trap.c

android-w.song.android.widget

	retval = trap_saved_exit_value;

      running_trap = 0;
      return retval;
    }

#if defined (ARRAY_VARS)
  restore_pipestatus_array (ps);
#endif
  return (trap_saved_exit_value);
}

void
run_trap_cleanup (sig)
     int sig;
{
  sigmodes[sig] &= ~(SIG_INPROGRESS|SIG_CHANGED);
}

/* Run a trap command for SIG.  SIG is one of the signals the shell treats
   specially.  Returns the exit status of the executed trap command list. */
static int
_run_trap_internal (sig, tag)
     int sig;
     char *tag;
{
  char *trap_command, *old_trap;
  int trap_exit_value, *token_state;
  int save_return_catch_flag, function_code, flags;
  procenv_t save_return_catch;
  WORD_LIST *save_subst_varlist;
#if defined (ARRAY_VARS)
  ARRAY *ps;
#endif

  trap_exit_value = function_code = 0;
  /* Run the trap only if SIG is trapped and not ignored, and we are not
     currently executing in the trap handler. */
  if ((sigmodes[sig] & SIG_TRAPPED) && ((sigmodes[sig] & SIG_IGNORED) == 0) &&
      (trap_list[sig] != (char *)IMPOSSIBLE_TRAP_HANDLER) &&
      ((sigmodes[sig] & SIG_INPROGRESS) == 0))
    {
      old_trap = trap_list[sig];
      sigmodes[sig] |= SIG_INPROGRESS;
      sigmodes[sig] &= ~SIG_CHANGED;		/* just to be sure */
      trap_command =  savestring (old_trap);

      running_trap = sig + 1;
      trap_saved_exit_value = last_command_exit_value;
#if defined (ARRAY_VARS)
      ps = save_pipestatus_array ();
#endif

      token_state = save_token_state ();
      save_subst_varlist = subst_assign_varlist;
      subst_assign_varlist = 0;

      /* If we're in a function, make sure return longjmps come here, too. */
      save_return_catch_flag = return_catch_flag;
      if (return_catch_flag)
	{
	  COPY_PROCENV (return_catch, save_return_catch);
	  function_code = setjmp (return_catch);
	}

      flags = SEVAL_NONINT|SEVAL_NOHIST;
      if (sig != DEBUG_TRAP && sig != RETURN_TRAP && sig != ERROR_TRAP)
	flags |= SEVAL_RESETLINE;
      if (function_code == 0)
	parse_and_execute (trap_command, tag, flags);

      restore_token_state (token_state);
      free (token_state);

      subst_assign_varlist = save_subst_varlist;

      trap_exit_value = last_command_exit_value;
      last_command_exit_value = trap_saved_exit_value;
#if defined (ARRAY_VARS)
      restore_pipestatus_array (ps);
#endif
      running_trap = 0;

      sigmodes[sig] &= ~SIG_INPROGRESS;

      if (sigmodes[sig] & SIG_CHANGED)
	{
#if 0
	  /* Special traps like EXIT, DEBUG, RETURN are handled explicitly in
	     the places where they can be changed using unwind-protects.  For
	     example, look at execute_cmd.c:execute_function(). */
	  if (SPECIAL_TRAP (sig) == 0)
#endif
	    free (old_trap);
	  sigmodes[sig] &= ~SIG_CHANGED;
	}

      if (save_return_catch_flag)
	{
	  return_catch_flag = save_return_catch_flag;
	  return_catch_value = trap_exit_value;
	  COPY_PROCENV (save_return_catch, return_catch);
	  if (function_code)
	    longjmp (return_catch, 1);
	}
    }

  return trap_exit_value;
}

int
run_debug_trap ()
{
  int trap_exit_value;
  pid_t save_pgrp;
  int save_pipe[2];

  /* XXX - question:  should the DEBUG trap inherit the RETURN trap? */
  trap_exit_value = 0;
  if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && ((sigmodes[DEBUG_TRAP] & SIG_IGNORED) == 0) && ((sigmodes[DEBUG_TRAP] & SIG_INPROGRESS) == 0))
    {
#if defined (JOB_CONTROL)
      save_pgrp = pipeline_pgrp;
      pipeline_pgrp = 0;
      save_pipeline (1);
#  if defined (PGRP_PIPE)
      save_pgrp_pipe (save_pipe, 1);
#  endif
      stop_making_children ();
#endif

      trap_exit_value = _run_trap_internal (DEBUG_TRAP, "debug trap");

#if defined (JOB_CONTROL)
      pipeline_pgrp = save_pgrp;
      restore_pipeline (1);
#  if defined (PGRP_PIPE)
      close_pgrp_pipe ();
      restore_pgrp_pipe (save_pipe);
#  endif
      if (pipeline_pgrp > 0)
	give_terminal_to (pipeline_pgrp, 1);
      notify_and_cleanup ();
#endif
      
#if defined (DEBUGGER)
      /* If we're in the debugger and the DEBUG trap returns 2 while we're in
	 a function or sourced script, we force a `return'. */
      if (debugging_mode && trap_exit_value == 2 && return_catch_flag)
	{
	  return_catch_value = trap_exit_value;
	  longjmp (return_catch, 1);
	}
#endif
    }
  return trap_exit_value;
}

void
run_error_trap ()
{
  if ((sigmodes[ERROR_TRAP] & SIG_TRAPPED) && ((sigmodes[ERROR_TRAP] & SIG_IGNORED) == 0) && (sigmodes[ERROR_TRAP] & SIG_INPROGRESS) == 0)
    _run_trap_internal (ERROR_TRAP, "error trap");
}

void
run_return_trap ()
{
  int old_exit_value;

