src/generic/timer.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        mgl/timer.cpp
   3 // Purpose:     wxTimer implementation
   4 // Author:      Vaclav Slavik
   5 // Id:          $Id$
   6 // Copyright:   (c) Vaclav Slavik
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 #ifdef __GNUG__
  11 #pragma implementation "timer.h"
  12 #endif
  13
  14 // For compilers that support precompilation, includes "wx.h".
  15 #include "wx/wxprec.h"
  16
  17 #ifdef __BORLANDC__
  18     #pragma hdrstop
  19 #endif
  20
  21 // ----------------------------------------------------------------------------
  22 // NB: when using generic wxTimer implementation in your port, you *must* call
  23 //     wxTimer::NotifyTimers() often enough. The ideal place for this
  24 //     is in wxEventLoop::Dispatch().
  25 // ----------------------------------------------------------------------------
  26
  27 #include "wx/timer.h"
  28
  29 #if wxUSE_TIMER
  30
  31 #include "wx/log.h"
  32 #include "wx/module.h"
  33
  34 // ----------------------------------------------------------------------------
  35 // Time input function
  36 // ----------------------------------------------------------------------------
  37
  38 #ifdef __WXMGL__
  39     // We take advantage of wxMGL's _EVT_getTicks because it is faster
  40     // (especially under MS-DOS!) and more precise than wxGetLocalTimeMillis
  41     // if we are unlucky and the latter combines information from two sources.
  42     #include "wx/mgl/private.h"
  43     extern "C" ulong _EVT_getTicks();
  44     #define GetMillisecondsTime _EVT_getTicks
  45
  46     typedef ulong wxTimerTick_t;
  47 #else
  48     #define GetMillisecondsTime wxGetLocalTimeMillis
  49
  50     typedef wxLongLong wxTimerTick_t;
  51 #endif
  52
  53 // ----------------------------------------------------------------------------
  54 // helper structures and wxTimerScheduler
  55 // ----------------------------------------------------------------------------
  56
  57 class wxTimerDesc
  58 {
  59 public:
  60     wxTimerDesc(wxTimer *t) :
  61         timer(t), running(FALSE), next(NULL), prev(NULL),
  62         shotTime(0), deleteFlag(NULL) {}
  63
  64     wxTimer         *timer;
  65     bool             running;
  66     wxTimerDesc     *next, *prev;
  67     wxTimerTick_t    shotTime;
  68     volatile bool   *deleteFlag; // see comment in ~wxTimer
  69 };
  70
  71 class wxTimerScheduler
  72 {
  73 public:
  74     wxTimerScheduler() : m_timers(NULL) {}
  75
  76     void QueueTimer(wxTimerDesc *desc, wxTimerTick_t when = 0);
  77     void RemoveTimer(wxTimerDesc *desc);
  78     void NotifyTimers();
  79
  80 private:
  81     wxTimerDesc *m_timers;
  82 };
  83
  84 void wxTimerScheduler::QueueTimer(wxTimerDesc *desc, wxTimerTick_t when)
  85 {
  86     if ( desc->running )
  87         return; // already scheduled
  88
  89     if ( when == 0 )
  90         when = GetMillisecondsTime() + desc->timer->GetInterval();
  91     desc->shotTime = when;
  92     desc->running = TRUE;
  93
  94     wxLogTrace( wxT("timer"), wxT("queued timer %p at tick %ld"),
  95                desc->timer, (long) when);
  96
  97     if ( m_timers )
  98     {
  99         wxTimerDesc *d = m_timers;
 100         while ( d->next && d->next->shotTime < when ) d = d->next;
 101         desc->next = d->next;
 102         desc->prev = d;
 103         if ( d->next )
 104             d->next->prev = desc;
 105         d->next = desc;
 106     }
 107     else
 108     {
 109         m_timers = desc;
 110         desc->prev = desc->next = NULL;
 111     }
 112 }
 113
