glibc/inet/ether_aton_r.c

64 lines
1.8 KiB
C

/* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <ctype.h>
#include <stdlib.h>
#include <netinet/ether.h>
#include <netinet/if_ether.h>
struct ether_addr *
ether_aton_r (const char *asc, struct ether_addr *addr)
{
size_t cnt;
for (cnt = 0; cnt < 6; ++cnt)
{
unsigned int number;
char ch;
ch = tolower (*asc++);
if ((ch < '0' || ch > '9') && (ch < 'a' || ch > 'f'))
return NULL;
number = isdigit (ch) ? (ch - '0') : (ch - 'a' + 10);
ch = tolower (*asc);
if ((cnt < 5 && ch != ':') || (cnt == 5 && ch != '\0' && !isspace (ch)))
{
++asc;
if ((ch < '0' || ch > '9') && (ch < 'a' || ch > 'f'))
return NULL;
number <<= 4;
number += isdigit (ch) ? (ch - '0') : (ch - 'a' + 10);
ch = *asc;
if (cnt < 5 && ch != ':')
return NULL;
}
/* Store result. */
addr->ether_addr_octet[cnt] = (unsigned char) number;
/* Skip ':'. */
++asc;
}
return addr;
}