From 55d39b8625164c13b5ad527e5b441b9d928a11e7 Mon Sep 17 00:00:00 2001
From: Dimitri Lozeve <dimitri@lozeve.com>
Date: Tue, 2 Jun 2020 21:36:42 +0200
Subject: [PATCH] Refactor hex_to_bytes

---
 utils.c | 16 +++++++++-------
 utils.h |  1 +
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/utils.c b/utils.c
index eb0f342..0fbf42e 100644
--- a/utils.c
+++ b/utils.c
@@ -2,15 +2,17 @@
 #include <ctype.h>
 #include <string.h>
 
+unsigned char hex_to_byte(const char c) {
+  if (isdigit(c)) {
+    return c - '0';
+  }
+  return 10 + c - 'a';
+}
+
 size_t hex_to_bytes(unsigned char *out, const char hex[static 1]) {
   for (size_t i = 0; i < strlen(hex); ++i) {
     char c = tolower(hex[i]);
-    unsigned char value;
-    if (isdigit(c)) {
-      value = c - '0';
-    } else {
-      value = 10 + c - 'a';
-    }
+    unsigned char value = hex_to_byte(c);
     if (i % 2 == 0) {
       value <<= 4;
     }
@@ -20,7 +22,7 @@ size_t hex_to_bytes(unsigned char *out, const char hex[static 1]) {
 }
 
 unsigned char *bytes_to_base64(unsigned char *out,
-                                const unsigned char in[static 1], size_t len) {
+                               const unsigned char in[static 1], size_t len) {
   static const unsigned char base64_table[65] =
       "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
diff --git a/utils.h b/utils.h
index 29bb13a..2f3f1cf 100644
--- a/utils.h
+++ b/utils.h
@@ -3,6 +3,7 @@
 
 #include <stdlib.h>
 
+unsigned char hex_to_byte(const char c);
 size_t hex_to_bytes(unsigned char *out, const char hex[static 1]);
 unsigned char *bytes_to_base64(unsigned char *out,
                                const unsigned char in[static 1], size_t len);