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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libc/stdlib/radixsort.c	Lines:	0	96	0.0 %
Date:	2017-11-07	Branches:	0	90	0.0 %


/*	$OpenBSD: radixsort.c,v 1.9 2007/09/02 15:19:17 deraadt Exp $ */
/*-
 * 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.
 * 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.
 */

/*
 * 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 <errno.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);
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);

#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 = calloc(n, sizeof(a))) == NULL)
			return (-1);
		r_sort_b(a, ta, n, 0, tr, endch);
		free(ta);
	}
	return (0);
}

#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. */
void
r_sort_a(const u_char **a, int n, int i, const u_char *tr, u_int endch)
{
	static int count[256], 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];

	/* 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;
			}
		}

		/*
		 * 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. */
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[256], nc, bmin;
	int c;
	const u_char **ak, **ai;
	stack s[512], *sp, *sp0, *sp1, temp;
	const u_char **top[256];
	int *cp, bigc;

	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;
	}
}

static __inline void
simplesort(const u_char **a, int n, int b, const u_char *tr, u_int endch)
    /* insertion sort */
{
	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);
		}
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: radixsort.c,v 1.9 2007/09/02 15:19:17 deraadt Exp $ */
2			/*-
3			* Copyright (c) 1990, 1993
4			* The Regents of the University of California. All rights reserved.
5			*
6			* This code is derived from software contributed to Berkeley by
7			* Peter McIlroy and by Dan Bernstein at New York University,
8			*
9			* Redistribution and use in source and binary forms, with or without
10			* modification, are permitted provided that the following conditions
11			* are met:
12			* 1. Redistributions of source code must retain the above copyright
13			* notice, this list of conditions and the following disclaimer.
14			* 2. Redistributions in binary form must reproduce the above copyright
15			* notice, this list of conditions and the following disclaimer in the
16			* documentation and/or other materials provided with the distribution.
17			* 3. Neither the name of the University nor the names of its contributors
18			* may be used to endorse or promote products derived from this software
19			* without specific prior written permission.
20			*
21			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31			* SUCH DAMAGE.
32			*/
33
34			/*
35			* Radixsort routines.
36			*
37			* Program r_sort_a() is unstable but uses O(logN) extra memory for a stack.
38			* Use radixsort(a, n, trace, endchar) for this case.
39			*
40			* For stable sorting (using N extra pointers) use sradixsort(), which calls
41			* r_sort_b().
42			*
43			* For a description of this code, see D. McIlroy, P. McIlroy, K. Bostic,
44			* "Engineering Radix Sort".
45			*/
46
47			#include <sys/types.h>
48			#include <stdlib.h>
49			#include <errno.h>
50
51			typedef struct {
52			const u_char **sa;
53			int sn, si;
54			} stack;
55
56			static __inline void simplesort
57			(const u_char *, int, int, const u_char , u_int);
58			static void r_sort_a(const u_char *, int, int, const u_char , u_int);
59			static void r_sort_b(const u_char **,
60			const u_char *, int, int, const u_char , u_int);
61
62			#define THRESHOLD 20 /* Divert to simplesort(). */
63			#define SIZE 512 /* Default stack size. */
64
65			#define SETUP { \
66			if (tab == NULL) { \
67			tr = tr0; \
68			for (c = 0; c < endch; c++) \
69			tr0[c] = c + 1; \
70			tr0[c] = 0; \
71			for (c++; c < 256; c++) \
72			tr0[c] = c; \
73			endch = 0; \
74			} else { \
75			endch = tab[endch]; \
76			tr = tab; \
77			if (endch != 0 && endch != 255) { \
78			errno = EINVAL; \
79			return (-1); \
80			} \
81			} \
82			}
83
84			int
85			radixsort(const u_char *a, int n, const u_char tab, u_int endch)
86			{
87			const u_char *tr;
88			int c;
89			u_char tr0[256];
90
91			SETUP;
92			r_sort_a(a, n, 0, tr, endch);
93			return (0);
94			}
95
96			int
97			sradixsort(const u_char *a, int n, const u_char tab, u_int endch)
98			{
99			const u_char tr, *ta;
100			int c;
101			u_char tr0[256];
102
103			SETUP;
104			if (n < THRESHOLD)
105			simplesort(a, n, 0, tr, endch);
106			else {
107			if ((ta = calloc(n, sizeof(a))) == NULL)
108			return (-1);
109			r_sort_b(a, ta, n, 0, tr, endch);
110			free(ta);
111			}
112			return (0);
113			}
114
