1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
|
/*
* Copyright (C) 1989-95 GROUPE BULL
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* GROUPE BULL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* Except as contained in this notice, the name of GROUPE BULL shall not be
* used in advertising or otherwise to promote the sale, use or other dealings
* in this Software without prior written authorization from GROUPE BULL.
*/
/*****************************************************************************\
* hashtab.c: *
* *
* XPM library *
* *
* Developed by Arnaud Le Hors *
* this originaly comes from Colas Nahaboo as a part of Wool *
* *
\*****************************************************************************/
#include "XpmI.h"
LFUNC(AtomMake, xpmHashAtom, (char *name, void *data));
LFUNC(HashTableGrows, int, (xpmHashTable * table));
static xpmHashAtom
AtomMake(name, data) /* makes an atom */
char *name; /* WARNING: is just pointed to */
void *data;
{
xpmHashAtom object = (xpmHashAtom) XpmMalloc(sizeof(struct _xpmHashAtom));
if (object) {
object->name = name;
object->data = data;
}
return object;
}
/************************\
* *
* hash table routines *
* *
\************************/
/*
* Hash function definition:
* HASH_FUNCTION: hash function, hash = hashcode, hp = pointer on char,
* hash2 = temporary for hashcode.
* INITIAL_TABLE_SIZE in slots
* HASH_TABLE_GROWS how hash table grows.
*/
/* Mock lisp function */
#define HASH_FUNCTION hash = (hash << 5) - hash + *hp++;
/* #define INITIAL_HASH_SIZE 2017 */
#define INITIAL_HASH_SIZE 256 /* should be enough for colors */
#define HASH_TABLE_GROWS size = size * 2;
/* aho-sethi-ullman's HPJ (sizes should be primes)*/
#ifdef notdef
#define HASH_FUNCTION hash <<= 4; hash += *hp++; \
if(hash2 = hash & 0xf0000000) hash ^= (hash2 >> 24) ^ hash2;
#define INITIAL_HASH_SIZE 4095 /* should be 2^n - 1 */
#define HASH_TABLE_GROWS size = size << 1 + 1;
#endif
/* GNU emacs function */
/*
#define HASH_FUNCTION hash = (hash << 3) + (hash >> 28) + *hp++;
#define INITIAL_HASH_SIZE 2017
#define HASH_TABLE_GROWS size = size * 2;
*/
/* end of hash functions */
/*
* The hash table is used to store atoms via their NAME:
*
* NAME --hash--> ATOM |--name--> "foo"
* |--data--> any value which has to be stored
*
*/
/*
* xpmHashSlot gives the slot (pointer to xpmHashAtom) of a name
* (slot points to NULL if it is not defined)
*
*/
xpmHashAtom *
xpmHashSlot(table, s)
xpmHashTable *table;
char *s;
{
xpmHashAtom *atomTable = table->atomTable;
unsigned int hash;
xpmHashAtom *p;
char *hp = s;
char *ns;
hash = 0;
while (*hp) { /* computes hash function */
HASH_FUNCTION
}
p = atomTable + hash % table->size;
while (*p) {
ns = (*p)->name;
if (ns[0] == s[0] && strcmp(ns, s) == 0)
break;
p--;
if (p < atomTable)
p = atomTable + table->size - 1;
}
return p;
}
static int
HashTableGrows(table)
xpmHashTable *table;
{
xpmHashAtom *atomTable = table->atomTable;
unsigned int size = table->size;
xpmHashAtom *t, *p;
int i;
unsigned int oldSize = size;
t = atomTable;
HASH_TABLE_GROWS
table->size = size;
table->limit = size / 3;
if (size >= UINT_MAX / sizeof(*atomTable))
return (XpmNoMemory);
atomTable = (xpmHashAtom *) XpmMalloc(size * sizeof(*atomTable));
if (!atomTable)
return (XpmNoMemory);
table->atomTable = atomTable;
for (p = atomTable + size; p > atomTable;)
*--p = NULL;
for (i = 0, p = t; i < oldSize; i++, p++)
if (*p) {
xpmHashAtom *ps = xpmHashSlot(table, (*p)->name);
*ps = *p;
}
XpmFree(t);
return (XpmSuccess);
}
/*
* xpmHashIntern(table, name, data)
* an xpmHashAtom is created if name doesn't exist, with the given data.
*/
int
xpmHashIntern(table, tag, data)
xpmHashTable *table;
char *tag;
void *data;
{
xpmHashAtom *slot;
if (!*(slot = xpmHashSlot(table, tag))) {
/* undefined, make a new atom with the given data */
if (!(*slot = AtomMake(tag, data)))
return (XpmNoMemory);
if (table->used >= table->limit) {
int ErrorStatus;
if ((ErrorStatus = HashTableGrows(table)) != XpmSuccess)
return (ErrorStatus);
table->used++;
return (XpmSuccess);
}
table->used++;
}
return (XpmSuccess);
}
/*
* must be called before allocating any atom
*/
int
xpmHashTableInit(table)
xpmHashTable *table;
{
xpmHashAtom *p;
xpmHashAtom *atomTable;
table->size = INITIAL_HASH_SIZE;
table->limit = table->size / 3;
table->used = 0;
if (table->size >= UINT_MAX / sizeof(*atomTable))
return (XpmNoMemory);
atomTable = (xpmHashAtom *) XpmMalloc(table->size * sizeof(*atomTable));
if (!atomTable)
return (XpmNoMemory);
for (p = atomTable + table->size; p > atomTable;)
*--p = NULL;
table->atomTable = atomTable;
return (XpmSuccess);
}
/*
* frees a hashtable and all the stored atoms
*/
void
xpmHashTableFree(table)
xpmHashTable *table;
{
xpmHashAtom *p;
xpmHashAtom *atomTable = table->atomTable;
if (!atomTable)
return;
for (p = atomTable + table->size; p > atomTable;)
if (*--p)
XpmFree(*p);
XpmFree(atomTable);
table->atomTable = NULL;
}
|
