1 /* Copyright (C) 1996-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <ctype.h>
19 #include <stdlib.h>
20 #include <netinet/ether.h>
21 #include <netinet/if_ether.h>
22 
23 
24 struct ether_addr *
ether_aton_r(const char * asc,struct ether_addr * addr)25 ether_aton_r (const char *asc, struct ether_addr *addr)
26 {
27   size_t cnt;
28 
29   for (cnt = 0; cnt < 6; ++cnt)
30     {
31       unsigned int number;
32       char ch;
33 
34       ch = _tolower (*asc++);
35       if ((ch < '0' || ch > '9') && (ch < 'a' || ch > 'f'))
36 	return NULL;
37       number = isdigit (ch) ? (ch - '0') : (ch - 'a' + 10);
38 
39       ch = _tolower (*asc);
40       if ((cnt < 5 && ch != ':') || (cnt == 5 && ch != '\0' && !isspace (ch)))
41 	{
42 	  ++asc;
43 	  if ((ch < '0' || ch > '9') && (ch < 'a' || ch > 'f'))
44 	    return NULL;
45 	  number <<= 4;
46 	  number += isdigit (ch) ? (ch - '0') : (ch - 'a' + 10);
47 
48 	  ch = *asc;
49 	  if (cnt < 5 && ch != ':')
50 	    return NULL;
51 	}
52 
53       /* Store result.  */
54       addr->ether_addr_octet[cnt] = (unsigned char) number;
55 
56       /* Skip ':'.  */
57       ++asc;
58     }
59 
60   return addr;
61 }
62 libc_hidden_def (ether_aton_r)
63