X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fanalog.c;h=da1560cd6702b91b66ae010b8263e84b30cebbcb;hb=c01bf34ca264b268fee2e71ab918c71d28dc3018;hp=61f1f733aaa8bdc7bd9433d42c4cc5ff7df5429f;hpb=6ec6c43b4738dbc7091f4a49a4ec80ea6102cb52;p=libsigrok.git

diff --git a/src/analog.c b/src/analog.c
index 61f1f733..da1560cd 100644
--- a/src/analog.c
+++ b/src/analog.c
@@ -45,7 +45,7 @@
 
 struct unit_mq_string {
 	uint64_t value;
-	char *str;
+	const char *str;
 };
 
 /* Please use the same order as in enum sr_unit (libsigrok.h). */
@@ -114,10 +114,11 @@ static struct unit_mq_string mq_strings[] = {
 	{ SR_MQFLAG_AVG, " AVG" },
 	{ SR_MQFLAG_REFERENCE, " REF" },
 	{ SR_MQFLAG_UNSTABLE, " UNSTABLE" },
+	{ SR_MQFLAG_FOUR_WIRE, " 4-WIRE" },
 	ALL_ZERO
 };
 
-SR_PRIV int sr_analog_init(struct sr_datafeed_analog2 *analog,
+SR_PRIV int sr_analog_init(struct sr_datafeed_analog *analog,
 		struct sr_analog_encoding *encoding,
 		struct sr_analog_meaning *meaning,
 		struct sr_analog_spec *spec,
@@ -151,39 +152,137 @@ SR_PRIV int sr_analog_init(struct sr_datafeed_analog2 *analog,
 	return SR_OK;
 }
 
-SR_API int sr_analog_to_float(const struct sr_datafeed_analog2 *analog,
+/**
+ * Convert an analog datafeed payload to an array of floats.
+ *
+ * @param[in] analog The analog payload to convert. Must not be NULL.
+ *                   analog->data, analog->meaning, and analog->encoding
+ *                   must not be NULL.
+ * @param[out] outbuf Memory where to store the result. Must not be NULL.
+ *
+ * Sufficient memory for outbuf must have been pre-allocated by the caller,
+ * who is also responsible for freeing it when no longer needed.
+ *
+ * @retval SR_OK Success.
+ * @retval SR_ERR Unsupported encoding.
+ * @retval SR_ERR_ARG Invalid argument.
+ *
+ * @since 0.4.0
+ */
+SR_API int sr_analog_to_float(const struct sr_datafeed_analog *analog,
 		float *outbuf)
 {
 	float offset;
-	unsigned int b, i;
+	unsigned int b, i, count;
 	gboolean bigendian;
 
+	if (!analog || !(analog->data) || !(analog->meaning)
+			|| !(analog->encoding) || !outbuf)
+		return SR_ERR_ARG;
+
+	count = analog->num_samples * g_slist_length(analog->meaning->channels);
+
 #ifdef WORDS_BIGENDIAN
 	bigendian = TRUE;
 #else
 	bigendian = FALSE;
 #endif
 	if (!analog->encoding->is_float) {
-		/* TODO */
-		sr_err("Only floating-point encoding supported so far.");
-		return SR_ERR;
+		float offset = analog->encoding->offset.p / (float)analog->encoding->offset.q;
+		float scale = analog->encoding->scale.p / (float)analog->encoding->scale.q;
+		gboolean is_signed = analog->encoding->is_signed;
+		gboolean is_bigendian = analog->encoding->is_bigendian;
+		int8_t *data8 = (int8_t *)(analog->data);
+		int16_t *data16 = (int16_t *)(analog->data);
+		int32_t *data32 = (int32_t *)(analog->data);
+
+		switch (analog->encoding->unitsize) {
+		case 1:
+			if (is_signed) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * data8[i];
+					outbuf[i] += offset;
+				}
+			} else {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * R8(data8 + i);
+					outbuf[i] += offset;
+				}
+			}
+			break;
+		case 2:
+			if (is_signed && is_bigendian) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RB16S(&data16[i]);
+					outbuf[i] += offset;
+				}
+			} else if (is_bigendian) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RB16(&data16[i]);
+					outbuf[i] += offset;
+				}
+			} else if (is_signed) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RL16S(&data16[i]);
+					outbuf[i] += offset;
+				}
+			} else {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RL16(&data16[i]);
+					outbuf[i] += offset;
+				}
+			}
+			break;
+		case 4:
+			if (is_signed && is_bigendian) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RB32S(&data32[i]);
+					outbuf[i] += offset;
+				}
+			} else if (is_bigendian) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RB32(&data32[i]);
+					outbuf[i] += offset;
+				}
+			} else if (is_signed) {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RL32S(&data32[i]);
+					outbuf[i] += offset;
+				}
+			} else {
+				for (unsigned int i = 0; i < count; i++) {
+					outbuf[i] = scale * RL32(&data32[i]);
+					outbuf[i] += offset;
+				}
+			}
+			break;
+		default:
+			sr_err("Unsupported unit size '%d' for analog-to-float conversion.",
+				analog->encoding->unitsize);
+			return SR_ERR;
+		}
+		return SR_OK;
 	}
 
