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
|
/* Copyright (c) 2015-2017, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file periodic.c
*
* \brief Generic backend for handling periodic events.
*
* The events in this module are used by main.c to track items that need
* to fire once every N seconds, possibly picking a new interval each time
* that they fire. See periodic_events[] in main.c for examples.
*/
#include "or.h"
#include "compat_libevent.h"
#include "config.h"
#include "periodic.h"
/** We disable any interval greater than this number of seconds, on the
* grounds that it is probably an absolute time mistakenly passed in as a
* relative time.
*/
static const int MAX_INTERVAL = 10 * 365 * 86400;
/** Set the event <b>event</b> to run in <b>next_interval</b> seconds from
* now. */
static void
periodic_event_set_interval(periodic_event_item_t *event,
time_t next_interval)
{
tor_assert(next_interval < MAX_INTERVAL);
struct timeval tv;
tv.tv_sec = next_interval;
tv.tv_usec = 0;
mainloop_event_schedule(event->ev, &tv);
}
/** Wraps dispatches for periodic events, <b>data</b> will be a pointer to the
* event that needs to be called */
static void
periodic_event_dispatch(mainloop_event_t *ev, void *data)
{
periodic_event_item_t *event = data;
tor_assert(ev == event->ev);
time_t now = time(NULL);
const or_options_t *options = get_options();
// log_debug(LD_GENERAL, "Dispatching %s", event->name);
int r = event->fn(now, options);
int next_interval = 0;
/* update the last run time if action was taken */
if (r==0) {
log_err(LD_BUG, "Invalid return value for periodic event from %s.",
event->name);
tor_assert(r != 0);
} else if (r > 0) {
event->last_action_time = now;
/* If the event is meant to happen after ten years, that's likely
* a bug, and somebody gave an absolute time rather than an interval.
*/
tor_assert(r < MAX_INTERVAL);
next_interval = r;
} else {
/* no action was taken, it is likely a precondition failed,
* we should reschedule for next second incase the precondition
* passes then */
next_interval = 1;
}
// log_debug(LD_GENERAL, "Scheduling %s for %d seconds", event->name,
// next_interval);
struct timeval tv = { next_interval , 0 };
mainloop_event_schedule(ev, &tv);
}
/** Schedules <b>event</b> to run as soon as possible from now. */
void
periodic_event_reschedule(periodic_event_item_t *event)
{
/* Don't reschedule a disabled event. */
if (periodic_event_is_enabled(event)) {
periodic_event_set_interval(event, 1);
}
}
/** Initializes the libevent backend for a periodic event. */
void
periodic_event_setup(periodic_event_item_t *event)
{
if (event->ev) { /* Already setup? This is a bug */
log_err(LD_BUG, "Initial dispatch should only be done once.");
tor_assert(0);
}
event->ev = mainloop_event_new(periodic_event_dispatch,
event);
tor_assert(event->ev);
}
/** Handles initial dispatch for periodic events. It should happen 1 second
* after the events are created to mimic behaviour before #3199's refactor */
void
periodic_event_launch(periodic_event_item_t *event)
{
if (! event->ev) { /* Not setup? This is a bug */
log_err(LD_BUG, "periodic_event_launch without periodic_event_setup");
tor_assert(0);
}
/* Event already enabled? This is a bug */
if (periodic_event_is_enabled(event)) {
log_err(LD_BUG, "periodic_event_launch on an already enabled event");
tor_assert(0);
}
// Initial dispatch
periodic_event_dispatch(event->ev, event);
event->enabled = 1;
}
/** Release all storage associated with <b>event</b> */
void
periodic_event_destroy(periodic_event_item_t *event)
{
if (!event)
return;
mainloop_event_free(event->ev);
event->last_action_time = 0;
event->enabled = 0;
}
|
