+++ /dev/null
-/*
- * Copyright (c) 2005 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_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. 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_LICENSE_HEADER_END@
- */
-/* CFSortFunctions.c
- Copyright 1999-2002, Apple, Inc. All rights reserved.
- Responsibility: Christopher Kane
-*/
-
-/* This file contains code copied from the Libc project's files
- qsort.c, merge.c, and heapsort.c, and modified to suit the
- needs of CF, which needs the comparison callback to have an
- additional parameter. The code is collected into this one
- file so that the individual BSD sort routines can remain
- private and static. We may not keep the bsd functions
- separate eventually.
-*/
-
-#include <CoreFoundation/CFBase.h>
-#if defined(__MACH__) || defined(__LINUX__) || defined(__FREEBSD__)
-#include <sys/types.h>
-#else
-#define EINVAL 22
-#endif
-#include <stdlib.h>
-#include <errno.h>
-#include <string.h>
-#include <stddef.h>
-#include "CFInternal.h"
-
-static int bsd_mergesort(void *base, int nmemb, int size, CFComparatorFunction cmp, void *context);
-
-/* Comparator is passed the address of the values. */
-void CFMergeSortArray(void *list, CFIndex count, CFIndex elementSize, CFComparatorFunction comparator, void *context) {
- bsd_mergesort(list, count, elementSize, comparator, context);
-}
-
-#if 0
-// non-recursing qsort with side index list which is the actual thing sorted
-// XXX kept here for possible later reference
-void cjk_big_isort(char *list, int size, int *idx_list, int (*comp)(const void *, const void *, void *), void *context, int lo, int hi) {
- int t, idx, idx2;
- char *v1;
- for (idx = lo + 1; idx < hi + 1; idx++) {
- t = idx_list[idx];
- v1 = list + t * size;
- for (idx2 = idx; lo < idx2 && (comp(v1, list + idx_list[idx2 - 1] * size, context) < 0); idx2--)
- idx_list[idx2] = idx_list[idx2 - 1];
- idx_list[idx2] = t;
- }
-}
-
-void cjk_big_qsort(char *list, int size, int *idx_list, int (*comp)(const void *, const void *, void *), void *context, int lo, int hi, int *recurse) {
- int p, idx, mid, g1, g2, g3, r1, r2;
- char *v1, *v2, *v3;
- g1 = lo;
- g2 = (hi + lo) / 2; //random() % (hi - lo + 1) + lo;
- g3 = hi;
- v1 = list + idx_list[g1] * size;
- v2 = list + idx_list[g2] * size;
- v3 = list + idx_list[g3] * size;
- if (comp(v1, v2, context) < 0) {
- p = comp(v2, v3, context) < 0 ? g2 : (comp(v1, v3, context) < 0 ? g3 : g1);
- } else {
- p = comp(v2, v3, context) > 0 ? g2 : (comp(v1, v3, context) < 0 ? g1 : g3);
- }
- if (lo != p) {int t = idx_list[lo]; idx_list[lo] = idx_list[p]; idx_list[p] = t;}
- r2 = 1;
- v2 = list + idx_list[lo] * size;
- for (mid = lo, idx = lo + 1; idx < hi + 1; idx++) {
- v1 = list + idx_list[idx] * size;
- r1 = comp(v1, v2, context);
- r2 = r2 && (0 == r1);
- if (r1 < 0) {
- mid++;
- if (idx != mid) {int t = idx_list[idx]; idx_list[idx] = idx_list[mid]; idx_list[mid] = t;}
- }
- }
- if (lo != mid) {int t = idx_list[lo]; idx_list[lo] = idx_list[mid]; idx_list[mid] = t;}
- *recurse = !r2 ? mid : -1;
-}
-
-void cjk_big_sort(char *list, int n, int size, int (*comp)(const void *, const void *, void *), void *context) {
- int len = 0, los[40], his[40];
- // 40 is big enough for 2^40 elements, in theory; in practice, much
- // lower but still sufficient; should recurse if the 40 limit is hit
- int *idx_list = malloc(sizeof(int) * n);
- char *tmp_list = malloc(n * size);
- int idx;
- for (idx = 0; idx < n; idx++) {
- idx_list[idx] = idx;
- }
- los[len] = 0;
- his[len++] = n - 1;
- while (0 < len) {
- int lo, hi;
- len--;
- lo = los[len];
- hi = his[len];
- if (5 < (hi - lo)) {
- int mid;
- cjk_big_qsort(list, size, idx_list, comp, context, lo, hi, &mid);
- if (0 < mid) {
- los[len] = lo;
- his[len++] = mid - 1;
- los[len] = mid + 1;
- his[len++] = hi;
- }
- } else {
- cjk_big_isort(list, size, idx_list, comp, context, lo, hi);
- }
- }
- for (idx = 0; idx < n; idx++)
- memmove(tmp_list + idx * size, list + idx_list[idx] * size, size);
- memmove(list, tmp_list, n * size);
- free(tmp_list);
- free(idx_list);
-}
-#endif
-
-
-/* stdlib.subproj/qsort.c ============================================== */
-
-/*
- * 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.
