/*
 * qsort
 * This function is exactly as documented in the BDS C Version
 * 1.5 Users Manual and as swiped from K & P.
 */

#define	MAX_QSORT_WIDTH	513	/* Largest object qsort can sort */

qsort(base, nel, width, compar)
char *base; int (*compar)();
unsigned width,nel;
{	int i, j;
	unsigned gap, ngap, t1;
	int jd, t2;

	t1 = nel * width;
	for (ngap = nel / 2; ngap > 0; ngap /= 2) {
	   gap = ngap * width;
	   t2 = gap + width;
	   jd = base + gap;
	   for (i = t2; i <= t1; i += width)
	      for (j =  i - t2; j >= 0; j -= gap) {
		if ((*compar)(base+j, jd+j) <=0) break;
			 _swp(width, base+j, jd+j);
	      }
	}
}

_swp(w,a,b)
char *a,*b;
unsigned w;
{
	char swapbuf[MAX_QSORT_WIDTH];
	movmem(a,swapbuf,w);
	movmem(b,a,w);
	movmem(swapbuf,b,w);
}