sys/src/cmd/abaco/time.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <draw.h>
   4 #include <memdraw.h>
   5 #include <thread.h>
   6 #include <cursor.h>
   7 #include <mouse.h>
   8 #include <keyboard.h>
   9 #include <frame.h>
  10 #include <plumb.h>
  11 #include <html.h>
  12 #include "dat.h"
  13 #include "fns.h"
  14
  15 static Channel* ctimer; /* chan(Timer*)[100] */
  16 static Timer *timer;
  17
  18 static
  19 uint
  20 msec(void)
  21 {
  22         return nsec()/1000000;
  23 }
  24
  25 void
  26 timerstop(Timer *t)
  27 {
  28         t->next = timer;
  29         timer = t;
  30 }
  31
  32 void
  33 timercancel(Timer *t)
  34 {
  35         t->cancel = TRUE;
  36 }
  37
  38 static
  39 void
  40 timerproc(void*)
  41 {
  42         int i, nt, na, dt, del;
  43         Timer **t, *x;
  44         uint old, new;
  45
  46         threadsetname("timerproc");
  47         rfork(RFFDG);
  48         t = nil;
  49         na = 0;
  50         nt = 0;
  51         old = msec();
  52         for(;;){
  53                 sleep(1);       /* will sleep minimum incr */
  54                 new = msec();
  55                 dt = new-old;
  56                 old = new;
  57                 if(dt < 0)      /* timer wrapped; go around, losing a tick */
  58                         continue;
  59                 for(i=0; i<nt; i++){
  60                         x = t[i];
  61                         x->dt -= dt;
  62                         del = FALSE;
  63                         if(x->cancel){
  64                                 timerstop(x);
  65                                 del = TRUE;
  66                         }else if(x->dt <= 0){
  67                                 /*
  68                                  * avoid possible deadlock if client is
  69                                  * now sending on ctimer
  70                                  */
  71                                 if(nbsendul(x->c, 0) > 0)
  72                                         del = TRUE;
  73                         }
  74                         if(del){
  75                                 memmove(&t[i], &t[i+1], (nt-i-1)*sizeof t[0]);
  76                                 --nt;
  77                                 --i;
  78                         }
  79                 }
  80                 if(nt == 0){
  81                         x = recvp(ctimer);
  82         gotit:
  83                         if(nt == na){
  84                                 na += 10;
  85                                 t = erealloc(t, na*sizeof(Timer*));
  86                         }
  87                         t[nt++] = x;
  88                         old = msec();
  89                 }
  90                 if(nbrecv(ctimer, &x) > 0)
  91                         goto gotit;
  92         }
  93 }
  94
  95 void
  96 timerinit(void)
  97 {
  98         ctimer = chancreate(sizeof(Timer*), 100);
  99         proccreate(timerproc, nil, STACK);
 100 }
 101
 102 Timer*
 103 timerstart(int dt)
 104 {
 105         Timer *t;
 106
 107         t = timer;
 108         if(t)
 109                 timer = timer->next;
 110         else{
 111                 t = emalloc(sizeof(Timer));
 112                 t->c = chancreate(sizeof(int), 0);
 113         }
 114         t->next = nil;
 115         t->dt = dt;
 116         t->cancel = FALSE;
 117         sendp(ctimer, t);
 118         return t;
 119 }