lib/inet_proto.c

   1 /*
   2  * inet_proto.c
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <fcntl.h>
  17 #include <sys/socket.h>
  18 #include <netinet/in.h>
  19 #include <netdb.h>
  20 #include <string.h>
  21
  22 #include "rt_names.h"
  23 #include "utils.h"
  24
  25 const char *inet_proto_n2a(int proto, char *buf, int len)
  26 {
  27         static char *ncache;
  28         static int icache = -1;
  29         struct protoent *pe;
  30
  31         if (proto == icache)
  32                 return ncache;
  33
  34         pe = getprotobynumber(proto);
  35         if (pe) {
  36                 if (icache != -1)
  37                         free(ncache);
  38                 icache = proto;
  39                 ncache = strdup(pe->p_name);
  40                 strlcpy(buf, pe->p_name, len);
  41                 return buf;
  42         }
  43         snprintf(buf, len, "ipproto-%d", proto);
  44         return buf;
  45 }
  46
  47 int inet_proto_a2n(const char *buf)
  48 {
  49         static char *ncache;
  50         static int icache = -1;
  51         struct protoent *pe;
  52         __u8 ret;
  53
  54         if (icache != -1 && strcmp(ncache, buf) == 0)
  55                 return icache;
  56
  57         if (!get_u8(&ret, buf, 10))
  58                 return ret;
  59
  60         pe = getprotobyname(buf);
  61         if (pe) {
  62                 if (icache != -1)
  63                         free(ncache);
  64                 icache = pe->p_proto;
  65                 ncache = strdup(pe->p_name);
  66                 return pe->p_proto;
  67         }
  68         return -1;
  69 }