[apple/xnu.git] / bsd / kern / qsort.c

/*
 * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 *
 *	@(#)qsort.c	8.1 (Berkeley) 6/4/93
 */


#include <sys/types.h>
//#include <stdlib.h>
#include <sys/kpi_private.h>

__private_extern__
void
qsort(void *a, size_t n, size_t es, int (*cmp)(const void *, const void *));

static inline char      *med3(char *, char *, char *, int (*)(const void *, const void *));
static inline void       swapfunc(char *, char *, long, 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)                 \
	long 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(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \
	es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;

static inline void
swapfunc(char *a, char *b, long n, int swaptype)
{
	if (swaptype <= 1) {
		swapcode(long, a, b, n);
	} else {
		swapcode(char, a, b, n);
	}
}

#define swap(a, b)                                      \
	if (swaptype == 0) {                            \
	        long t = *(long *)(a);                  \
	        *(long *)(a) = *(long *)(b);            \
	        *(long *)(b) = t;                       \
	} else                                          \
	        swapfunc(a, b, es, swaptype)

#define vecswap(a, b, n)        if ((n) > 0) swapfunc(a, b, n, swaptype)

static inline char *
med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
{
	return cmp(a, b) < 0 ?
	       (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a))
	       :(cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c));
}

__private_extern__
void
qsort(void *a, size_t n, size_t es, int (*cmp)(const void *, const void *))
{
	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
	int swaptype, swap_cnt;
	long d, r;

loop:   SWAPINIT(a, es);
	swap_cnt = 0;
	if (n < 7) {
		for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es) {
			for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
			    pl -= es) {
				swap(pl, (char *)(pl - es));
			}
		}
		return;
	}
	pm = (char *)a + (n / 2) * es;
	if (n > 7) {
		pl = a;
		pn = (char *)a + (n - 1) * es;
		if (n > 40) {
			d = (n / 8) * es;
			pl = med3(pl, pl + d, pl + 2 * d, cmp);
			pm = med3(pm - d, pm, pm + d, cmp);
			pn = med3(pn - 2 * d, pn - d, pn, cmp);
		}
		pm = med3(pl, pm, pn, cmp);
	}
	swap(a, pm);
	pa = pb = (char *)a + es;

	pc = pd = (char *)a + (n - 1) * es;
	for (;;) {
		while (pb <= pc && (r = cmp(pb, a)) <= 0) {
			if (r == 0) {
				swap_cnt = 1;
				swap(pa, pb);
				pa += es;
			}
			pb += es;
		}
		while (pb <= pc && (r = cmp(pc, a)) >= 0) {
			if (r == 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;
	}
	if (swap_cnt == 0) {  /* Switch to insertion sort */
		for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es) {
			for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
			    pl -= es) {
				swap(pl, pl - es);
			}
		}
		return;
	}

	pn = (char *)a + n * es;
	r = min(pa - (char *)a, pb - pa);
	vecswap(a, pb - r, r);
	r = min(pd - pc, pn - pd - es);
	vecswap(pb, pn - r, r);
	if ((size_t)(r = pb - pa) > es) {
		qsort(a, r / es, es, cmp);
	}
	if ((size_t)(r = pd - pc) > es) {
		/* Iterate rather than recurse to save stack space */
		a = pn - r;
		n = r / es;
		goto loop;
	}
/*		qsort(pn - r, r / es, es, cmp);*/
}

