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
|
/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT 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 3 of the License, or
(at your option) any later version.
ChibiOS/RT 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, see <http://www.gnu.org/licenses/>.
*/
/**
* @file chvt.c
* @brief Time and Virtual Timers related code.
*
* @addtogroup time
* @details Time and Virtual Timers related APIs and services.
* @{
*/
#include "ch.h"
/**
* @brief Virtual timers delta list header.
*/
VTList vtlist;
/**
* @brief Virtual Timers initialization.
* @note Internal use only.
*
* @notapi
*/
void vt_init(void) {
vtlist.vt_next = vtlist.vt_prev = (void *)&vtlist;
vtlist.vt_time = (systime_t)-1;
vtlist.vt_systime = 0;
}
/**
* @brief Enables a virtual timer.
* @note The associated function is invoked by an interrupt handler within
* the I-Locked state, see @ref system_states.
*
* @param[out] vtp the @p VirtualTimer structure pointer
* @param[in] time the number of ticks before the operation timeouts, the
* special values are handled as follow:
* - @a TIME_INFINITE is allowed but interpreted as a
* normal time specification.
* - @a TIME_IMMEDIATE this value is not allowed.
* .
* @param[in] vtfunc the timer callback function. After invoking the
* callback the timer is disabled and the structure can
* be disposed or reused.
* @param[in] par a parameter that will be passed to the callback
* function
*
* @iclass
*/
void chVTSetI(VirtualTimer *vtp, systime_t time, vtfunc_t vtfunc, void *par) {
VirtualTimer *p;
chDbgCheck((vtp != NULL) && (vtfunc != NULL) && (time != TIME_IMMEDIATE),
"chVTSetI");
vtp->vt_par = par;
vtp->vt_func = vtfunc;
p = vtlist.vt_next;
while (p->vt_time < time) {
time -= p->vt_time;
p = p->vt_next;
}
vtp->vt_prev = (vtp->vt_next = p)->vt_prev;
vtp->vt_prev->vt_next = p->vt_prev = vtp;
vtp->vt_time = time;
if (p != (void *)&vtlist)
p->vt_time -= time;
}
/**
* @brief Disables a Virtual Timer.
* @note The timer MUST be active when this function is invoked.
*
* @param[in] vtp the @p VirtualTimer structure pointer
*
* @iclass
*/
void chVTResetI(VirtualTimer *vtp) {
chDbgCheck(vtp != NULL, "chVTResetI");
chDbgAssert(vtp->vt_func != NULL,
"chVTResetI(), #1",
"timer not set or already triggered");
if (vtp->vt_next != (void *)&vtlist)
vtp->vt_next->vt_time += vtp->vt_time;
vtp->vt_prev->vt_next = vtp->vt_next;
vtp->vt_next->vt_prev = vtp->vt_prev;
vtp->vt_func = (vtfunc_t)NULL;
}
/**
* @brief Checks if the current system time is within the specified time
* window.
* @note When start==end then the function returns always true because the
* whole time range is specified.
*
* @param[in] start the start of the time window (inclusive)
* @param[in] end the end of the time window (non inclusive)
* @retval TRUE current time within the specified time window.
* @retval FALSE current time not within the specified time window.
*
* @api
*/
bool_t chTimeIsWithin(systime_t start, systime_t end) {
systime_t time = chTimeNow();
return end > start ? (time >= start) && (time < end) :
(time >= start) || (time < end);
}
/** @} */
|