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
|
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sort.h>
#include <linux/slab.h>
static void u32_swap(void *a, void *b, int size)
{
u32 t = *(u32 *)a;
*(u32 *)a = *(u32 *)b;
*(u32 *)b = t;
}
static void generic_swap(void *a, void *b, int size)
{
char t;
do {
t = *(char *)a;
*(char *)a++ = *(char *)b;
*(char *)b++ = t;
} while (--size > 0);
}
void sort(void *base, size_t num, size_t size,
int (*cmp_func)(const void *, const void *),
void (*swap_func)(void *, void *, int size))
{
int i = (num/2 - 1) * size, n = num * size, c, r;
if (!swap_func)
swap_func = (size == 4 ? u32_swap : generic_swap);
for ( ; i >= 0; i -= size) {
for (r = i; r * 2 + size < n; r = c) {
c = r * 2 + size;
if (c < n - size &&
cmp_func(base + c, base + c + size) < 0)
c += size;
if (cmp_func(base + r, base + c) >= 0)
break;
swap_func(base + r, base + c, size);
}
}
for (i = n - size; i > 0; i -= size) {
swap_func(base, base + i, size);
for (r = 0; r * 2 + size < i; r = c) {
c = r * 2 + size;
if (c < i - size &&
cmp_func(base + c, base + c + size) < 0)
c += size;
if (cmp_func(base + r, base + c) >= 0)
break;
swap_func(base + r, base + c, size);
}
}
}
EXPORT_SYMBOL(sort);
#if 0
int cmpint(const void *a, const void *b)
{
return *(int *)a - *(int *)b;
}
static int sort_test(void)
{
int *a, i, r = 1;
a = kmalloc(1000 * sizeof(int), GFP_KERNEL);
BUG_ON(!a);
printk("testing sort()\n");
for (i = 0; i < 1000; i++) {
r = (r * 725861) % 6599;
a[i] = r;
}
sort(a, 1000, sizeof(int), cmpint, NULL);
for (i = 0; i < 999; i++)
if (a[i] > a[i+1]) {
printk("sort() failed!\n");
break;
}
kfree(a);
return 0;
}
module_init(sort_test);
#endif
|