80 lines
1.6 KiB
C
80 lines
1.6 KiB
C
/*
|
|
* Code adapted from uClibc-0.9.30.3
|
|
*
|
|
* It is therefore covered by the GNU LESSER GENERAL PUBLIC LICENSE
|
|
* Version 2.1, February 1999
|
|
*
|
|
* Wolfgang Denk <wd@denx.de>
|
|
*/
|
|
|
|
/* This code is derived from a public domain shell sort routine by
|
|
* Ray Gardner and found in Bob Stout's snippets collection. The
|
|
* original code is included below in an #if 0/#endif block.
|
|
*
|
|
* I modified it to avoid the possibility of overflow in the wgap
|
|
* calculation, as well as to reduce the generated code size with
|
|
* bcc and gcc. */
|
|
|
|
#include <linux/types.h>
|
|
#include <common.h>
|
|
#include <qsort.h>
|
|
|
|
void qsort(void *base,
|
|
size_t nel,
|
|
size_t width,
|
|
int (*comp)(const void *, const void *))
|
|
{
|
|
size_t wgap, i, j, k;
|
|
char tmp;
|
|
|
|
if (nel < 2 || width == 0)
|
|
return;
|
|
|
|
/* check for overflow */
|
|
if (nel > ((size_t)(-1)) / width)
|
|
return;
|
|
|
|
wgap = 0;
|
|
do {
|
|
wgap = 3 * wgap + 1;
|
|
} while (wgap < (nel - 1) / 3);
|
|
|
|
/*
|
|
* From the above, we know that either wgap == 1 < nel or
|
|
* ((wgap-1) / 3 < (int) ((nel - 1) / 3) <= (nel - 1) / 3 ==> wgap < nel.
|
|
*/
|
|
wgap *= width; /* So this can not overflow if wnel doesn't. */
|
|
nel *= width; /* Convert nel to 'wnel' */
|
|
do {
|
|
i = wgap;
|
|
do {
|
|
j = i;
|
|
do {
|
|
char *a;
|
|
char *b;
|
|
|
|
j -= wgap;
|
|
a = j + ((char *)base);
|
|
b = a + wgap;
|
|
|
|
if (comp(a, b) <= 0)
|
|
break;
|
|
|
|
k = width;
|
|
do {
|
|
tmp = *a;
|
|
*a++ = *b;
|
|
*b++ = tmp;
|
|
} while (--k);
|
|
} while (j >= wgap);
|
|
i += width;
|
|
} while (i < nel);
|
|
wgap = (wgap - width) / 3;
|
|
} while (wgap);
|
|
}
|
|
|
|
int strcmp_compar(const void *p1, const void *p2)
|
|
{
|
|
return strcmp((const char *)p1, (const char *)p2);
|
|
}
|