wiring-timer/Timer.cpp at master · dniklaus/wiring-timer · GitHub

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
/*
 * Timer.cpp
 *
 *  Created on: 13.08.2013
 *      Author: niklausd
 */

#include <limits.h>
#include "UptimeInfo.h"
#include "TimerContext.h"
#include "Timer.h"

void scheduleTimers()
{
  TimerContext::instance()->handleTick();
}

void delayAndSchedule(unsigned long delayMillis)
{
  // create a one-shot timer on the fly
  Timer delayTimer(0, Timer::IS_NON_RECURRING, (delayMillis));

  // wait until the timer expires
  while (!delayTimer.isTimerExpired())
  {
    // schedule the timer above and all the other timers, so they will still run in 'parallel'
    scheduleTimers();
  }
}

const bool Timer::IS_NON_RECURRING = false;
const bool Timer::IS_RECURRING     = true;

Timer::Timer(TimerAdapter* adapter, bool isRecurring, unsigned long timeMillis)
: m_isRunning(false)
, m_isRecurring(isRecurring)
, m_isExpiredFlag(false)
, m_willOverflow(false)
, m_currentTimeMillis(0)
, m_triggerTimeMillis(0)
, m_triggerTimeMillisUpperLimit(ULONG_MAX)
, m_delayMillis(timeMillis)
, m_adapter(adapter)
, m_next(0)
{
  TimerContext::instance()->attach(this);

  if (0 < m_delayMillis)
  {
    startTimer();
  }
}

Timer::~Timer()
{
  TimerContext::instance()->detach(this);
}

void Timer::attachAdapter(TimerAdapter* adapter)
{
  m_adapter = adapter;
}

TimerAdapter* Timer::adapter()
{
  return m_adapter;
}

Timer* Timer::next()
{
  return m_next;
}

void Timer::setNext(Timer* timer)
{
  m_next = timer;
}


bool Timer::isTimerExpired()
{
  internalTick();
  bool isExpired = m_isExpiredFlag;
  m_isExpiredFlag = false;
  return isExpired;
}

bool Timer::isRunning()
{
  return m_isRunning;
}

void Timer::tick()
{
  internalTick();
}

void Timer::cancelTimer()
{
  m_isRunning = false;
  m_isExpiredFlag = false;
}

void Timer::startTimer(unsigned long timeMillis)
{
  m_isRunning = true;
  m_delayMillis = timeMillis;
  m_currentTimeMillis = UptimeInfo::Instance()->tMillis();
  startInterval();
}

void Timer::startTimer()
{
  m_isRunning = true;
  m_currentTimeMillis = UptimeInfo::Instance()->tMillis();
  startInterval();
}

void Timer::startInterval()
{
  unsigned long deltaTime = ULONG_MAX - m_currentTimeMillis;
  m_willOverflow = (deltaTime < m_delayMillis);
  if (m_willOverflow)
  {
    // overflow will occur
    m_triggerTimeMillis = m_delayMillis - deltaTime - 1;
    m_triggerTimeMillisUpperLimit = m_currentTimeMillis;
  }
  else
  {
    m_triggerTimeMillis = m_currentTimeMillis + m_delayMillis;
    m_triggerTimeMillisUpperLimit = ULONG_MAX - deltaTime;
  }
}

void Timer::internalTick()
{
  bool intervalIsOver = false;

  m_currentTimeMillis = UptimeInfo::Instance()->tMillis();

  // check if interval is over as long as the timer shall be running
  if (m_isRunning)
  {
    if (m_willOverflow)
    {
      intervalIsOver = ((m_triggerTimeMillis <= m_currentTimeMillis) && (m_currentTimeMillis < m_triggerTimeMillisUpperLimit));
    }
    else
    {
      intervalIsOver = ((m_triggerTimeMillis <= m_currentTimeMillis) || (m_currentTimeMillis < m_triggerTimeMillisUpperLimit));
    }

    if (intervalIsOver)
    {
      // interval is over
      if (m_isRecurring)
      {
        // start next interval
        startInterval();
      }
      else
      {
        m_isRunning = false;
      }

      m_isExpiredFlag = true;
      if (0 != m_adapter)
      {
        m_adapter->timeExpired();
      }
    }
  }
}