11590Srgrimes/*- 21590Srgrimes * Copyright (c) 1992, 1993 31590Srgrimes * The Regents of the University of California. All rights reserved. 41590Srgrimes * 51590Srgrimes * Redistribution and use in source and binary forms, with or without 61590Srgrimes * modification, are permitted provided that the following conditions 71590Srgrimes * are met: 81590Srgrimes * 1. Redistributions of source code must retain the above copyright 91590Srgrimes * notice, this list of conditions and the following disclaimer. 101590Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111590Srgrimes * notice, this list of conditions and the following disclaimer in the 121590Srgrimes * documentation and/or other materials provided with the distribution. 131590Srgrimes * 4. Neither the name of the University nor the names of its contributors 141590Srgrimes * may be used to endorse or promote products derived from this software 151590Srgrimes * without specific prior written permission. 161590Srgrimes * 171590Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 181590Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 191590Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 201590Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 211590Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 221590Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 231590Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 241590Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 251590Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 261590Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 271590Srgrimes * SUCH DAMAGE. 281590Srgrimes */ 291590Srgrimes 3087701Smarkm#include <sys/cdefs.h> 3187701Smarkm__FBSDID("$FreeBSD$"); 3287701Smarkm 3387701Smarkm#include <sys/param.h> 341590Srgrimes#include <sys/libkern.h> 3587701Smarkm 3628370Scharnier#ifdef I_AM_QSORT_R 371590Srgrimestypedef int cmp_t(void *, const void *, const void *); 381590Srgrimes#else 3987701Smarkmtypedef int cmp_t(const void *, const void *); 4028370Scharnier#endif 4128370Scharnierstatic __inline char *med3(char *, char *, char *, cmp_t *, void *); 421590Srgrimesstatic __inline void swapfunc(char *, char *, int, int); 431590Srgrimes 4487701Smarkm#define min(a, b) (a) < (b) ? (a) : (b) 451590Srgrimes 461590Srgrimes/* 471590Srgrimes * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function". 481590Srgrimes */ 491590Srgrimes#define swapcode(TYPE, parmi, parmj, n) { \ 501590Srgrimes long i = (n) / sizeof (TYPE); \ 511590Srgrimes register TYPE *pi = (TYPE *) (parmi); \ 52200419Sdelphij register TYPE *pj = (TYPE *) (parmj); \ 531590Srgrimes do { \ 541590Srgrimes register TYPE t = *pi; \ 551590Srgrimes *pi++ = *pj; \ 561590Srgrimes *pj++ = t; \ 571590Srgrimes } while (--i > 0); \ 581590Srgrimes} 59229403Sed 6028370Scharnier#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \ 611590Srgrimes es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1; 621590Srgrimes 631590Srgrimesstatic __inline void 6487701Smarkmswapfunc(char *a, char *b, int n, int swaptype) 651590Srgrimes{ 661590Srgrimes if(swaptype <= 1) 671590Srgrimes swapcode(long, a, b, n) 6887701Smarkm else 691590Srgrimes swapcode(char, a, b, n) 701590Srgrimes} 711590Srgrimes 721590Srgrimes#define