ref: 2149600d129944f60cbc858bc669193af0523409
dir: /sys/src/cmd/rio/time.c/
#include <u.h> #include <libc.h> #include <draw.h> #include <thread.h> #include <cursor.h> #include <mouse.h> #include <keyboard.h> #include <frame.h> #include <fcall.h> #include "dat.h" #include "fns.h" static Channel* ctimer; /* chan(Timer*)[100] */ static Timer *timer; static uint msec(void) { return nsec()/1000000; } void timerstop(Timer *t) { t->next = timer; timer = t; } void timercancel(Timer *t) { t->cancel = TRUE; } static void timerproc(void*) { int i, nt, na, dt, del; Timer **t, *x; uint old, new; rfork(RFFDG); threadsetname("TIMERPROC"); t = nil; na = 0; nt = 0; old = msec(); for(;;){ sleep(1); /* will sleep minimum incr */ new = msec(); dt = new-old; old = new; if(dt < 0) /* timer wrapped; go around, losing a tick */ continue; for(i=0; i<nt; i++){ x = t[i]; x->dt -= dt; del = 0; if(x->cancel){ timerstop(x); del = 1; }else if(x->dt <= 0){ /* * avoid possible deadlock if client is * now sending on ctimer */ if(nbsendul(x->c, 0) > 0) del = 1; } if(del){ memmove(&t[i], &t[i+1], (nt-i-1)*sizeof t[0]); --nt; --i; } } if(nt == 0){ x = recvp(ctimer); gotit: if(nt == na){ na += 10; t = realloc(t, na*sizeof(Timer*)); if(t == nil) abort(); } t[nt++] = x; old = msec(); } if(nbrecv(ctimer, &x) > 0) goto gotit; } } void timerinit(void) { ctimer = chancreate(sizeof(Timer*), 100); proccreate(timerproc, nil, STACK); } /* * timeralloc() and timerfree() don't lock, so can only be * called from the main proc. */ Timer* timerstart(int dt) { Timer *t; t = timer; if(t) timer = timer->next; else{ t = emalloc(sizeof(Timer)); t->c = chancreate(sizeof(int), 0); } t->next = nil; t->dt = dt; t->cancel = FALSE; sendp(ctimer, t); return t; }