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stdlib/FreeBSD/qsort.c /dev/null Libc-1669.0.4
--- /dev/null
+++ Libc/Libc-1669.0.4/stdlib/FreeBSD/qsort.c
@@ -0,0 +1,321 @@
+/*-
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)qsort.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef I_AM_QSORT_R
+typedef int		 cmp_t(void *, const void *, const void *);
+#else
+typedef int		 cmp_t(const void *, const void *);
+#endif
+static inline char	*med3(char *, char *, char *, cmp_t *, void *);
+static inline void	 swapfunc(char *, char *, size_t, int, int);
+
+#define	MIN(a, b)	((a) < (b) ? a : b)
+
+/*
+ * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
+ */
+#define	swapcode(TYPE, parmi, parmj, n) {		\
+	size_t i = (n) / sizeof (TYPE);			\
+	TYPE *pi = (TYPE *) (parmi);		\
+	TYPE *pj = (TYPE *) (parmj);		\
+	do { 						\
+		TYPE	t = *pi;		\
+		*pi++ = *pj;				\
+		*pj++ = t;				\
+	} while (--i > 0);				\
+}
+
+#define	SWAPINIT(TYPE, a, es) swaptype_ ## TYPE =	\
+	((char *)a - (char *)0) % sizeof(TYPE) ||	\
+	es % sizeof(TYPE) ? 2 : es == sizeof(TYPE) ? 0 : 1;
+
+static inline void
+swapfunc(char *a, char *b, size_t n, int swaptype_long, int swaptype_int)
+{
+	if (swaptype_long <= 1)
+		swapcode(long, a, b, n)
+	else if (swaptype_int <= 1)
+		swapcode(int, a, b, n)
+	else
+		swapcode(char, a, b, n)
+}
+
+#define	swap(a, b)					\
+	if (swaptype_long == 0) {			\
+		long t = *(long *)(a);			\
+		*(long *)(a) = *(long *)(b);		\
+		*(long *)(b) = t;			\
+	} else if (swaptype_int == 0) {			\
+		int t = *(int *)(a);			\
+		*(int *)(a) = *(int *)(b);		\
+		*(int *)(b) = t;			\
+	} else						\
+		swapfunc(a, b, es, swaptype_long, swaptype_int)
+
+#define	vecswap(a, b, n)				\
+	if ((n) > 0) swapfunc(a, b, n, swaptype_long, swaptype_int)
+
+#ifdef I_AM_QSORT_R
+#define	CMP(t, x, y) (cmp((t), (x), (y)))
+#else
+#define	CMP(t, x, y) (cmp((x), (y)))
+#endif
+
+/*
+ * Find the median of 3 elements
+ */
+static inline char *
+med3(char *a, char *b, char *c, cmp_t *cmp, void *thunk
+#ifndef I_AM_QSORT_R
+__unused
+#endif
+)
+{
+	return CMP(thunk, a, b) < 0 ?
+	       (CMP(thunk, b, c) < 0 ? b : (CMP(thunk, a, c) < 0 ? c : a ))
+	      :(CMP(thunk, b, c) > 0 ? b : (CMP(thunk, a, c) < 0 ? a : c ));
+}
+
+#ifdef __LP64__
+#define DEPTH(x)	(2 * (flsl((long)(x)) - 1))
+#else /* !__LP64__ */
+#define DEPTH(x)	(2 * (fls((int)(x)) - 1))
+#endif /* __LP64__ */
+
+#ifdef I_AM_QSORT_R
+int __heapsort_r(void *, size_t, size_t, void *, int (*)(void *, const void *, const void *));
+#endif
+
+/*
+ * Simple insertion sort routine.
+ */
+static bool
+_isort(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp, int swap_limit, int swaptype_long, int swaptype_int)
+{
+	int swap_cnt = 0;
+	for (char *pm = (char *)a + es; pm < (char *)a + n * es; pm += es) {
+		for (char *pl = pm; pl > (char *)a && CMP(thunk, pl - es, pl) > 0;
+				pl -= es) {
+			swap(pl, pl - es);
+			if (swap_limit && ++swap_cnt > swap_limit) return false;
+		}
+	}
+	return true;
+}
+
+#ifdef I_AM_QSORT_R
+static void
+_qsort(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp, int depth_limit)
+#else
+#define	thunk NULL
+static void
+_qsort(void *a, size_t n, size_t es, cmp_t *cmp, int depth_limit)
+#endif
+{
+	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+	size_t d1, d2;
+	int cmp_result;
+	int swaptype_long, swaptype_int, swap_cnt;
+
+loop:
+	SWAPINIT(long, a, es);
+	SWAPINIT(int, a, es);
+	swap_cnt = 0;
+
+	if (depth_limit-- <= 0) {
+		/*
+		 * We've hit our recursion limit, switch to heapsort
+		 */
+#ifdef I_AM_QSORT_R
+		__heapsort_r(a, n, es, thunk, cmp);
+#else
+		heapsort(a, n, es, cmp);
+#endif
+		return;
+	}
+
+	if (n <= 7) {
+		/*
+		 * For sufficiently small inputs, we'll just insertion sort.
