ut372: Break out character-pair decoding to a separate function.

diff --git a/src/dmm/ut372.c b/src/dmm/ut372.c
index b5e2c703f7682eaf132888aa4fb70362951d089f..2f8ed1fa3c7dcd3406b5243d54bb3c9accd52afc 100644 (file)
--- a/src/dmm/ut372.c
+++ b/src/dmm/ut372.c
@@ -23,13 +23,14 @@
  */
 
 #include <stdlib.h>
+#include <stdint.h>
 #include <math.h>
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
 
 #define LOG_PREFIX "ut372"
 
-char lookup[] = {
+uint8_t lookup[] = {
        0x7B,
        0x60,
        0x5E,
@@ -44,6 +45,23 @@ char lookup[] = {
 
 #define DECIMAL_POINT_MASK 0x80
 
+/* Decode a pair of characters into a byte. */
+static uint8_t decode_pair(const uint8_t *buf)
+{
+       unsigned int i;
+       char hex[3];
+
+       hex[2] = '\0';
+
+       for (i = 0; i < 2; i++) {
+               hex[i] = buf[i];
+               if (hex[i] > 0x39)
+                       hex[i] += 7;
+       }
+
+       return strtol(hex, NULL, 16);
+}
+
 SR_PRIV gboolean sr_ut372_packet_valid(const uint8_t *buf)
 {
        return (buf[25] == '\r' && buf[26] == '\n');
@@ -52,22 +70,16 @@ SR_PRIV gboolean sr_ut372_packet_valid(const uint8_t *buf)
 SR_PRIV int sr_ut372_parse(const uint8_t *buf, float *floatval,
                struct sr_datafeed_analog *analog, void *info)
 {
-       unsigned int i, j, segments, value, divisor;
-       char hex[3];
+       unsigned int i, j, value, divisor;
+       uint8_t segments;
 
        (void) info;
 
-       hex[2] = '\0';
        value = 0;
        divisor = 1;
 
        for (i = 0; i < 5; i++) {
-               for (j = 0; j < 2; j++) {
-                       hex[j] = buf[2*i + 1 + j];
-                       if (hex[j] > 0x39)
-                               hex[j] += 7;
-               }
-               segments = strtol(hex, NULL, 16);
+               segments = decode_pair(buf + 1 + 2*i);
                for (j = 0; j < ARRAY_SIZE(lookup); j++) {
                        if (lookup[j] == (segments & ~DECIMAL_POINT_MASK)) {
                                value += j * pow(10, i);