nis/nis_lookup.c

   1 /* Copyright (C) 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@uni-paderborn.de>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <string.h>
  21 #include <rpcsvc/nis.h>
  22
  23 #include "nis_intern.h"
  24
  25 nis_result *
  26 nis_lookup (const_nis_name name, const u_long flags)
  27 {
  28   nis_result *res;
  29   struct ns_request req;
  30   nis_name *names;
  31   nis_error status;
  32   int count_links = 0;   /* We will follow only 16 links in the deep */
  33   int done = 0;
  34   int name_nr = 0;
  35   nis_name namebuf[2] = {NULL, NULL};
  36
  37   res = calloc (1, sizeof (nis_result));
  38
  39   if (flags & EXPAND_NAME)
  40     {
  41       names = nis_getnames (name);
  42       if (names == NULL)
  43         {
  44           res->status = NIS_NAMEUNREACHABLE;
  45           return res;
  46         }
  47     }
  48   else
  49     {
  50       names = namebuf;
  51       names[0] = (nis_name) name;
  52     }
  53
  54   req.ns_name = names[0];
  55   while (!done)
  56     {
  57       req.ns_object.ns_object_len = 0;
  58       req.ns_object.ns_object_val = NULL;
  59       memset (res, '\0', sizeof (nis_result));
  60
  61       status = __do_niscall (req.ns_name, NIS_LOOKUP,
  62                              (xdrproc_t) xdr_ns_request,
  63                              (caddr_t) & req,
  64                              (xdrproc_t) xdr_nis_result,
  65                              (caddr_t) res, flags, NULL);
  66       if (status != NIS_SUCCESS)
  67         res->status = status;
  68
  69       switch (res->status)
  70         {
  71         case NIS_PARTIAL:
  72         case NIS_SUCCESS:
  73         case NIS_S_SUCCESS:
  74           if (__type_of(NIS_RES_OBJECT (res)) == NIS_LINK_OBJ &&
  75               flags & FOLLOW_LINKS) /* We are following links */
  76             {
  77               /* if we hit the link limit, bail */
  78               if (count_links > NIS_MAXLINKS)
  79                 {
  80                   res->status = NIS_LINKNAMEERROR;
  81                   ++done;
  82                   break;
  83                 }
  84               if (count_links)
  85                 free (req.ns_name);
  86               ++count_links;
  87               req.ns_name = strdup (NIS_RES_OBJECT (res)->LI_data.li_name);
  88               nis_freeresult (res);
  89               res = calloc (1, sizeof (nis_result));
  90             }
  91           else
  92             ++done;
  93           break;
  94         case NIS_CBRESULTS:
  95           /* The callback is handled in __do_niscall2 */
  96           ++done;
  97           break;
  98         case NIS_UNAVAIL:
  99           /* NIS+ is not installed, or all servers are down */
 100           ++done;
 101           break;
 102         default:
 103           /* Try the next domainname if we don't follow a link */
 104           if (count_links)
 105             {
 106               free (req.ns_name);
 107               res->status = NIS_LINKNAMEERROR;
 108               ++done;
 109               break;
 110             }
 111           ++name_nr;
 112           if (names[name_nr] == NULL)
 113             {
 114               ++done;
 115               break;
 116             }
 117           req.ns_name = names[name_nr];
 118           break;
 119         }
 120     }
 121
 122   if (names != namebuf)
 123     nis_freenames (names);
 124
 125   return res;
 126 }