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/*
* This file lifted in toto from 'Dlibs' on the atari ST (RdeBath)
*
*
* Dale Schumacher 399 Beacon Ave.
* (alias: Dalnefre') St. Paul, MN 55104
* dal@syntel.UUCP United States of America
* "It's not reality that's important, but how you perceive things."
*/
#include <string.h>
char *_qbuf = 0; /* pointer to storage for qsort() */
#define PIVOT ((i+j)>>1)
#define moveitem(dst,src,size) if(dst != src) memcpy(dst, src, size)
static void _wqsort(base, lo, hi, cmp)
register int *base;
register int lo;
register int hi;
register int (*cmp) ();
{
int k;
register int i, j, t;
register int *p = &k;
while (hi > lo) {
i = lo;
j = hi;
t = PIVOT;
*p = base[t];
base[t] = base[i];
base[i] = *p;
while (i < j) {
while (((*cmp) ((base + j), p)) > 0)
--j;
base[i] = base[j];
while ((i < j) && (((*cmp) ((base + i), p)) <= 0))
++i;
base[j] = base[i];
}
base[i] = *p;
if ((i - lo) < (hi - i)) {
_wqsort(base, lo, (i - 1), cmp);
lo = i + 1;
} else {
_wqsort(base, (i + 1), hi, cmp);
hi = i - 1;
}
}
}
static void _lqsort(base, lo, hi, cmp)
register long *base;
register int lo;
register int hi;
register int (*cmp) ();
{
long k;
register int i, j, t;
register long *p = &k;
while (hi > lo) {
i = lo;
j = hi;
t = PIVOT;
*p = base[t];
base[t] = base[i];
base[i] = *p;
while (i < j) {
while (((*cmp) ((base + j), p)) > 0)
--j;
base[i] = base[j];
while ((i < j) && (((*cmp) ((base + i), p)) <= 0))
++i;
base[j] = base[i];
}
base[i] = *p;
if ((i - lo) < (hi - i)) {
_lqsort(base, lo, (i - 1), cmp);
lo = i + 1;
} else {
_lqsort(base, (i + 1), hi, cmp);
hi = i - 1;
}
}
}
static void _nqsort(base, lo, hi, size, cmp)
register char *base;
register int lo;
register int hi;
register int size;
register int (*cmp) ();
{
register int i, j;
register char *p = _qbuf;
while (hi > lo) {
i = lo;
j = hi;
p = (base + size * PIVOT);
moveitem(_qbuf, p, size);
moveitem(p, (base + size * i), size);
moveitem((base + size * i), _qbuf, size);
p = _qbuf;
while (i < j) {
while (((*cmp) ((base + size * j), p)) > 0)
--j;
moveitem((base + size * i), (base + size * j), size);
while ((i < j) && (((*cmp) ((base + size * i), p)) <= 0))
++i;
moveitem((base + size * j), (base + size * i), size);
}
moveitem((base + size * i), p, size);
if ((i - lo) < (hi - i)) {
_nqsort(base, lo, (i - 1), size, cmp);
lo = i + 1;
} else {
_nqsort(base, (i + 1), hi, size, cmp);
hi = i - 1;
}
}
}
extern int qsort(base, num, size, cmp)
char *base;
int num;
int size;
int (*cmp) ();
{
char _qtemp[128];
if (_qbuf == 0) {
if (size > sizeof(_qtemp)) /* records too large! */
return 1;
_qbuf = _qtemp;
}
if (size == 2)
_wqsort(base, 0, num - 1, cmp);
else if (size == 4)
_lqsort(base, 0, num - 1, cmp);
else
_nqsort(base, 0, num - 1, size, cmp);
if (_qbuf == _qtemp)
_qbuf = 0;
return 0;
}
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