compat/inet_pton.c

   1 /*****************************************************************************
   2  * inet_pton.c: POSIX/IETF inet_pton() and inet_ntop() replacements
   3  *****************************************************************************
   4  * Copyright © 2011 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include <stdio.h>
  26 #include <errno.h>
  27
  28 #include <sys/types.h>
  29 #ifdef HAVE_SYS_SOCKET_H
  30 # include <sys/socket.h>
  31 #elif defined(_WIN32)
  32 # include <winsock2.h>
  33 # include <ws2tcpip.h>
  34 # undef EAFNOSUPPORT
  35 # define EAFNOSUPPORT WSAEAFNOSUPPORT
  36 #endif
  37
  38 int inet_pton (int af, const char *src, void *dst)
  39 {
  40     unsigned char *b = dst;
  41
  42     switch (af)
  43     {
  44         case AF_INET:
  45             return sscanf (src, "%hhu.%hhu.%hhu.%hhu",
  46                            b + 0, b + 1, b + 2, b + 3) == 4;
  47     }
  48     errno = EAFNOSUPPORT;
  49     return -1;
  50 }
  51
  52 const char *inet_ntop (int af, const void *src, char *dst, socklen_t len)
  53 {
  54     const unsigned char *b = src;
  55
  56     switch (af)
  57     {
  58         case AF_INET:
  59             if (snprintf (dst, len, "%hhu.%hhu.%hhu.%hhu",
  60                           b[0], b[1], b[2], b[3]) >= len)
  61             {
  62                 errno = ENOSPC;
  63                 return NULL;
  64             }
  65             return dst;
  66     }
  67     errno = EAFNOSUPPORT;
  68     return NULL;
  69 }