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
|
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include "types.h"
#include "table.h"
// currently going with a binary lookup...
static inline int compare(struct string a, struct string b) {
size_t len;
if (a.len > b.len)
len = b.len;
else
len = a.len;
int val = memcmp(a.data, b.data, len);
if (val == 0 && a.len != b.len)
return 1;
else
return val;
}
static inline uint64_t search(struct table tbl, struct string name, uint8_t *exists) {
if (tbl.len == 0)
return 0;
size_t low = 0, high = tbl.len - 1;
size_t mid = high/2;
while (low != high) {
int val = compare(tbl.array[mid].name, name);
if (val == 0) {
*exists = 1;
return mid;
} else if (val > 0) {
low = mid + 1;
if (mid > low)
break;
if (low > high)
low = high;
} else {
high = mid - 1;
if (mid < high)
break;
if (high < low)
high = low;
}
mid = low + ((high-low)/2);
}
int val = compare(tbl.array[mid].name, name);
if (val > 0) {
*exists = 0;
return mid+1;
} else if (val == 0) {
*exists = 1;
return mid;
} else {
*exists = 0;
return mid;
}
}
int set_table_index(struct table *tbl, struct string name, void *ptr) {
uint8_t exists, err;
uint64_t index = search(*tbl, name, &exists);
if (index == tbl->len) {
void *tmp = realloc(tbl->array, sizeof(*(tbl->array)) * (tbl->len+1));
if (tmp == 0)
return 1;
tbl->array = tmp;
tbl->len++;
} else if (!exists) {
void *tmp = realloc(tbl->array, sizeof(*(tbl->array)) * (tbl->len+1));
if (tmp == 0)
return 1;
tbl->array = tmp;
memmove(&(tbl->array[index+1]), &(tbl->array[index]), (tbl->len - index) * sizeof(*(tbl->array)));
tbl->len++;
} else {
tbl->array[index].ptr = ptr;
return 0; // don't overwrite old allocated name
}
char *data = malloc(name.len);
if (data == 0)
return 1;
memcpy(data, name.data, name.len);
tbl->array[index] = (struct table_index){{data, name.len}, ptr};
return 0;
}
void * get_table_index(struct table tbl, struct string name) {
if (tbl.len == 0)
return 0;
size_t low = 0, high = tbl.len - 1;
size_t mid = high/2;
while (low != high) {
int val = compare(tbl.array[mid].name, name);
if (val == 0) {
return tbl.array[mid].ptr;
} else if (val > 0) {
low = mid + 1;
if (mid > low)
return 0;
if (low > high)
low = high;
} else {
high = mid - 1;
if (mid < high)
return 0;
if (high < low)
high = low;
}
mid = low + ((high-low)/2);
}
if (compare(tbl.array[mid].name, name) == 0)
return tbl.array[mid].ptr;
else
return 0;
}
void * remove_table_index(struct table *tbl, struct string name) {
uint8_t exists, err;
uint64_t index = search(*tbl, name, &exists);
if (!exists)
return 0;
void *ptr = tbl->array[index].ptr;
free(tbl->array[index].name.data);
memmove(&(tbl->array[index]), &(tbl->array[index+1]), (tbl->len - index) * sizeof(*(tbl->array)));
tbl->len--;
void *tmp = realloc(tbl->array, sizeof(*(tbl->array)) * tbl->len);
if (tmp)
tbl->array = tmp;
// else: realloc failed on shrinking... so now we have a table that's allocated a bit too big, not much of an issue
return ptr;
}
|
