1 /* Asynchronous timers.
2 Copyright (C) 2000-2023 Free Software Foundation, Inc.
3
4 This file is part of GNU Emacs.
5
6 GNU Emacs 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 (at
9 your option) any later version.
10
11 GNU Emacs 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 GNU Emacs. If not, see <https://www.gnu.org/licenses/>. */
18
19 #ifndef EMACS_ATIMER_H
20 #define EMACS_ATIMER_H
21
22 #include <time.h>
23
24 /* Forward declaration. */
25
26 struct atimer;
27
28 /* Types of timers. */
29
30 enum atimer_type
31 {
32 /* Timer is ripe at some absolute time. */
33 ATIMER_ABSOLUTE,
34
35 /* Timer is ripe at now plus an offset. */
36 ATIMER_RELATIVE,
37
38 /* Timer runs continuously. */
39 ATIMER_CONTINUOUS
40 };
41
42 /* Type of timer callback functions. */
43
44 typedef void (* atimer_callback) (struct atimer *timer);
45
46 /* Structure describing an asynchronous timer. */
47
48 struct atimer
49 {
50 /* The type of this timer. */
51 enum atimer_type type;
52
53 /* Time when this timer is ripe. */
54 struct timespec expiration;
55
56 /* Interval of this timer. */
57 struct timespec interval;
58
59 /* Function to call when timer is ripe. Interrupt input is
60 guaranteed to not be blocked when this function is called. */
61 atimer_callback fn;
62
63 /* Additional user-specified data to pass to FN. */
64 void *client_data;
65
66 /* Next in list of active or free atimers. */
67 struct atimer *next;
68 };
69
70 /* Function prototypes. */
71
72 struct atimer *start_atimer (enum atimer_type, struct timespec,
73 atimer_callback, void *);
74 void cancel_atimer (struct atimer *);
75 void do_pending_atimers (void);
76 void init_atimer (void);
77 void turn_on_atimers (bool);
78 void stop_other_atimers (struct atimer *);
79 void run_all_atimers (void);
80 #ifdef HAVE_TIMERFD
81 void timerfd_callback (int, void *);
82 #endif
83
84 #endif /* EMACS_ATIMER_H */