blob: 4333f8f810e990f687d6a2f489012e364ed10208 [file] [log] [blame]
/* Serial interface for a selectable event.
Copyright (C) 2016-2021 Free Software Foundation, Inc.
This file is part of GDB.
This program 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.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef SER_EVENT_H
#define SER_EVENT_H
/* This is used to be able to signal the event loop (or any other
select/poll) of events, in a race-free manner.
For example, a signal handler can defer non-async-signal-safe work
to the event loop, by having the signal handler set a struct
serial_event object, and having the event loop wait for that same
object to the readable. Once readable, the event loop breaks out
of select/poll and calls a registered callback that does the
deferred work. */
struct serial_event;
/* Make a new serial_event object. */
struct serial_event *make_serial_event (void);
/* Return the FD that can be used by select/poll to wait for the
event. The only valid operation on this object is to wait until it
is readable. */
extern int serial_event_fd (struct serial_event *event);
/* Set the event. This signals the file descriptor returned by
serial_event_fd as readable. */
extern void serial_event_set (struct serial_event *event);
/* Clear the event. The file descriptor returned by serial_event_fd
is not longer readable after this, until a new serial_event_set
call is made. */
extern void serial_event_clear (struct serial_event *event);
#endif