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"),
  95                 wxT("queued timer %p at tick %") wxLongLongFmtSpec _T("d"),
  96                desc->timer,  when.GetValue());
  97
  98     if ( m_timers )
  99     {
 100         wxTimerDesc *d = m_timers;
 101         while ( d->next && d->next->shotTime < when ) d = d->next;
 102         desc->next = d->next;
 103         desc->prev = d;
 104         if ( d->next )
 105             d->next->prev = desc;
 106         d->next = desc;
 107     }
 108     else
 109     {
 110         m_timers = desc;
 111         desc->prev = desc->next = NULL;
 112     }
 113 }
 114
 115 void wxTimerScheduler::RemoveTimer(wxTimerDesc *desc)
 116 {
 117     desc->running = FALSE;
 118     if ( desc == m_timers )
 119         m_timers = desc->next;
 120     if ( desc->prev )
 121         desc->prev->next = desc->next;
 122     if ( desc->next )
 123         desc->next->prev = desc->prev;
 124     desc->prev = desc->next = NULL;
 125 }
 126
 127 void wxTimerScheduler::NotifyTimers()
 128 {
 129     if ( m_timers )
 130     {
 131         bool oneShot;
 132         volatile bool timerDeleted;
 133         wxTimerTick_t now = GetMillisecondsTime();
 134         wxTimerDesc *desc;
 135
 136         while ( m_timers && m_timers->shotTime <= now )
 137         {
 138             desc = m_timers;
 139             oneShot = desc->timer->IsOneShot();
 140             RemoveTimer(desc);
 141
 142             timerDeleted = FALSE;
 143             desc->deleteFlag = &timerDeleted;
 144             desc->timer->Notify();
 145
 146             if ( !timerDeleted )
 147             {
 148                 wxLogTrace( wxT("timer"),
 149                             wxT("notified timer %p sheduled for %") wxLongLongFmtSpec _T("d"),
 150                             desc->timer, desc->shotTime.GetValue() );
 151
 152                 desc->deleteFlag = NULL;
 153                 if ( !oneShot )
 154                     QueueTimer(desc, now + desc->timer->GetInterval());
 155             }
 156         }
 157     }
 158 }
 159
 160
 161 // ----------------------------------------------------------------------------
 162 // wxTimer
 163 // ----------------------------------------------------------------------------
 164
 165 IMPLEMENT_ABSTRACT_CLASS(wxTimer,wxObject)
 166
 167 wxTimerScheduler *gs_scheduler = NULL;
 168
 169 void wxTimer::Init()
 170 {
 171     if ( !gs_scheduler )
 172         gs_scheduler = new wxTimerScheduler;
 173     m_desc = new wxTimerDesc(this);
 174 }
 175
 176 wxTimer::~wxTimer()
 177 {
 178     wxLogTrace( wxT("timer"), wxT("destroying timer %p..."), this);
 179     if ( IsRunning() )
 180         Stop();
 181
 182     // NB: this is a hack: wxTimerScheduler must have some way of knowing
 183     //     that wxTimer object was deleted under its hands -- this may
 184     //     happen if somebody is really nasty and deletes the timer
 185     //     from wxTimer::Notify()
 186     if ( m_desc->deleteFlag != NULL )
 187         *m_desc->deleteFlag = TRUE;
 188
 189     delete m_desc;
 190     wxLogTrace( wxT("timer"), wxT("    ...done destroying timer %p..."), this);
 191 }
 192
 193 bool wxTimer::IsRunning() const
 194 {
 195     return m_desc->running;
 196 }
 197
 198 bool wxTimer::Start(int millisecs, bool oneShot)
 199 {
 200     wxLogTrace( wxT("timer"), wxT("started timer %p: %i ms, oneshot=%i"),
 201                this, millisecs, oneShot);
 202
 203     if ( !wxTimerBase::Start(millisecs, oneShot) )
 204         return FALSE;
 205
 206     gs_scheduler->QueueTimer(m_desc);
 207     return TRUE;
 208 }
 209
 210 void wxTimer::Stop()
 211 {
 212     if ( !m_desc->running ) return;
 213
 214     gs_scheduler->RemoveTimer(m_desc);
 215 }
 216
 217 /*static*/ void wxTimer::NotifyTimers()
 218 {
 219     if ( gs_scheduler )
 220         gs_scheduler->NotifyTimers();
 221 }
 222
 223
 224
 225 // A module to deallocate memory properly:
 226 class wxTimerModule: public wxModule
 227 {
 228 DECLARE_DYNAMIC_CLASS(wxTimerModule)
 229 public:
 230     wxTimerModule() {}
 231     bool OnInit() { return TRUE; }
 232     void OnExit() { delete gs_scheduler; gs_scheduler = NULL; }
 233 };
 234
 235 IMPLEMENT_DYNAMIC_CLASS(wxTimerModule, wxModule)
 236
 237
 238 #endif //wxUSE_TIMER