/* private KPI */
void
kx_qsort(void *array, size_t nm, size_t member_size, int (*cmpf)(const void *, const void *))
{
	qsort(array, nm, member_size, cmpf);
}
Commit	Line	Data
1c79356b	1	/*
2d21ac55	2	* Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
5d5c5d0d	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
f427ee49	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
f427ee49	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
2d21ac55 A	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
f427ee49	17	*
2d21ac55 A	18	* The Original Code and all software distributed under the License are
2d21ac55 A	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
f427ee49	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
	30	*
	31	* Copyright (c) 1992, 1993
	32	* The Regents of the University of California. All rights reserved.
	33	*
	34	* Redistribution and use in source and binary forms, with or without
	35	* modification, are permitted provided that the following conditions
	36	* are met:
	37	* 1. Redistributions of source code must retain the above copyright
	38	* notice, this list of conditions and the following disclaimer.
	39	* 2. Redistributions in binary form must reproduce the above copyright
	40	* notice, this list of conditions and the following disclaimer in the
	41	* documentation and/or other materials provided with the distribution.
	42	* 3. All advertising materials mentioning features or use of this software
	43	* must display the following acknowledgement:
	44	* This product includes software developed by the University of
	45	* California, Berkeley and its contributors.
	46	* 4. Neither the name of the University nor the names of its contributors
	47	* may be used to endorse or promote products derived from this software
	48	* without specific prior written permission.
	49	*
	50	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	51	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	52	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	53	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	54	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	55	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	56	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	57	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	58	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	59	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	60	* SUCH DAMAGE.
	61	*
	62	* @(#)qsort.c 8.1 (Berkeley) 6/4/93
	63	*/
	64
	65
	66	#include <sys/types.h>
b4c24cb9	67	//#include <stdlib.h>
3e170ce0	68	#include <sys/kpi_private.h>
b0d623f7 A	69
	70	__private_extern__
	71	void
	72	qsort(void a, size_t n, size_t es, int (cmp)(const void , const void ));
1c79356b	73
f427ee49 A	74	static inline char med3(char , char , char , int ()(const void , const void *));
f427ee49 A	75	static inline void swapfunc(char , char , long, int);
1c79356b	76
f427ee49	77	#define min(a, b) ((a) < (b) ? (a) : (b))
1c79356b A	78
	79	/*
	80	* Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
	81	*/
f427ee49 A	82	#define swapcode(TYPE, parmi, parmj, n) \
	83	long i = (n) / sizeof (TYPE); \
	84	TYPE pi = (TYPE ) (parmi); \
	85	TYPE pj = (TYPE ) (parmj); \
	86	do { \
	87	TYPE t = *pi; \
	88	pi++ = pj; \
	89	*pj++ = t; \
	90	} while (--i > 0);
1c79356b A	91
	92	#define SWAPINIT(a, es) swaptype = ((char )a - (char )0) % sizeof(long) \|\| \
	93	es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;
	94
	95	static inline void
f427ee49	96	swapfunc(char a, char b, long n, int swaptype)
1c79356b	97	{
f427ee49 A	98	if (swaptype <= 1) {
	99	swapcode(long, a, b, n);
	100	} else {
	101	swapcode(char, a, b, n);
	102	}
1c79356b A	103	}
1c79356b A	104
f427ee49 A	105	#define swap(a, b) \
	106	if (swaptype == 0) { \
	107	long t = (long )(a); \
	108	(long )(a) = (long )(b); \
	109	(long )(b) = t; \
	110	} else \
	111	swapfunc(a, b, es, swaptype)
1c79356b	112
f427ee49	113	#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
1c79356b A	114
1c79356b A	115	static inline char *
2d21ac55	116	med3(char a, char b, char c, int (cmp)(const void , const void ))
1c79356b A	117	{
1c79356b A	118	return cmp(a, b) < 0 ?
f427ee49 A	119	(cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a))
f427ee49 A	120	:(cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c));
1c79356b A	121	}
1c79356b A	122
b4c24cb9	123	__private_extern__
1c79356b	124	void
2d21ac55	125	qsort(void a, size_t n, size_t es, int (cmp)(const void , const void ))
1c79356b A	126	{
1c79356b A	127	char pa, pb, pc, pd, pl, pm, *pn;
f427ee49 A	128	int swaptype, swap_cnt;
f427ee49 A	129	long d, r;
1c79356b	130
f427ee49	131	loop: SWAPINIT(a, es);
1c79356b A	132	swap_cnt = 0;
1c79356b A	133	if (n < 7) {
f427ee49	134	for (pm = (char )a + es; pm < (char ) a + n * es; pm += es) {
1c79356b	135	for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
f427ee49 A	136	pl -= es) {
	137	swap(pl, (char *)(pl - es));
	138	}
	139	}
1c79356b A	140	return;
1c79356b A	141	}
55e303ae	142	pm = (char )a + (n / 2) es;
1c79356b A	143	if (n > 7) {
1c79356b A	144	pl = a;
55e303ae	145	pn = (char )a + (n - 1) es;
1c79356b A	146	if (n > 40) {
	147	d = (n / 8) * es;
	148	pl = med3(pl, pl + d, pl + 2 * d, cmp);
	149	pm = med3(pm - d, pm, pm + d, cmp);
	150	pn = med3(pn - 2 * d, pn - d, pn, cmp);
	151	}
	152	pm = med3(pl, pm, pn, cmp);
	153	}
	154	swap(a, pm);
55e303ae	155	pa = pb = (char *)a + es;
1c79356b	156
55e303ae	157	pc = pd = (char )a + (n - 1) es;
1c79356b A	158	for (;;) {
	159	while (pb <= pc && (r = cmp(pb, a)) <= 0) {
	160	if (r == 0) {
	161	swap_cnt = 1;
	162	swap(pa, pb);
	163	pa += es;
	164	}
	165	pb += es;
	166	}
	167	while (pb <= pc && (r = cmp(pc, a)) >= 0) {
	168	if (r == 0) {
	169	swap_cnt = 1;
	170	swap(pc, pd);
	171	pd -= es;
	172	}
	173	pc -= es;
	174	}
f427ee49	175	if (pb > pc) {
1c79356b	176	break;
f427ee49	177	}
1c79356b A	178	swap(pb, pc);
	179	swap_cnt = 1;
	180	pb += es;
	181	pc -= es;
	182	}
	183	if (swap_cnt == 0) { /* Switch to insertion sort */
f427ee49 A	184	for (pm = (char )a + es; pm < (char ) a + n * es; pm += es) {
	185	for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
	186	pl -= es) {
1c79356b	187	swap(pl, pl - es);
f427ee49 A	188	}
f427ee49 A	189	}
1c79356b A	190	return;
	191	}
	192
55e303ae	193	pn = (char )a + n es;
1c79356b A	194	r = min(pa - (char *)a, pb - pa);
1c79356b A	195	vecswap(a, pb - r, r);
f427ee49	196	r = min(pd - pc, pn - pd - es);
1c79356b	197	vecswap(pb, pn - r, r);
f427ee49	198	if ((size_t)(r = pb - pa) > es) {
1c79356b	199	qsort(a, r / es, es, cmp);
f427ee49 A	200	}
f427ee49 A	201	if ((size_t)(r = pd - pc) > es) {
1c79356b A	202	/* Iterate rather than recurse to save stack space */
	203	a = pn - r;
	204	n = r / es;
	205	goto loop;
	206	}
	207	/* qsort(pn - r, r / es, es, cmp);*/
	208	}
3e170ce0 A	209
3e170ce0 A	210	/* private KPI */
f427ee49 A	211	void
	212	kx_qsort(void array, size_t nm, size_t member_size, int (cmpf)(const void , const void ))
	213	{
	214	qsort(array, nm, member_size, cmpf);
3e170ce0	215	}