lib/getaddrinfo.c

   1 /*
   2  * getaddrinfo.c
   3  *
   4  * Simple version of getaddrinfo()
   5  *
   6  */
   7
   8 #include "config.h"
   9
  10 extern int errno;
  11 extern int h_errno;
  12
  13 void freeaddrinfo(struct addrinfo *res)
  14 {
  15     if (!res)
  16         return;
  17     if (res->ai_next)
  18         freeaddrinfo(res->ai_next);
  19     if (res->ai_addr)
  20         free(res->ai_addr);
  21     if (res->ai_canonname)
  22         free(res->ai_canonname);
  23     free(res);
  24 }
  25
  26 int getaddrinfo(const char *node, const char *service, const struct addrinfo *hints,
  27                 struct addrinfo **res)
  28 {
  29     struct hostent  *host;
  30     struct sockaddr *sa;
  31     int err, size = 0;
  32
  33     if ((!node) || (!res)) {
  34         errno = EINVAL;
  35         return EAI_SYSTEM;
  36     }
  37     *res = NULL;
  38     /* we do not support service in this version */
  39     if (service) {
  40         errno = EINVAL;
  41         return EAI_SYSTEM;
  42     }
  43     host = gethostbyname(node);
  44     if (!host)
  45         return EAI_NONAME;
  46     if (hints) {
  47         if (hints->ai_family != AF_UNSPEC) {
  48             if (hints->ai_family != host->h_addrtype)
  49                 return EAI_ADDRFAMILY;
  50         }
  51     }
  52     *res =  malloc(sizeof(struct addrinfo));
  53     if (!*res) {
  54         return EAI_MEMORY;
  55     }
  56     memset(*res, 0, sizeof(struct addrinfo));
  57     (*res)->ai_family = host->h_addrtype;
  58     if (host->h_length) {
  59         if (host->h_addrtype == AF_INET)
  60             size = sizeof(struct sockaddr_in);
  61 #ifdef HAVE_IPV6
  62         else if (host->h_addrtype == AF_INET6)
  63             size = sizeof(struct sockaddr_in6);
  64 #endif
  65         else {
  66             free(*res);
  67             *res = NULL;
  68             return EAI_ADDRFAMILY;
  69         }
  70         sa = malloc(size);
  71         if (!sa) {
  72             free(*res);
  73             *res = NULL;
  74             return EAI_MEMORY;
  75         }
  76         memset(sa, 0, size);
  77         (*res)->ai_addr = sa;
  78         (*res)->ai_addrlen = size;
  79         sa->sa_family = host->h_addrtype;
  80         if (host->h_addrtype == AF_INET)
  81             memcpy(&((struct sockaddr_in *)sa)->sin_addr, host->h_addr, host->h_length);
  82 #ifdef HAVE_IPV6
  83         else
  84             memcpy(&((struct sockaddr_in6 *)sa)->sin6_addr, host->h_addr, host->h_length);
  85 #endif
  86     }
  87     if (host->h_name)
  88        (*res)->ai_canonname = strdup(host->h_name);
  89
  90     /* we only handle the first address entry and do not build a list now */
  91     return 0;
  92 }
  93
  94
  95
  96 const char *gai_strerror(int errcode)
  97 {
  98     const char *s = NULL;
  99
 100     switch(errcode) {
 101     case 0:
 102         s = "no error";
 103         break;
 104     case EAI_MEMORY:
 105         s = "no memory";
 106         break;
 107     case EAI_SYSTEM:
 108         s = strerror(errno);
 109         break;
 110     case EAI_NONAME:
 111         s = hstrerror(h_errno);
 112         break;
 113     case EAI_ADDRFAMILY:
 114         s = "address does not match address family";
 115         break;
 116     default:
 117         s = "unknown error code";
 118         break;
 119     }
 120     return s;
 121 }