gearman/util/signal.hpp

/*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
 *
 *  Data Differential Utility library
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#pragma once 

#include <pthread.h>
#include <semaphore.h>
#include <random>

#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif

#ifdef	__cplusplus
extern "C" {
#endif

typedef void (signal_callback_fn)();

#ifdef	__cplusplus
}
#endif

namespace datadifferential {
namespace util {

enum shutdown_t {
  SHUTDOWN_RUNNING,
  SHUTDOWN_GRACEFUL,
  SHUTDOWN_FORCED
};

class SignalThread {
  bool _exit_on_signal;
  sigset_t set;
  sem_t *lock;
  uint64_t magic_memory;
  volatile shutdown_t __shutdown;
  pthread_mutex_t shutdown_mutex;

  std::string random_lock_name(std::string::size_type);

public:

  SignalThread(bool exit_on_signal_arg= false);

  void test();
  void post();
  bool setup();

  bool exit_on_signal()
  {
    return _exit_on_signal;
  }

  int wait(int& sig)
  {
    return sigwait(&set, &sig);
  }

  ~SignalThread();

  void set_shutdown(shutdown_t arg);
  bool is_shutdown();
  shutdown_t get_shutdown();

  void sighup();
  void sighup(signal_callback_fn* arg);

private:
  pthread_t thread;
  signal_callback_fn* _sighup;
};

} /* namespace util */
} /* namespace datadifferential */