lib/hash.h

   1 /* Hash routine.
   2    Copyright (C) 1998 Kunihiro Ishiguro
   3
   4 This file is part of GNU Zebra.
   5
   6 GNU Zebra is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published
   8 by the Free Software Foundation; either version 2, or (at your
   9 option) any later version.
  10
  11 GNU Zebra is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Zebra; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef _ZEBRA_HASH_H
  22 #define _ZEBRA_HASH_H
  23
  24 /* Default hash table size.  */
  25 #define HASHTABSIZE     1024
  26
  27 struct hash_backet
  28 {
  29   /* Linked list.  */
  30   struct hash_backet *next;
  31
  32   /* Hash key. */
  33   unsigned int key;
  34
  35   /* Data.  */
  36   void *data;
  37 };
  38
  39 struct hash
  40 {
  41   /* Hash backet. */
  42   struct hash_backet **index;
  43
  44   /* Hash table size. */
  45   unsigned int size;
  46
  47   /* Key make function. */
  48   unsigned int (*hash_key) (void *);
  49
  50   /* Data compare function. */
  51   int (*hash_cmp) (const void *, const void *);
  52
  53   /* Backet alloc. */
  54   unsigned long count;
  55 };
  56
  57 extern struct hash *hash_create (unsigned int (*) (void *),
  58                                  int (*) (const void *, const void *));
  59 extern struct hash *hash_create_size (unsigned int, unsigned int (*) (void *),
  60                                              int (*) (const void *, const void *));
  61
  62 extern void *hash_get (struct hash *, void *, void * (*) (void *));
  63 extern void *hash_alloc_intern (void *);
  64 extern void *hash_lookup (struct hash *, void *);
  65 extern void *hash_release (struct hash *, void *);
  66
  67 extern void hash_iterate (struct hash *,
  68                    void (*) (struct hash_backet *, void *), void *);
  69
  70 extern void hash_clean (struct hash *, void (*) (void *));
  71 extern void hash_free (struct hash *);
  72
  73 extern unsigned int string_hash_make (const char *);
  74
  75 #endif /* _ZEBRA_HASH_H */