_EQ(uv_async_send(&handle_), 0);
182			env()->isolate()->RequestInterrupt(
183			[](v8::Isolate* isolate, void* data) {
184			TraceSigintWatchdog* self = static_cast<TraceSigintWatchdog*>(data);
185			if (self->signal_flag_ == SignalFlags::None) {
186			self->signal_flag_ = SignalFlags::FromInterrupt;
187			}
188			self->HandleInterrupt();
189			},
190			this);
191			return SignalPropagation::kContinuePropagation;
192			}
193
194			void TraceSigintWatchdog::HandleInterrupt() {
195			// Do not nest interrupts.
196			if (interrupting) {
197			return;
198			}
199			interrupting = true;
200			if (signal_flag_ == SignalFlags::None) {
201			return;
202			}
203			Environment* env_ = env();
204			// FIXME: Before
205			// https://github.com/nodejs/node/pull/29207#issuecomment-527667993 get
206			// fixed, additional JavaScript code evaluation shall be prevented from
207			// running during interruption.
208			FPrintF(stderr,
209			"KEYBOARD_INTERRUPT: Script execution was interrupted by `SIGINT`\n");
210			if (signal_flag_ == SignalFlags::FromInterrupt) {
211			PrintStackTrace(env_->isolate(),
212			v8::StackTrace::CurrentStackTrace(
213			env_->isolate(), 10, v8::StackTrace::kDetailed));
214			}
215			signal_flag_ = SignalFlags::None;
216			interrupting = false;
217
218			SigintWatchdogHelper::GetInstance()->Unregister(this);
219			SigintWatchdogHelper::GetInstance()->Stop();
220			raise(SIGINT);
221			}
222
223			#ifdef __POSIX__
224		212	void* SigintWatchdogHelper::RunSigintWatchdog(void* arg) {
225			// Inside the helper thread.
226			bool is_stopping;
227
228		14	do {
229		212	uv_sem_wait(&instance.sem_);
230		212	is_stopping = InformWatchdogsAboutSignal();
231	✓✓	212	} while (!is_stopping);
232
233		198	return nullptr;
234			}
235
236		14	void SigintWatchdogHelper::HandleSignal(int signum,
237			siginfo_t* info,
238			void* ucontext) {
239		14	uv_sem_post(&instance.sem_);
240		14	}
241
242			#else
243
244			// Windows starts a separate thread for executing the handler, so no extra
245			// helper thread is required.
246			BOOL WINAPI SigintWatchdogHelper::WinCtrlCHandlerRoutine(DWORD dwCtrlType) {
247			if (!instance.watchdog_disabled_ &&
248			(dwCtrlType == CTRL_C_EVENT \|\| dwCtrlType == CTRL_BREAK_EVENT)) {
249			InformWatchdogsAboutSignal();
250
251			// Return true because the signal has been handled.
252			return TRUE;
253			} else {
254			return FALSE;
255			}
256			}
257			#endif
258
259
260		212	bool SigintWatchdogHelper::InformWatchdogsAboutSignal() {
261		212	Mutex::ScopedLock list_lock(instance.list_mutex_);
262
263		212	bool is_stopping = false;
264			#ifdef __POSIX__
265		212	is_stopping = instance.stopping_;
266			#endif
267
268			// If there are no listeners and the helper thread has been awoken by a signal
269			// (= not when stopping it), indicate that by setting has_pending_signal_.
