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-#ifndef __APPLE__
-/*-
- * Copyright (c) 1992, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Peter McIlroy.
- *
- * 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.
- */
-
-#if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)merge.c 8.2 (Berkeley) 2/14/94";
-#endif /* LIBC_SCCS and not lint */
-
-/*
- * Hybrid exponential search/linear search merge sort with hybrid
- * natural/pairwise first pass. Requires about .3% more comparisons
- * for random data than LSMS with pairwise first pass alone.
- * It works for objects as small as two bytes.
- */
-
-#define NATURAL
-#define THRESHOLD 16 /* Best choice for natural merge cut-off. */
-
-/* #define NATURAL to get hybrid natural merge.
- * (The default is pairwise merging.)
- */
-
-#include "system.h"
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include "lib/rpmdb_internal.h" /* XXX for mergesort */
-
-#define ISIZE sizeof(int)
-#define PSIZE sizeof(unsigned char *)
-#define ICOPY_LIST(src, dst, last) \
- do \
- *(int*)dst = *(int*)src, src += ISIZE, dst += ISIZE; \
- while(src < last)
-#define ICOPY_ELT(src, dst, i) \
- do \
- *(int*) dst = *(int*) src, src += ISIZE, dst += ISIZE; \
- while (i -= ISIZE)
-
-#define CCOPY_LIST(src, dst, last) \
- do \
- *dst++ = *src++; \
- while (src < last)
-#define CCOPY_ELT(src, dst, i) \
- do \
- *dst++ = *src++; \
- while (i -= 1)
-
-/*
- * Find the next possible pointer head. (Trickery for forcing an array
- * to do double duty as a linked list when objects do not align with word
- * boundaries.
- */
-/* Assumption: PSIZE is a power of 2. */
-#define EVAL(p) (unsigned char **) \
- ((unsigned char *)0 + \
- (((unsigned char *)p + PSIZE - 1 - (unsigned char *) 0) & ~(PSIZE - 1)))
-
-#define swap(a, b) { \
- s = b; \
- i = size; \
- do { \
- tmp = *a; *a++ = *s; *s++ = tmp; \
- } while (--i); \
- a -= size; \
- }
-#define reverse(bot, top) { \
- s = top; \
- do { \
- i = size; \
- do { \
- tmp = *bot; *bot++ = *s; *s++ = tmp; \
- } while (--i); \
- s -= size2; \
- } while(bot < s); \
-}
-
-/*
- * This is to avoid out-of-bounds addresses in sorting the
- * last 4 elements.
- */
-static void
-insertionsort(unsigned char *a, size_t n, size_t size,
- int (*cmp) (const void *, const void *))
-{
- unsigned char *ai, *s, *t, *u, tmp;
- int i;
-
- for (ai = a+size; --n >= 1; ai += size)
- for (t = ai; t > a; t -= size) {
- u = t - size;
- if (cmp(u, t) <= 0)
- break;
- swap(u, t);
- }
-}
-
-/*
- * Optional hybrid natural/pairwise first pass. Eats up list1 in runs of
- * increasing order, list2 in a corresponding linked list. Checks for runs
- * when THRESHOLD/2 pairs compare with same sense. (Only used when NATURAL
- * is defined. Otherwise simple pairwise merging is used.)
- */
-static void
-setup(unsigned char *list1, unsigned char *list2,
- size_t n, size_t size, int (*cmp) (const void *, const void *))
-{
- int i, length, size2, tmp, sense;
- unsigned char *f1, *f2, *s, *l2, *last, *p2;
-
- size2 = size*2;
- if (n <= 5) {
- insertionsort(list1, n, size, cmp);
- *EVAL(list2) = (unsigned char*) list2 + n*size;
- return;
- }
- /*
- * Avoid running pointers out of bounds; limit n to evens
- * for simplicity.
- */
- i = 4 + (n & 1);
- insertionsort(list1 + (n - i) * size, i, size, cmp);
- last = list1 + size * (n - i);
- *EVAL(list2 + (last - list1)) = list2 + n * size;
-
-#ifdef NATURAL
- p2 = list2;
- f1 = list1;
- sense = (cmp(f1, f1 + size) > 0);
- for (; f1 < last; sense = !sense) {
- length = 2;
- /* Find pairs with same sense. */
- for (f2 = f1 + size2; f2 < last; f2 += size2) {
- if ((cmp(f2, f2+ size) > 0) != sense)
- break;
- length += 2;
- }
- if (length < THRESHOLD) { /* Pairwise merge */
- do {
- p2 = *EVAL(p2) = f1 + size2 - list1 + list2;
- if (sense > 0)
- swap (f1, f1 + size);
- } while ((f1 += size2) < f2);
- } else { /* Natural merge */
- l2 = f2;
- for (f2 = f1 + size2; f2 < l2; f2 += size2) {
- if ((cmp(f2-size, f2) > 0) != sense) {
- p2 = *EVAL(p2) = f2 - list1 + list2;
- if (sense > 0)
- reverse(f1, f2-size);
- f1 = f2;
- }
- }
- if (sense > 0)
- reverse (f1, f2-size);
- f1 = f2;
- if (f2 < last || cmp(f2 - size, f2) > 0)
- p2 = *EVAL(p2) = f2 - list1 + list2;
- else
- p2 = *EVAL(p2) = list2 + n*size;
- }
- }
-#else /* pairwise merge only. */
- for (f1 = list1, p2 = list2; f1 < last; f1 += size2) {
- p2 = *EVAL(p2) = p2 + size2;
- if (cmp (f1, f1 + size) > 0)
- swap(f1, f1 + size);
- }
-#endif /* NATURAL */
-}
-
-/*
- * Arguments are as for qsort.
