Dogcows Code - chaz/openbox/blob - otk/timer.cc

   1 // -*- mode: C++; indent-tabs-mode: nil; -*-
   2
   3 #ifdef    HAVE_CONFIG_H
   4 #  include "../config.h"
   5 #endif // HAVE_CONFIG_H
   6
   7 #include "timer.hh"
   8 #include "display.hh"
   9 #include "util.hh"
  10
  11 namespace otk {
  12
  13 static timeval normalizeTimeval(const timeval &tm)
  14 {
  15   timeval ret = tm;
  16
  17   while (ret.tv_usec < 0) {
  18     if (ret.tv_sec > 0) {
  19       --ret.tv_sec;
  20       ret.tv_usec += 1000000;
  21     } else {
  22       ret.tv_usec = 0;
  23     }
  24   }
  25
  26   if (ret.tv_usec >= 1000000) {
  27     ret.tv_sec += ret.tv_usec / 1000000;
  28     ret.tv_usec %= 1000000;
  29   }
  30
  31   if (ret.tv_sec < 0) ret.tv_sec = 0;
  32
  33   return ret;
  34 }
  35
  36
  37 OBTimer::OBTimer(OBTimerQueueManager *m, OBTimeoutHandler h, OBTimeoutData d)
  38 {
  39   manager = m;
  40   handler = h;
  41   data = d;
  42
  43   recur = timing = False;
  44 }
  45
  46
  47 OBTimer::~OBTimer(void)
  48 {
  49   if (timing) stop();
  50 }
  51
  52
  53 void OBTimer::setTimeout(long t)
  54 {
  55   _timeout.tv_sec = t / 1000;
  56   _timeout.tv_usec = t % 1000;
  57   _timeout.tv_usec *= 1000;
  58 }
  59
  60
  61 void OBTimer::setTimeout(const timeval &t)
  62 {
  63   _timeout.tv_sec = t.tv_sec;
  64   _timeout.tv_usec = t.tv_usec;
  65 }
  66
  67
  68 void OBTimer::start(void)
  69 {
  70   gettimeofday(&_start, 0);
  71
  72   if (! timing) {
  73     timing = True;
  74     manager->addTimer(this);
  75   }
  76 }
  77
  78
  79 void OBTimer::stop(void)
  80 {
  81   timing = False;
  82
  83   manager->removeTimer(this);
  84 }
  85
  86
  87 void OBTimer::halt(void)
  88 {
  89   timing = False;
  90 }
  91
  92
  93 void OBTimer::fireTimeout(void)
  94 {
  95   if (handler)
  96     handler(data);
  97 }
  98
  99
 100 timeval OBTimer::timeRemaining(const timeval &tm) const
 101 {
 102   timeval ret = endpoint();
 103
 104   ret.tv_sec  -= tm.tv_sec;
 105   ret.tv_usec -= tm.tv_usec;
 106
 107   return normalizeTimeval(ret);
 108 }
 109
 110
 111 timeval OBTimer::endpoint(void) const
 112 {
 113   timeval ret;
 114
 115   ret.tv_sec = _start.tv_sec + _timeout.tv_sec;
 116   ret.tv_usec = _start.tv_usec + _timeout.tv_usec;
 117
 118   return normalizeTimeval(ret);
 119 }
 120
 121
 122 bool OBTimer::shouldFire(const timeval &tm) const
 123 {
 124   timeval end = endpoint();
 125
 126   return ! ((tm.tv_sec < end.tv_sec) ||
 127             (tm.tv_sec == end.tv_sec && tm.tv_usec < end.tv_usec));
 128 }
 129
 130
 131 void OBTimerQueueManager::fire()
 132 {
 133   fd_set rfds;
 134   timeval now, tm, *timeout = (timeval *) 0;
 135
 136   const int xfd = ConnectionNumber(otk::OBDisplay::display);
 137
 138   FD_ZERO(&rfds);
 139   FD_SET(xfd, &rfds); // break on any x events
 140
 141   if (! timerList.empty()) {
 142     const OBTimer* const timer = timerList.top();
 143
 144     gettimeofday(&now, 0);
 145     tm = timer->timeRemaining(now);
 146
 147     timeout = &tm;
 148   }
 149
 150   select(xfd + 1, &rfds, 0, 0, timeout);
 151
 152   // check for timer timeout
 153   gettimeofday(&now, 0);
 154
 155   // there is a small chance for deadlock here:
 156   // *IF* the timer list keeps getting refreshed *AND* the time between
 157   // timer->start() and timer->shouldFire() is within the timer's period
 158   // then the timer will keep firing.  This should be VERY near impossible.
 159   while (! timerList.empty()) {
 160     OBTimer *timer = timerList.top();
 161     if (! timer->shouldFire(now))
 162       break;
 163
 164     timerList.pop();
 165
 166     timer->fireTimeout();
 167     timer->halt();
 168     if (timer->isRecurring())
 169       timer->start();
 170   }
 171 }
 172
 173
 174 void OBTimerQueueManager::addTimer(OBTimer *timer)
 175 {
 176   assert(timer);
 177   timerList.push(timer);
 178 }
 179
 180 void OBTimerQueueManager::removeTimer(OBTimer* timer)
 181 {
 182   assert(timer);
 183   timerList.release(timer);
 184 }
 185
 186 }