timer.c revision 156136 
1/*
2 * Copyright (c) 2006 David Xu <davidxu@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice unmodified, this list of conditions, and the following
10 *    disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD: head/lib/librt/timer.c 156136 2006-03-01 06:37:34Z davidxu $
27 *
28 */
29
30#include <sys/cdefs.h>
31#include <sys/types.h>
32#include <sys/syscall.h>
33
34#include "namespace.h"
35#include <errno.h>
36#include <pthread.h>
37#include <stddef.h>
38#include <signal.h>
39#include <stdlib.h>
40#include <time.h>
41#include <unistd.h>
42#include "sigev_thread.h"
43#include "un-namespace.h"
44
45extern int __sys_ktimer_create(clockid_t, struct sigevent *__restrict,
46	int *__restrict);
47extern int __sys_ktimer_delete(int);
48extern int __sys_ktimer_gettime(int, struct itimerspec *);
49extern int __sys_ktimer_getoverrun(int);
50extern int __sys_ktimer_settime(int, int,
51	const struct itimerspec *__restrict, struct itimerspec *__restrict);
52
53struct __timer {
54	int oshandle;
55	struct sigev_node *node;
56};
57
58__weak_reference(__timer_create, timer_create);
59__weak_reference(__timer_create, _timer_create);
60__weak_reference(__timer_delete, timer_delete);
61__weak_reference(__timer_delete, _timer_delete);
62__weak_reference(__timer_gettime, timer_gettime);
63__weak_reference(__timer_gettime, _timer_gettime);
64__weak_reference(__timer_settime, timer_settime);
65__weak_reference(__timer_settime, _timer_settime);
66__weak_reference(__timer_getoverrun, timer_getoverrun);
67__weak_reference(__timer_getoverrun, _timer_getoverrun);
68
69typedef void (*timer_func)(union sigval val, int timerid, int overrun);
70
71static void
72timer_dispatch(struct sigev_node *sn, siginfo_t *si)
73{
74	timer_func f = sn->sn_func;
75
76	/* I want to avoid expired notification. */
77	if (si->si_value.sival_int == sn->sn_gen)
78		f(sn->sn_value, si->si_timerid, si->si_overrun);
79}
80
81int
82__timer_create(clockid_t clockid, struct sigevent *evp, timer_t *timerid)
83{
84	struct __timer *timer;
85	struct sigevent ev;
86	struct sigev_node *sn;
87	int ret, err;
88
89	timer = malloc(sizeof(struct __timer));
90	if (timer == NULL)
91		return (-1);
92
93	if (evp == NULL || evp->sigev_notify != SIGEV_THREAD) {
94		ret = __sys_ktimer_create(clockid, evp, &timer->oshandle);
95		if (ret == -1) {
96			err = errno;
97			free(timer);
98			errno = err;
99			return (ret);
100		}
101		timer->node = NULL;
102		*timerid = timer;
103		return (0);
104	}
105
106	if (__sigev_check_init()) {
107		errno = EINVAL;
108		return (-1);
109	}
110
111	sn = __sigev_alloc(SI_TIMER, evp);
112	if (sn == NULL) {
113		errno = EAGAIN;
114		return (-1);
115	}
116
117	__sigev_get_sigevent(sn, &ev, sn->sn_gen);
118	ret = __sys_ktimer_create(clockid, &ev, &timer->oshandle);
119	if (ret != 0) {
120		err = errno;
121		__sigev_free(sn);
122		free(timer);
123		errno = err;
124		return (-1);
125	}
126	sn->sn_dispatch = timer_dispatch;
127	sn->sn_id = timer->oshandle;
128	__sigev_list_lock();
129	__sigev_register(sn);
130	__sigev_list_unlock();
131	*timerid = timer;
132	return (0);
133}
134
135int
136__timer_delete(timer_t timerid)
137{
138	int ret, err;
139
140	if (timerid->node != NULL) {
141		__sigev_list_lock();
142		__sigev_delete_node(timerid->node);
143		__sigev_list_unlock();
144	}
145	ret = __sys_ktimer_delete(timerid->oshandle);
146	err = errno;
147	free(timerid);
148	errno = err;
149	return (ret);
150}
151
152int
153__timer_gettime(timer_t timerid, struct itimerspec *value)
154{
155
156	return __sys_ktimer_gettime(timerid->oshandle, value);
157}
158
159int
160__timer_getoverrun(timer_t timerid)
161{
162
163	return __sys_ktimer_getoverrun(timerid->oshandle);
164}
165
166int
167__timer_settime(timer_t timerid, int flags,
168	const struct itimerspec *__restrict value,
169	struct itimerspec *__restrict ovalue)
170{
171
172	return __sys_ktimer_settime(timerid->oshandle,
173		flags, value, ovalue);
174}
175
176int
177__timer_oshandle(timer_t timerid)
178{
179
180	return (timerid->oshandle);
181}
182