quit.hh

/* quit.h -- How to handle SIGINT gracefully. */

/* Copyright (C) 1993-2013 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   Bash is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with Bash.  If not, see <http://www.gnu.org/licenses/>.
*/

#if !defined(_QUIT_H_)
#define _QUIT_H_

#include "sig.hh" /* for sig_atomic_t */

namespace bash
{

/* Non-zero means SIGINT has already occurred. */
extern volatile sig_atomic_t interrupt_state;

extern volatile sig_atomic_t terminating_signal;

/* Macro to call a great deal.  SIGINT just sets the interrupt_state variable.
   When it is safe, put QUIT in the code, and the "interrupt" will take
   place.  The same scheme is used for terminating signals (e.g., SIGHUP)
   and the terminating_signal variable.  That calls a function which will
   end up exiting the shell. */
#define QUIT                                                                  \
  do                                                                          \
    {                                                                         \
      if (terminating_signal)                                                 \
        termsig_handler (terminating_signal);                                 \
      if (interrupt_state)                                                    \
        throw_to_top_level ();                                                \
    }                                                                         \
  while (0)

#define CHECK_ALRM                                                            \
  do                                                                          \
    {                                                                         \
      if (sigalrm_seen)                                                       \
        throw sigalarm_interrupt ();                                          \
    }                                                                         \
  while (0)

#define SETINTERRUPT interrupt_state = 1
#define CLRINTERRUPT interrupt_state = 0

// Note: increment and decrement on volatile types is deprecated.
#define ADDINTERRUPT interrupt_state = interrupt_state + 1
#define DELINTERRUPT interrupt_state = interrupt_state - 1

#define ISINTERRUPT interrupt_state != 0

/* The same sort of thing, this time just for signals that would ordinarily
   cause the shell to terminate. */

#define CHECK_TERMSIG                                                         \
  do                                                                          \
    {                                                                         \
      if (terminating_signal)                                                 \
        termsig_handler (terminating_signal);                                 \
    }                                                                         \
  while (0)

#define LASTSIG()                                                             \
  (terminating_signal ? terminating_signal : (interrupt_state ? SIGINT : 0))

#define CHECK_WAIT_INTR                                                       \
  do                                                                          \
    {                                                                         \
      if (wait_intr_flag && wait_signal_received && this_shell_builtin        \
          && (this_shell_builtin == wait_builtin))                            \
        throw wait_interrupt ();                                              \
    }                                                                         \
  while (0)

#define RESET_SIGTERM                                                         \
  do                                                                          \
    {                                                                         \
      sigterm_received = 0;                                                   \
    }                                                                         \
  while (0)

#define CHECK_SIGTERM                                                         \
  do                                                                          \
    {                                                                         \
      if (sigterm_received)                                                   \
        termsig_handler (SIGTERM);                                            \
    }                                                                         \
  while (0)

} // namespace bash

#endif /* _QUIT_H_ */