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
|
/************************************************************************
* sched/clock/clock_gettime.c
*
* Copyright (C) 2007, 2009, 2011, 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************************/
/************************************************************************
* Included Files
************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <time.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <arch/irq.h>
#include "clock/clock.h"
/************************************************************************
* Pre-processor Definitions
************************************************************************/
/************************************************************************
* Private Type Declarations
************************************************************************/
/************************************************************************
* Private Function Prototypes
************************************************************************/
/**********************************************************************
* Public Constant Data
**********************************************************************/
/************************************************************************
* Public Variables
************************************************************************/
/**********************************************************************
* Private Variables
**********************************************************************/
/************************************************************************
* Private Functions
************************************************************************/
/************************************************************************
* Public Functions
************************************************************************/
/************************************************************************
* Name: clock_gettime
*
* Description:
* Clock Functions based on POSIX APIs
*
************************************************************************/
int clock_gettime(clockid_t clock_id, struct timespec *tp)
{
struct timespec ts;
uint32_t carry;
int ret = OK;
sdbg("clock_id=%d\n", clock_id);
DEBUGASSERT(tp != NULL);
#ifdef CONFIG_CLOCK_MONOTONIC
/* CLOCK_MONOTONIC is an optional under POSIX: "If the Monotonic Clock
* option is supported, all implementations shall support a clock_id
* of CLOCK_MONOTONIC defined in <time.h>. This clock represents the
* monotonic clock for the system. For this clock, the value returned
* by clock_gettime() represents the amount of time (in seconds and
* nanoseconds) since an unspecified point in the past (for example,
* system start-up time, or the Epoch). This point does not change
* after system start-up time. The value of the CLOCK_MONOTONIC clock
* cannot be set via clock_settime(). This function shall fail if it
* is invoked with a clock_id argument of CLOCK_MONOTONIC."
*/
if (clock_id == CLOCK_MONOTONIC)
{
/* The the time elapsed since the timer was initialized at power on
* reset.
*/
ret = clock_systimespec(tp);
}
else
#endif
/* CLOCK_REALTIME - POSIX demands this to be present. CLOCK_REALTIME
* represents the machine's best-guess as to the current wall-clock,
* time-of-day time. This means that CLOCK_REALTIME can jump forward and
* backward as the system time-of-day clock is changed.
*/
if (clock_id == CLOCK_REALTIME)
{
/* Get the elapsedcd s time since the time-of-day was last set.
* clock_systimespec() provides the time since power was applied;
* the bias value corresponds to the time when the time-of-day was
* last set.
*/
ret = clock_systimespec(&ts);
if (ret == OK)
{
/* Add the base time to this. The base time is the time-of-day
* setting. When added to the elapsed time since the time-of-day
* was last set, this gives us the current time.
*/
ts.tv_sec += (uint32_t)g_basetime.tv_sec;
ts.tv_nsec += (uint32_t)g_basetime.tv_nsec;
/* Handle carry to seconds. */
if (ts.tv_nsec >= NSEC_PER_SEC)
{
carry = ts.tv_nsec / NSEC_PER_SEC;
ts.tv_sec += carry;
ts.tv_nsec -= (carry * NSEC_PER_SEC);
}
/* And return the result to the caller. */
tp->tv_sec = ts.tv_sec;
tp->tv_nsec = ts.tv_nsec;
}
}
else
{
ret = -EINVAL;
}
/* Check for errors and set the errno value if necessary */
if (ret < 0)
{
sdbg("Returning ERROR\n");
set_errno(-ret);
ret = ERROR;
}
else
{
sdbg("Returning tp=(%d,%d)\n", (int)tp->tv_sec, (int)tp->tv_nsec);
}
return ret;
}
|
