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Include @<ctype.h>@.
[mLib] / assoc.h
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dcda5944 1/* -*-c-*-
2 *
67a35c5d 3 * $Id: assoc.h,v 1.2 2001/01/25 21:12:22 mdw Exp $
dcda5944 4 *
5 * Assocation tables
6 *
7 * (c) 2000 Straylight/Edgeware
8 */
9
10/*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
18 *
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30/*----- Revision history --------------------------------------------------*
31 *
32 * $Log: assoc.h,v $
67a35c5d 33 * Revision 1.2 2001/01/25 21:12:22 mdw
34 * Add new macro to find an association's atom key.
35 *
dcda5944 36 * Revision 1.1 2001/01/20 11:50:58 mdw
37 * Hash tables indexed by atoms, to avoid expense of hashing keys on each
38 * lookup, and to reduce storage used by key texts.
39 *
40 */
41
42#ifndef MLIB_ASSOC_H
43#define MLIB_ASSOC_H
44
45#ifdef __cplusplus
46 extern "C" {
47#endif
48
49/*----- Header files ------------------------------------------------------*/
50
51#ifndef MLIB_ATOM_H
52# include "atom.h"
53#endif
54
55#ifndef MLIB_HASH_H
56# include "hash.h"
57#endif
58
59/*----- Data structures ---------------------------------------------------*/
60
61typedef struct assoc_table {
62 hash_table t;
63 size_t load;
64} assoc_table;
65
66typedef struct assoc_base {
67 hash_base b;
68 atom *a;
69} assoc_base;
70
71typedef struct { hash_iter i; } assoc_iter;
72
67a35c5d 73#define ASSOC_ATOM(p) (((assoc_base *)(p))->a + 0)
74
dcda5944 75/*----- Functions provided ------------------------------------------------*/
76
77/* --- @assoc_create@ --- *
78 *
79 * Arguments: @assoc_table *t@ = pointer to an association table
80 *
81 * Returns: ---
82 *
83 * Use: Creates a new association table.
84 */
85
86extern void assoc_create(assoc_table */*t*/);
87
88/* --- @assoc_destroy@ --- *
89 *
90 * Arguments: @assoc_table *t@ = pointer to an association table
91 *
92 * Returns: ---
93 *
94 * Use: Destroys an association table.
95 */
96
97extern void assoc_destroy(assoc_table */*t*/);
98
99/* --- @assoc_find@ --- *
100 *
101 * Arguments: @assoc_table *t@ = pointer to an association table
102 * @atom *a@ = an atom to label the item
103 * @size_t sz@ = size of block to allocate
104 * @unsigned *f@ = pointer to `found' flag
105 *
106 * Returns: A pointer to the item located or null.
107 *
108 * Use: Looks up an atom in an association table. If the atom is
109 * found, the association is returned. If not, and @sz@ is
110 * zero, a null pointer is returned. Otherwise, a block of size
111 * @sz@ is allocated, its @assoc_base@ header is filled in, and
112 * the pointer returned. The flag @*f@ is cleared if the item
113 * couldn't be found, or set if it was.
114 *
115 * All the atoms used in a particular table should
116 */
117
118extern void *assoc_find(assoc_table */*t*/, atom */*a*/,
119 size_t /*sz*/, unsigned */*f*/);
120
121/* --- @assoc_remove@ --- *
122 *
123 * Arguments: @assoc_table *t@ = pointer to an association table
124 * @void *p@ = pointer to a block to remove
125 *
126 * Returns: ---
127 *
128 * Use: Removes an association from a table.
129 */
130
131extern void assoc_remove(assoc_table */*t*/, void */*p*/);
132
133/* --- @assoc_mkiter@, @assoc_next@ --- *
134 *
135 * Arguments: @assoc_iter *i@ = pointer to an iterator
136 * @assoc_table *t@ = pointer to an association table
137 *
138 * Returns: Next association, or null, for @assoc_next@; nothing for
139 * @assoc_mkiter@.
140 *
141 * Use: Iterates over the associations in a table.
142 */
143
144#define ASSOC_MKITER(i_, t_) HASH_MKITER(&(i_)->i, &(t_)->t)
145
146#define ASSOC_NEXT(i_, p) do { \
147 hash_base *_q; \
148 HASH_NEXT(&(i_)->i, _q); \
149 (p) = (void *)_q; \
150} while (0)
151
152extern void assoc_mkiter(assoc_iter */*i*/, assoc_table */*t*/);
153extern void *assoc_next(assoc_iter */*i*/);
154
155/*----- That's all, folks -------------------------------------------------*/
156
157#ifdef __cplusplus
158 }
159#endif
160
161#endif