summaryrefslogtreecommitdiffstats
path: root/src/pulsecore/rtclock.c
blob: 5fc6da2bd65c1f4328af59fbcd9156a8919e46c3 (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
/***
  This file is part of PulseAudio.

  Copyright 2004-2006 Lennart Poettering
  Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB

  PulseAudio is free software; you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as
  published by the Free Software Foundation; either version 2.1 of the
  License, or (at your option) any later version.

  PulseAudio is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with PulseAudio; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stddef.h>
#include <time.h>
#include <sys/time.h>
#include <sys/prctl.h>
#include <errno.h>

#include <pulse/timeval.h>
#include <pulsecore/macro.h>
#include <pulsecore/core-error.h>

#include "rtclock.h"

pa_usec_t pa_rtclock_age(const struct timeval *tv) {
    struct timeval now;
    pa_assert(tv);

    return pa_timeval_diff(pa_rtclock_get(&now), tv);
}

struct timeval *pa_rtclock_get(struct timeval *tv) {
#ifdef HAVE_CLOCK_GETTIME
    struct timespec ts;

#ifdef CLOCK_MONOTONIC
    /* No locking or atomic ops for no_monotonic here */
    static pa_bool_t no_monotonic = FALSE;

    if (!no_monotonic)
        if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0)
            no_monotonic = TRUE;

    if (no_monotonic)
#endif
        pa_assert_se(clock_gettime(CLOCK_REALTIME, &ts) == 0);

    pa_assert(tv);

    tv->tv_sec = ts.tv_sec;
    tv->tv_usec = ts.tv_nsec / 1000;

    return tv;

#else /* HAVE_CLOCK_GETTIME */

    return pa_gettimeofday(tv);

#endif
}

pa_bool_t pa_rtclock_hrtimer(void) {
#ifdef HAVE_CLOCK_GETTIME
    struct timespec ts;

#ifdef CLOCK_MONOTONIC
    if (clock_getres(CLOCK_MONOTONIC, &ts) >= 0)
        return ts.tv_sec == 0 && ts.tv_nsec <= PA_HRTIMER_THRESHOLD_USEC*1000;
#endif

    pa_assert_se(clock_getres(CLOCK_REALTIME, &ts) == 0);
    return ts.tv_sec == 0 && ts.tv_nsec <= PA_HRTIMER_THRESHOLD_USEC*1000;

#else /* HAVE_CLOCK_GETTIME */

    return FALSE;

#endif
}

void pa_rtclock_hrtimer_enable(void) {
#ifdef PR_SET_TIMERSLACK
    int slack_ns;

    if ((slack_ns = prctl(PR_GET_TIMERSLACK, 0, 0, 0, 0)) < 0) {
        pa_log_info("PR_GET_TIMERSLACK/PR_SET_TIMERSLACK not supported.");
        return;
    }

    pa_log_debug("Timer slack set to %i us.", slack_ns/1000);

    slack_ns = 500000000;

    pa_log_debug("Setting timer slack to %i us.", slack_ns/1000);

    if (prctl(PR_SET_TIMERSLACK, slack_ns, 0, 0, 0) < 0) {
        pa_log_warn("PR_SET_TIMERSLACK failed: %s", pa_cstrerror(errno));
        return;
    }

#endif
}

pa_usec_t pa_rtclock_usec(void) {
    struct timeval tv;

    return pa_timeval_load(pa_rtclock_get(&tv));
}

struct timeval* pa_rtclock_from_wallclock(struct timeval *tv) {

#ifdef HAVE_CLOCK_GETTIME
    struct timeval wc_now, rt_now;

    pa_gettimeofday(&wc_now);
    pa_rtclock_get(&rt_now);

    pa_assert(tv);

    if (pa_timeval_cmp(&wc_now, tv) < 0)
        pa_timeval_add(&rt_now, pa_timeval_diff(tv, &wc_now));
    else
        pa_timeval_sub(&rt_now, pa_timeval_diff(&wc_now, tv));

    *tv = rt_now;
#endif

    return tv;
}