+		 *
+		 * Pass 0 as swap limit, since this must complete.
+		 */
+		_isort(a, n, es, thunk, cmp, 0, swaptype_long, swaptype_int);
+		return;
+	}
+
+	/*
+	 * Compute the pseudomedian.  Small arrays use 3 samples, large ones use 9.
+	 */
+	pl = a;
+	pm = (char *)a + (n / 2) * es;
+	pn = (char *)a + (n - 1) * es;
+	if (n > 40) {
+		size_t d = (n / 8) * es;
+
+		pl = med3(pl, pl + d, pl + 2 * d, cmp, thunk);
+		pm = med3(pm - d, pm, pm + d, cmp, thunk);
+		pn = med3(pn - 2 * d, pn - d, pn, cmp, thunk);
+	}
+	pm = med3(pl, pm, pn, cmp, thunk);
+
+	/*
+	 * Pull the median to the front, starting us with:
+	 *
+	 * +-+-------------+
+	 * |=|      ?      |
+	 * +-+-------------+
+	 * a pa,pb         pc,pd
+	 */
+	swap(a, pm);
+	pa = pb = (char *)a + es;
+	pc = pd = (char *)a + (n - 1) * es;
+
+	for (;;) {
+		/*
+		 * - Move b forward while it's less than the median
+		 * - Move c backwards while it's greater than the median
+		 * - When equal to the median, swap to the outside
+		 */
+		while (pb <= pc && (cmp_result = CMP(thunk, pb, a)) <= 0) {
+			if (cmp_result == 0) {
+				swap_cnt = 1;
+				swap(pa, pb);
+				pa += es;
+			}
+			pb += es;
+		}
+		while (pb <= pc && (cmp_result = CMP(thunk, pc, a)) >= 0) {
+			if (cmp_result == 0) {
+				swap_cnt = 1;
+				swap(pc, pd);
+				pd -= es;
+			}
+			pc -= es;
+		}
+		if (pb > pc)
+			break;
+		swap(pb, pc);
+		swap_cnt = 1;
+		pb += es;
+		pc -= es;
+	}
+
+	/*
+	 * Now we've got:
+	 *
+	 * +---+-----+-----+---+
+	 * | = |  <  |  >  | = |
+	 * +---+-----+-----+---+
+	 * a   pa  pc,pb   pd  pn
+	 *
+	 * So swap the '=' into the middle
+	 */
+
+	pn = (char *)a + n * es;
+	d1 = MIN(pa - (char *)a, pb - pa);
+	vecswap(a, pb - d1, d1);
+	d1 = MIN(pd - pc, pn - pd - es);
+	vecswap(pb, pn - d1, d1);
+
+	/*
+	 * +-----+---+---+-----+
+	 * |  <  |   =   |  >  |
+	 * +-----+---+---+-----+
+	 * a                   pn
+	 */
+
+	if (swap_cnt == 0) {  /* Switch to insertion sort */
+		int r = 1 + n / 4; /* n > 7, so r >= 2 */
+		if (!_isort(a, n, es, thunk, cmp, r, swaptype_long, swaptype_int)) {
+			goto nevermind;
+		}
+		return;
+	}
+nevermind:
+
+	d1 = pb - pa;
+	d2 = pd - pc;
+	if (d1 <= d2) {
+		/* Recurse on left partition, then iterate on right partition */
+		if (d1 > es) {
+#ifdef I_AM_QSORT_R
+			_qsort(a, d1 / es, es, thunk, cmp, depth_limit);
+#else
+			_qsort(a, d1 / es, es, cmp, depth_limit);
+#endif
+		}
+		if (d2 > es) {
+			/* Iterate rather than recurse to save stack space */
+			/* qsort(pn - d2, d2 / es, es, cmp); */
+			a = pn - d2;
+			n = d2 / es;
+			goto loop;
+		}
+	} else {
+		/* Recurse on right partition, then iterate on left partition */
+		if (d2 > es) {
+#ifdef I_AM_QSORT_R
+			_qsort(pn - d2, d2 / es, es, thunk, cmp, depth_limit);
+#else
+			_qsort(pn - d2, d2 / es, es, cmp, depth_limit);
+#endif
+		}
+		if (d1 > es) {
+			/* Iterate rather than recurse to save stack space */
+			/* qsort(a, d1 / es, es, cmp); */
+			n = d1 / es;
+			goto loop;
+		}
+	}
+}
+
+void
+#ifdef I_AM_QSORT_R
+qsort_r(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp)
+#else
+qsort(void *a, size_t n, size_t es, cmp_t *cmp)
+#endif
+{
+	_qsort(a, n, es,
+#ifdef I_AM_QSORT_R
+		thunk,
+#endif
+		cmp, DEPTH(n));
+}