+
+/**
+ Convert a string to an IP address. The string can be a name or
+ dotted decimal number.
+
+ Returns a pointer to a static in_addr struct -- if you call this
+ more than once then you should copy it.
+*/
+struct in_addr *ip_address(const char *str)
+{
+ static struct in_addr ret;
+ struct hostent *hp;
+
+ if (!str) {
+ rprintf (FERROR, "ip_address received NULL name\n");
+ return NULL;
+ }
+
+ /* try as an IP address */
+ if (inet_aton(str, &ret) != 0) {
+ return &ret;
+ }
+
+ /* otherwise assume it's a network name of some sort and use
+ gethostbyname */
+ if ((hp = gethostbyname (str)) == 0) {
+ rprintf(FERROR, "gethostbyname failed for \"%s\": unknown host?\n",str);
+ return NULL;
+ }
+
+ if (hp->h_addr == NULL) {
+ rprintf(FERROR, "gethostbyname: host address is invalid for host \"%s\"\n",str);
+ return NULL;
+ }
+
+ if (hp->h_length > sizeof ret) {
+ rprintf(FERROR, "gethostbyname: host address for \"%s\" is too large\n",
+ str);
+ return NULL;
+ }
+
+ if (hp->h_addrtype != AF_INET) {
+ rprintf (FERROR, "gethostname: host address for \"%s\" is not IPv4\n",
+ str);
+ return NULL;
+ }
+
+ /* This is kind of difficult. The only field in ret is
+ s_addr, which is the IP address as a 32-bit int. On
+ UNICOS, s_addr is in fact a *bitfield* for reasons best
+ know to Cray. This means we can't memcpy in to it. On the
+ other hand, h_addr is a char*, so we can't just assign.
+
+ Since there's meant to be only one field inside the in_addr
+ structure we will try just copying over the top and see how
+ that goes. */
+ memcpy (&ret, hp->h_addr, hp->h_length);
+
+ return &ret;
+}