m4/hash.h

   1 /* GNU m4 -- A simple macro processor
   2    Copyright (C) 2001, 2006-2007, 2010, 2013-2014, 2017 Free Software
   3    Foundation, Inc.
   4    Written by Gary V. Vaughan <gary@gnu.org>
   5
   6    This file is part of GNU M4.
   7
   8    GNU M4 is free software: you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation, either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    GNU M4 is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #ifndef M4_HASH_H
  23 #define M4_HASH_H 1
  24
  25 #include <m4/system.h>
  26
  27 /* Must be 1 less than a power of 2 for the resize algorithm to
  28    be efficient.  */
  29 #define M4_HASH_DEFAULT_SIZE    511
  30
  31 /* When the average number of values per bucket breaks this value
  32    the table will be grown to reduce the density accordingly.  */
  33 #define M4_HASH_MAXIMUM_DENSITY 3.0
  34
  35 BEGIN_C_DECLS
  36
  37 typedef struct m4_hash m4_hash;
  38
  39 typedef size_t  m4_hash_hash_func (const void *key);
  40 typedef int     m4_hash_cmp_func  (const void *key, const void *try);
  41 typedef void *  m4_hash_copy_func (m4_hash *src, const void *key, void *value,
  42                                    m4_hash *dest);
  43
  44 extern m4_hash *m4_hash_new     (size_t size, m4_hash_hash_func *hash_func,
  45                                  m4_hash_cmp_func *cmp_func);
  46 extern m4_hash *m4_hash_dup     (m4_hash *hash, m4_hash_copy_func *copy);
  47 extern void     m4_hash_delete  (m4_hash *hash);
  48 extern void     m4_hash_exit    (void);
  49
  50 extern size_t   m4_get_hash_length      (m4_hash *hash);
  51
  52 extern void **          m4_hash_lookup  (m4_hash *hash, const void *key);
  53 extern void *           m4_hash_remove  (m4_hash *hash, const void *key);
  54 extern const void *     m4_hash_insert  (m4_hash *hash, const void *key,
  55                                          void *value);
  56
  57
  58 \f
  59 extern size_t   m4_hash_string_hash (const void *key);
  60 extern int      m4_hash_string_cmp  (const void *key, const void *try);
  61
  62
  63 \f
  64 typedef struct m4_hash_iterator m4_hash_iterator;
  65 typedef void *  m4_hash_apply_func  (m4_hash *hash, const void *key,
  66                                      void *value, void *userdata);
  67
  68 extern void *   m4_hash_apply       (m4_hash *hash, m4_hash_apply_func *func,
  69                                      void *userdata);
  70
  71 extern const void *      m4_get_hash_iterator_key   (m4_hash_iterator *place);
  72 extern void *            m4_get_hash_iterator_value (m4_hash_iterator *place);
  73 extern m4_hash_iterator *m4_get_hash_iterator_next  (const m4_hash *hash,
  74                                                      m4_hash_iterator *place);
  75 extern void              m4_free_hash_iterator      (const m4_hash *hash,
  76                                                      m4_hash_iterator *place);
  77
  78
  79 END_C_DECLS
  80
  81 #endif /* !M4_HASH_H */