summaryrefslogtreecommitdiff
path: root/ev.h
blob: 6a326066d0cf8c7ce68b37cb022451c8cc4f5472 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
/*
 * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
 *       with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef EV_H
#define EV_H

typedef double ev_tstamp;

/* eventmask, revents, events... */
#define EV_UNDEF   -1 /* guaranteed to be invalid */
#define EV_NONE    0x00
#define EV_READ    0x01
#define EV_WRITE   0x02
#define EV_TIMEOUT 0x04
#define EV_SIGNAL  0x08
#define EV_IDLE    0x10
#define EV_CHECK   0x20
#define EV_PREPARE 0x40
#define EV_CHILD   0x80
#define EV_ERROR   (0xff|0x8000)

/* can be used to add custom fields to all watchers */
#ifndef EV_COMMON
# define EV_COMMON void *data
#endif
#ifndef EV_PROTOTYPES
# define EV_PROTOTYPES 1
#endif

/*
 * struct member types:
 * private: you can look at them, but not change them, and they might not mean anything to you.
 * ro: can be read anytime, but only changed when the watcher isn't active
 * rw: can be read and modified anytime, even when the watcher is active
 */

/* shared by all watchers */
#define EV_WATCHER(type)			\
  int active; /* private */			\
  int pending; /* private */			\
  EV_COMMON; /* rw */				\
  void (*cb)(struct type *, int revents); /* rw */ /* gets invoked with an eventmask */

#define EV_WATCHER_LIST(type)			\
  EV_WATCHER (type);				\
  struct type *next /* private */

#define EV_WATCHER_TIME(type)			\
  EV_WATCHER (type);				\
  ev_tstamp at     /* private */

/* base class, nothing to see here unless you subclass */
struct ev_watcher {
  EV_WATCHER (ev_watcher);
};

/* base class, nothing to see here unless you subclass */
struct ev_watcher_list {
  EV_WATCHER_LIST (ev_watcher_list);
};

/* base class, nothing to see here unless you subclass */
struct ev_watcher_time {
  EV_WATCHER_TIME (ev_watcher_time);
};

/* invoked after a specific time, repeatable (based on monotonic clock) */
struct ev_timer
{
  EV_WATCHER_TIME (ev_timer);

  ev_tstamp repeat; /* rw */
};

/* invoked at some specific time, possibly repeating at regular intervals (based on UTC) */
struct ev_periodic
{
  EV_WATCHER_TIME (ev_periodic);

  ev_tstamp interval; /* rw */
};

/* invoked when fd is either EV_READable or EV_WRITEable */
struct ev_io
{
  EV_WATCHER_LIST (ev_io);

  int fd;     /* ro */
  int events; /* ro */
};

/* invoked when the given signal has been received */
struct ev_signal
{
  EV_WATCHER_LIST (ev_signal);

  int signum; /* ro */
};

/* invoked when the nothing else needs to be done, keeps the process from blocking */
struct ev_idle
{
  EV_WATCHER (ev_idle);
};

/* invoked for each run of the mainloop, just before the blocking call */
/* you can still change events in any way you like */
struct ev_prepare
{
  EV_WATCHER (ev_prepare);
};

/* invoked for each run of the mainloop, just after the blocking call */
struct ev_check
{
  EV_WATCHER (ev_check);
};

/* invoked when sigchld is received and waitpid indicates the givne pid */
struct ev_child
{
  EV_WATCHER_LIST (ev_child);

  int pid;    /* ro */
  int status; /* rw, holds the exit status, use the macros from sys/wait.h */
};

#define EVMETHOD_NONE   0
#define EVMETHOD_SELECT 1
#define EVMETHOD_EPOLL  2
#if EV_PROTOTYPES
extern int ev_method;
int ev_init (int flags); /* returns ev_method */

/* these three calls are suitable for plugging into pthread_atfork */
void ev_prefork (void);
void ev_postfork_parent (void);
void ev_postfork_child (void);

extern ev_tstamp ev_now; /* time w.r.t. timers and the eventloop, updated after each poll */
ev_tstamp ev_time (void);
#endif

