signals_posix.hpp

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#ifndef OS_POSIX_SIGNALS_POSIX_HPP
#define OS_POSIX_SIGNALS_POSIX_HPP

#include "memory/allocation.hpp"
#include "utilities/globalDefinitions.hpp"

class outputStream;
class Thread;
class OSThread;

class PosixSignals : public AllStatic {

public:

  // Signal number used to suspend/resume a thread
  static int SR_signum;

  static int init();
  // The platform dependent parts of the central hotspot signal handler.
  // Returns true if the signal had been recognized and handled, false if not. If true, caller should
  // return from signal handling.
  static bool pd_hotspot_signal_handler(int sig, siginfo_t* info, ucontext_t* uc, JavaThread* thread);

  static bool is_sig_ignored(int sig);

  static void hotspot_sigmask(Thread* thread);

  static void print_signal_handler(outputStream* st, int sig, char* buf, size_t buflen);

  // Suspend-resume
  static bool do_suspend(OSThread* osthread);
  static void do_resume(OSThread* osthread);

  // For signal-chaining
  static bool chained_handler(int sig, siginfo_t* siginfo, void* context);

  // Unblock all signals whose delivery cannot be deferred and which, if they happen
  //  while delivery is blocked, would cause crashes or hangs (see JDK-8252533).
  static void unblock_error_signals();
};

#endif // OS_POSIX_SIGNALS_POSIX_HPP