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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libc/stdlib/hcreate.c	Lines:	0	46	0.0 %
Date:	2017-11-07	Branches:	0	30	0.0 %


/*	$OpenBSD: hcreate.c,v 1.7 2016/05/29 20:47:49 guenther Exp $	*/
/*	$NetBSD: hcreate.c,v 1.5 2004/04/23 02:48:12 simonb Exp $	*/

/*
 * Copyright (c) 2001 Christopher G. Demetriou
 * 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 for the
 *          NetBSD Project.  See http://www.NetBSD.org/ for
 *          information about NetBSD.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 *
 * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
 */

/*
 * hcreate() / hsearch() / hdestroy()
 *
 * SysV/XPG4 hash table functions.
 *
 * Implementation done based on NetBSD manual page and Solaris manual page,
 * plus my own personal experience about how they're supposed to work.
 *
 * I tried to look at Knuth (as cited by the Solaris manual page), but
 * nobody had a copy in the office, so...
 */

#include <assert.h>
#include <errno.h>
#include <stdint.h>
#include <search.h>
#include <stdlib.h>
#include <string.h>
#include <sys/queue.h>

#include <db.h>		/* for __default_hash */

#ifndef _DIAGASSERT
#define _DIAGASSERT(x)
#endif

/*
 * DO NOT MAKE THIS STRUCTURE LARGER THAN 32 BYTES (4 ptrs on 64-bit
 * ptr machine) without adjusting MAX_BUCKETS_LG2 below.
 */
struct internal_entry {
	SLIST_ENTRY(internal_entry) link;
	ENTRY ent;
};
SLIST_HEAD(internal_head, internal_entry);

#define	MIN_BUCKETS_LG2	4
#define	MIN_BUCKETS	(1 << MIN_BUCKETS_LG2)

/*
 * max * sizeof internal_entry must fit into size_t.
 * assumes internal_entry is <= 32 (2^5) bytes.
 */
#define	MAX_BUCKETS_LG2	(sizeof (size_t) * 8 - 1 - 5)
#define	MAX_BUCKETS	((size_t)1 << MAX_BUCKETS_LG2)

static struct internal_head *htable;
static size_t htablesize;

int
hcreate(size_t nel)
{
	size_t idx;
	unsigned int p2;

	/* Make sure this isn't called when a table already exists. */
	_DIAGASSERT(htable == NULL);
	if (htable != NULL) {
		errno = EINVAL;
		return 0;
	}

	/* If nel is too small, make it min sized. */
	if (nel < MIN_BUCKETS)
		nel = MIN_BUCKETS;

	/* If it's too large, cap it. */
	if (nel > MAX_BUCKETS)
		nel = MAX_BUCKETS;

	/* If it's is not a power of two in size, round up. */
	if ((nel & (nel - 1)) != 0) {
		for (p2 = 0; nel != 0; p2++)
			nel >>= 1;
		_DIAGASSERT(p2 <= MAX_BUCKETS_LG2);
		nel = 1 << p2;
	}

	/* Allocate the table. */
	htablesize = nel;
	htable = calloc(htablesize, sizeof htable[0]);
	if (htable == NULL) {
		errno = ENOMEM;
		return 0;
	}

	/* Initialize it. */
	for (idx = 0; idx < htablesize; idx++)
		SLIST_INIT(&htable[idx]);

	return 1;
}

void
hdestroy(void)
{
	struct internal_entry *ie;
	size_t idx;

	_DIAGASSERT(htable != NULL);
	if (htable == NULL)
		return;

	for (idx = 0; idx < htablesize; idx++) {
		while (!SLIST_EMPTY(&htable[idx])) {
			ie = SLIST_FIRST(&htable[idx]);
			SLIST_REMOVE_HEAD(&htable[idx], link);
			free(ie->ent.key);
			free(ie);
		}
	}
	free(htable);
	htable = NULL;
}

ENTRY *
hsearch(ENTRY item, ACTION action)
{
	struct internal_head *head;
	struct internal_entry *ie;
	uint32_t hashval;
	size_t len;

	_DIAGASSERT(htable != NULL);
	_DIAGASSERT(item.key != NULL);
	_DIAGASSERT(action == ENTER || action == FIND);

	len = strlen(item.key);
	hashval = __default_hash(item.key, len);

	head = &htable[hashval & (htablesize - 1)];
	ie = SLIST_FIRST(head);
	while (ie != NULL) {
		if (strcmp(ie->ent.key, item.key) == 0)
			break;
		ie = SLIST_NEXT(ie, link);
	}

	if (ie != NULL)
		return &ie->ent;
	else if (action == FIND)
		return NULL;

	ie = malloc(sizeof *ie);
	if (ie == NULL)
		return NULL;
	ie->ent.key = item.key;
	ie->ent.data = item.data;