270	✓✓✓✓ ✓✓	212	if (instance.watchdogs_.empty() && !is_stopping) {
271		3	instance.has_pending_signal_ = true;
272			}
273
274	✓✓	212	for (auto it = instance.watchdogs_.rbegin(); it != instance.watchdogs_.rend();
275			it++) {
276		11	SignalPropagation wp = (*it)->HandleSigint();
277	✓✗	11	if (wp == SignalPropagation::kStopPropagation) {
278		11	break;
279			}
280			}
281
282		212	return is_stopping;
283			}
284
285
286		383	int SigintWatchdogHelper::Start() {
287		766	Mutex::ScopedLock lock(mutex_);
288
289	✓✓	383	if (start_stop_count_++ > 0) {
290		185	return 0;
291			}
292
293			#ifdef __POSIX__
294	✗✓	198	CHECK_EQ(has_running_thread_, false);
295		198	has_pending_signal_ = false;
296		198	stopping_ = false;
297
298			sigset_t sigmask;
299		198	sigfillset(&sigmask);
300			sigset_t savemask;
301	✗✓	198	CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, &savemask));
302		198	sigmask = savemask;
303		198	int ret = pthread_create(&thread_, nullptr, RunSigintWatchdog, nullptr);
304	✗✓	198	CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
305	✗✓	198	if (ret != 0) {
306			return ret;
307			}
308		198	has_running_thread_ = true;
309
310		198	RegisterSignalHandler(SIGINT, HandleSignal);
311			#else
312			if (watchdog_disabled_) {
313			watchdog_disabled_ = false;
314			} else {
315			SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, TRUE);
316			}
317			#endif
318
319		198	return 0;
320			}
321
322
323		5632	bool SigintWatchdogHelper::Stop() {
324			bool had_pending_signal;
325		11264	Mutex::ScopedLock lock(mutex_);
326
327			{
328		5632	Mutex::ScopedLock list_lock(list_mutex_);
329
330		5632	had_pending_signal = has_pending_signal_;
331
332	✓✓	5632	if (--start_stop_count_ > 0) {
333		182	has_pending_signal_ = false;
334		182	return had_pending_signal;
335			}
336
337			#ifdef __POSIX__
338			// Set stopping now because it's only protected by list_mutex_.
339		5450	stopping_ = true;
340			#endif
341
342		5450	watchdogs_.clear();
343			}
344
345			#ifdef __POSIX__
346	✓✓	5450	if (!has_running_thread_) {
347		5252	has_pending_signal_ = false;
348		5252	return had_pending_signal;
349			}
350
351			// Wake up the helper thread.
352		198	uv_sem_post(&sem_);
353
354			// Wait for the helper thread to finish.
355	✗✓	198	CHECK_EQ(0, pthread_join(thread_, nullptr));
356		198	has_running_thread_ = false;
357
358		198	RegisterSignalHandler(SIGINT, SignalExit, true);
359			#else
360			watchdog_disabled_ = true;
361			#endif
362
363		198	had_pending_signal = has_pending_signal_;
364		198	has_pending_signal_ = false;
365
366		198	return had_pending_signal;
367			}
368
369
370		3	bool SigintWatchdogHelper::HasPendingSignal() {
371		3	Mutex::ScopedLock lock(list_mutex_);
372
373		3	return has_pending_signal_;
374			}
375
376		194	void SigintWatchdogHelper::Register(SigintWatchdogBase* wd) {
377		388	Mutex::ScopedLock lock(list_mutex_);
378
379		194	watchdogs_.push_back(wd);
380		194	}
381
382		191	void SigintWatchdogHelper::Unregister(SigintWatchdogBase* wd) {
383		191	Mutex::ScopedLock lock(list_mutex_);
384
385		191	auto it = std::find(watchdogs_.begin(), watchdogs_.end(), wd);
386
387	✗✓	191	CHECK_NE(it, watchdogs_.end());
388		191	watchdogs_.erase(it);
389		191	}
390
391
392		5255	SigintWatchdogHelper::SigintWatchdogHelper()
393			: start_stop_count_(0),
394		5255	has_pending_signal_(false) {
395			#ifdef __POSIX__
396		5255	has_running_thread_ = false;
397		5255	stopping_ = false;
398	✗✓	5255	CHECK_EQ(0, uv_sem_init(&sem_, 0));
399			#else
400			watchdog_disabled_ = false;
401			#endif
402		5255	}
403
404
405		5255	SigintWatchdogHelper::~SigintWatchdogHelper() {
406		5255	start_stop_count_ = 0;
407		5255	Stop();
408
409			#ifdef __POSIX__
410	✗✓	5255	CHECK_EQ(has_running_thread_, false);
411		5255	uv_sem_destroy(&sem_);
412			#endif
413		5255	}
414
415			SigintWatchdogHelper SigintWatchdogHelper::instance;
416
417			namespace watchdog {
418		2	static void Initialize(Local<Object> target,
419			Local<Value> unused,
420			Local<Context> context,
421			void* priv) {
422		2	Environment* env = Environment::GetCurrent(context);
423		2	TraceSigintWatchdog::Init(env, target);
424		2	}
425			} // namespace watchdog
426
427			} // namespace node
428
429		5255	NODE_MODULE_CONTEXT_AWARE_INTERNAL(watchdog, node::watchdog::Initialize)