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--- Libc/Libc-1725.40.4/stdlib/FreeBSD/radixsort.c
+++ /dev/null
@@ -1,336 +0,0 @@
-/*-
- * Copyright (c) 1990, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Peter McIlroy and by Dan Bernstein at New York University,
- *
- * 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.
- * 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[] = "@(#)radixsort.c 8.2 (Berkeley) 4/28/95";
-#endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/stdlib/radixsort.c,v 1.8 2007/01/09 00:28:10 imp Exp $");
-
-/*
- * Radixsort routines.
- *
- * Program r_sort_a() is unstable but uses O(logN) extra memory for a stack.
- * Use radixsort(a, n, trace, endchar) for this case.
- *
- * For stable sorting (using N extra pointers) use sradixsort(), which calls
- * r_sort_b().
- *
- * For a description of this code, see D. McIlroy, P. McIlroy, K. Bostic,
- * "Engineering Radix Sort".
- */
-
-#include <sys/types.h>
-#include <stdlib.h>
-#include <stddef.h>
-#include <errno.h>
-#include <pthread.h>
-
-typedef struct {
- const u_char **sa;
- int sn, si;
-} stack;
-
-static inline void simplesort
-(const u_char **, int, int, const u_char *, u_int) __attribute__((always_inline));
-static void r_sort_a(const u_char **, int, int, const u_char *, u_int);
-static void r_sort_b(const u_char **, const u_char **, int, int,
- const u_char *, u_int);
-
-static int *r_sort_a_count;
-static int *r_sort_b_count;
-
-static void r_sort_count_allocate(void);
-static pthread_once_t r_sort_count_control = PTHREAD_ONCE_INIT;
-
-#define THRESHOLD 20 /* Divert to simplesort(). */
-#define SIZE 512 /* Default stack size. */
-
-#define SETUP { \
- if (tab == NULL) { \
- tr = tr0; \
- for (c = 0; c < endch; c++) \
- tr0[c] = c + 1; \
- tr0[c] = 0; \
- for (c++; c < 256; c++) \
- tr0[c] = c; \
- endch = 0; \
- } else { \
- endch = tab[endch]; \
- tr = tab; \
- if (endch != 0 && endch != 255) { \
- errno = EINVAL; \
- return (-1); \
- } \
- } \
-}
-
-int
-radixsort(const u_char **a, int n, const u_char *tab, u_int endch)
-{
- const u_char *tr;
- int c;
- u_char tr0[256];
-
- SETUP;
- r_sort_a(a, n, 0, tr, endch);
- return (0);
-}
-
-int
-sradixsort(const u_char **a, int n, const u_char *tab, u_int endch)
-{
- const u_char *tr, **ta;
- int c;
- u_char tr0[256];
-
- SETUP;
- if (n < THRESHOLD)
- simplesort(a, n, 0, tr, endch);
- else {
- if ((ta = malloc(n * sizeof(a))) == NULL)
- return (-1);
- r_sort_b(a, ta, n, 0, tr, endch);
- free(ta);
- }
- return (0);
-}
-
-static void r_sort_count_allocate(void)
-{
- r_sort_a_count = calloc(256, sizeof(int));
- r_sort_b_count = calloc(256, sizeof(int));
-}
-
-#define empty(s) (s >= sp)
-#define pop(a, n, i) a = (--sp)->sa, n = sp->sn, i = sp->si
-#define push(a, n, i) sp->sa = a, sp->sn = n, (sp++)->si = i
-#define swap(a, b, t) t = a, a = b, b = t
-
-/* Unstable, in-place sort. */
-static void
-r_sort_a(const u_char **a, int n, int i, const u_char *tr, u_int endch)
-{
- static int *count, nc, bmin;
- int c;
- const u_char **ak, *r;
- stack s[SIZE], *sp, *sp0, *sp1, temp;
- int *cp, bigc;
- const u_char **an, *t, **aj, **top[256];
-
- if (pthread_once(&r_sort_count_control, r_sort_count_allocate)) {
- return;
- }
-
- count = r_sort_a_count;
-
- /* Set up stack. */
- sp = s;
- push(a, n, i);
- while (!empty(s)) {
- pop(a, n, i);
- if (n < THRESHOLD) {
- simplesort(a, n, i, tr, endch);
- continue;
- }
- an = a + n;
-
- /* Make character histogram. */
- if (nc == 0) {
- bmin = 255; /* First occupied bin, excluding eos. */
- for (ak = a; ak < an;) {
- c = tr[(*ak++)[i]];
- if (++count[c] == 1 && c != endch) {
- if (c < bmin)
- bmin = c;
- nc++;
- }
- }
- if (sp + nc > s + SIZE) { /* Get more stack. */
- r_sort_a(a, n, i, tr, endch);
- continue;
- }
- }
-
- /*
- * Special case: if all strings have the same
- * character at position i, move on to the next
- * character.
