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54c6977e
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1/*
2 * Code adapted from uClibc-0.9.30.3
3 *
4 * It is therefore covered by the GNU LESSER GENERAL PUBLIC LICENSE
5 * Version 2.1, February 1999
6 *
7 * Wolfgang Denk <wd@denx.de>
8 */
9
10/* This code is derived from a public domain shell sort routine by
11 * Ray Gardner and found in Bob Stout's snippets collection. The
12 * original code is included below in an #if 0/#endif block.
13 *
14 * I modified it to avoid the possibility of overflow in the wgap
15 * calculation, as well as to reduce the generated code size with
16 * bcc and gcc. */
17
f7ae49fc 18#include <log.h>
54c6977e 19#include <linux/types.h>
560d424b 20#include <exports.h>
8bef79bf 21#include <sort.h>
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22
23void qsort(void *base,
071bc923
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24 size_t nel,
25 size_t width,
26 int (*comp)(const void *, const void *))
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27{
28 size_t wgap, i, j, k;
29 char tmp;
30
31 if ((nel > 1) && (width > 0)) {
32 assert(nel <= ((size_t)(-1)) / width); /* check for overflow */
33 wgap = 0;
34 do {
35 wgap = 3 * wgap + 1;
36 } while (wgap < (nel-1)/3);
37 /* From the above, we know that either wgap == 1 < nel or */
38 /* ((wgap-1)/3 < (int) ((nel-1)/3) <= (nel-1)/3 ==> wgap < nel. */
39 wgap *= width; /* So this can not overflow if wnel doesn't. */
40 nel *= width; /* Convert nel to 'wnel' */
41 do {
42 i = wgap;
43 do {
44 j = i;
45 do {
46 register char *a;
47 register char *b;
48
49 j -= wgap;
50 a = j + ((char *)base);
51 b = a + wgap;
52 if ((*comp)(a, b) <= 0) {
53 break;
54 }
55 k = width;
56 do {
57 tmp = *a;
58 *a++ = *b;
59 *b++ = tmp;
60 } while (--k);
61 } while (j >= wgap);
62 i += width;
63 } while (i < nel);
64 wgap = (wgap - width)/3;
65 } while (wgap);
66 }
67}
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68
69int strcmp_compar(const void *p1, const void *p2)
70{
71 return strcmp(*(const char **)p1, *(const char **)p2);
72}