From 317c0644ccf108aa23ef3fd8358bd66c2840bfc0 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 14 Apr 2024 15:40:54 +0200 Subject: Adding upstream version 5:7.2.4. Signed-off-by: Daniel Baumann --- src/pqsort.c | 185 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 185 insertions(+) create mode 100644 src/pqsort.c (limited to 'src/pqsort.c') diff --git a/src/pqsort.c b/src/pqsort.c new file mode 100644 index 0000000..fab54e0 --- /dev/null +++ b/src/pqsort.c @@ -0,0 +1,185 @@ +/* The following is the NetBSD libc qsort implementation modified in order to + * support partial sorting of ranges for Redis. + * + * Copyright(C) 2009-2012 Salvatore Sanfilippo. All rights reserved. + * + * The original copyright notice follows. */ + + +/* $NetBSD: qsort.c,v 1.19 2009/01/30 23:38:44 lukem Exp $ */ + +/*- + * 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. + */ + +#include +#include +#include +#include + +static inline char *med3 (char *, char *, char *, + int (*)(const void *, const void *)); +static inline void swapfunc (char *, char *, size_t, 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 *)(void *)(parmi); \ + TYPE *pj = (TYPE *)(void *)(parmj); \ + do { \ + TYPE t = *pi; \ + *pi++ = *pj; \ + *pj++ = t; \ + } while (--i > 0); \ +} + +#define SWAPINIT(a, es) swaptype = (uintptr_t)a % sizeof(long) || \ + es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1; + +static inline void +swapfunc(char *a, char *b, size_t 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 *)(void *)(a); \ + *(long *)(void *)(a) = *(long *)(void *)(b); \ + *(long *)(void *)(b) = t; \ + } else \ + swapfunc(a, b, es, swaptype) + +#define vecswap(a, b, n) if ((n) > 0) swapfunc((a), (b), (size_t)(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 )); +} + +static void +_pqsort(void *a, size_t n, size_t es, + int (*cmp) (const void *, const void *), void *lrange, void *rrange) +{ + char *pa, *pb, *pc, *pd, *pl, *pm, *pn; + size_t d, r; + int swaptype, cmp_result; + +loop: SWAPINIT(a, es); + 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, pl - es); + return; + } + pm = (char *) a + (n / 2) * es; + if (n > 7) { + pl = (char *) 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 && (cmp_result = cmp(pb, a)) <= 0) { + if (cmp_result == 0) { + swap(pa, pb); + pa += es; + } + pb += es; + } + while (pb <= pc && (cmp_result = cmp(pc, a)) >= 0) { + if (cmp_result == 0) { + swap(pc, pd); + pd -= es; + } + pc -= es; + } + if (pb > pc) + break; + swap(pb, pc); + pb += es; + pc -= es; + } + + pn = (char *) a + n * es; + r = min(pa - (char *) a, pb - pa); + vecswap(a, pb - r, r); + r = min((size_t)(pd - pc), pn - pd - es); + vecswap(pb, pn - r, r); + if ((r = pb - pa) > es) { + void *_l = a, *_r = ((unsigned char*)a)+r-1; + if (!((lrange < _l && rrange < _l) || + (lrange > _r && rrange > _r))) + _pqsort(a, r / es, es, cmp, lrange, rrange); + } + if ((r = pd - pc) > es) { + void *_l, *_r; + + /* Iterate rather than recurse to save stack space */ + a = pn - r; + n = r / es; + + _l = a; + _r = ((unsigned char*)a)+r-1; + if (!((lrange < _l && rrange < _l) || + (lrange > _r && rrange > _r))) + goto loop; + } +/* qsort(pn - r, r / es, es, cmp);*/ +} + +void +pqsort(void *a, size_t n, size_t es, + int (*cmp) (const void *, const void *), size_t lrange, size_t rrange) +{ + _pqsort(a,n,es,cmp,((unsigned char*)a)+(lrange*es), + ((unsigned char*)a)+((rrange+1)*es)-1); +} -- cgit v1.2.3