Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <draw.h>
#include <memdraw.h>
#include <thread.h>
#include <cursor.h>
#include <mouse.h>
#include <keyboard.h>
#include <frame.h>
#include <plumb.h>
#include <html.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;

        threadsetname("timerproc");
        rfork(RFFDG);
        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 = FALSE;
                        if(x->cancel){
                                timerstop(x);
                                del = TRUE;
                        }else if(x->dt <= 0){
                                /*
                                 * avoid possible deadlock if client is
                                 * now sending on ctimer
                                 */
                                if(nbsendul(x->c, 0) > 0)
                                        del = TRUE;
                        }
                        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 = erealloc(t, na*sizeof(Timer*));
                        }
                        t[nt++] = x;
                        old = msec();
                }
                if(nbrecv(ctimer, &x) > 0)
                        goto gotit;
        }
}

void
timerinit(void)
{
        ctimer = chancreate(sizeof(Timer*), 100);
        proccreate(timerproc, nil, STACK);
}

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;
}