// Get a list of gains supported by the tuner.
//
// A NULL second parameter requests the gain count.
// Gain values are in tenths of dB, e.g. 115 means 11.5 dB.
//
// int rtlsdr_get_tuner_gains(rtlsdr_dev_t *dev, int *gains);
// rtlsdr_get_tuner_gains returns <= 0 on error or the number of available gain
func (c *Context) GetTunerGains() (gains []int, err int) {
// count := int(C.rtlsdr_get_tuner_gains((*C.rtlsdr_dev_t)(c.dev), nil))
count := int(C.rtlsdr_get_tuner_gains((*C.rtlsdr_dev_t)(c.dev),
(*C.int)(unsafe.Pointer(uintptr(0)))))
if count < 0 {
err = count
return
} else if count == 0 {
return
}
gains = make([]int, count)
C.rtlsdr_get_tuner_gains((*C.rtlsdr_dev_t)(c.dev),
(*C.int)(unsafe.Pointer(&gains[0])))
return
}
// GetTunerGains returns a list of supported tuner gains.
// Values are in tenths of dB, e.g. 115 means 11.5 dB.
func (dev *Context) GetTunerGains() (gainsTenthsDb []int, err error) {
// count := int(C.rtlsdr_get_tuner_gains((*C.rtlsdr_dev_t)(c.dev), nil))
i := int(C.rtlsdr_get_tuner_gains((*C.rtlsdr_dev_t)(dev),
(*C.int)(unsafe.Pointer(nil))))
if i <= 0 {
return gainsTenthsDb, libError(i)
}
buf := make([]C.int, i)
i = int(C.rtlsdr_get_tuner_gains((*C.rtlsdr_dev_t)(dev),
(*C.int)(unsafe.Pointer(&buf[0]))))
if i <= 0 {
return gainsTenthsDb, libError(i)
}
gainsTenthsDb = make([]int, i)
for ii := 0; ii < i; ii++ {
gainsTenthsDb[ii] = int(buf[ii])
}
return gainsTenthsDb, nil
}
// GetTunerGains retrieves and stores the list of available tuner gain options
func (dev *Radio) GetTunerGains() ([]int, error) {
dev.lock.Lock()
defer dev.lock.Unlock()
// The underlying rtlsdr call returns a pointer to an array of ints. The first
// call figures out how big that array will be
retval := C.rtlsdr_get_tuner_gains(dev.devptr, nil)
if retval <= 0 {
return nil, fmt.Errorf("rtlsdr_get_tuner_gains returned error value: %d", retval)
}
cGains := make([]C.int, 100)
retval = C.rtlsdr_get_tuner_gains(dev.devptr, (*C.int)(unsafe.Pointer(&cGains[0])))
if retval <= 0 {
return nil, fmt.Errorf("rtlsdr_get_tuner_gains returned error value: %d", retval)
}
for i := 0; i < int(retval); i++ {
dev.GainOptions = append(dev.GainOptions, int(cGains[i]))
}
return dev.GainOptions, nil
}
