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 <syslog.h>
  17 #include <fcntl.h>
  18 #include <sys/socket.h>
  19 #include <netinet/in.h>
  20 #include <netdb.h>
  21 #include <string.h>
  22
  23 #include "rt_names.h"
  24 #include "utils.h"
  25
  26 const char *inet_proto_n2a(int proto, char *buf, int len)
  27 {
  28         static char *ncache;
  29         static int icache = -1;
  30         struct protoent *pe;
  31
  32         if (proto == icache)
  33                 return ncache;
  34
  35         pe = getprotobynumber(proto);
  36         if (pe) {
  37                 if (icache != -1)
  38                         free(ncache);
  39                 icache = proto;
  40                 ncache = strdup(pe->p_name);
  41                 strlcpy(buf, pe->p_name, len);
  42                 return buf;
  43         }
  44         snprintf(buf, len, "ipproto-%d", proto);
  45         return buf;
  46 }
  47
  48 int inet_proto_a2n(const char *buf)
  49 {
  50         static char *ncache;
  51         static int icache = -1;
  52         struct protoent *pe;
  53         __u8 ret;
  54
  55         if (icache != -1 && strcmp(ncache, buf) == 0)
  56                 return icache;
  57
  58         if (!get_u8(&ret, buf, 10))
  59                 return ret;
  60
  61         pe = getprotobyname(buf);
  62         if (pe) {
  63                 if (icache != -1)
  64                         free(ncache);
  65                 icache = pe->p_proto;
  66                 ncache = strdup(pe->p_name);
  67                 return pe->p_proto;
  68         }
  69         return -1;
  70 }