usr/src/cmd/ypcmd/revnetgroup/table.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, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1994, by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #ident  "%Z%%M% %I%     %E% SMI"        /* SMI4.1 1.4 */
  28
  29 #include <ctype.h>
  30 #include "util.h"
  31 #include "table.h"
  32
  33
  34
  35 /*
  36  * Hash table manager. Store/lookup strings, keyed by string
  37  */
  38
  39 /*
  40  * Generate the key into the table using the first two letters
  41  * of "str".  The table is alphabetized, with no distinction between
  42  * upper and lower case.  Non-letters are given least significance.
  43  */
  44 int
  45 tablekey(str)
  46         register char *str;
  47 {
  48 #define TOLOWER(c) (islower(c) ? c : \
  49                         (isupper(c) ? tolower(c) : ('a'+NUMLETTERS-1)))
  50
  51         register int c1, c2;
  52
  53         c1 = *str++;
  54         c2 = *str;
  55         if (c1 == EOS) {
  56                 c2 = EOS;       /* just in case */
  57         }
  58         c1 = TOLOWER(c1) - 'a';
  59         c2 = TOLOWER(c2) - 'a';
  60         return (c1*NUMLETTERS + c2);
  61 }
  62
  63
  64 void
  65 store(table, key, datum)
  66         stringtable table;
  67         char *key;
  68         char *datum;
  69 {
  70         int index;
  71         tablelist cur, new;
  72
  73         index = tablekey(key);
  74         cur = table[index];
  75
  76         new = MALLOC(tablenode);
  77         new->key = key;
  78         new->datum = datum;
  79         new->next = cur;
  80         table[index] = new;
  81 }
  82
  83
  84 char *
  85 lookup(table, key)
  86         stringtable table;
  87         char *key;
  88 {
  89         tablelist cur;
  90
  91         cur = table[tablekey(key)];
  92         while (cur && strcmp(cur->key, key)) {
  93                 cur = cur->next;
  94         }
  95         if (cur) {
  96                 return (cur->datum);
  97         } else {
  98                 return (NULL);
  99         }
 100 }