- */
- if (nc == 1 && count[bmin] == n) {
- push(a, n, i+1);
- nc = count[bmin] = 0;
- continue;
- }
-
- /*
- * Set top[]; push incompletely sorted bins onto stack.
- * top[] = pointers to last out-of-place element in bins.
- * count[] = counts of elements in bins.
- * Before permuting: top[c-1] + count[c] = top[c];
- * during deal: top[c] counts down to top[c-1].
- */
- sp0 = sp1 = sp; /* Stack position of biggest bin. */
- bigc = 2; /* Size of biggest bin. */
- if (endch == 0) /* Special case: set top[eos]. */
- top[0] = ak = a + count[0];
- else {
- ak = a;
- top[255] = an;
- }
- for (cp = count + bmin; nc > 0; cp++) {
- while (*cp == 0) /* Find next non-empty pile. */
- cp++;
- if (*cp > 1) {
- if (*cp > bigc) {
- bigc = *cp;
- sp1 = sp;
- }
- push(ak, *cp, i+1);
- }
- top[cp-count] = ak += *cp;
- nc--;
- }
- swap(*sp0, *sp1, temp); /* Play it safe -- biggest bin last. */
-
- /*
- * Permute misplacements home. Already home: everything
- * before aj, and in bin[c], items from top[c] on.
- * Inner loop:
- * r = next element to put in place;
- * ak = top[r[i]] = location to put the next element.
- * aj = bottom of 1st disordered bin.
- * Outer loop:
- * Once the 1st disordered bin is done, ie. aj >= ak,
- * aj<-aj + count[c] connects the bins in a linked list;
- * reset count[c].
- */
- for (aj = a; aj < an; *aj = r, aj += count[c], count[c] = 0)
- for (r = *aj; aj < (ak = --top[c = tr[r[i]]]);)
- swap(*ak, r, t);
- }
-}
-
-/* Stable sort, requiring additional memory. */
-static void
-r_sort_b(const u_char **a, const u_char **ta, int n, int i, const u_char *tr,
- u_int endch)
-{
- static int *count, nc, bmin;
- int c;
- const u_char **ak, **ai;
- stack s[512], *sp, *sp0, *sp1, temp;
- const u_char **top[256];
- int *cp, bigc;
-
- if (pthread_once(&r_sort_count_control, r_sort_count_allocate)) {
- return;
- }
-
- count = r_sort_b_count;
-
- sp = s;
- push(a, n, i);
- while (!empty(s)) {
- pop(a, n, i);
- if (n < THRESHOLD) {
- simplesort(a, n, i, tr, endch);
- continue;
- }
-
- if (nc == 0) {
- bmin = 255;
- for (ak = a + n; --ak >= a;) {
- c = tr[(*ak)[i]];
- if (++count[c] == 1 && c != endch) {
- if (c < bmin)
- bmin = c;
- nc++;
- }
- }
- if (sp + nc > s + SIZE) {
- r_sort_b(a, ta, n, i, tr, endch);
- continue;
- }
- }
-
- sp0 = sp1 = sp;
- bigc = 2;
- if (endch == 0) {
- top[0] = ak = a + count[0];
- count[0] = 0;
- } else {
- ak = a;
- top[255] = a + n;
- count[255] = 0;
- }
- for (cp = count + bmin; nc > 0; cp++) {
- while (*cp == 0)
- cp++;
- if ((c = *cp) > 1) {
- if (c > bigc) {
- bigc = c;
- sp1 = sp;
- }
- push(ak, c, i+1);
- }
- top[cp-count] = ak += c;
- *cp = 0; /* Reset count[]. */
- nc--;
- }
- swap(*sp0, *sp1, temp);
-
- for (ak = ta + n, ai = a+n; ak > ta;) /* Copy to temp. */
- *--ak = *--ai;
- for (ak = ta+n; --ak >= ta;) /* Deal to piles. */
- *--top[tr[(*ak)[i]]] = *ak;
- }
-}
-
-/* insertion sort */
-static inline void
-simplesort(const u_char **a, int n, int b, const u_char *tr, u_int endch)
-{
- u_char ch;
- const u_char **ak, **ai, *s, *t;
-
- for (ak = a+1; --n >= 1; ak++)
- for (ai = ak; ai > a; ai--) {
- for (s = ai[0] + b, t = ai[-1] + b;
- (ch = tr[*s]) != endch; s++, t++)
- if (ch != tr[*t])
- break;
- if (ch >= tr[*t])
- break;
- swap(ai[0], ai[-1], s);
- }
-}