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/* $Id: getfqdn.c 6155 2003-01-19 19:58:25Z rra $
**
*/
#include "config.h"
#include "clibrary.h"
#include <netdb.h>
#include "libinn.h"
#include "paths.h"
/*
** Get the fully-qualified domain name for this host.
*/
char *GetFQDN(char *domain)
{
static char buff[SMBUF];
struct hostent *hp;
char *p;
char **ap;
#if 0
/* See comments below. */
char temp[SMBUF + 2];
#endif /* 0 */
/* Return any old results. */
if (buff[0])
return buff;
/* Try gethostname. */
if (gethostname(buff, (int)sizeof buff) < 0)
return NULL;
if (strchr(buff, '.') != NULL)
return buff;
/* See if DNS (or /etc/hosts) gives us a full domain name. */
if ((hp = gethostbyname(buff)) == NULL)
return NULL;
#if 0
/* This code is a "feature" that allows multiple domains (NIS or
* DNS, I'm not sure) to work with a single INN server. However,
* it turns out to cause more problems for people, and they have to
* use hacks like __switch_gethostbyname, etc. So if you need this,
* turn it on, but don't complain to me. */
if (strchr(hp->h_name, '.') == NULL) {
/* Try to force DNS lookup if NIS/whatever gets in the way. */
strlcpy(temp, buff, sizeof(temp));
strlcat(temp, ".", sizeof(temp));
hp = gethostbyname(temp);
}
#endif /* 0 */
/* First, see if the main name is a FQDN. It should be. */
if (hp != NULL && strchr(hp->h_name, '.') != NULL) {
if (strlen(hp->h_name) < sizeof buff - 1) {
strlcpy(buff, hp->h_name, sizeof(buff));
return buff;
}
/* Doesn't fit; make sure we don't return bad data next time. */
buff[0] = '\0';
return hp->h_name;
}
/* Second, see if any aliases are. */
if ((ap = hp->h_aliases) != NULL)
while ((p = *ap++) != NULL)
if (strchr(p, '.') != NULL) {
/* Deja-vous all over again. */
if (strlen(p) < sizeof buff - 1) {
strlcpy(buff, p, sizeof(buff));
return buff;
}
buff[0] = '\0';
return p ;
}
/* Give up: Get the domain config param and append it. */
if ((p = domain) == NULL || *p == '\0')
return NULL;
if (strlen(buff) + 1 + strlen(p) > sizeof buff - 1)
/* Doesn't fit. */
return NULL;
strlcat(buff, ".", sizeof(buff));
strlcat(buff, p, sizeof(buff));
return buff;
}
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