- */
-
-#if !defined(min)
-#define min(a, b) (a) < (b) ? a : b
-#endif
-
-/*
- * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
- */
-#define swapcode(TYPE, parmi, parmj, n) { \
- long i = (n) / sizeof (TYPE); \
- register TYPE *pi = (TYPE *) (parmi); \
- register TYPE *pj = (TYPE *) (parmj); \
- do { \
- register 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;
-
-CF_INLINE void
-swapfunc(char *a, char *b, int 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)
-
-CF_INLINE char *
-med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *, void *), void *context) {
- return cmp(a, b, context) < 0 ?
- (cmp(b, c, context) < 0 ? b : (cmp(a, c, context) < 0 ? c : a ))
- :(cmp(b, c, context) > 0 ? b : (cmp(a, c, context) < 0 ? a : c ));
-}
-
-/* Comparator is passed the address of the values. */
-void CFQSortArray(void *aVoidStar, CFIndex n, CFIndex es, CFComparatorFunction cmp, void *context)
-{
- char *a = (char *)aVoidStar;
- char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
- int d, r, swaptype, swap_cnt;
-
-loop: SWAPINIT(a, es);
- swap_cnt = 0;
- if (n < 7) {
- for (pm = a + es; pm < (char *) a + n * es; pm += es)
- for (pl = pm; pl > (char *) a && cmp(pl - es, pl, context) > 0;
- pl -= es)
- swap(pl, pl - es);
- return;
- }
- pm = a + (n / 2) * es;
- if (n > 7) {
- pl = a;
- pn = a + (n - 1) * es;
- if (n > 40) {
- d = (n / 8) * es;
- pl = med3(pl, pl + d, pl + 2 * d, cmp, context);
- pm = med3(pm - d, pm, pm + d, cmp, context);
- pn = med3(pn - 2 * d, pn - d, pn, cmp, context);
- }
- pm = med3(pl, pm, pn, cmp, context);
- }
- swap(a, pm);
- pa = pb = a + es;
-
- pc = pd = a + (n - 1) * es;
- for (;;) {
- while (pb <= pc && (r = cmp(pb, a, context)) <= 0) {
- if (r == 0) {
- swap_cnt = 1;
- swap(pa, pb);
- pa += es;
- }
- pb += es;
- }
- while (pb <= pc && (r = cmp(pc, a, context)) >= 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 = a + es; pm < (char *) a + n * es; pm += es)
- for (pl = pm; pl > (char *) a && cmp(pl - es, pl, context) > 0;
- pl -= es)
- swap(pl, pl - es);
- return;
- }
-
- pn = 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 ((r = pb - pa) > es)
- CFQSortArray(a, r / es, es, cmp, context);
- if ((r = pd - pc) > es) {
- /* Iterate rather than recurse to save stack space */
- a = pn - r;
- n = r / es;
- goto loop;
- }
-/* CFQSortArray(pn - r, r / es, es, cmp, context);*/
-}
-
-#undef min
-#undef swapcode
-#undef SWAPINIT
-#undef swap
-#undef vecswap
-
-/* stdlib.subproj/mergesort.c ========================================== */
-
-/*
- * 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.
- */
-
-
-/*
- * 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.)
