usr/src/cmd/nscd/nscd_biggest.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #pragma ident   "%Z%%M% %I%     %E% SMI"
  27
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <stdlib.h>
  31
  32 #include "cache.h"
  33
  34 nsc_keephot_t *
  35 maken(int n)
  36 {
  37         nsc_keephot_t   *ret;
  38
  39         ++n;
  40         ret = (nsc_keephot_t *)calloc(n, sizeof (nsc_keephot_t));
  41         if (ret == NULL)
  42                 return (NULL);
  43         ret[0].num = n - 1;
  44         return (ret);
  45 }
  46
  47 void *
  48 insertn(nsc_keephot_t *table, uint_t n, void *data)
  49 {
  50         void    *olddata;
  51         int     size, guess, base, last;
  52
  53         if (n < 1 || table[1].num > n) {
  54                 return (data);
  55         }
  56
  57         size = table[0].num;
  58         if (table[size].num < n)  /* biggest so far */
  59                 guess = size;
  60         else {
  61                 base = 1;
  62                 last = size;
  63                 while (last >= base) {
  64                         guess = (last+base)/2;
  65                         if (table[guess].num == n)
  66                                 goto doit;
  67                         if (table[guess].num > n)
  68                                 last = guess - 1;
  69                         else
  70                                 base = guess + 1;
  71                 }
  72                 guess = last;
  73         }
  74
  75 doit:
  76         olddata = table[1].ptr;
  77         (void) memmove(table + 1, table + 2,
  78                         sizeof (nsc_keephot_t) * (guess-1));
  79         table[guess].ptr = data;
  80         table[guess].num = n;
  81         return (olddata);
  82 }