- */
-int
-mergesort(void *base, size_t nmemb, size_t size,
- int (*cmp) (const void *, const void *))
-{
- register int i, sense;
- int big, iflag;
- register unsigned char *f1, *f2, *t, *b, *q, *l1, *l2;
- register unsigned char *tp2;
- unsigned char *list2;
- unsigned char *list1;
- unsigned char *p2, *p, *last, **p1;
-
- if (size < PSIZE / 2) { /* Pointers must fit into 2 * size. */
- errno = EINVAL;
- return (-1);
- }
-
- if (nmemb == 0)
- return (0);
-
- /*
- * XXX
- * Stupid subtraction for the Cray.
- */
- iflag = 0;
- if (!(size % ISIZE) && !(((char *)base - (char *)0) % ISIZE))
- iflag = 1;
-
- if ((list2 = malloc(nmemb * size + PSIZE)) == NULL)
- return (-1);
-
- list1 = base;
- setup(list1, list2, nmemb, size, cmp);
- last = list2 + nmemb * size;
- i = big = 0;
- while (*EVAL(list2) != last) {
- l2 = list1;
- p1 = EVAL(list1);
- for (tp2 = p2 = list2; p2 != last; p1 = EVAL(l2)) {
- p2 = *EVAL(p2);
- f1 = l2;
- f2 = l1 = list1 + (p2 - list2);
- if (p2 != last)
- p2 = *EVAL(p2);
- l2 = list1 + (p2 - list2);
- while (f1 < l1 && f2 < l2) {
- if ((*cmp)(f1, f2) <= 0) {
- q = f2;
- b = f1, t = l1;
- sense = -1;
- } else {
- q = f1;
- b = f2, t = l2;
- sense = 0;
- }
- if (!big) { /* here i = 0 */
- while ((b += size) < t && cmp(q, b) >sense)
- if (++i == 6) {
- big = 1;
- goto EXPONENTIAL;
- }
- } else {
-EXPONENTIAL: for (i = size; ; i <<= 1)
- if ((p = (b + i)) >= t) {
- if ((p = t - size) > b &&
- (*cmp)(q, p) <= sense)
- t = p;
- else
- b = p;
- break;
- } else if ((*cmp)(q, p) <= sense) {
- t = p;
- if (i == size)
- big = 0;
- goto FASTCASE;
- } else
- b = p;
- while (t > b+size) {
- i = (((t - b) / size) >> 1) * size;
- if ((*cmp)(q, p = b + i) <= sense)
- t = p;
- else
- b = p;
- }
- goto COPY;
-FASTCASE: while (i > size)
- if ((*cmp)(q,
- p = b + (i >>= 1)) <= sense)
- t = p;
- else
- b = p;
-COPY: b = t;
- }
- i = size;
- if (q == f1) {
- if (iflag) {
- ICOPY_LIST(f2, tp2, b);
- ICOPY_ELT(f1, tp2, i);
- } else {
- CCOPY_LIST(f2, tp2, b);
- CCOPY_ELT(f1, tp2, i);
- }
- } else {
- if (iflag) {
- ICOPY_LIST(f1, tp2, b);
- ICOPY_ELT(f2, tp2, i);
- } else {
- CCOPY_LIST(f1, tp2, b);
- CCOPY_ELT(f2, tp2, i);
- }
- }
- }
- if (f2 < l2) {
- if (iflag)
- ICOPY_LIST(f2, tp2, l2);
- else
- CCOPY_LIST(f2, tp2, l2);
- } else if (f1 < l1) {
- if (iflag)
- ICOPY_LIST(f1, tp2, l1);
- else
- CCOPY_LIST(f1, tp2, l1);
- }
- *p1 = l2;
- }
- tp2 = list1; /* swap list1, list2 */
- list1 = list2;
- list2 = tp2;
- last = list2 + nmemb*size;
- }
- if (base == list2) {
- memmove(list2, list1, nmemb*size);
- list2 = list1;
- }
- free(list2);
- return (0);
-}
-#else
-/* mergesort is implemented in System on Mac OS X */
-#endif /* __APPLE__ */
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