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
|
#include <stdint.h>
#include <sail_alloc.h>
#include <sail_spinlock.h>
#include <sail_arena.h>
static unsigned char *sail_arena_buffer;
static size_t sail_arena_length;
static size_t sail_arena_offset;
static struct sail_spinlock sail_arena_lock;
void sail_arena_init(void *buffer, size_t length)
{
sail_arena_buffer = buffer;
sail_arena_length = length;
sail_arena_offset = 0;
sail_spin_init(&sail_arena_lock);
}
void sail_arena_reset(void)
{
sail_spin_lock(&sail_arena_lock);
sail_arena_offset = 0;
sail_spin_unlock(&sail_arena_lock);
}
void *sail_malloc_align(size_t size, uintptr_t align)
{
sail_spin_lock(&sail_arena_lock);
uintptr_t offset = (uintptr_t)sail_arena_buffer + (uintptr_t)sail_arena_offset;
uintptr_t modulo = offset & (align - 1);
if (modulo != 0) {
offset += align - modulo;
}
offset -= (uintptr_t)sail_arena_buffer;
if (offset + size <= sail_arena_length) {
void *ptr = &sail_arena_buffer[offset];
sail_arena_offset = offset + size;
sail_spin_unlock(&sail_arena_lock);
return ptr;
}
sail_spin_unlock(&sail_arena_lock);
return NULL;
}
#ifndef SAIL_ARENA_ALIGNMENT
#define SAIL_ARENA_ALIGNMENT 4
#endif
void *sail_malloc(size_t size)
{
return sail_malloc_align(size, SAIL_ARENA_ALIGNMENT);
}
void *sail_realloc(void *ptr, size_t new_size)
{
return sail_malloc_align(new_size, SAIL_ARENA_ALIGNMENT);
}
void sail_free(void *ptr) {}
|
