Contiki-NG
hexconv.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2016, SICS, Swedish ICT AB.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  * notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  * notice, this list of conditions and the following disclaimer in the
12  * documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the Institute nor the names of its contributors
14  * may be used to endorse or promote products derived from this software
15  * without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /**
31  * \file
32  * A small util to convert between bytes and hex string
33  * \author
34  * Niclas Finne <nfi@sics.se>
35  */
36 
37 #include "lib/hexconv.h"
38 #include "sys/cc.h"
39 #include <stdio.h>
40 /*---------------------------------------------------------------------------*/
41 static CC_INLINE int
42 fromhex(char c)
43 {
44  if(c >= '0' && c <= '9') {
45  return c - '0';
46  }
47  if(c >= 'a' && c <= 'f') {
48  return c - 'a' + 10;
49  }
50  if(c >= 'A' && c <= 'F') {
51  return c - 'A' + 10;
52  }
53  return -1;
54 }
55 /*---------------------------------------------------------------------------*/
56 int
57 hexconv_hexlify(const uint8_t *data, int data_len, char *text, int text_size)
58 {
59  static const char *HEX = "01234567890abcdef";
60  int i, p;
61 
62  for(i = 0, p = 0; p + 1 < text_size && i < data_len; i++) {
63  text[p++] = HEX[(data[i] >> 4) & 0xf];
64  text[p++] = HEX[data[i] & 0xf];
65  }
66  return p;
67 }
68 /*---------------------------------------------------------------------------*/
69 int
70 hexconv_unhexlify(const char *text, int text_len, uint8_t *buf, int buf_size)
71 {
72  int i, p, c1, c2;
73 
74  if((text_len & 1) != 0) {
75  /* The string must be of an even length */
76  return -1;
77  }
78 
79  for(i = 0, p = 0; p < buf_size && i + 1 < text_len; i += 2, p++) {
80  c1 = fromhex(text[i]);
81  c2 = fromhex(text[i + 1]);
82  if(c1 < 0 || c2 < 0) {
83  return -1;
84  }
85  buf[p] = ((c1 << 4) & 0xf0) + (c2 & 0xf);
86  }
87  return p;
88 }
89 /*---------------------------------------------------------------------------*/
90 void
91 hexconv_print(const uint8_t *data, int data_len)
92 {
93  int i;
94  for(i = 0; i < data_len; i++) {
95  printf("%02x", data[i]);
96  }
97 }
98 /*---------------------------------------------------------------------------*/
A small util to convert between bytes and hex string
Default definitions of C compiler quirk work-arounds.