#define EVLOOP_NONBLOCK	1 /* do not block/wait */
#define EVLOOP_ONESHOT	2 /* block *once* only */
#if EV_PROTOTYPES
void ev_loop (int flags);
extern int ev_loop_done; /* set to 1 to break out of event loop, set to 2 to break out of all event loops */

/* convinience function, wait for a single event, without registering an event watcher */
/* if timeout is < 0, do wait indefinitely */
void ev_once (int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg);
#endif

/* these may evaluate ev multiple times, and the other arguments at most once */
/* either use evw_init + evXXX_set, or the evXXX_init macro, below, to first initialise a watcher */
#define evw_init(ev,cb_)                   do { (ev)->active = 0; (ev)->pending = 0; (ev)->cb = (cb_); } while (0)

#define evio_set(ev,fd_,events_)           do { (ev)->fd = (fd_); (ev)->events = (events_); } while (0)
#define evtimer_set(ev,after_,repeat_)     do { (ev)->at = (after_); (ev)->repeat = (repeat_); } while (0)
#define evperiodic_set(ev,at_,interval_)   do { (ev)->at = (at_); (ev)->interval = (interval_); } while (0)
#define evsignal_set(ev,signum_)           do { (ev)->signum = (signum_); } while (0)
#define evidle_set(ev)                     /* nop, yes, this is a serious in-joke */
#define evprepare_set(ev)                  /* nop, yes, this is a serious in-joke */
#define evcheck_set(ev)                    /* nop, yes, this is a serious in-joke */
#define evchild_set(ev,pid_)               do { (ev)->pid = (pid_); } while (0)

#define evio_init(ev,cb,fd,events)         do { evw_init ((ev), (cb)); evio_set ((ev),(fd),(events)); } while (0)
#define evtimer_init(ev,cb,after,repeat)   do { evw_init ((ev), (cb)); evtimer_set ((ev),(after),(repeat)); } while (0)
#define evperiodic_init(ev,cb,at,interval) do { evw_init ((ev), (cb)); evperiodic_set ((ev),(at),(interval)); } while (0)
#define evsignal_init(ev,cb,signum)        do { evw_init ((ev), (cb)); evsignal_set ((ev), (signum)); } while (0)
#define evidle_init(ev,cb)                 do { evw_init ((ev), (cb)); evidle_set ((ev)); } while (0)
#define evprepare_init(ev,cb)              do { evw_init ((ev), (cb)); evprepare_set ((ev)); } while (0)
#define evcheck_init(ev,cb)                do { evw_init ((ev), (cb)); evcheck_set ((ev)); } while (0)
#define evchild_init(ev,cb,pid)            do { evw_init ((ev), (cb)); evchild_set ((ev),(pid)); } while (0)

#define ev_is_active(ev) (0 + (ev)->active) /* true when the watcher has been started */

/* stopping (enabling, adding) a watcher does nothing if it is already running */
/* stopping (disabling, deleting) a watcher does nothing unless its already running */
#if EV_PROTOTYPES
void evio_start       (struct ev_io *w);
void evio_stop        (struct ev_io *w);

void evtimer_start    (struct ev_timer *w);
void evtimer_stop     (struct ev_timer *w);
void evtimer_again    (struct ev_timer *w); /* stops if active and no repeat, restarts if active and repeating, starts if inactive and repeating */

void evperiodic_start (struct ev_periodic *w);
void evperiodic_stop  (struct ev_periodic *w);

void evsignal_start   (struct ev_signal *w);
void evsignal_stop    (struct ev_signal *w);

void evidle_start     (struct ev_idle *w);
void evidle_stop      (struct ev_idle *w);

void evprepare_start  (struct ev_prepare *w);
void evprepare_stop   (struct ev_prepare *w);

void evcheck_start    (struct ev_check *w);
void evcheck_stop     (struct ev_check *w);

void evchild_start    (struct ev_child *w);
void evchild_stop     (struct ev_child *w);
#endif

#endif