- */
-
-
-#define ISIZE sizeof(int)
-#define PSIZE sizeof(uint8_t *)
-#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) (uint8_t **) \
- ((uint8_t *)0 + \
- (((uint8_t *)p + PSIZE - 1 - (uint8_t *) 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(char *a, int n, int size, int (*cmp)(const void *, const void *, void *), void *context) {
- 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, context) <= 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(char *list1, char *list2, int n, int size, int (*cmp)(const void *, const void *, void *), void *context) {
- int i, length, size2, tmp, sense;
- char *f1, *f2, *s, *l2, *last, *p2;
-
- size2 = size*2;
- if (n <= 5) {
- insertionsort(list1, n, size, cmp, context);
- *EVAL(list2) = (uint8_t*) 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, context);
- last = list1 + size * (n - i);
- *EVAL(list2 + (last - list1)) = list2 + n * size;
-
-#ifdef NATURAL
- p2 = list2;
- f1 = list1;
- sense = (cmp(f1, f1 + size, context) > 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, context) > 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, context) > 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, context) > 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, context) > 0)
- swap(f1, f1 + size);
- }
-#endif /* NATURAL */
-}
-
-/*
- * Arguments are as for qsort.
- */
-static int
-bsd_mergesort(void *base, int nmemb, int size, CFComparatorFunction cmp, void *context) {
- register int i, sense;
- int big, iflag;
- register uint8_t *f1, *f2, *t, *b, *tp2, *q, *l1, *l2;
- uint8_t *list2, *list1, *p2, *p, *last, **p1;
-
- if (size < (int)PSIZE / 2) { /* Pointers must fit into 2 * size. */
- errno = EINVAL;
- return (-1);
- }
-
- /*
- * 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, context);
- 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, context) <= 0) {
- q = f2;
- b = f1, t = l1;
- sense = -1;
- } else {
- q = f1;
- b = f2, t = l2;
- sense = 0;
- }
- if (!big) { /* here i = 0 */
-/* LINEAR: */ while ((b += size) < t && cmp(q, b, context) >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, context) <= sense)
- t = p;
- else
- b = p;
- break;
- } else if ((*cmp)(q, p, context) <= sense) {
- t = p;
- if (i == size)
- big = 0;
- goto FASTCASE;
- } else
- b = p;
-/* SLOWCASE: */ while (t > b+size) {
- i = (((t - b) / size) >> 1) * size;
- if ((*cmp)(q, p = b + i, context) <= sense)
- t = p;
- else
- b = p;
- }
- goto COPY;
-FASTCASE: while (i > size)
- if ((*cmp)(q,
- p = b + (i >>= 1), context) <= 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);
-}
-
-#undef NATURAL
-#undef THRESHOLD
-#undef ISIZE
-#undef PSIZE
-#undef ICOPY_LIST
-#undef ICOPY_ELT
-#undef CCOPY_LIST
-#undef CCOPY_ELT
-#undef EVAL
-#undef swap
-#undef reverse
-
-#if 0
-/* stdlib.subproj/heapsort.c =========================================== */
-
-/*
- * Copyright (c) 1991, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Ronnie Kon at Mindcraft Inc., Kevin Lew and Elmer Yglesias.
- *
- * 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.
- */
-
-/*
- * Swap two areas of size number of bytes. Although qsort(3) permits random
- * blocks of memory to be sorted, sorting pointers is almost certainly the
- * common case (and, were it not, could easily be made so). Regardless, it
- * isn't worth optimizing; the SWAP's get sped up by the cache, and pointer
- * arithmetic gets lost in the time required for comparison function calls.
- */
-#define SWAP(a, b, count, size, tmp) { \
- count = size; \
- do { \
- tmp = *a; \
- *a++ = *b; \
- *b++ = tmp; \
- } while (--count); \
-}
-
-/* Copy one block of size size to another. */
-#define COPY(a, b, count, size, tmp1, tmp2) { \
- count = size; \
- tmp1 = a; \
- tmp2 = b; \
- do { \
- *tmp1++ = *tmp2++; \
- } while (--count); \
-}
-
-/*
- * Build the list into a heap, where a heap is defined such that for
- * the records K1 ... KN, Kj/2 >= Kj for 1 <= j/2 <= j <= N.