 114 void wxTimerScheduler::RemoveTimer(wxTimerDesc *desc)
 115 {
 116     desc->running = FALSE;
 117     if ( desc == m_timers )
 118         m_timers = desc->next;
 119     if ( desc->prev )
 120         desc->prev->next = desc->next;
 121     if ( desc->next )
 122         desc->next->prev = desc->prev;
 123     desc->prev = desc->next = NULL;
 124 }
 125
 126 void wxTimerScheduler::NotifyTimers()
 127 {
 128     if ( m_timers )
 129     {
 130         bool oneShot;
 131         volatile bool timerDeleted;
 132         wxTimerTick_t now = GetMillisecondsTime();
 133         wxTimerDesc *desc;
 134
 135         while ( m_timers && m_timers->shotTime <= now )
 136         {
 137             desc = m_timers;
 138             oneShot = desc->timer->IsOneShot();
 139             RemoveTimer(desc);
 140
 141             timerDeleted = FALSE;
 142             desc->deleteFlag = &timerDeleted;
 143             desc->timer->Notify();
 144
 145             if ( !timerDeleted )
 146             {
 147                 wxLogTrace( wxT("timer"),
 148                             wxT("notified timer %p sheduled for %" wxLongLongFmtSpec),
 149                             desc->timer, desc->shotTime );
 150
 151                 desc->deleteFlag = NULL;
 152                 if ( !oneShot )
 153                     QueueTimer(desc, now + desc->timer->GetInterval());
 154             }
 155         }
 156     }
 157 }
 158
 159
 160 // ----------------------------------------------------------------------------
 161 // wxTimer
 162 // ----------------------------------------------------------------------------
 163
 164 IMPLEMENT_ABSTRACT_CLASS(wxTimer,wxObject)
 165
 166 wxTimerScheduler *gs_scheduler = NULL;
 167
 168 void wxTimer::Init()
 169 {
 170     if ( !gs_scheduler )
 171         gs_scheduler = new wxTimerScheduler;
 172     m_desc = new wxTimerDesc(this);
 173 }
 174
 175 wxTimer::~wxTimer()
 176 {
 177     wxLogTrace( wxT("timer"), wxT("destroying timer %p..."), this);
 178     if ( IsRunning() )
 179         Stop();
 180
 181     // NB: this is a hack: wxTimerScheduler must have some way of knowing
 182     //     that wxTimer object was deleted under its hands -- this may
 183     //     happen if somebody is really nasty and deletes the timer
 184     //     from wxTimer::Notify()
 185     if ( m_desc->deleteFlag != NULL )
 186         *m_desc->deleteFlag = TRUE;
 187
 188     delete m_desc;
 189     wxLogTrace( wxT("timer"), wxT("    ...done destroying timer %p..."), this);
 190 }
 191
 192 bool wxTimer::IsRunning() const
 193 {
 194     return m_desc->running;
 195 }
 196
 197 bool wxTimer::Start(int millisecs, bool oneShot)
 198 {
 199     wxLogTrace( wxT("timer"), wxT("started timer %p: %i ms, oneshot=%i"),
 200                this, millisecs, oneShot);
 201
 202     if ( !wxTimerBase::Start(millisecs, oneShot) )
 203         return FALSE;
 204
 205     gs_scheduler->QueueTimer(m_desc);
 206     return TRUE;
 207 }
 208
 209 void wxTimer::Stop()
 210 {
 211     if ( !m_desc->running ) return;
 212
 213     gs_scheduler->RemoveTimer(m_desc);
 214 }
 215
 216 /*static*/ void wxTimer::NotifyTimers()
 217 {
 218     if ( gs_scheduler )
 219         gs_scheduler->NotifyTimers();
 220 }
 221
 222
 223
 224 // A module to deallocate memory properly:
 225 class wxTimerModule: public wxModule
 226 {
 227 DECLARE_DYNAMIC_CLASS(wxTimerModule)
 228 public:
 229     wxTimerModule() {}
 230     bool OnInit() { return TRUE; }
 231     void OnExit() { delete gs_scheduler; gs_scheduler = NULL; }
 232 };
 233
 234 IMPLEMENT_DYNAMIC_CLASS(wxTimerModule, wxModule)
 235
 236
 237 #endif //wxUSE_TIMER