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
|
/*
* Copyright (c) 2003-2010 Alexandre Ratchov <alex@caoua.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* a pool is a large memory block (the pool) that is split into
* small blocks of equal size (pools entries). Its used for
* fast allocation of pool entries. Free enties are on a singly
* linked list
*/
#include "utils.h"
#include "pool.h"
unsigned pool_debug = 0;
/*
* initialises a pool of "itemnum" elements of size "itemsize"
*/
void
pool_init(struct pool *o, char *name, unsigned itemsize, unsigned itemnum)
{
unsigned i;
unsigned char *p;
/*
* round item size to sizeof unsigned
*/
if (itemsize < sizeof(struct poolent)) {
itemsize = sizeof(struct poolent);
}
itemsize += sizeof(unsigned) - 1;
itemsize &= ~(sizeof(unsigned) - 1);
o->data = xmalloc(itemsize * itemnum, "pool");
if (!o->data) {
log_puts("pool_init(");
log_puts(name);
log_puts("): out of memory\n");
panic();
}
o->first = NULL;
o->itemsize = itemsize;
o->itemnum = itemnum;
o->name = name;
#ifdef POOL_DEBUG
o->maxused = 0;
o->used = 0;
o->newcnt = 0;
#endif
/*
* create a linked list of all entries
*/
p = o->data;
for (i = itemnum; i != 0; i--) {
((struct poolent *)p)->next = o->first;
o->first = (struct poolent *)p;
p += itemsize;
o->itemnum++;
}
}
/*
* free the given pool
*/
void
pool_done(struct pool *o)
{
xfree(o->data);
#ifdef POOL_DEBUG
if (o->used != 0) {
log_puts("pool_done(");
log_puts(o->name);
log_puts("): WARNING ");
log_putu(o->used);
log_puts(" items still allocated\n");
}
if (pool_debug) {
log_puts("pool_done(");
log_puts(o->name);
log_puts("): using ");
log_putu((1023 + o->itemnum * o->itemsize) / 1024);
log_puts("kB maxused = ");
log_putu(100 * o->maxused / o->itemnum);
log_puts("% allocs = ");
log_putu(100 * o->newcnt / o->itemnum);
log_puts("%\n");
}
#endif
}
/*
* allocate an entry from the pool: just unlink
* it from the free list and return the pointer
*/
void *
pool_new(struct pool *o)
{
#ifdef POOL_DEBUG
unsigned i;
unsigned char *buf;
#endif
struct poolent *e;
if (!o->first) {
log_puts("pool_new(");
log_puts(o->name);
log_puts("): pool is empty\n");
panic();
}
/*
* unlink from the free list
*/
e = o->first;
o->first = e->next;
#ifdef POOL_DEBUG
o->newcnt++;
o->used++;
if (o->used > o->maxused)
o->maxused = o->used;
/*
* overwrite the entry with garbage so any attempt to use
* uninitialized memory will probably segfault
*/
buf = (unsigned char *)e;
for (i = o->itemsize; i > 0; i--)
*(buf++) = 0xd0;
#endif
return e;
}
/*
* free an entry: just link it again on the free list
*/
void
pool_del(struct pool *o, void *p)
{
struct poolent *e = (struct poolent *)p;
#ifdef POOL_DEBUG
unsigned i;
unsigned char *buf;
/*
* check if we aren't trying to free more
* entries than the poll size
*/
if (o->used == 0) {
log_puts("pool_del(");
log_puts(o->name);
log_puts("): pool is full\n");
panic();
}
o->used--;
/*
* overwrite the entry with garbage so any attempt to use a
* free entry will probably segfault
*/
buf = (unsigned char *)e;
for (i = o->itemsize; i > 0; i--)
*(buf++) = 0xdf;
#endif
/*
* link on the free list
*/
e->next = o->first;
o->first = e;
}
|
