+#include <string.h>
+#include <math.h>
+
+extern struct sr_dev_driver uni_t_ut32x_driver_info;
+static struct sr_dev_driver *di = &uni_t_ut32x_driver_info;
+
+static float parse_temperature(unsigned char *buf)
+{
+ float temp;
+ int i;
+ gboolean negative;
+
+ negative = FALSE;
+ temp = 0.0;
+ for (i = 0; i < 4; i++) {
+ if (buf[i] == 0x3a)
+ continue;
+ if (buf[i] == 0x3b) {
+ if (negative) {
+ sr_dbg("Double negative sign!");
+ return NAN;
+ } else {
+ negative = TRUE;
+ continue;
+ }
+ }
+ if (buf[i] < 0x30 || buf[i] > 0x39) {
+ sr_dbg("Invalid digit '%.2x'!", buf[i]);
+ return NAN;
+ }
+ temp *= 10;
+ temp += (buf[i] - 0x30);
+ }
+ temp /= 10;
+ if (negative)
+ temp = -temp;
+
+ return temp;
+}
+
+static void process_packet(struct sr_dev_inst *sdi)
+{
+ struct dev_context *devc;
+ struct sr_datafeed_packet packet;
+ struct sr_datafeed_analog analog;
+ GString *spew;
+ float temp;
+ int i;
+ gboolean is_valid;
+
+ devc = sdi->priv;
+ sr_dbg("Received full 19-byte packet.");
+ if (sr_log_loglevel_get() >= SR_LOG_SPEW) {
+ spew = g_string_sized_new(60);
+ for (i = 0; i < devc->packet_len; i++)
+ g_string_append_printf(spew, "%.2x ", devc->packet[i]);
+ sr_spew("%s", spew->str);
+ g_string_free(spew, TRUE);
+ }
+
+ is_valid = TRUE;
+ if (devc->packet[1] == 0x3b && devc->packet[2] == 0x3b
+ && devc->packet[3] == 0x3b && devc->packet[4] == 0x3b)
+ /* No measurement: missing channel, empty storage location, ... */
+ is_valid = FALSE;
+
+ temp = parse_temperature(devc->packet + 1);
+ if (isnan(temp))
+ is_valid = FALSE;
+
+ if (is_valid) {
+ memset(&analog, 0, sizeof(struct sr_datafeed_analog));
+ analog.mq = SR_MQ_TEMPERATURE;
+ analog.mqflags = 0;
+ switch (devc->packet[5] - 0x30) {
+ case 1:
+ analog.unit = SR_UNIT_CELSIUS;
+ break;
+ case 2:
+ analog.unit = SR_UNIT_FAHRENHEIT;
+ break;
+ case 3:
+ analog.unit = SR_UNIT_KELVIN;
+ break;
+ default:
+ /* We can still pass on the measurement, whatever it is. */
+ sr_dbg("Unknown unit 0x%.2x.", devc->packet[5]);
+ }
+ switch (devc->packet[13] - 0x30) {
+ case 0:
+ /* Channel T1. */
+ analog.channels = g_slist_append(NULL, g_slist_nth_data(sdi->channels, 0));
+ break;
+ case 1:
+ /* Channel T2. */
+ analog.channels = g_slist_append(NULL, g_slist_nth_data(sdi->channels, 1));
+ break;
+ case 2:
+ case 3:
+ /* Channel T1-T2. */
+ analog.channels = g_slist_append(NULL, g_slist_nth_data(sdi->channels, 2));
+ analog.mqflags |= SR_MQFLAG_RELATIVE;
+ break;
+ default:
+ sr_err("Unknown channel 0x%.2x.", devc->packet[13]);
+ is_valid = FALSE;
+ }
+ if (is_valid) {
+ analog.num_samples = 1;
+ analog.data = &temp;
+ packet.type = SR_DF_ANALOG;
+ packet.payload = &analog;
+ sr_session_send(devc->cb_data, &packet);
+ g_slist_free(analog.channels);
+ }
+ }
+
+ /* We count packets even if the temperature was invalid. This way
+ * a sample limit on "Memory" data source still works: unused
+ * memory slots come through as "----" measurements. */
+ devc->num_samples++;
+ if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
+ sdi->driver->dev_acquisition_stop((struct sr_dev_inst *)sdi,
+ devc->cb_data);
+ }
+
+}
+
+SR_PRIV void uni_t_ut32x_receive_transfer(struct libusb_transfer *transfer)
+{
+ struct dev_context *devc;
+ struct sr_dev_inst *sdi;
+ int hid_payload_len, ret;
+
+ sdi = transfer->user_data;
+ devc = sdi->priv;
+ if (transfer->actual_length == 8) {
+ /* CH9325 encodes length in low nibble of first byte, with
+ * bytes 1-7 being the (padded) payload. */
+ hid_payload_len = transfer->buffer[0] & 0x0f;
+ memcpy(devc->packet + devc->packet_len, transfer->buffer + 1,
+ hid_payload_len);
+ devc->packet_len += hid_payload_len;
+ if (devc->packet_len >= 2
+ && devc->packet[devc->packet_len - 2] == 0x0d
+ && devc->packet[devc->packet_len - 1] == 0x0a) {
+ /* Got end of packet, but do we have a complete packet? */
+ if (devc->packet_len == 19)
+ process_packet(sdi);
+ /* Either way, done with it. */
+ devc->packet_len = 0;
+ } else if (devc->packet_len > 19) {
+ /* Guard against garbage from the device overrunning
+ * our packet buffer. */
+ sr_dbg("Buffer overrun!");
+ devc->packet_len = 0;
+ }
+ }
+
+ /* Get the next transfer (unless we're shutting down). */
+ if (sdi->status != SR_ST_STOPPING) {
+ if ((ret = libusb_submit_transfer(devc->xfer)) != 0) {
+ sr_dbg("Failed to resubmit transfer: %s", libusb_error_name(ret));
+ sdi->status = SR_ST_STOPPING;
+ libusb_free_transfer(devc->xfer);
+ }
+ } else
+ libusb_free_transfer(devc->xfer);
+
+}
+