	SLIST_INSERT_HEAD(head, ie, link);
	return &ie->ent;
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: hcreate.c,v 1.7 2016/05/29 20:47:49 guenther Exp $ */
2			/* $NetBSD: hcreate.c,v 1.5 2004/04/23 02:48:12 simonb Exp $ */
3
4			/*
5			* Copyright (c) 2001 Christopher G. Demetriou
6			* All rights reserved.
7			*
8			* Redistribution and use in source and binary forms, with or without
9			* modification, are permitted provided that the following conditions
10			* are met:
11			* 1. Redistributions of source code must retain the above copyright
12			* notice, this list of conditions and the following disclaimer.
13			* 2. Redistributions in binary form must reproduce the above copyright
14			* notice, this list of conditions and the following disclaimer in the
15			* documentation and/or other materials provided with the distribution.
16			* 3. All advertising materials mentioning features or use of this software
17			* must display the following acknowledgement:
18			* This product includes software developed for the
19			* NetBSD Project. See http://www.NetBSD.org/ for
20			* information about NetBSD.
21			* 4. The name of the author may not be used to endorse or promote products
22			* derived from this software without specific prior written permission.
23			*
24			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25			* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26			* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27			* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28			* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29			* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30			* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31			* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32			* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33			* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34			*
35			* <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
36			*/
37
38			/*
39			* hcreate() / hsearch() / hdestroy()
40			*
41			* SysV/XPG4 hash table functions.
42			*
43			* Implementation done based on NetBSD manual page and Solaris manual page,
44			* plus my own personal experience about how they're supposed to work.
45			*
46			* I tried to look at Knuth (as cited by the Solaris manual page), but
47			* nobody had a copy in the office, so...
48			*/
49
50			#include <assert.h>
51			#include <errno.h>
52			#include <stdint.h>
53			#include <search.h>
54			#include <stdlib.h>
55			#include <string.h>
56			#include <sys/queue.h>
57
58			#include <db.h> /* for __default_hash */
59
60			#ifndef _DIAGASSERT
61			#define _DIAGASSERT(x)
62			#endif
63
64			/*
65			* DO NOT MAKE THIS STRUCTURE LARGER THAN 32 BYTES (4 ptrs on 64-bit
66			* ptr machine) without adjusting MAX_BUCKETS_LG2 below.
67			*/
68			struct internal_entry {
69			SLIST_ENTRY(internal_entry) link;
70			ENTRY ent;
71			};
72			SLIST_HEAD(internal_head, internal_entry);
73
74			#define MIN_BUCKETS_LG2 4
75			#define MIN_BUCKETS (1 << MIN_BUCKETS_LG2)
76
77			/*
78			* max * sizeof internal_entry must fit into size_t.
79			* assumes internal_entry is <= 32 (2^5) bytes.
80			*/
81			#define MAX_BUCKETS_LG2 (sizeof (size_t) * 8 - 1 - 5)
82			#define MAX_BUCKETS ((size_t)1 << MAX_BUCKETS_LG2)
83
84			static struct internal_head *htable;
85			static size_t htablesize;
86
87			int
88			hcreate(size_t nel)
89			{
90			size_t idx;
91			unsigned int p2;
92
93			/* Make sure this isn't called when a table already exists. */
94			_DIAGASSERT(htable == NULL);
95			if (htable != NULL) {
96			errno = EINVAL;
97			return 0;
98			}
99
100			/* If nel is too small, make it min sized. */
101			if (nel < MIN_BUCKETS)
102			nel = MIN_BUCKETS;
103
104			/* If it's too large, cap it. */
105			if (nel > MAX_BUCKETS)
106			nel = MAX_BUCKETS;
107
108			/* If it's is not a power of two in size, round up. */
109			if ((nel & (nel - 1)) != 0) {
110			for (p2 = 0; nel != 0; p2++)
111			nel >>= 1;
112			_DIAGASSERT(p2 <= MAX_BUCKETS_LG2);
113			nel = 1 << p2;
114			}
115
116			/* Allocate the table. */
117			htablesize = nel;
118			htable = calloc(htablesize, sizeof htable[0]);
119			if (htable == NULL) {
120			errno = ENOMEM;
121			return 0;
122			}
123
124			/* Initialize it. */
125			for (idx = 0; idx < htablesize; idx++)
126			SLIST_INIT(&htable[idx]);
127
128			return 1;
129			}
130
131			void
132			hdestroy(void)
133			{
134			struct internal_entry *ie;
135			size_t idx;
136
137			_DIAGASSERT(htable != NULL);
138			if (htable == NULL)
139			return;
140
141			for (idx = 0; idx < htablesize; idx++) {
142			while (!SLIST_EMPTY(&htable[idx])) {
143			ie = SLIST_FIRST(&htable[idx]);
144			SLIST_REMOVE_HEAD(&htable[idx], link);
145			free(ie->ent.key);
146			free(ie);
147			}
148			}
149			free(htable);
150			htable = NULL;
151			}
152
153			ENTRY *
154			hsearch(ENTRY item, ACTION action)
155			{
156			struct internal_head *head;
157			struct internal_entry *ie;
158			uint32_t hashval;
159			size_t len;
160
161			_DIAGASSERT(htable != NULL);
162			_DIAGASSERT(item.key != NULL);
163			_DIAGASSERT(action == ENTER \|\| action == FIND);
164
165			len = strlen(item.key);
166			hashval = __default_hash(item.key, len);
167
168			head = &htable[hashval & (htablesize - 1)];
169			ie = SLIST_FIRST(head);
170			while (ie != NULL) {
171			if (strcmp(ie->ent.key, item.key) == 0)
172			break;
173			ie = SLIST_NEXT(ie, link);
174			}
175
176			if (ie != NULL)
177			return &ie->ent;
178			else if (action == FIND)
179			return NULL;
180
181			ie = malloc(sizeof *ie);
182			if (ie == NULL)
183			return NULL;
184			ie->ent.key = item.key;
185			ie->ent.data = item.data;
186
187			SLIST_INSERT_HEAD(head, ie, link);
188			return &ie->ent;
189			}