- *
- * There two cases. If j == nmemb, select largest of Ki and Kj. If
- * j < nmemb, select largest of Ki, Kj and Kj+1.
- */
-#define CREATE(initval, nmemb, par_i, child_i, par, child, size, count, tmp) { \
- for (par_i = initval; (child_i = par_i * 2) <= nmemb; \
- par_i = child_i) { \
- child = base + child_i * size; \
- if (child_i < nmemb && compar(child, child + size, context) < 0) { \
- child += size; \
- ++child_i; \
- } \
- par = base + par_i * size; \
- if (compar(child, par, context) <= 0) \
- break; \
- SWAP(par, child, count, size, tmp); \
- } \
-}
-
-/*
- * Select the top of the heap and 'heapify'. Since by far the most expensive
- * action is the call to the compar function, a considerable optimization
- * in the average case can be achieved due to the fact that k, the displaced
- * elememt, is ususally quite small, so it would be preferable to first
- * heapify, always maintaining the invariant that the larger child is copied
- * over its parent's record.
- *
- * Then, starting from the *bottom* of the heap, finding k's correct place,
- * again maintianing the invariant. As a result of the invariant no element
- * is 'lost' when k is assigned its correct place in the heap.
- *
- * The time savings from this optimization are on the order of 15-20% for the
- * average case. See Knuth, Vol. 3, page 158, problem 18.
- *
- * XXX Don't break the #define SELECT line, below. Reiser cpp gets upset.
- */
-#define SELECT(par_i, child_i, nmemb, par, child, size, k, count, tmp1, tmp2) { \
- for (par_i = 1; (child_i = par_i * 2) <= nmemb; par_i = child_i) { \
- child = base + child_i * size; \
- if (child_i < nmemb && compar(child, child + size, context) < 0) { \
- child += size; \
- ++child_i; \
- } \
- par = base + par_i * size; \
- COPY(par, child, count, size, tmp1, tmp2); \
- } \
- for (;;) { \
- child_i = par_i; \
- par_i = child_i / 2; \
- child = base + child_i * size; \
- par = base + par_i * size; \
- if (child_i == 1 || compar(k, par, context) < 0) { \
- COPY(child, k, count, size, tmp1, tmp2); \
- break; \
- } \
- COPY(child, par, count, size, tmp1, tmp2); \
- } \
-}
-
-/*
- * Heapsort -- Knuth, Vol. 3, page 145. Runs in O (N lg N), both average
- * and worst. While heapsort is faster than the worst case of quicksort,
- * the BSD quicksort does median selection so that the chance of finding
- * a data set that will trigger the worst case is nonexistent. Heapsort's
- * only advantage over quicksort is that it requires little additional memory.
- */
-static int
-bsd_heapsort(void *vbase, int nmemb, int size, int (*compar)(const void *, const void *, void *), void *context) {
- register int cnt, i, j, l;
- register char tmp, *tmp1, *tmp2;
- char *base, *k, *p, *t;
-
- if (nmemb <= 1)
- return (0);
-
- if (!size) {
- errno = EINVAL;
- return (-1);
- }
-
- if ((k = malloc(size)) == NULL)
- return (-1);
-
- /*
- * Items are numbered from 1 to nmemb, so offset from size bytes
- * below the starting address.
- */
- base = (char *)vbase - size;
-
- for (l = nmemb / 2 + 1; --l;)
- CREATE(l, nmemb, i, j, t, p, size, cnt, tmp);
-
- /*
- * For each element of the heap, save the largest element into its
- * final slot, save the displaced element (k), then recreate the
- * heap.
- */
- while (nmemb > 1) {
- COPY(k, base + nmemb * size, cnt, size, tmp1, tmp2);
- COPY(base + nmemb * size, base + size, cnt, size, tmp1, tmp2);
- --nmemb;
- SELECT(i, j, nmemb, t, p, size, k, cnt, tmp1, tmp2);
- }
- free(k);
- return (0);
-}
-
-#undef SWAP
-#undef COPY
-#undef CREATE
-#undef SELECT
-
-#endif
-
-/* ===================================================================== */
-
-#undef EINVAL
-
projects / apple / cf.git / blobdiff