Kernel/time.c

   1 /*
   2  * Acess 2
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * Timer Code
   6  */
   7 #include <acess.h>
   8
   9 // === CONSTANTS ===
  10 #define NUM_TIMERS      8
  11
  12 // === TYPEDEFS ===
  13 typedef struct sTimer {
  14          int    FiresAfter;
  15         void    (*Callback)(void*);
  16         void    *Argument;
  17 } tTimer;
  18
  19 // === PROTOTYPES ===
  20 Sint64  now(void);
  21 void    Timer_CallTimers(void);
  22
  23 // === GLOBALS ===
  24 Uint64  giTicks = 0;
  25 Sint64  giTimestamp = 0;
  26 Uint64  giPartMiliseconds = 0;
  27 tTimer  gTimers[NUM_TIMERS];
  28
  29 // === CODE ===
  30 /**
  31  * \fn Sint64 now()
  32  * \brief Return the current timestamp
  33  */
  34 Sint64 now(void)
  35 {
  36         return giTimestamp;
  37 }
  38
  39 /**
  40  * \fn void Timer_CallTimers()
  41  */
  42 void Timer_CallTimers()
  43 {
  44          int    i;
  45         void    (*callback)(void *);
  46
  47         for(i = 0;
  48                 i < NUM_TIMERS;
  49                 i ++)
  50         {
  51                 if(gTimers[i].Callback == NULL) continue;
  52                 if(giTimestamp < gTimers[i].FiresAfter) continue;
  53                 callback = gTimers[i].Callback;
  54                 gTimers[i].Callback = NULL;
  55                 callback(gTimers[i].Argument);
  56         }
  57 }
  58
  59 /**
  60  * \fn int Time_CreateTimer(int Delta, void *Callback, void *Argument)
  61  */
  62 int Time_CreateTimer(int Delta, void *Callback, void *Argument)
  63 {
  64          int    ret;
  65
  66         if(Callback == NULL)    return -1;
  67
  68         for(ret = 0;
  69                 ret < NUM_TIMERS;
  70                 ret++)
  71         {
  72                 if(gTimers[ret].Callback != NULL)       continue;
  73                 gTimers[ret].Callback = Callback;
  74                 gTimers[ret].FiresAfter = giTimestamp + Delta;
  75                 gTimers[ret].Argument = Argument;
  76                 //Log("Callback = %p", Callback);
  77                 //Log("Timer %i fires at %lli", ret, gTimers[ret].FiresAfter);
  78                 return ret;
  79         }
  80         return -1;
  81 }
  82
  83 /**
  84  * \fn void Time_RemoveTimer(int ID)
  85  */
  86 void Time_RemoveTimer(int ID)
  87 {
  88         if(ID < 0 || ID >= NUM_TIMERS)  return;
  89         gTimers[ID].Callback = NULL;
  90 }
  91
  92 /**
  93  * \fn void Time_Delay(int Delay)
  94  * \brief Delay for a small ammount of time
  95  */
  96 void Time_Delay(int Delay)
  97 {
  98         Sint64  dest = giTimestamp + Delay;
  99         while(dest < giTimestamp)       Threads_Yield();
 100 }
 101
 102 // === EXPORTS ===
 103 EXPORT(now);
 104 EXPORT(Time_CreateTimer);
 105 EXPORT(Time_RemoveTimer);
 106 EXPORT(Time_Delay);