swap(a, b) \ 731590Srgrimes if (swaptype == 0) { \ 741590Srgrimes long t = *(long *)(a); \ 751590Srgrimes *(long *)(a) = *(long *)(b); \ 761590Srgrimes *(long *)(b) = t; \ 771590Srgrimes } else \ 781590Srgrimes swapfunc(a, b, es, swaptype) 791590Srgrimes 801590Srgrimes#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype) 811590Srgrimes 821590Srgrimes#ifdef I_AM_QSORT_R 831590Srgrimes#define CMP(t, x, y) (cmp((t), (x), (y))) 841590Srgrimes#else 851590Srgrimes#define CMP(t, x, y) (cmp((x), (y))) 861590Srgrimes#endif 871590Srgrimes 881590Srgrimesstatic __inline char * 891590Srgrimesmed3(char *a, char *b, char *c, cmp_t *cmp, void *thunk 901590Srgrimes#ifndef I_AM_QSORT_R 911590Srgrimes__unused 921590Srgrimes#endif 931590Srgrimes) 941590Srgrimes{ 951590Srgrimes return CMP(thunk, a, b) < 0 ? 961590Srgrimes (CMP(thunk, b, c) < 0 ? b : (CMP(thunk, a, c) < 0 ? c : a )) 971590Srgrimes :(CMP(thunk, b, c) > 0 ? b : (CMP(thunk, a, c) < 0 ? a : c )); 981590Srgrimes} 991590Srgrimes 1001590Srgrimes#ifdef I_AM_QSORT_R 1011590Srgrimesvoid 1021590Srgrimesqsort_r(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp) 1031590Srgrimes#else 1041590Srgrimes#define thunk NULL 1051590Srgrimesvoid 1061590Srgrimesqsort(void *a, size_t n, size_t es, cmp_t *cmp) 1071590Srgrimes#endif 1081590Srgrimes{ 1091590Srgrimes char *pa, *pb, *pc, *pd, *pl, *pm, *pn; 1101590Srgrimes int d, r, swaptype, swap_cnt; 1111590Srgrimes 1121590Srgrimesloop: SWAPINIT(a, es); 1131590Srgrimes swap_cnt = 0; 1141590Srgrimes if (n < 7) { 115 for (pm = (char *)a + es; pm < (char *)a + n * es; pm += es) 116 for (pl = pm; pl > (char *)a && CMP(thunk, pl - es, pl) > 0; 117 pl -= es) 118 swap(pl, pl - es); 119 return; 120 } 121 pm = (char *)a + (n / 2) * es; 122 if (n > 7) { 123 pl = a; 124 pn = (char *)a + (n - 1) * es; 125 if (n > 40) { 126 d = (n / 8) * es; 127 pl = med3(pl, pl + d, pl + 2 * d, cmp, thunk); 128 pm = med3(pm - d, pm, pm + d, cmp, thunk); 129 pn = med3(pn - 2 * d, pn - d, pn, cmp, thunk); 130 } 131 pm = med3(pl, pm, pn, cmp, thunk); 132 } 133 swap(a, pm); 134 pa = pb = (char *)a + es; 135 136 pc = pd = (char *)a + (n - 1) * es; 137 for (;;) { 138 while (pb <= pc && (r = CMP(thunk, pb, a)) <= 0) { 139 if (r == 0) { 140 swap_cnt = 1; 141 swap(pa, pb); 142 pa += es; 143 } 144 pb += es; 145 } 146 while (pb <= pc && (r = CMP(thunk, pc, a)) >= 0) { 147 if (r == 0) { 148 swap_cnt = 1; 149 swap(pc, pd); 150 pd -= es; 151 } 152 pc -= es; 153 } 154 if (pb > pc) 155 break; 156 swap(pb, pc); 157 swap_cnt = 1; 158 pb += es; 159 pc -= es; 160 } 161 if (swap_cnt == 0) { /* Switch to insertion sort */ 162 for (pm = (char *)a + es; pm < (char *)a + n * es; pm += es) 163 for (pl = pm; pl > (char *)a && CMP(thunk, pl - es, pl) > 0; 164 pl -= es) 165 swap(pl, pl - es); 166 return; 167 } 168 169 pn = (char *)a + n * es; 170 r = min(pa - (char *)a, pb - pa); 171 vecswap(a, pb - r, r); 172 r = min(pd - pc, pn - pd - es); 173 vecswap(pb, pn - r, r); 174 if ((r = pb - pa) > es) 175#ifdef I_AM_QSORT_R 176 qsort_r(a, r / es, es, thunk, cmp); 177#else 178 qsort(a, r / es, es, cmp); 179#endif 180 if ((r = pd - pc) > es) { 181 /* Iterate rather than recurse to save stack space */ 182 a = pn - r; 183 n = r / es; 184 goto loop; 185 } 186} 187