void GEaddDevice(pGEDevDesc gdd)
{
int i;
Rboolean appnd;
SEXP s, t;
pGEDevDesc oldd;
PROTECT(s = getSymbolValue(R_DevicesSymbol));
if (!NoDevices()) {
oldd = GEcurrentDevice();
if(oldd->dev->deactivate) oldd->dev->deactivate(oldd->dev);
}
/* find empty slot for new descriptor */
i = 1;
if (CDR(s) == R_NilValue)
appnd = TRUE;
else {
s = CDR(s);
appnd = FALSE;
}
while (R_Devices[i] != NULL) {
i++;
if (CDR(s) == R_NilValue)
appnd = TRUE;
else
s = CDR(s);
}
R_CurrentDevice = i;
R_NumDevices++;
R_Devices[i] = gdd;
active[i] = TRUE;
GEregisterWithDevice(gdd);
if(gdd->dev->activate) gdd->dev->activate(gdd->dev);
/* maintain .Devices (.Device has already been set) */
t = PROTECT(duplicate(getSymbolValue(R_DeviceSymbol)));
if (appnd)
SETCDR(s, CONS(t, R_NilValue));
else
SETCAR(s, t);
UNPROTECT(2);
/* In case a device driver did not call R_CheckDeviceAvailable
before starting its allocation, we complete the allocation and
then call killDevice here. This ensures that the device gets a
chance to deallocate its resources and the current active
device is restored to a sane value. */
if (i == R_MaxDevices - 1) {
killDevice(i);
error(_("too many open devices"));
}
}
SEXP devoff(SEXP args)
{
checkArity_length;
killDevice(INTEGER(CAR(args))[0] - 1);
return R_NilValue;
}
