libc/socket/inet_addr.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2009  Tomas 'ZeXx86' Jedrzejek (zexx86@zexos.org)
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <arpa/inet.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26
  27 #define NET_IPV4_TO_ADDR(a, b, c, d) \
  28         (((unsigned)(d) << 24) | (((unsigned)(c) & 0xff) << 16) | (((unsigned)(b) & 0xff) << 8) | ((unsigned)(a) & 0xff))
  29
  30 in_addr_t inet_addr (const char *src)
  31 {
  32         if (!src)
  33                 return 0;
  34
  35         unsigned char a = 0;
  36         unsigned char b = 0;
  37         unsigned char c = 0;
  38         unsigned char d = 0;
  39
  40         unsigned g = 0;
  41         unsigned i = 0;
  42         unsigned y = strlen (src);
  43
  44         if (!y)
  45                 return 0;
  46
  47         char *str = (char *) malloc (sizeof (char) * (y + 1));
  48
  49         if (!str)
  50                 return 0;
  51
  52         memcpy (str, src, y);
  53         str[y] = '\0';
  54
  55         unsigned h[4];
  56
  57         while (i < y) {
  58                 if (str[i] == '.') {
  59                         str[i] = '\0';
  60                         h[g] = i+1;
  61                         g ++;
  62                 }
  63         }
  64
  65         if (g != 3) {
  66                 free (str);
  67                 return -1;
  68         }
  69
  70         a = atoi (str);
  71         b = atoi (str+h[0]);
  72         c = atoi (str+h[1]);
  73         d = atoi (str+h[2]);
  74
  75         free (str);
  76
  77         g = NET_IPV4_TO_ADDR (a, b, c, d);
  78
  79         return (in_addr_t) g;
  80 }
  81