1/*
2 * Copyright 2016 Jakub Klama <jceel@FreeBSD.org>
3 * All rights reserved
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted providing that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24 * POSSIBILITY OF SUCH DAMAGE.
25 *
26 */
27
28#ifndef LIB9P_HASHTABLE_H
29#define LIB9P_HASHTABLE_H
30
31#include <pthread.h>
32#include <sys/queue.h>
33
34struct ht {
35	struct ht_entry * 	ht_entries;
36	ssize_t 		ht_nentries;
37	pthread_rwlock_t	ht_rwlock;
38};
39
40struct ht_entry {
41	TAILQ_HEAD(, ht_item) hte_items;
42};
43
44struct ht_item {
45	uint32_t		hti_hash;
46	void *			hti_data;
47	TAILQ_ENTRY(ht_item)	hti_link;
48};
49
50struct ht_iter {
51	struct ht *		htit_parent;
52	struct ht_item *	htit_curr;
53	struct ht_item *	htit_next;
54	ssize_t			htit_slot;
55};
56
57#ifdef __clang__
58#pragma clang diagnostic push
59#pragma clang diagnostic ignored "-Wthread-safety-analysis"
60#endif
61
62/*
63 * Obtain read-lock on hash table.
64 */
65static inline int
66ht_rdlock(struct ht *h)
67{
68
69	return (pthread_rwlock_rdlock(&h->ht_rwlock));
70}
71
72/*
73 * Obtain write-lock on hash table.
74 */
75static inline int
76ht_wrlock(struct ht *h)
77{
78
79	return (pthread_rwlock_wrlock(&h->ht_rwlock));
80}
81
82/*
83 * Release lock on hash table.
84 */
85static inline int
86ht_unlock(struct ht *h)
87{
88
89	return (pthread_rwlock_unlock(&h->ht_rwlock));
90}
91
92#ifdef __clang__
93#pragma clang diagnostic pop
94#endif
95
96void ht_init(struct ht *h, ssize_t size);
97void ht_destroy(struct ht *h);
98void *ht_find(struct ht *h, uint32_t hash);
99void *ht_find_locked(struct ht *h, uint32_t hash);
100int ht_add(struct ht *h, uint32_t hash, void *value);
101int ht_remove(struct ht *h, uint32_t hash);
102int ht_remove_locked(struct ht *h, uint32_t hash);
103int ht_remove_at_iter(struct ht_iter *iter);
104void ht_iter(struct ht *h, struct ht_iter *iter);
105void *ht_next(struct ht_iter *iter);
106
107#endif  /* LIB9P_HASHTABLE_H */
108