 	if (analog->encoding->unitsize == sizeof(float)
 			&& analog->encoding->is_bigendian == bigendian
-			&& (analog->encoding->scale.p == analog->encoding->scale.q)
+			&& analog->encoding->scale.p == 1
+			&& analog->encoding->scale.q == 1
 			&& analog->encoding->offset.p / (float)analog->encoding->offset.q == 0) {
 		/* The data is already in the right format. */
-		memcpy(outbuf, analog->data, analog->num_samples * sizeof(float));
+		memcpy(outbuf, analog->data, count * sizeof(float));
 	} else {
-		for (i = 0; i < analog->num_samples; i += analog->encoding->unitsize) {
+		for (i = 0; i < count; i += analog->encoding->unitsize) {
 			for (b = 0; b < analog->encoding->unitsize; b++) {
 				if (analog->encoding->is_bigendian == bigendian)
-					outbuf[i + b] = ((float *)analog->data)[i * analog->encoding->unitsize + b];
+					((uint8_t *)outbuf)[i + b] =
+						((uint8_t *)analog->data)[i * analog->encoding->unitsize + b];
 				else
-					outbuf[i + (analog->encoding->unitsize - b)] = ((float *)analog->data)[i * analog->encoding->unitsize + b];
+					((uint8_t *)outbuf)[i + (analog->encoding->unitsize - b)] =
+						((uint8_t *)analog->data)[i * analog->encoding->unitsize + b];
 			}
-			if (analog->encoding->scale.p != analog->encoding->scale.q)
+			if (analog->encoding->scale.p != 1
+					|| analog->encoding->scale.q != 1)
 				outbuf[i] = (outbuf[i] * analog->encoding->scale.p) / analog->encoding->scale.q;
 			offset = ((float)analog->encoding->offset.p / (float)analog->encoding->offset.q);
 			outbuf[i] += offset;
@@ -193,57 +292,31 @@ SR_API int sr_analog_to_float(const struct sr_datafeed_analog2 *analog,
 	return SR_OK;
 }
 
-/*
- * Convert a floating point value to a string, limited to the given
- * number of decimal digits.
- *
- * @param value The value to convert.
- * @param digits Number of digits after the decimal point to print.
- * @param result Pointer to store result.
- *
- * The string is allocated by the function and must be freed by the caller
- * after use by calling g_free().
- *
- * @retval SR_OK
- *
- * @since 0.4.0
- */
-SR_API int sr_analog_float_to_string(float value, int digits, char **result)
-{
-	int cnt, i;
-
-	/* This produces at least one too many digits */
-	*result = g_strdup_printf("%.*f", digits, value);
-	for (i = 0, cnt = 0; (*result)[i]; i++) {
-		if (isdigit((*result)[i++]))
-			cnt++;
-		if (cnt == digits) {
-			(*result)[i] = 0;
-			break;
-		}
-	}
-
-	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 result Pointer to store result.
+ * @param[in] analog Struct containing the unit, MQ and MQ flags.
+ *                   Must not be NULL. analog->meaning must not be NULL.
+ * @param[out] result Pointer to store result. Must not be NULL.
  *
  * The string is allocated by the function and must be freed by the caller
  * after use by calling g_free().
  *
- * @retval SR_OK
+ * @retval SR_OK Success.
+ * @retval SR_ERR_ARG Invalid argument.
  *
  * @since 0.4.0
  */
-SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog2 *analog,
+SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog *analog,
 		char **result)
 {
 	int i;
-	GString *buf = g_string_new(NULL);
+	GString *buf;
+
+	if (!analog || !(analog->meaning) || !result)
+		return SR_ERR_ARG;
+
+	buf = g_string_new(NULL);
 
 	for (i = 0; unit_strings[i].value; i++) {
 		if (analog->meaning->unit == unit_strings[i].value) {
@@ -263,14 +336,20 @@ SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog2 *analog,
 	return SR_OK;
 }
 
-/*
+/**
  * Set sr_rational r to the given value.
  *
- * @param p Numerator
- * @param q Denominator
+ * @param[out] r Rational number struct to set. Must not be NULL.
+ * @param[in] p Numerator.
+ * @param[in] q Denominator.
+ *
+ * @since 0.4.0
  */
-SR_API void sr_rational_set(struct sr_rational *r, uint64_t p, uint64_t q)
+SR_API void sr_rational_set(struct sr_rational *r, int64_t p, uint64_t q)
 {
+	if (!r)
+		return;
+
 	r->p = p;
 	r->q = q;
 }