#if 0
  if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && (sigmodes[DEBUG_TRAP] & SIG_INPROGRESS))
    return;
#endif

  if ((sigmodes[RETURN_TRAP] & SIG_TRAPPED) && ((sigmodes[RETURN_TRAP] & SIG_IGNORED) == 0) && (sigmodes[RETURN_TRAP] & SIG_INPROGRESS) == 0)
    {
      old_exit_value = last_command_exit_value;
      _run_trap_internal (RETURN_TRAP, "return trap");
      last_command_exit_value = old_exit_value;
    }
}

/* Run a trap set on SIGINT.  This is called from throw_to_top_level (), and
   declared here to localize the trap functions. */
void
run_interrupt_trap ()
{
  _run_trap_internal (SIGINT, "interrupt trap");
}

/* Free all the allocated strings in the list of traps and reset the trap
   values to the default.  Intended to be called from subshells that want
   to complete work done by reset_signal_handlers upon execution of a
   subsequent `trap' command that changes a signal's disposition. */
void
free_trap_strings ()
{
  register int i;

  for (i = 0; i < BASH_NSIG; i++)
    free_trap_string (i);
  trap_list[DEBUG_TRAP] = trap_list[EXIT_TRAP] = trap_list[ERROR_TRAP] = trap_list[RETURN_TRAP] = (char *)NULL;
}

/* Free a trap command string associated with SIG without changing signal
   disposition.  Intended to be called from free_trap_strings()  */
static void
free_trap_string (sig)
     int sig;
{
  change_signal (sig, (char *)DEFAULT_SIG);
  sigmodes[sig] &= ~SIG_TRAPPED;
}

/* Reset the handler for SIG to the original value but leave the trap string
   in place. */
static void
reset_signal (sig)
     int sig;
{
  set_signal_handler (sig, original_signals[sig]);
  sigmodes[sig] &= ~SIG_TRAPPED;
}

/* Set the handler signal SIG to the original and free any trap
   command associated with it. */
static void
restore_signal (sig)
     int sig;
{
  set_signal_handler (sig, original_signals[sig]);
  change_signal (sig, (char *)DEFAULT_SIG);
  sigmodes[sig] &= ~SIG_TRAPPED;
}

static void
reset_or_restore_signal_handlers (reset)
     sh_resetsig_func_t *reset;
{
  register int i;

  /* Take care of the exit trap first */
  if (sigmodes[EXIT_TRAP] & SIG_TRAPPED)
    {
      sigmodes[EXIT_TRAP] &= ~SIG_TRAPPED;
      if (reset != reset_signal)
	{
	  free_trap_command (EXIT_TRAP);
	  trap_list[EXIT_TRAP] = (char *)NULL;
	}
    }

  for (i = 1; i < NSIG; i++)
    {
      if (sigmodes[i] & SIG_TRAPPED)
	{
	  if (trap_list[i] == (char *)IGNORE_SIG)
	    set_signal_handler (i, SIG_IGN);
	  else
	    (*reset) (i);
	}
      else if (sigmodes[i] & SIG_SPECIAL)
	(*reset) (i);
    }

  /* Command substitution and other child processes don't inherit the
     debug, error, or return traps.  If we're in the debugger, and the
     `functrace' or `errtrace' options have been set, then let command
     substitutions inherit them.  Let command substitution inherit the
     RETURN trap if we're in the debugger and tracing functions. */
  if (function_trace_mode == 0)
    {
      sigmodes[DEBUG_TRAP] &= ~SIG_TRAPPED;
      sigmodes[RETURN_TRAP] &= ~SIG_TRAPPED;
    }
  if (error_trace_mode == 0)
    sigmodes[ERROR_TRAP] &= ~SIG_TRAPPED;
}

/* Reset trapped signals to their original values, but don't free the
   trap strings.  Called by the command substitution code and other places
   that create a "subshell environment". */
void
reset_signal_handlers ()
{
  reset_or_restore_signal_handlers (reset_signal);
}

/* Reset all trapped signals to their original values.  Signals set to be
   ignored with trap '' SIGNAL should be ignored, so we make sure that they
   are.  Called by child processes after they are forked. */
void
restore_original_signals ()
{
  reset_or_restore_signal_handlers (restore_signal);
}

/* If a trap handler exists for signal SIG, then call it; otherwise just
   return failure. */
int
maybe_call_trap_handler (sig)
     int sig;
{
  /* Call the trap handler for SIG if the signal is trapped and not ignored. */
  if ((sigmodes[sig] & SIG_TRAPPED) && ((sigmodes[sig] & SIG_IGNORED) == 0))
    {
      switch (sig)
	{
	case SIGINT:
	  run_interrupt_trap ();
	  break;
	case EXIT_TRAP:
	  run_exit_trap ();
	  break;
	case DEBUG_TRAP:
	  run_debug_trap ();
	  break;
	case ERROR_TRAP:
	  run_error_trap ();
	  break;
	default:
	  trap_handler (sig);
	  break;
	}
      return (1);
    }
  else
    return (0);
}

int
signal_is_trapped (sig)
     int sig;
{
  return (sigmodes[sig] & SIG_TRAPPED);
}

int
signal_is_special (sig)
     int sig;
{
  return (sigmodes[sig] & SIG_SPECIAL);
}

int
signal_is_ignored (sig)
     int sig;
{
  return (sigmodes[sig] & SIG_IGNORED);
}

int
signal_is_hard_ignored (sig)
     int sig;
{
  return (sigmodes[sig] & SIG_HARD_IGNORE);
}

void
set_signal_ignored (sig)
     int sig;
{
  sigmodes[sig] |= SIG_HARD_IGNORE;
  original_signals[sig] = SIG_IGN;
}

int
signal_in_progress (sig)
     int sig;
{
  return (sigmodes[sig] & SIG_INPROGRESS);
}