static long
rtcread(Chan *c, void *buf, long n, vlong offset)
{
ulong t, ot;
if(c->qid.type & QTDIR)
return devdirread(c, buf, n, rtcdir, NRTC, devgen);
switch((ulong)c->qid.path){
case Qrtc:
qlock(&rtclock);
t = rtctime();
do{
ot = t;
t = rtctime(); /* make sure there's no skew */
}while(t != ot);
qunlock(&rtclock);
n = readnum(offset, buf, n, t, 12);
return n;
case Qnvram:
if(offset > NVREAD)
return 0;
if(n > NVREAD - offset)
n = NVREAD - offset;
qlock(&rtclock);
memmove(buf, nvr.ram+offset, n);
qunlock(&rtclock);
return n;
}
error(Egreg);
return 0; /* not reached */
}
static long
rtcread(Chan* c, void* buf, long n, vlong off)
{
ulong t;
ulong offset = off;
if(c->qid.type & QTDIR)
return devdirread(c, buf, n, rtcdir, nelem(rtcdir), devgen);
switch((ulong)c->qid.path){
case Qrtc:
t = rtctime();
n = readnum(offset, buf, n, t, 12);
return n;
}
error(Ebadarg);
return 0;
}
static long
rtcread(Chan* c, void* buf, long n, vlong off)
{
ulong t;
char *a, *start;
ulong offset = off;
if(c->qid.type & QTDIR)
return devdirread(c, buf, n, rtcdir, nelem(rtcdir), devgen);
switch((ulong)c->qid.path){
case Qrtc:
t = rtctime();
n = readnum(offset, buf, n, t, 12);
return n;
case Qnvram:
if(n == 0)
return 0;
if(n > Nvsize)
n = Nvsize;
a = start = smalloc(n);
ilock(&nvrtlock);
for(t = offset; t < offset + n; t++){
if(t >= Nvsize)
break;
outb(Paddr, Nvoff+t);
*a++ = inb(Pdata);
}
iunlock(&nvrtlock);
if(waserror()){
free(start);
nexterror();
}
memmove(buf, start, t - offset);
poperror();
free(start);
return t - offset;
}
error(Ebadarg);
return 0;
}