blob: 09224f21dbbfd3d20f8c84b73f4662922d7d008f (
plain)
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
|
#include "global.h"
typedef struct chunk {
struct chunk *next;
char *limit;
char *avail;
} Chunk;
static Chunk first = { NULL, NULL, NULL };
static Chunk *arena = &first;
void *arena_getmem(n)
size_t n;
{
char *q;
char *p = arena->avail;
n = (n + 7) & ~7; /* ensuring alignment to 8 bytes */
q = p + n;
if (q <= arena->limit) {
arena->avail = q;
return p;
}
{
Chunk *ap = arena;
Chunk *np = ap->next;
while (np) {
char *v = sizeof(Chunk) + (char *) np;
if (v + n <= np->limit) {
np->avail = v + n;
arena = np;
return v;
}
ap = np;
np = ap->next;
}
{
size_t m = n + 10000;
np = (Chunk *) malloc(m);
np->limit = m + (char *) np;
np->avail = n + sizeof(Chunk) + (char *) np;
np->next = NULL;
ap->next = np;
arena = np;
return sizeof(Chunk) + (char *) np;
}
}
}
void arena_free()
{
arena = &first;
}
|
