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/*
* qsort.c
*
* This is actually combsort. It's an O(n log n) algorithm with
* simplicity/small code size being its main virtue.
*/
#include <stddef.h>
#include <string.h>
static inline size_t newgap(size_t gap)
{
gap = (gap*10)/13;
if ( gap == 9 || gap == 10 )
gap = 11;
if ( gap < 1 )
gap = 1;
return gap;
}
void qsort(void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *))
{
size_t gap = nmemb;
size_t i, j;
char *p1, *p2;
int swapped;
do {
gap = newgap(gap);
swapped = 0;
for ( i = 0, p1 = base ; i < nmemb-gap ; i++, p1 += size ) {
j = i+gap;
if ( compar(p1, p2 = (char *)base+j*size) > 0 ) {
memswap(p1, p2, size);
swapped = 1;
}
}
} while ( gap > 1 || swapped );
}
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