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31 /* #include <linux/string.h> */
34 * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
36 #define swapcode(TYPE, parmi, parmj, n) do { \
37 long i = (n) / sizeof (TYPE); \
38 register TYPE *pi = (TYPE *) (parmi); \
39 register TYPE *pj = (TYPE *) (parmj); \
41 register TYPE t = *pi; \
47 #define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \
48 es % sizeof(long) ? 2 : es == sizeof(long) ? 0 : 1;
51 swapfunc(char *a, char *b, int n, int swaptype)
54 swapcode(long, a, b, n);
56 swapcode(char, a, b, n);
59 #define yswap(a, b) do { \
60 if (swaptype == 0) { \
61 long t = *(long *)(a); \
62 *(long *)(a) = *(long *)(b); \
65 swapfunc(a, b, es, swaptype); \
68 #define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
70 static __inline char *
71 med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
73 return cmp(a, b) < 0 ?
74 (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a))
75 : (cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c));
79 #define min(a, b) (((a) < (b)) ? (a) : (b))
83 yaffs_qsort(void *aa, size_t n, size_t es,
84 int (*cmp)(const void *, const void *))
86 char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
87 int d, r, swaptype, swap_cnt;
88 register char *a = aa;
90 loop: SWAPINIT(a, es);
93 for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es)
94 for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
99 pm = (char *)a + (n / 2) * es;
102 pn = (char *)a + (n - 1) * es;
105 pl = med3(pl, pl + d, pl + 2 * d, cmp);
106 pm = med3(pm - d, pm, pm + d, cmp);
107 pn = med3(pn - 2 * d, pn - d, pn, cmp);
109 pm = med3(pl, pm, pn, cmp);
112 pa = pb = (char *)a + es;
114 pc = pd = (char *)a + (n - 1) * es;
116 while (pb <= pc && (r = cmp(pb, a)) <= 0) {
124 while (pb <= pc && (r = cmp(pc, a)) >= 0) {
139 if (swap_cnt == 0) { /* Switch to insertion sort */
140 for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es)
141 for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
147 pn = (char *)a + n * es;
148 r = min(pa - (char *)a, pb - pa);
149 vecswap(a, pb - r, r);
150 r = min((long)(pd - pc), (long)(pn - pd - es));
151 vecswap(pb, pn - r, r);
154 yaffs_qsort(a, r / es, es, cmp);
157 /* Iterate rather than recurse to save stack space */
162 /* yaffs_qsort(pn - r, r / es, es, cmp);*/