xref: /freebsd/lib/libc/tests/stdlib/tsearch_test.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
1 /*-
2  * Copyright (c) 2015 Nuxi, https://nuxi.nl/
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <atf-c.h>
30 #define _SEARCH_PRIVATE
31 #include <search.h>
32 #include <stdbool.h>
33 #include <stdlib.h>
34 
35 /* Validates the integrity of an AVL tree. */
36 static inline unsigned int
37 tnode_assert(const node_t *n)
38 {
39 	unsigned int height_left, height_right;
40 	int balance;
41 
42 	if (n == NULL)
43 		return 0;
44 	height_left = tnode_assert(n->llink);
45 	height_right = tnode_assert(n->rlink);
46 	balance = (int)height_left - (int)height_right;
47 	ATF_CHECK(balance >= -1);
48 	ATF_CHECK(balance <= 1);
49 	ATF_CHECK_EQ(balance, n->balance);
50 	return (height_left > height_right ? height_left : height_right) + 1;
51 }
52 
53 static int
54 compar(const void *a, const void *b)
55 {
56 
57 	return *(int *)a - *(int *)b;
58 }
59 
60 ATF_TC_WITHOUT_HEAD(tsearch_test);
61 ATF_TC_BODY(tsearch_test, tc)
62 {
63 	/*
64 	 * Run the test below in a deterministic fashion to prevent this
65 	 * test from potentially flapping. We assume that this provides
66 	 * enough coverage.
67 	 */
68 #if 0
69 	unsigned short random_state[3];
70 	arc4random_buf(random_state, sizeof(random_state));
71 #else
72 	unsigned short random_state[3] = { 26554, 13330, 3246 };
73 #endif
74 
75 #define NKEYS 1000
76 	/* Create 1000 possible keys. */
77 	int keys[NKEYS];
78 	for (int i = 0; i < NKEYS; ++i)
79 		keys[i] = i;
80 
81 	/* Apply random operations on a binary tree and check the results. */
82 	void *root = NULL;
83 	bool present[NKEYS] = {};
84 	for (int i = 0; i < NKEYS * 10; ++i) {
85 		int key = nrand48(random_state) % NKEYS;
86 		switch (nrand48(random_state) % 3) {
87 		case 0:  /* tdelete(). */
88 			if (present[key]) {
89 				ATF_CHECK(tdelete(&key, &root, compar) != NULL);
90 				present[key] = false;
91 			} else {
92 				ATF_CHECK_EQ(NULL,
93 				    tdelete(&key, &root, compar));
94 			}
95 			break;
96 		case 1:  /* tfind(). */
97 			if (present[key]) {
98 				ATF_CHECK_EQ(&keys[key],
99 				    *(int **)tfind(&key, &root, compar));
100 			} else {
101 				ATF_CHECK_EQ(NULL, tfind(&key, &root, compar));
102 			}
103 			break;
104 		case 2:  /* tsearch(). */
105 			if (present[key]) {
106 				ATF_CHECK_EQ(&keys[key],
107 				    *(int **)tsearch(&key, &root, compar));
108 			} else {
109 				ATF_CHECK_EQ(&keys[key], *(int **)tsearch(
110 				    &keys[key], &root, compar));
111 				present[key] = true;
112 			}
113 			break;
114 		}
115 		tnode_assert(root);
116 	}
117 
118 	/* Remove all entries from the tree. */
119 	for (int key = 0; key < NKEYS; ++key)
120 		if (present[key])
121 			ATF_CHECK(tdelete(&key, &root, compar) != NULL);
122 	ATF_CHECK_EQ(NULL, root);
123 }
124 
125 ATF_TP_ADD_TCS(tp)
126 {
127 
128 	ATF_TP_ADD_TC(tp, tsearch_test);
129 
130 	return (atf_no_error());
131 }
132