// 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.

#ifndef SRC_NODE_WATCHDOG_H_

#define SRC_NODE_WATCHDOG_H_

#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#include <vector>

#include "handle_wrap.h"

#include "memory_tracker-inl.h"

#include "node_mutex.h"

#include "uv.h"

#include "v8.h"

#ifdef __POSIX__

#include <pthread.h>

#endif

namespace node {

enum class SignalPropagation {

  kContinuePropagation,

  kStopPropagation,

};

class Watchdog {

 public:

  explicit Watchdog(v8::Isolate* isolate,

                    uint64_t ms,

                    bool* timed_out = nullptr);

  ~Watchdog();

  v8::Isolate* isolate() { return isolate_; }

 private:

  static void Run(void* arg);

  static void Timer(uv_timer_t* timer);

  v8::Isolate* isolate_;

  uv_thread_t thread_;

  uv_loop_t loop_;

  uv_async_t async_;

  uv_timer_t timer_;

  bool* timed_out_;

};

class SigintWatchdogBase {

 public:

  virtual ~SigintWatchdogBase() = default;

  virtual SignalPropagation HandleSigint() = 0;

};

class SigintWatchdog : public SigintWatchdogBase {

 public:

  explicit SigintWatchdog(v8::Isolate* isolate,

                          bool* received_signal = nullptr);

  ~SigintWatchdog();

  v8::Isolate* isolate() { return isolate_; }

  SignalPropagation HandleSigint() override;

 private:

  v8::Isolate* isolate_;

  bool* received_signal_;

};

class TraceSigintWatchdog : public HandleWrap, public SigintWatchdogBase {

 public:

  static void Init(Environment* env, v8::Local<v8::Object> target);

  static void New(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Start(const v8::FunctionCallbackInfo<v8::Value>& args);

  static void Stop(const v8::FunctionCallbackInfo<v8::Value>& args);

  SignalPropagation HandleSigint() override;

  inline void MemoryInfo(node::MemoryTracker* tracker) const override {

    tracker->TrackInlineField("handle_", handle_);

  }

  SET_MEMORY_INFO_NAME(TraceSigintWatchdog)

  SET_SELF_SIZE(TraceSigintWatchdog)

 private:

  enum class SignalFlags { None, FromIdle, FromInterrupt };

  TraceSigintWatchdog(Environment* env, v8::Local<v8::Object> object);

  void HandleInterrupt();

  bool interrupting = false;

  uv_async_t handle_;

  SignalFlags signal_flag_ = SignalFlags::None;

};

class SigintWatchdogHelper {

 public:

  static SigintWatchdogHelper* GetInstance() { return &instance; }

  static Mutex& GetInstanceActionMutex() { return instance_action_mutex_; }

  void Register(SigintWatchdogBase* watchdog);

  void Unregister(SigintWatchdogBase* watchdog);

  bool HasPendingSignal();

  int Start();

  bool Stop();

 private:

  SigintWatchdogHelper();

  ~SigintWatchdogHelper();

  static bool InformWatchdogsAboutSignal();

  static SigintWatchdogHelper instance;

  static Mutex instance_action_mutex_;

  int start_stop_count_;

  Mutex mutex_;

  Mutex list_mutex_;

  std::vector<SigintWatchdogBase*> watchdogs_;

  bool has_pending_signal_;

#ifdef __POSIX__

  pthread_t thread_;

  uv_sem_t sem_;

  bool has_running_thread_;

  bool stopping_;

  static void* RunSigintWatchdog(void* arg);

  static void HandleSignal(int signum, siginfo_t* info, void* ucontext);

#else

  bool watchdog_disabled_;

  static BOOL WINAPI WinCtrlCHandlerRoutine(DWORD dwCtrlType);

#endif

};

}  // namespace node

#endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS

#endif  // SRC_NODE_WATCHDOG_H_