X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fstrutil.c;h=72378d4a2942d5dd7f411e35d41ffb7a01b9a183;hb=241c386a4f727faa7c8379ae9212661011aa50ae;hp=fc6c7580553555a8b76c7e1126e719ea38aa4220;hpb=2ea1fdf12113311cbe1a4316e9e2efe4d8ac40f0;p=libsigrok.git

diff --git a/src/strutil.c b/src/strutil.c
index fc6c7580..72378d4a 100644
--- a/src/strutil.c
+++ b/src/strutil.c
@@ -347,35 +347,53 @@ SR_API char *sr_samplerate_string(uint64_t samplerate)
 }
 
 /**
- * Convert a numeric frequency value to the "natural" string representation
- * of its period.
+ * Convert a numeric period value to the "natural" string representation
+ * of its period value.
  *
- * E.g. a value of 3000000 would be converted to "3 us", 20000 to "50 ms".
+ * The period is specified as a rational number's numerator and denominator.
  *
- * @param frequency The frequency in Hz.
+ * E.g. a pair of (1, 5) would be converted to "200 ms", (10, 100) to "100 ms".
  *
- * @return A newly allocated string representation of the frequency value,
+ * @param v_p The period numerator.
+ * @param v_q The period denominator.
+ *
+ * @return A newly allocated string representation of the period value,
  *         or NULL upon errors. The caller is responsible to g_free() the
  *         memory.
  *
- * @since 0.1.0
+ * @since 0.5.0
  */
-SR_API char *sr_period_string(uint64_t frequency)
+SR_API char *sr_period_string(uint64_t v_p, uint64_t v_q)
 {
+	double freq, v;
 	char *o;
-	int r;
+	int prec, r;
+
+	freq = 1 / ((double)v_p / v_q);
 
-	/* Allocate enough for a uint64_t as string + " ms". */
 	o = g_malloc0(30 + 1);
 
-	if (frequency >= SR_GHZ(1))
-		r = snprintf(o, 30, "%" PRIu64 " ns", frequency / 1000000000);
-	else if (frequency >= SR_MHZ(1))
-		r = snprintf(o, 30, "%" PRIu64 " us", frequency / 1000000);
-	else if (frequency >= SR_KHZ(1))
-		r = snprintf(o, 30, "%" PRIu64 " ms", frequency / 1000);
-	else
-		r = snprintf(o, 30, "%" PRIu64 " s", frequency);
+	if (freq > SR_GHZ(1)) {
+		v = (double)v_p / v_q * 1000000000000.0;
+		prec = ((v - (uint64_t)v) < FLT_MIN) ? 0 : 3;
+		r = snprintf(o, 30, "%.*f ps", prec, v);
+	} else if (freq > SR_MHZ(1)) {
+		v = (double)v_p / v_q * 1000000000.0;
+		prec = ((v - (uint64_t)v) < FLT_MIN) ? 0 : 3;
+		r = snprintf(o, 30, "%.*f ns", prec, v);
+	} else if (freq > SR_KHZ(1)) {
+		v = (double)v_p / v_q * 1000000.0;
+		prec = ((v - (uint64_t)v) < FLT_MIN) ? 0 : 3;
+		r = snprintf(o, 30, "%.*f us", prec, v);
+	} else if (freq > 1) {
+		v = (double)v_p / v_q * 1000.0;
+		prec = ((v - (uint64_t)v) < FLT_MIN) ? 0 : 3;
+		r = snprintf(o, 30, "%.*f ms", prec, v);
+	} else {
+		v = (double)v_p / v_q;
+		prec = ((v - (uint64_t)v) < FLT_MIN) ? 0 : 3;
+		r = snprintf(o, 30, "%.*f s", prec, v);
+	}
 
 	if (r < 0) {
 		/* Something went wrong... */