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
|
/* Copyright (C) 2000 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* Quick & light hash implementation for tab completion purposes
*
* by Andi Gutmans <andi@zend.com>
* and Zeev Suraski <zeev@zend.com>
* Small portability changes by Monty. Changed also to use my_malloc/my_free
*/
#include <my_global.h>
#include <m_string.h>
#include <my_sys.h>
#include "completion_hash.h"
uint hashpjw(const char *arKey, uint nKeyLength)
{
uint h = 0, g, i;
for (i = 0; i < nKeyLength; i++) {
h = (h << 4) + arKey[i];
if ((g = (h & 0xF0000000))) {
h = h ^ (g >> 24);
h = h ^ g;
}
}
return h;
}
int completion_hash_init(HashTable *ht, uint nSize)
{
ht->arBuckets = (Bucket **) my_malloc(nSize* sizeof(Bucket *),
MYF(MY_ZEROFILL | MY_WME));
if (!ht->arBuckets)
{
ht->initialized = 0;
return FAILURE;
}
init_alloc_root(&ht->mem_root, 8192, 0);
ht->pHashFunction = hashpjw;
ht->nTableSize = nSize;
ht->initialized = 1;
return SUCCESS;
}
int completion_hash_update(HashTable *ht, char *arKey, uint nKeyLength,
char *str)
{
uint h, nIndex;
Bucket *p;
h = ht->pHashFunction(arKey, nKeyLength);
nIndex = h % ht->nTableSize;
if (nKeyLength <= 0) {
return FAILURE;
}
p = ht->arBuckets[nIndex];
while (p)
{
if ((p->h == h) && (p->nKeyLength == nKeyLength)) {
if (!memcmp(p->arKey, arKey, nKeyLength)) {
entry *n;
if (!(n = (entry *) alloc_root(&ht->mem_root,sizeof(entry))))
return FAILURE;
n->pNext = p->pData;
n->str = str;
p->pData = n;
p->count++;
return SUCCESS;
}
}
p = p->pNext;
}
if (!(p = (Bucket *) alloc_root(&ht->mem_root, sizeof(Bucket))))
return FAILURE;
p->arKey = arKey;
p->nKeyLength = nKeyLength;
p->h = h;
if (!(p->pData = (entry*) alloc_root(&ht->mem_root, sizeof(entry))))
return FAILURE;
p->pData->str = str;
p->pData->pNext = 0;
p->count = 1;
p->pNext = ht->arBuckets[nIndex];
ht->arBuckets[nIndex] = p;
return SUCCESS;
}
static Bucket *completion_hash_find(HashTable *ht, const char *arKey,
uint nKeyLength)
{
uint h, nIndex;
Bucket *p;
h = ht->pHashFunction(arKey, nKeyLength);
nIndex = h % ht->nTableSize;
p = ht->arBuckets[nIndex];
while (p)
{
if ((p->h == h) && (p->nKeyLength == nKeyLength)) {
if (!memcmp(p->arKey, arKey, nKeyLength)) {
return p;
}
}
p = p->pNext;
}
return (Bucket*) 0;
}
int completion_hash_exists(HashTable *ht, char *arKey, uint nKeyLength)
{
uint h, nIndex;
Bucket *p;
h = ht->pHashFunction(arKey, nKeyLength);
nIndex = h % ht->nTableSize;
p = ht->arBuckets[nIndex];
while (p)
{
if ((p->h == h) && (p->nKeyLength == nKeyLength))
{
if (!strcmp(p->arKey, arKey)) {
return 1;
}
}
p = p->pNext;
}
return 0;
}
Bucket *find_all_matches(HashTable *ht, const char *str, uint length,
uint *res_length)
{
Bucket *b;
b = completion_hash_find(ht,str,length);
if (!b) {
*res_length = 0;
return (Bucket*) 0;
} else {
*res_length = length;
return b;
}
}
Bucket *find_longest_match(HashTable *ht, char *str, uint length,
uint *res_length)
{
Bucket *b,*return_b;
char *s;
uint count;
uint lm;
b = completion_hash_find(ht,str,length);
if (!b) {
*res_length = 0;
return (Bucket*) 0;
}
count = b->count;
lm = length;
s = b->pData->str;
return_b = b;
while (s[lm]!=0 && (b=completion_hash_find(ht,s,lm+1))) {
if (b->count<count) {
*res_length=lm;
return return_b;
}
return_b=b;
lm++;
}
*res_length=lm;
return return_b;
}
void completion_hash_clean(HashTable *ht)
{
free_root(&ht->mem_root,MYF(0));
bzero((char*) ht->arBuckets,ht->nTableSize*sizeof(Bucket *));
}
void completion_hash_free(HashTable *ht)
{
completion_hash_clean(ht);
my_free(ht->arBuckets);
}
void add_word(HashTable *ht,char *str)
{
int i;
char *pos=str;
for (i=1; *pos; i++, pos++)
completion_hash_update(ht, str, i, str);
}
|
