| 1 | /* Serial interface for a selectable event. |
| 2 | Copyright (C) 2016-2018 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 3 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #ifndef SER_EVENT_H |
| 20 | #define SER_EVENT_H |
| 21 | |
| 22 | /* This is used to be able to signal the event loop (or any other |
| 23 | select/poll) of events, in a race-free manner. |
| 24 | |
| 25 | For example, a signal handler can defer non-async-signal-safe work |
| 26 | to the event loop, by having the signal handler set a struct |
| 27 | serial_event object, and having the event loop wait for that same |
| 28 | object to the readable. Once readable, the event loop breaks out |
| 29 | of select/poll and calls a registered callback that does the |
| 30 | deferred work. */ |
| 31 | |
| 32 | struct serial_event; |
| 33 | |
| 34 | /* Make a new serial_event object. */ |
| 35 | struct serial_event *make_serial_event (void); |
| 36 | |
| 37 | /* Return the FD that can be used by select/poll to wait for the |
| 38 | event. The only valid operation on this object is to wait until it |
| 39 | is readable. */ |
| 40 | extern int serial_event_fd (struct serial_event *event); |
| 41 | |
| 42 | /* Set the event. This signals the file descriptor returned by |
| 43 | serial_event_fd as readable. */ |
| 44 | extern void serial_event_set (struct serial_event *event); |
| 45 | |
| 46 | /* Clear the event. The file descriptor returned by serial_event_fd |
| 47 | is not longer readable after this, until a new serial_event_set |
| 48 | call is made. */ |
| 49 | extern void serial_event_clear (struct serial_event *event); |
| 50 | |
| 51 | #endif |