src/inet_ntop_cache.c

   1 #include "first.h"
   2
   3 #include "inet_ntop_cache.h"
   4
   5 #include "sys-socket.h"
   6 #include <sys/types.h>
   7 #include <string.h>
   8 #ifndef _WIN32
   9 #include <arpa/inet.h>
  10 #endif
  11
  12 #include "sock_addr.h"
  13
  14
  15 const char * inet_ntop_cache_get_ip(server *srv, sock_addr *addr) {
  16 #ifdef HAVE_IPV6
  17         typedef struct {
  18                 int family;
  19                 union {
  20                         struct in6_addr ipv6;
  21                         struct in_addr  ipv4;
  22                 } addr;
  23                 char b2[INET6_ADDRSTRLEN + 1];
  24         } inet_ntop_cache_type;
  25         #define INET_NTOP_CACHE_MAX 4
  26         static inet_ntop_cache_type inet_ntop_cache[INET_NTOP_CACHE_MAX];
  27         static int ndx;
  28
  29         int i;
  30         UNUSED(srv);
  31       #ifdef HAVE_SYS_UN_H
  32         if (addr->plain.sa_family == AF_UNIX) return addr->un.sun_path;
  33       #endif
  34         for (i = 0; i < INET_NTOP_CACHE_MAX; i++) {
  35                 if (inet_ntop_cache[i].family == addr->plain.sa_family) {
  36                         if (inet_ntop_cache[i].family == AF_INET6 &&
  37                             0 == memcmp(inet_ntop_cache[i].addr.ipv6.s6_addr, addr->ipv6.sin6_addr.s6_addr, 16)) {
  38                                 /* IPv6 found in cache */
  39                                 break;
  40                         } else if (inet_ntop_cache[i].family == AF_INET &&
  41                                    inet_ntop_cache[i].addr.ipv4.s_addr == addr->ipv4.sin_addr.s_addr) {
  42                                 /* IPv4 found in cache */
  43                                 break;
  44
  45                         }
  46                 }
  47         }
  48
  49         if (i == INET_NTOP_CACHE_MAX) {
  50                 /* not found in cache */
  51                 const char *s;
  52
  53                 i = ndx;
  54                 if (++ndx >= INET_NTOP_CACHE_MAX) ndx = 0;
  55                 s = sock_addr_inet_ntop(addr, inet_ntop_cache[i].b2, INET6_ADDRSTRLEN);
  56                 if (NULL == s) return "";
  57
  58                 inet_ntop_cache[i].family = addr->plain.sa_family;
  59
  60                 if (inet_ntop_cache[i].family == AF_INET) {
  61                         inet_ntop_cache[i].addr.ipv4.s_addr = addr->ipv4.sin_addr.s_addr;
  62                 } else if (inet_ntop_cache[i].family == AF_INET6) {
  63                         memcpy(inet_ntop_cache[i].addr.ipv6.s6_addr, addr->ipv6.sin6_addr.s6_addr, 16);
  64                 }
  65         }
  66
  67         return inet_ntop_cache[i].b2;
  68 #else
  69         UNUSED(srv);
  70         if (addr->plain.sa_family == AF_INET) return inet_ntoa(addr->ipv4.sin_addr);
  71       #ifdef HAVE_SYS_UN_H
  72         if (addr->plain.sa_family == AF_UNIX) return addr->un.sun_path;
  73       #endif
  74         return "";
  75 #endif
  76 }