xref: /freebsd/lib/libc/stdlib/hcreate.c (revision 559a218c9b257775fb249b67945fe4a05b7a6b9f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2015 Nuxi, https://nuxi.nl/
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <search.h>
29 #include <stdbool.h>
30 #include <stddef.h>
31 
32 /*
33  * Thread unsafe interface: use a single process-wide hash table and
34  * forward calls to *_r() functions.
35  */
36 
37 static struct hsearch_data global_hashtable;
38 static bool global_hashtable_initialized = false;
39 
40 int
hcreate(size_t nel)41 hcreate(size_t nel)
42 {
43 
44 	return (1);
45 }
46 
47 void
hdestroy(void)48 hdestroy(void)
49 {
50 
51 	/* Destroy global hash table if present. */
52 	if (global_hashtable_initialized) {
53 		hdestroy_r(&global_hashtable);
54 		global_hashtable_initialized = false;
55 	}
56 }
57 
58 ENTRY *
hsearch(ENTRY item,ACTION action)59 hsearch(ENTRY item, ACTION action)
60 {
61 	ENTRY *retval;
62 
63 	/* Create global hash table if needed. */
64 	if (!global_hashtable_initialized) {
65 		if (hcreate_r(0, &global_hashtable) == 0)
66 			return (NULL);
67 		global_hashtable_initialized = true;
68 	}
69 	if (hsearch_r(item, action, &retval, &global_hashtable) == 0)
70 		return (NULL);
71 	return (retval);
72 }
73