From 784dc1cecb4c9343ce6215c41b331df5d2f729f0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nils=20O=2E=20Sel=C3=A5sdal?= <noselasd@fiane.dyndns.org>
Date: Fri, 6 Dec 2013 23:10:32 +0100
Subject: [PATCH] Teach uc_hex_decode to skip spaces

---
 include/ucore/string.h |  4 ++--
 src/hex.c              | 18 +++++++++++++++-
 test/test_hex.c        | 47 ++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 64 insertions(+), 5 deletions(-)

diff --git a/include/ucore/string.h b/include/ucore/string.h
index 5bcc0cb..3fb3b1c 100644
--- a/include/ucore/string.h
+++ b/include/ucore/string.h
@@ -20,8 +20,8 @@ extern "C" {
  */
 char* uc_hex_encode(const uint8_t *in, size_t len, char *out);
 
-/** Decode hex. Will stop at the first non-hex digit
- * (anything not 0-9,a-f or A-F)
+/** Decode hex. Will stop at the first non-convertible hex-digit
+ * spaces(' ','\t,'\r','\n') in input are skipped
  * Subtract the return value from the passed in @out to find
  * the length of the converted data
  *
diff --git a/src/hex.c b/src/hex.c
index bf9a04d..e361856 100644
--- a/src/hex.c
+++ b/src/hex.c
@@ -1,4 +1,5 @@
 #include <stdint.h>
+#include <ctype.h>
 #include <stddef.h>
 #include <string.h>
 #include "ucore/string.h"
@@ -79,14 +80,29 @@ uc_hex_decode(const char *in, size_t maxlen,uint8_t *out)
 {
     size_t i, t;
 
-    for (t = 0,i = 0; i + 1 < maxlen && in[i] && in[i + 1]; i+=2 , ++t) {
+    for (t = 0,i = 0; i + 1 < maxlen ;) {
         int hn, ln;
+        if (!(in[i] && in[i + 1])) {
+            break;
+        }
+
+        if (in[i] == ' '  ||
+            in[i] == '\t' ||
+            in[i] == '\r' ||
+            in[i] == '\n') {
+
+            i++;
+            continue;
+        }
+
         hn = char_to_bin(in[i]);
         ln = char_to_bin(in[i + 1]);
         if (hn == -1 || ln == -1)
             return NULL;
 
         out[t] = (hn << 4 ) | ln;
+        i += 2;
+        t++;
     }
 
     return &out[t];
diff --git a/test/test_hex.c b/test/test_hex.c
index 212e0c8..1c6fa2a 100644
--- a/test/test_hex.c
+++ b/test/test_hex.c
@@ -87,7 +87,7 @@ END_TEST
 
 START_TEST (test_uc_hex_decode_empty_string)
     char hex[] = "";
-    uint8_t binary[4] = {0x11, 0x11, 0x11};
+    uint8_t binary[] = {0x11, 0x11, 0x11};
     uint8_t *res;
 
     res = uc_hex_decode(hex, 2, binary);
@@ -95,7 +95,47 @@ START_TEST (test_uc_hex_decode_empty_string)
     fail_if(binary[0] != 0x11);
     fail_if(binary[1] != 0x11);
     fail_if(binary[2] != 0x11);
-    fail_if(res != binary);
+    fail_if(res != binary, "length %zu\n", res - binary);
+
+END_TEST
+START_TEST (test_uc_hex_decode_spaces)
+    char hex[] = " 11 1213";
+    uint8_t binary[3];
+    uint8_t *res;
+
+    res = uc_hex_decode(hex, strlen(hex), binary);
+
+    fail_if(binary[0] != 0x11);
+    fail_if(binary[1] != 0x12);
+    fail_if(binary[2] != 0x13);
+    fail_if(res != binary+3, "length %zu\n", res - binary);
+
+END_TEST
+
+START_TEST (test_uc_hex_decode_spaces2)
+    char hex[] = "1112  13\r\n";
+    uint8_t binary[3];
+    uint8_t *res;
+
+    res = uc_hex_decode(hex, strlen(hex), binary);
+
+    fail_if(binary[0] != 0x11);
+    fail_if(binary[1] != 0x12);
+    fail_if(binary[2] != 0x13);
+    fail_if(res != binary+3, "length %zu\n", res - binary);
+
+END_TEST
+
+START_TEST (test_uc_hex_decode_spaces_empty)
+    char hex[] = " \r\n  ";
+    uint8_t binary[] = {0x11,0x12};
+    uint8_t *res;
+
+    res = uc_hex_decode(hex, strlen(hex), binary);
+
+    fail_if(binary[0] != 0x11);
+    fail_if(binary[1] != 0x12);
+    fail_if(res != binary, "length %zu\n", res - binary);
 
 END_TEST
 
@@ -194,6 +234,9 @@ Suite *hex_suite(void)
     tcase_add_test(tc, test_uc_hex_decode_1);
     tcase_add_test(tc, test_uc_hex_decode_2);
     tcase_add_test(tc, test_uc_hex_decode_zero_length);
+    tcase_add_test(tc, test_uc_hex_decode_spaces);
+    tcase_add_test(tc, test_uc_hex_decode_spaces2);
+    tcase_add_test(tc, test_uc_hex_decode_spaces_empty);
     tcase_add_test(tc, test_uc_hex_decode_odd_length);
     tcase_add_test(tc, test_uc_hex_decode_invalid);
     tcase_add_test(tc, test_uc_hex_decode_empty_string);