nis/nis_util.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@vt.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 #include "nis_intern.h"
  23
  24 fd_result *
  25 __nis_finddirectory (directory_obj *dir, const_nis_name name)
  26 {
  27   fd_args fd_args;
  28   fd_result *fd_res;
  29
  30   fd_args.dir_name = strdup (name);
  31   fd_args.requester = nis_local_host();
  32   fd_res = calloc (1, sizeof (fd_result));
  33
  34   if (__do_niscall2 (dir->do_servers.do_servers_val,
  35                      dir->do_servers.do_servers_len, NIS_FINDDIRECTORY,
  36                      (xdrproc_t) xdr_fd_args,
  37                      (caddr_t) &fd_args, (xdrproc_t) xdr_fd_result,
  38                      (caddr_t) fd_res, NO_AUTHINFO|USE_DGRAM) != NIS_SUCCESS)
  39     fd_res->status = NIS_RPCERROR;
  40
  41   return fd_res;
  42 }
  43
  44 /* This is from libc/db/hash/hash_func.c, hash3 is static there */
  45 /*
  46  * This is INCREDIBLY ugly, but fast.  We break the string up into 8 byte
  47  * units.  On the first time through the loop we get the "leftover bytes"
  48  * (strlen % 8).  On every other iteration, we perform 8 HASHC's so we handle
  49  * all 8 bytes.  Essentially, this saves us 7 cmp & branch instructions.  If
  50  * this routine is heavily used enough, it's worth the ugly coding.
  51  *
  52  * OZ's original sdbm hash
  53  */
  54 unsigned long
  55 __nis_hash (const void *keyarg, register size_t len)
  56 {
  57   register const u_char *key;
  58   register size_t loop;
  59   register u_int32_t h;
  60
  61 #define HASHC   h = *key++ + 65599 * h
  62
  63   h = 0;
  64   key = keyarg;
  65   if (len > 0)
  66     {
  67       loop = (len + 8 - 1) >> 3;
  68       switch (len & (8 - 1))
  69         {
  70         case 0:
  71           do {
  72             HASHC;
  73             /* FALLTHROUGH */
  74           case 7:
  75             HASHC;
  76             /* FALLTHROUGH */
  77           case 6:
  78             HASHC;
  79             /* FALLTHROUGH */
  80           case 5:
  81             HASHC;
  82             /* FALLTHROUGH */
  83           case 4:
  84             HASHC;
  85             /* FALLTHROUGH */
  86           case 3:
  87             HASHC;
  88             /* FALLTHROUGH */
  89           case 2:
  90             HASHC;
  91             /* FALLTHROUGH */
  92           case 1:
  93             HASHC;
  94           } while (--loop);
  95         }
  96     }
  97   return (h);
  98 }
  99