Only build hardware drivers if they're enabled.

[libsigrok.git] / output / common.c

diff --git a/output/common.c b/output/common.c
index 1fc5df7d3517f3ce18d0b844c775bf438c6069cb..ad4720f75c4e30382ed38b15c7600de47407d744 100644 (file)
--- a/output/common.c
+++ b/output/common.c
@@ -58,3 +58,42 @@ char *sigrok_samplerate_string(uint64_t samplerate)
 
        return o;
 }
+
+
+/**
+ * Convert a numeric samplerate value to the "natural" string representation
+ * of its period.
+ *
+ * E.g. a value of 3000000 would be converted to "3 µs", 20000 to "50 ms".
+ *
+ * @param frequency The frequency in Hz.
+ * @return A malloc()ed string representation of the frequency value,
+ *         or NULL upon errors. The caller is responsible to free() the memory.
+ */
+char *sigrok_period_string(uint64_t frequency)
+{
+       char *o;
+       int r;
+
+       o = malloc(30 + 1); /* Enough for a uint64_t as string + " ms". */
+       if (o == NULL)
+               return NULL;
+
+       if (frequency >= GHZ(1))
+               r = snprintf(o, 30, "%" PRIu64 " ns", frequency / 1000000000);
+       else if (frequency >= MHZ(1))
+               r = snprintf(o, 30, "%" PRIu64 " µs", frequency / 1000000);
+       else if (frequency >= KHZ(1))
+               r = snprintf(o, 30, "%" PRIu64 " ms", frequency / 1000);
+       else
+               r = snprintf(o, 30, "%" PRIu64 " s", frequency);
+
+       if (r < 0) {
+               /* Something went wrong... */
+               free(o);
+               return NULL;
+       }
+
+       return o;
+}
+