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
|
/**
* @file clockadj.h
* @brief Wraps clock_adjtime functionality.
* @note Copyright (C) 2013 Miroslav Lichvar <mlichvar@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef HAVE_CLOCKADJ_H
#define HAVE_CLOCKADJ_H
#include <inttypes.h>
#include <time.h>
/**
* Initialize state needed when adjusting or reading the clock.
* @param clkid A clock ID obtained using phc_open() or CLOCK_REALTIME.
*/
void clockadj_init(clockid_t clkid);
/**
* Set clock's frequency offset.
* @param clkid A clock ID obtained using phc_open() or CLOCK_REALTIME.
* @param freq The frequency offset in parts per billion (ppb).
* @return 0 on success, -1 on failure
*/
int clockadj_set_freq(clockid_t clkid, double freq);
/**
* Read clock's frequency offset.
* @param clkid A clock ID obtained using phc_open() or CLOCK_REALTIME.
* @return The frequency offset in parts per billion (ppb).
*/
double clockadj_get_freq(clockid_t clkid);
/**
* Set clock's phase offset.
* @param clkid A clock ID obtained using phc_open() or CLOCK_REALTIME.
* @param offset The phase offset in nanoseconds.
* @return 0 on success, -1 on failure
*/
int clockadj_set_phase(clockid_t clkid, long offset);
/**
* Step clock's time.
* @param clkid A clock ID obtained using phc_open() or CLOCK_REALTIME.
* @param step The time step in nanoseconds.
* @return 0 on success, -1 on failure
*/
int clockadj_step(clockid_t clkid, int64_t step);
/**
* Read maximum frequency adjustment of the target clock.
* @return The maximum frequency adjustment in parts per billion (ppb).
*/
int clockadj_max_freq(clockid_t clkid);
/**
* Compare offset between two clocks
* @param clkid A clock ID obtained using phc_open() or CLOCK_REALTIME
* @param sysclk A clock ID obtained using phc_open() or CLOCK_REALTIME
* @param readings Number of readings to try
* @param offset On return, the nanoseconds offset between the clocks
* @param ts On return, the time of sysclk in nanoseconds that was used
* @param delay On return, the interval between two reads of sysclk
* @return Zero on success, or negative error code on failure.
*
* Compare the offset between two clocks in a similar manner as the
* PTP_SYS_OFFSET ioctls. Performs multiple reads of sysclk with a read of
* clkid between in order to calculate the time difference of sysclk minus
* clkid.
*/
int clockadj_compare(clockid_t clkid, clockid_t sysclk, int readings,
int64_t *offset, uint64_t *ts, int64_t *delay);
/**
* Set the system clock to insert/delete leap second at midnight.
* @param leap +1 to insert leap second, -1 to delete leap second,
* 0 to reset the leap state.
*/
void sysclk_set_leap(int leap);
/**
* Set the TAI offset of the system clock to have correct CLOCK_TAI.
* @param offset The TAI-UTC offset in seconds.
*/
void sysclk_set_tai_offset(int offset);
/**
* Read maximum frequency adjustment of the system clock (CLOCK_REALTIME).
* @return The maximum frequency adjustment in parts per billion (ppb).
*/
int sysclk_max_freq(void);
/**
* Mark the system clock as synchronized to let the kernel synchronize
* the real-time clock (RTC) to it.
*/
void sysclk_set_sync(void);
#endif
|