115			#define empty(s) (s >= sp)
116			#define pop(a, n, i) a = (--sp)->sa, n = sp->sn, i = sp->si
117			#define push(a, n, i) sp->sa = a, sp->sn = n, (sp++)->si = i
118			#define swap(a, b, t) t = a, a = b, b = t
119
120			/* Unstable, in-place sort. */
121			void
122			r_sort_a(const u_char *a, int n, int i, const u_char tr, u_int endch)
123			{
124			static int count[256], nc, bmin;
125			int c;
126			const u_char *ak, r;
127			stack s[SIZE], sp, sp0, *sp1, temp;
128			int *cp, bigc;
129			const u_char *an, t, aj, top[256];
130
131			/* Set up stack. */
132			sp = s;
133			push(a, n, i);
134			while (!empty(s)) {
135			pop(a, n, i);
136			if (n < THRESHOLD) {
137			simplesort(a, n, i, tr, endch);
138			continue;
139			}
140			an = a + n;
141
142			/* Make character histogram. */
143			if (nc == 0) {
144			bmin = 255; /* First occupied bin, excluding eos. */
145			for (ak = a; ak < an;) {
146			c = tr[(*ak++)[i]];
147			if (++count[c] == 1 && c != endch) {
148			if (c < bmin)
149			bmin = c;
150			nc++;
151			}
152			}
153			if (sp + nc > s + SIZE) { /* Get more stack. */
154			r_sort_a(a, n, i, tr, endch);
155			continue;
156			}
157			}
158
159			/*
160			* Set top[]; push incompletely sorted bins onto stack.
161			* top[] = pointers to last out-of-place element in bins.
162			* count[] = counts of elements in bins.
163			* Before permuting: top[c-1] + count[c] = top[c];
164			* during deal: top[c] counts down to top[c-1].
165			*/
166			sp0 = sp1 = sp; /* Stack position of biggest bin. */
167			bigc = 2; /* Size of biggest bin. */
168			if (endch == 0) /* Special case: set top[eos]. */
169			top[0] = ak = a + count[0];
170			else {
171			ak = a;
172			top[255] = an;
173			}
174			for (cp = count + bmin; nc > 0; cp++) {
175			while (cp == 0) / Find next non-empty pile. */
176			cp++;
177			if (*cp > 1) {
178			if (*cp > bigc) {
179			bigc = *cp;
180			sp1 = sp;
181			}
182			push(ak, *cp, i+1);
183			}
184			top[cp-count] = ak += *cp;
185			nc--;
186			}
187			swap(sp0, sp1, temp); /* Play it safe -- biggest bin last. */
188
189			/*
190			* Permute misplacements home. Already home: everything
191			* before aj, and in bin[c], items from top[c] on.
192			* Inner loop:
193			* r = next element to put in place;
194			* ak = top[r[i]] = location to put the next element.
195			* aj = bottom of 1st disordered bin.
196			* Outer loop:
197			* Once the 1st disordered bin is done, ie. aj >= ak,
198			* aj<-aj + count[c] connects the bins in a linked list;
199			* reset count[c].
200			*/
201			for (aj = a; aj < an; *aj = r, aj += count[c], count[c] = 0)
202			for (r = *aj; aj < (ak = --top[c = tr[r[i]]]);)
203			swap(*ak, r, t);
204			}
205			}
206
207			/* Stable sort, requiring additional memory. */
208			void
209			r_sort_b(const u_char a, const u_char ta, int n, int i, const u_char *tr,
210			u_int endch)
211			{
212			static int count[256], nc, bmin;
213			int c;
214			const u_char ak, ai;
215			stack s[512], sp, sp0, *sp1, temp;
216			const u_char **top[256];
217			int *cp, bigc;
218
219			sp = s;
220			push(a, n, i);
221			while (!empty(s)) {
222			pop(a, n, i);
223			if (n < THRESHOLD) {
224			simplesort(a, n, i, tr, endch);
225			continue;
226			}
227
228			if (nc == 0) {
229			bmin = 255;
230			for (ak = a + n; --ak >= a;) {
231			c = tr[(*ak)[i]];
232			if (++count[c] == 1 && c != endch) {
233			if (c < bmin)
234			bmin = c;
235			nc++;
236			}
237			}
238			if (sp + nc > s + SIZE) {
239			r_sort_b(a, ta, n, i, tr, endch);
240			continue;
241			}
242			}
243
244			sp0 = sp1 = sp;
245			bigc = 2;
246			if (endch == 0) {
247			top[0] = ak = a + count[0];
248			count[0] = 0;
249			} else {
250			ak = a;
251			top[255] = a + n;
252			count[255] = 0;
253			}
254			for (cp = count + bmin; nc > 0; cp++) {
255			while (*cp == 0)
256			cp++;
257			if ((c = *cp) > 1) {
258			if (c > bigc) {
259			bigc = c;
260			sp1 = sp;
261			}
262			push(ak, c, i+1);
263			}
264			top[cp-count] = ak += c;
265			cp = 0; / Reset count[]. */
266			nc--;
267			}
268			swap(sp0, sp1, temp);
269
270			for (ak = ta + n, ai = a+n; ak > ta;) /* Copy to temp. */
271			--ak = --ai;
272			for (ak = ta+n; --ak >= ta;) /* Deal to piles. */
273			--top[tr[(ak)[i]]] = *ak;
274			}
275			}
276
277			static __inline void
278			simplesort(const u_char *a, int n, int b, const u_char tr, u_int endch)
279			/* insertion sort */
280			{
281			u_char ch;
282			const u_char ak, ai, s, t;
283
284			for (ak = a+1; --n >= 1; ak++)
285			for (ai = ak; ai > a; ai--) {
286			for (s = ai[0] + b, t = ai[-1] + b;
287			(ch = tr[*s]) != endch; s++, t++)
288			if (ch != tr[*t])
289			break;
290			if (ch >= tr[*t])
291			break;
292			swap(ai[0], ai[-1], s);
293			}
294			}