diff --git a/include/libsigrok/proto.h b/include/libsigrok/proto.h
index dfce6aa2..0f4b9884 100644
--- a/include/libsigrok/proto.h
+++ b/include/libsigrok/proto.h
@@ -30,6 +30,8 @@
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);
/*--- backend.c -------------------------------------------------------------*/
diff --git a/src/analog.c b/src/analog.c
index 9def3ac8..ccf6d319 100644
--- a/src/analog.c
+++ b/src/analog.c
@@ -17,7 +17,10 @@
* along with this program. If not, see .
*/
+#include
+#include
#include
+#include
#include "libsigrok.h"
#include "libsigrok-internal.h"
@@ -98,3 +101,36 @@ 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 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_float_to_string(float value, int digits, char *outbuf,
+ int bufsize)
+{
+ int cnt, i;
+
+ /* This produces at least one too many digits */
+ snprintf(outbuf, bufsize, "%.*f", digits, value);
+ for (i = 0, cnt = 0; outbuf[i] && i < bufsize; i++) {
+ if (isdigit(outbuf[i++]))
+ cnt++;
+ if (cnt == digits) {
+ outbuf[i] = 0;
+ break;
+ }
+ }
+
+ return SR_OK;
+}
+