Add analog helper sr_analog_unit_to_string().

diff --git a/include/libsigrok/proto.h b/include/libsigrok/proto.h
index 0f4b98848914ab1f95e1848fc564a6e9a46f38e0..e69346057c10efea9068ca41203ad5b2890ef840 100644 (file)
--- a/include/libsigrok/proto.h
+++ b/include/libsigrok/proto.h
@@ -32,6 +32,8 @@ SR_API int sr_analog_to_float(const struct sr_datafeed_analog2 *analog,
                float *buf);
 SR_API int sr_analog_float_to_string(float value, int digits, char *outbuf,
                int bufsize);
+SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog2 *analog,
+               char *outbuf, int bufsize);
 
 /*--- backend.c -------------------------------------------------------------*/
 

diff --git a/src/analog.c b/src/analog.c
index ccf6d31934bf605cc4a300d989b83055f9ceaa7d..4fd6a6f9a4410d06d0152e789b31bf662680ee6c 100644 (file)
--- a/src/analog.c
+++ b/src/analog.c
@@ -26,6 +26,63 @@
 
 #define LOG_PREFIX "analog"
 
+struct unit_mq_string {
+       uint64_t value;
+       char *str;
+};
+
+static struct unit_mq_string unit_strings[] = {
+       { SR_UNIT_VOLT, "V" },
+       { SR_UNIT_AMPERE, "A" },
+       { SR_UNIT_OHM, "\xe2\x84\xa6" },
+       { SR_UNIT_FARAD, "F" },
+       { SR_UNIT_HENRY, "H" },
+       { SR_UNIT_KELVIN, "K" },
+       { SR_UNIT_CELSIUS, "\xc2\xb0""C" },
+       { SR_UNIT_FAHRENHEIT, "\xc2\xb0""F" },
+       { SR_UNIT_HERTZ, "Hz" },
+       { SR_UNIT_PERCENTAGE, "%" },
+       { SR_UNIT_SECOND, "s" },
+       { SR_UNIT_SIEMENS, "S" },
+       { SR_UNIT_DECIBEL_MW, "dBu" },
+       { SR_UNIT_DECIBEL_VOLT, "dBv" },
+       { SR_UNIT_DECIBEL_SPL, "dB" },
+       { SR_UNIT_CONCENTRATION, "ppm" },
+       { SR_UNIT_REVOLUTIONS_PER_MINUTE, "RPM" },
+       { SR_UNIT_VOLT_AMPERE, "VA" },
+       { SR_UNIT_WATT, "W" },
+       { SR_UNIT_WATT_HOUR, "Wh" },
+       { SR_UNIT_METER_SECOND, "m/s" },
+       { SR_UNIT_HECTOPASCAL, "hPa" },
+       { SR_UNIT_HUMIDITY_293K, "%rF" },
+       { SR_UNIT_DEGREE, "\xc2\xb0" },
+       ALL_ZERO
+};
+
+static struct unit_mq_string mq_strings[] = {
+       { SR_MQFLAG_SPL_FREQ_WEIGHT_A, "(A)" },
+       { SR_MQFLAG_SPL_FREQ_WEIGHT_C, "(C)" },
+       { SR_MQFLAG_SPL_FREQ_WEIGHT_Z, "(Z)" },
+       { SR_MQFLAG_SPL_FREQ_WEIGHT_FLAT, "(SPL)" },
+       { SR_MQFLAG_SPL_TIME_WEIGHT_S, " S" },
+       { SR_MQFLAG_SPL_TIME_WEIGHT_F, " F" },
+       { SR_MQFLAG_SPL_LAT, " LAT" },
+       /* Not a standard function for SLMs, so this is a made-up notation. */
+       { SR_MQFLAG_SPL_PCT_OVER_ALARM, "%oA" },
+       { SR_MQFLAG_AC, " AC" },
+       { SR_MQFLAG_DC, " DC" },
+       { SR_MQFLAG_RMS, " RMS" },
+       { SR_MQFLAG_DIODE, " DIODE" },
+       { SR_MQFLAG_HOLD, " HOLD" },
+       { SR_MQFLAG_MAX, " MAX" },
+       { SR_MQFLAG_MIN, " MIN" },
+       { SR_MQFLAG_AUTORANGE, " AUTO" },
+       { SR_MQFLAG_RELATIVE, " REL" },
+       { SR_MQFLAG_AVG, " AVG" },
+       { SR_MQFLAG_REFERENCE, " REF" },
+       ALL_ZERO
+};
+
 SR_PRIV int sr_analog_init(struct sr_datafeed_analog2 *analog,
                struct sr_analog_encoding *encoding,
                struct sr_analog_meaning *meaning,
@@ -134,3 +191,38 @@ SR_API int sr_analog_float_to_string(float value, int digits, char *outbuf,
        return SR_OK;
 }
 
+/*
+ * Convert the unit/MQ/MQ flags in the analog struct to a string.
+ *
+ * @param analog Struct containing the unit, MQ and MQ flags.
+ * @param outbuf Buffer in which the resulting string will be placed.
+ * @param bufsize Size of the buffer in bytes.
+ *
+ * @retval SR_OK
+ *
+ * @since 0.4.0
+ */
+SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog2 *analog,
+               char *outbuf, int bufsize)
+{
+       int len, i;
+
+       outbuf[0] = 0;
+       for (i = 0; unit_strings[i].value; i++) {
+               if (analog->meaning->unit == unit_strings[i].value) {
+                       strncpy(outbuf, unit_strings[i].str, bufsize);
+                       break;
+               }
+       }
+
+       /* More than one MQ flag may apply. */
+       for (i = 0; mq_strings[i].value; i++) {
+               if (analog->meaning->mqflags & mq_strings[i].value) {
+                       len = strlen(outbuf);
+                       strncat(outbuf + len, mq_strings[i].str, bufsize - len);
+               }
+       }
+
+       return SR_OK;
+}
+