summaryrefslogtreecommitdiff
path: root/minecproxy/ptimer.c
blob: 1ef76094e98148b17d1d25733b40333b9e392e9c (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
/* SPDX-License-Identifier: GPL-2.0 */
#include <inttypes.h>
#include <sys/timerfd.h>
#include <string.h>
#include <unistd.h>
#include <time.h>

#include "main.h"
#include "uring.h"
#include "ptimer.h"

struct ptimer {
	uint64_t value;
	time_t previous_time;
	struct uring_task task;
	unsigned task_count;
	struct list_head ptasks;
};

static void ptimer_set(unsigned value, unsigned interval)
{
	struct itimerspec tspec = {
		.it_interval = { .tv_sec = interval, .tv_nsec = 0 },
		.it_value = { .tv_sec = value, .tv_nsec = 0 }
	};

	assert_return(cfg->ptimer && cfg->ptimer->task.fd >= 0);

	if (timerfd_settime(cfg->ptimer->task.fd, 0, &tspec, NULL) != 0)
		error("timerfd_settime: %m");
}

static unsigned gcd(unsigned a, unsigned b)
{
	if (a == 0)
		return b;
	return gcd(b % a, a);
}

static unsigned array_gcd(unsigned arr[], unsigned n)
{
	unsigned result = arr[0];

	for (unsigned i = 1; i < n; i++)
		result = gcd(arr[i], result);

	return result;
}

static void ptimer_tick(struct ptimer *ptimer)
{
	time_t now = time(NULL);
	unsigned diff = (unsigned)(now - ptimer->previous_time);
	struct ptimer_task *ptask, *ptmp;

	debug(DBG_TIMER, "got a tick of %u secs", diff);
	list_for_each_entry_safe(ptask, ptmp, &ptimer->ptasks, list) {
		if (ptask->remain > diff) {
			ptask->remain -= diff;
			continue;
		}

		debug(DBG_TIMER, "triggering ptask %p (times %u)", ptask,
		      ptask->times);

		ptask->cb(ptask);
		ptask->remain = ptask->interval;

		if (ptask->times == 0)
			continue;

		ptask->times--;
		if (ptask->times == 0) {
			ptask->active = false;
			list_del(&ptask->list);
		}
	}

	ptimer->previous_time = now;
}

static void ptimer_reconfig(struct ptimer *ptimer)
{
	struct ptimer_task *ptask;
	unsigned i = 0;
	unsigned lowest = ~0;
	unsigned interval;

	if (list_empty(&ptimer->ptasks)) {
		debug(DBG_TIMER, "no tasks");
		ptimer_set(0, 0);
		return;
	}

	unsigned intervals[ptimer->task_count];

	list_for_each_entry(ptask, &ptimer->ptasks, list) {
		if (ptask->remain < lowest)
			lowest = ptask->remain;
		intervals[i++] = ptask->interval;
	}

	interval = array_gcd(intervals, i);

	debug(DBG_TIMER, "lowest: %u, gcd: %u\n", lowest, interval);
	ptimer_set(lowest, interval);
}

void ptimer_del_task(struct ptimer_task *ptask)
{
	struct ptimer *ptimer = cfg->ptimer;

	assert_return(ptask && ptimer);
	assert_return_silent(ptask->active);
	assert_return(ptimer->task_count > 0);

	list_del(&ptask->list);
	ptask->active = false;
	ptimer->task_count--;
	ptimer_tick(ptimer);
	ptimer_reconfig(ptimer);
	uring_task_put(&ptimer->task);
}

void ptimer_add_task(struct ptimer_task *ptask)
{
	struct ptimer *ptimer = cfg->ptimer;

	assert_return(ptask && ptask->interval > 0 && ptask->cb && ptimer);
	assert_return_silent(!ptask->active);

	uring_task_get(&ptimer->task);
	ptask->active = true;
	ptask->remain = ptask->interval;
	ptimer_tick(ptimer);
	list_add(&ptask->list, &ptimer->ptasks);
	ptimer->task_count++;
	ptimer_reconfig(ptimer);
}

void ptimer_refdump()
{
	assert_return(cfg->ptimer);

	uring_task_refdump(&cfg->ptimer->task);
}

static void ptimer_free(struct uring_task *task)
{
	struct ptimer *ptimer = container_of(task, struct ptimer, task);

	assert_return(task);

	debug(DBG_TIMER, "task %p, ptimer %p", task, ptimer);
	xfree(ptimer);
	cfg->ptimer = NULL;
}

void ptimer_delete()
{
	assert_return(cfg->ptimer);

	debug(DBG_TIMER, "closing fd %i", cfg->ptimer->task.fd);
	uring_task_destroy(&cfg->ptimer->task);
}

static void ptimer_cb(struct uring_task *task, int res)
{
	struct ptimer *ptimer = container_of(task, struct ptimer, task);

	assert_return(task);
	assert_task_alive(DBG_IGMP, task);

	if (res != sizeof(ptimer->value)) {
		error("timerfd_read: res: %i, %m", res);
		return;
	}

	ptimer_tick(ptimer);
	uring_read(&ptimer->task, &ptimer->value, sizeof(ptimer->value),
		   ptimer_cb);
}

void ptimer_init()
{
	struct ptimer *ptimer;
	int tfd;

	assert_return(!cfg->ptimer);

	ptimer = zmalloc(sizeof(*ptimer));
	if (!ptimer)
		die("malloc: %m");

	tfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
	if (tfd < 0)
		die("timerfd_create: %m");

	ptimer->task_count = 0;
	ptimer->previous_time = time(NULL);
	INIT_LIST_HEAD(&ptimer->ptasks);
	uring_task_init(&ptimer->task, "ptimer", uring_parent(), ptimer_free);
	uring_task_set_fd(&ptimer->task, tfd);
	cfg->ptimer = ptimer;
	uring_read(&ptimer->task, &ptimer->value, sizeof(ptimer->value),
		   ptimer_cb);
}