BSD 4_4_Lite1 release

[unix-history] / usr / src / contrib / mh-6.8.3a / mts / sendmail / hosts.c

/* hosts.c - find out the official name of a host */
#ifndef lint
static char ident[] = "@(#)$Id: hosts.c,v 1.7 1992/12/15 00:20:22 jromine Exp $";
#endif  /* lint */

/* LINTLIBRARY */

/* In the SendMail world, we really don't know what the valid hosts are.
  We could poke around in the sendmail.cf file, but that still isn't a
  guarantee.  As a result, we'll say that everything is a valid host, and
  let SendMail worry about it. */


#include "../h/strings.h"
#include <stdio.h>
#include "../zotnet/mts.h"
#include <ctype.h>
#if     defined(BSD42) || defined(SOCKETS)
#include <netdb.h>
#endif  /* BSD42 or SOCKETS */


#define NOTOK   (-1)


static struct host {
   char   *h_name;
   char  **h_aliases;
   struct host   *h_next;
}                   hosts;

char   *getcpy ();

static int      init_hs();

/* \f */

char   *OfficialName (name)
register char   *name;
{
   register char  *p;
   char   *q,
           site[BUFSIZ];
#if     defined(BSD42) || defined(SOCKETS)
   register struct hostent *hp;
#endif  /* BSD42 or SOCKETS */
   static char buffer[BUFSIZ];
   register char **r;
   register struct host   *h;

   for (p = name, q = site; *p; p++, q++)
       *q = isupper (*p) ? tolower (*p) : *p;
   *q = 0;
   q = site;

   if (uleq (LocalName (), site))
       return LocalName ();

#ifdef  BSD41A
   if (rhost (&q) != NOTOK) {
       (void) strcpy (buffer, q);
       free (q);
       return buffer;
   }
#endif  /* BSD41A */
#if     defined(BSD42) || defined(SOCKETS)
#ifndef BIND
   sethostent (1);
#endif
   if (hp = gethostbyname (q)) {
       (void) strcpy (buffer, hp -> h_name);
       return buffer;
   }
#endif  /* BSD42 or SOCKETS */

   if (hosts.h_name || init_hs ())
       for (h = hosts.h_next; h; h = h -> h_next)
           if (uleq (h -> h_name, q))
               return h -> h_name;
           else
               for (r = h -> h_aliases; *r; r++)
                   if (uleq (*r, q))
                       return h -> h_name;

   (void) strcpy (buffer, site);
   return buffer;
}

/* \f */

/* Use hostable as an exception file for those hosts that aren't on the
  Internet (listed in /etc/hosts).  These are usually PhoneNet and UUCP
  sites. */


#define NALIASES        50

static int  init_hs () {
   register char  *cp,
                  *dp,
                 **q,
                 **r;
   char    buffer[BUFSIZ],
          *aliases[NALIASES];
   register struct host   *h;
   register FILE  *fp;

   if ((fp = fopen (hostable, "r")) == NULL)
       return 0;

   h = &hosts;
   while (fgets (buffer, sizeof buffer, fp) != NULL) {
       if (cp = index (buffer, '#'))
           *cp = 0;
       if (cp = index (buffer, '\n'))
           *cp = 0;
       for (cp = buffer; *cp; cp++)
           if (isspace (*cp))
               *cp = ' ';
       for (cp = buffer; isspace (*cp); cp++)
           continue;
       if (*cp == 0)
           continue;

       q = aliases;
       if (cp = index (dp = cp, ' ')) {
           *cp = 0;
           for (cp++; *cp; cp++) {
               while (isspace (*cp))
                   cp++;
               if (*cp == 0)
                   break;
               if (cp = index (*q++ = cp, ' '))
                   *cp = 0;
               else
                   break;
               if (q >= aliases + NALIASES)
                   break;
           }
       }

       *q = 0;

       h -> h_next = (struct host *) calloc (1, sizeof *h);
       h = h -> h_next;
       h -> h_name = getcpy (dp);
       r = h -> h_aliases =
               (char **) calloc ((unsigned) (q - aliases + 1), sizeof *q);
       for (q = aliases; *q; q++)
           *r++ = getcpy (*q);
       *r = 0;
   }

   (void) fclose (fp);
   return 1;
}