Ejemplo n.º 1
0
void
start_event_loop (void)
{
    /* Loop until there is nothing to do.  This is the entry point to
       the event loop engine.  gdb_do_one_event will process one event
       for each invocation.  It blocks waiting for an event and then
       processes it.  */
    while (1)
    {
        int result = 0;

        TRY
        {
            result = gdb_do_one_event ();
        }
        CATCH (ex, RETURN_MASK_ALL)
        {
            exception_print (gdb_stderr, ex);

            /* If any exception escaped to here, we better enable
               stdin.  Otherwise, any command that calls async_disable_stdin,
               and then throws, will leave stdin inoperable.  */
            async_enable_stdin ();
            /* If we long-jumped out of do_one_event, we probably didn't
               get around to resetting the prompt, which leaves readline
               in a messed-up state.  Reset it here.  */
            current_ui->prompt_state = PROMPT_NEEDED;
            observer_notify_command_error ();
            /* This call looks bizarre, but it is required.  If the user
               entered a command that caused an error,
               after_char_processing_hook won't be called from
               rl_callback_read_char_wrapper.  Using a cleanup there
               won't work, since we want this function to be called
               after a new prompt is printed.  */
            if (after_char_processing_hook)
                (*after_char_processing_hook) ();
            /* Maybe better to set a flag to be checked somewhere as to
               whether display the prompt or not.  */
        }
        END_CATCH

        if (result < 0)
            break;
    }
Ejemplo n.º 2
0
/* General function to handle events in the inferior.  So far it just
   takes care of detecting errors reported by select() or poll(),
   otherwise it assumes that all is OK, and goes on reading data from
   the fd.  This however may not always be what we want to do.  */
void
inferior_event_handler (enum inferior_event_type event_type, 
			gdb_client_data client_data)
{
  struct cleanup *cleanup_if_error = make_bpstat_clear_actions_cleanup ();

  switch (event_type)
    {
    case INF_REG_EVENT:
      /* Use catch errors for now, until the inner layers of
	 fetch_inferior_event (i.e. readchar) can return meaningful
	 error status.  If an error occurs while getting an event from
	 the target, just cancel the current command.  */
      if (!catch_errors (fetch_inferior_event_wrapper, 
			 client_data, "", RETURN_MASK_ALL))
	{
	  bpstat_clear_actions ();
	  do_all_intermediate_continuations (1);
	  do_all_continuations (1);
	  async_enable_stdin ();
	  observer_notify_command_error ();
	}
      break;

    case INF_EXEC_COMPLETE:
      if (!non_stop)
	{
	  /* Unregister the inferior from the event loop.  This is done
	     so that when the inferior is not running we don't get
	     distracted by spurious inferior output.  */
	  if (target_has_execution)
	    target_async (NULL, 0);
	}

      /* Do all continuations associated with the whole inferior (not
	 a particular thread).  */
      if (!ptid_equal (inferior_ptid, null_ptid))
	do_all_inferior_continuations (0);

      /* If we were doing a multi-step (eg: step n, next n), but it
	 got interrupted by a breakpoint, still do the pending
	 continuations.  The continuation itself is responsible for
	 distinguishing the cases.  The continuations are allowed to
	 touch the inferior memory, e.g. to remove breakpoints, so run
	 them before running breakpoint commands, which may resume the
	 target.  */
      if (non_stop
	  && target_has_execution
	  && !ptid_equal (inferior_ptid, null_ptid))
	do_all_intermediate_continuations_thread (inferior_thread (), 0);
      else
	do_all_intermediate_continuations (0);

      /* Always finish the previous command before running any
	 breakpoint commands.  Any stop cancels the previous command.
	 E.g. a "finish" or "step-n" command interrupted by an
	 unrelated breakpoint is canceled.  */
      if (non_stop
	  && target_has_execution
	  && !ptid_equal (inferior_ptid, null_ptid))
	do_all_continuations_thread (inferior_thread (), 0);
      else
	do_all_continuations (0);

      /* When running a command list (from a user command, say), these
	 are only run when the command list is all done.  */
      if (interpreter_async)
	{
	  volatile struct gdb_exception e;

	  check_frame_language_change ();

	  /* Don't propagate breakpoint commands errors.  Either we're
	     stopping or some command resumes the inferior.  The user will
	     be informed.  */
	  TRY_CATCH (e, RETURN_MASK_ALL)
	    {
	      bpstat_do_actions ();
	    }
	  exception_print (gdb_stderr, e);
	}
      break;

    case INF_EXEC_CONTINUE:
      /* Is there anything left to do for the command issued to
         complete?  */

      if (non_stop)
	do_all_intermediate_continuations_thread (inferior_thread (), 0);
      else
	do_all_intermediate_continuations (0);
      break;

    case INF_TIMER:
    default:
      printf_unfiltered (_("Event type not recognized.\n"));
      break;
    }

  discard_cleanups (cleanup_if_error);
}