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
|
/*
* Copyright (C) 2001 Sistina Software
*
* This file is released under the LGPL.
*/
#include "dbg_malloc.h"
#include "hash.h"
#include "log.h"
struct hash_node {
struct hash_node *next;
void *data;
char key[1];
};
struct hash_table {
int num_nodes;
int num_slots;
struct hash_node **slots;
};
/* Permutation of the Integers 0 through 255 */
static unsigned char _nums[] = {
1, 14,110, 25, 97,174,132,119,138,170,125,118, 27,233,140, 51,
87,197,177,107,234,169, 56, 68, 30, 7,173, 73,188, 40, 36, 65,
49,213,104,190, 57,211,148,223, 48,115, 15, 2, 67,186,210, 28,
12,181,103, 70, 22, 58, 75, 78,183,167,238,157,124,147,172,144,
176,161,141, 86, 60, 66,128, 83,156,241, 79, 46,168,198, 41,254,
178, 85,253,237,250,154,133, 88, 35,206, 95,116,252,192, 54,221,
102,218,255,240, 82,106,158,201, 61, 3, 89, 9, 42,155,159, 93,
166, 80, 50, 34,175,195,100, 99, 26,150, 16,145, 4, 33, 8,189,
121, 64, 77, 72,208,245,130,122,143, 55,105,134, 29,164,185,194,
193,239,101,242, 5,171,126, 11, 74, 59,137,228,108,191,232,139,
6, 24, 81, 20,127, 17, 91, 92,251,151,225,207, 21, 98,113,112,
84,226, 18,214,199,187, 13, 32, 94,220,224,212,247,204,196, 43,
249,236, 45,244,111,182,153,136,129, 90,217,202, 19,165,231, 71,
230,142, 96,227, 62,179,246,114,162, 53,160,215,205,180, 47,109,
44, 38, 31,149,135, 0,216, 52, 63, 23, 37, 69, 39,117,146,184,
163,200,222,235,248,243,219, 10,152,131,123,229,203, 76,120,209
};
static struct hash_node *_create_node(const char *str)
{
/* remember sizeof(n) includes an extra char from key[1],
so not adding 1 to the strlen as you would expect */
struct hash_node *n = dbg_malloc(sizeof(*n) + strlen(str));
if (n)
strcpy(n->key, str);
return n;
}
static unsigned _hash(const char *str)
{
unsigned long int h = 0, g;
while (*str) {
h <<= 4;
h += _nums[(int) *str++];
g = h & ((unsigned long) 0xf << 16u);
if (g) {
h ^= g >> 16u;
h ^= g >> 5u;
}
}
return h;
}
struct hash_table *hash_create(unsigned size_hint)
{
size_t len;
unsigned new_size = 16u;
struct hash_table *hc = dbg_malloc(sizeof(*hc));
if (!hc) {
stack;
return 0;
}
memset(hc, 0, sizeof(*hc));
/* round size hint up to a power of two */
while (new_size < size_hint)
new_size = new_size << 1;
hc->num_slots = new_size;
len = sizeof(*(hc->slots)) * new_size;
if (!(hc->slots = dbg_malloc(len))) {
stack;
goto bad;
}
memset(hc->slots, 0, len);
return hc;
bad:
dbg_free(hc->slots);
dbg_free(hc);
return 0;
}
static void _free_nodes(struct hash_table *t)
{
struct hash_node *c, *n;
int i;
for (i = 0; i < t->num_slots; i++)
for (c = t->slots[i]; c; c = n) {
n = c->next;
dbg_free(c);
}
}
void hash_destroy(struct hash_table *t)
{
_free_nodes(t);
dbg_free(t->slots);
dbg_free(t);
}
static inline struct hash_node **_find(struct hash_table *t, const char *key)
{
unsigned h = _hash(key) & (t->num_slots - 1);
struct hash_node **c;
for(c = &t->slots[h]; *c; c = &((*c)->next))
if(!strcmp(key, (*c)->key))
break;
return c;
}
void *hash_lookup(struct hash_table *t, const char *key)
{
struct hash_node **c = _find(t, key);
return *c ? (*c)->data : 0;
}
int hash_insert(struct hash_table *t, const char *key, void *data)
{
struct hash_node **c = _find(t, key);
if(*c)
(*c)->data = data;
else {
struct hash_node *n = _create_node(key);
if (!n)
return 0;
n->data = data;
n->next = 0;
*c = n;
t->num_nodes++;
}
return 1;
}
void hash_remove(struct hash_table *t, const char *key)
{
struct hash_node **c = _find(t, key);
if (*c) {
struct hash_node *old = *c;
*c = (*c)->next;
dbg_free(old);
t->num_nodes--;
}
}
unsigned hash_get_num_entries(struct hash_table *t)
{
return t->num_nodes;
}
void hash_iter(struct hash_table *t, iterate_fn f)
{
struct hash_node *c;
int i;
for (i = 0; i < t->num_slots; i++)
for (c = t->slots[i]; c; c = c->next)
f(c->data);
}
void hash_wipe(struct hash_table *t)
{
_free_nodes(t);
memset(t->slots, 0, sizeof(struct hash_node *) * t->num_slots);
t->num_nodes = 0;
}
char *hash_get_key(struct hash_table *t, struct hash_node *n)
{
return n->key;
}
void *hash_get_data(struct hash_table *t, struct hash_node *n)
{
return n->data;
}
static struct hash_node *_next_slot(struct hash_table *t, unsigned int s)
{
struct hash_node *c = NULL;
int i;
for (i = s; i < t->num_slots && !c; i++)
c = t->slots[i];
return c;
}
struct hash_node *hash_get_first(struct hash_table *t)
{
return _next_slot(t, 0);
}
struct hash_node *hash_get_next(struct hash_table *t, struct hash_node *n)
{
unsigned int h = _hash(n->key) & (t->num_slots - 1);
return n->next ? n->next : _next_slot(t, h + 1);
}
|
