KernelLand/Kernel/time.c

   1 /*
   2  * Acess 2
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * Timer Code
   6  */
   7 #include <acess.h>
   8 #include <timers.h>
   9 #include <events.h>
  10 #include <hal_proc.h>   // Proc_GetCurThread
  11
  12 // === CONSTANTS ===
  13 #define NUM_TIMERS      8
  14
  15 // === TYPEDEFS ===
  16 struct sTimer {
  17         tTimer  *Next;
  18         Sint64  FiresAfter;
  19         void    (*Callback)(void*);
  20         void    *Argument;
  21 };
  22
  23 // === PROTOTYPES ===
  24 void    Timer_CallTimers(void);
  25
  26 // === GLOBALS ===
  27 volatile Uint64 giTicks = 0;
  28 volatile Sint64 giTimestamp = 0;
  29 volatile Uint64 giPartMiliseconds = 0;
  30 tTimer  *gTimers;       // TODO: Replace by a ring-list timer
  31
  32 // === CODE ===
  33 /**
  34  * \fn void Timer_CallTimers()
  35  */
  36 void Timer_CallTimers()
  37 {
  38         while( gTimers && gTimers->FiresAfter < now() )
  39         {
  40                 tTimer  *next;
  41
  42                 if( gTimers->Callback )
  43                         gTimers->Callback(gTimers->Argument);
  44                 else
  45                         Threads_PostEvent(gTimers->Argument, THREAD_EVENT_TIMER);
  46
  47                 next = gTimers->Next;
  48                 free(gTimers);
  49                 gTimers = next;
  50         }
  51 }
  52
  53 /**
  54  * \brief Schedule an action
  55  */
  56 tTimer *Time_CreateTimer(int Delta, tTimerCallback *Callback, void *Argument)
  57 {
  58         tTimer  *ret;
  59         tTimer  *t, *p;
  60
  61         if(Callback == NULL)
  62                 Argument = Proc_GetCurThread();
  63
  64         // TODO: Use a pool instead?
  65         ret = malloc(sizeof(tTimer));
  66
  67         ret->Callback = Callback;
  68         ret->FiresAfter = now() + Delta;
  69         ret->Argument = Argument;
  70
  71         // Add into list (sorted)
  72         for( p = (tTimer*)&gTimers, t = gTimers; t; p = t, t = t->Next )
  73         {
  74                 if( t->FiresAfter > ret->FiresAfter )   break;
  75         }
  76         ret->Next = t;
  77         p->Next = ret;
  78
  79         return ret;
  80 }
  81
  82 /**
  83  * \brief Delete a timer
  84  */
  85 void Time_RemoveTimer(tTimer *Timer)
  86 {
  87         tTimer  *t, *p;
  88         for( p = (tTimer*)&gTimers, t = gTimers; t; p = t, t = t->Next )
  89         {
  90                 if( t == Timer )
  91                 {
  92                         p->Next = t->Next;
  93                         free(Timer);
  94                         return ;
  95                 }
  96         }
  97 }
  98
  99 /**
 100  * \fn void Time_Delay(int Delay)
 101  * \brief Delay for a small ammount of time
 102  */
 103 void Time_Delay(int Delay)
 104 {
 105 //      tTime   dest = now() + Delay;
 106 //      while(dest > now())     Threads_Yield();
 107         Time_CreateTimer(Delay, NULL, NULL);
 108         Threads_WaitEvents(THREAD_EVENT_TIMER);
 109 }
 110
 111 // === EXPORTS ===
 112 EXPORT(Time_CreateTimer);
 113 EXPORT(Time_RemoveTimer);
 114 EXPORT(Time_Delay);