--- /dev/null
+/* The following is the NetBSD libc qsort implementation modified in order to
+ * support partial sorting of ranges for Redis.
+ *
+ * Copyright(C) 2009 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 <sys/cdefs.h>
+#if defined(LIBC_SCCS) && !defined(lint)
+#if 0
+static char sccsid[] = "@(#)qsort.c 8.1 (Berkeley) 6/4/93";
+#else
+__RCSID("$NetBSD: qsort.c,v 1.19 2009/01/30 23:38:44 lukem Exp $");
+#endif
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <stdlib.h>
+
+static inline char *med3 __P((char *, char *, char *,
+ int (*)(const void *, const void *)));
+static inline void swapfunc __P((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 = ((char *)a - (char *)0) % 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) __P((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) __P((const void *, const void *)), void *lrange, void *rrange)
+{
+ char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+ size_t d, r;
+ int swaptype, swap_cnt, cmp_result;
+
+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, 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_cnt = 1;
+ swap(pa, pb);
+ pa += es;
+ }
+ pb += es;
+ }
+ while (pb <= pc && (cmp_result = cmp(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;
+ }
+ 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((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) __P((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);
+}
projects / redis.git / commitdiff
