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--- Libc/Libc-1725.40.4/stdlib/FreeBSD/qsort.c
+++ /dev/null
@@ -1,321 +0,0 @@
-/*-
- * 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));
-}