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#include <stdio.h>
35
36static int n_nodes = 0;
37static int n_seen = 0;
38
39/* Validates the integrity of an AVL tree. */
40static inline unsigned int
41tnode_assert(const posix_tnode *n)
42{
43	unsigned int height_left, height_right;
44	int balance;
45
46	if (n == NULL)
47		return 0;
48	height_left = tnode_assert(n->llink);
49	height_right = tnode_assert(n->rlink);
50	balance = (int)height_left - (int)height_right;
51	ATF_CHECK(balance >= -1);
52	ATF_CHECK(balance <= 1);
53	ATF_CHECK_EQ(balance, n->balance);
54	return (height_left > height_right ? height_left : height_right) + 1;
55}
56
57static int
58compar(const void *a, const void *b)
59{
60
61	return *(int *)a - *(int *)b;
62}
63
64static void
65treewalk(const posix_tnode *node, VISIT v, int level)
66{
67
68	if (v == postorder || v == leaf)
69		n_seen++;
70}
71
72ATF_TC_WITHOUT_HEAD(tsearch_test);
73ATF_TC_BODY(tsearch_test, tc)
74{
75	/*
76	 * Run the test below in a deterministic fashion to prevent this
77	 * test from potentially flapping. We assume that this provides
78	 * enough coverage.
79	 */
80#if 0
81	unsigned short random_state[3];
82	arc4random_buf(random_state, sizeof(random_state));
83#else
84	unsigned short random_state[3] = { 26554, 13330, 3246 };
85#endif
86
87#define NKEYS 1000
88	/* Create 1000 possible keys. */
89	int keys[NKEYS];
90	for (int i = 0; i < NKEYS; ++i)
91		keys[i] = i;
92
93	/* Apply random operations on a binary tree and check the results. */
94	posix_tnode *root = NULL;
95	bool present[NKEYS] = {};
96	for (int i = 0; i < NKEYS * 10; ++i) {
97		int key = nrand48(random_state) % NKEYS;
98		int sample = i;
99
100		/*
101		 * Ensure each case is tested at least 10 times, plus a
102		 * random sampling.
103		 */
104		if ((sample % NKEYS) > 3)
105			sample = nrand48(random_state) % 3;
106
107		switch (sample) {
108		case 0:  /* tdelete(). */
109			if (present[key]) {
110				ATF_CHECK(tdelete(&key, &root, compar) != NULL);
111				present[key] = false;
112				ATF_CHECK(n_nodes > 0);
113				n_nodes--;
114			} else {
115				ATF_CHECK_EQ(NULL,
116				    tdelete(&key, &root, compar));
117			}
118			break;
119		case 1:  /* tfind(). */
120			if (present[key]) {
121				ATF_CHECK_EQ(&keys[key],
122				    *(int **)tfind(&key, &root, compar));
123			} else {
124				ATF_CHECK_EQ(NULL, tfind(&key, &root, compar));
125			}
126			break;
127		case 2:  /* tsearch(). */
128			if (present[key]) {
129				ATF_CHECK_EQ(&keys[key],
130				    *(int **)tsearch(&key, &root, compar));
131			} else {
132				ATF_CHECK_EQ(&keys[key], *(int **)tsearch(
133				    &keys[key], &root, compar));
134				present[key] = true;
135				n_nodes++;
136			}
137			break;
138		}
139		tnode_assert(root);
140	}
141
142	/* Walk the tree. */
143	twalk(root, treewalk);
144	ATF_CHECK_EQ(n_nodes, n_seen);
145
146	/* Remove all entries from the tree. */
147	for (int key = 0; key < NKEYS; ++key)
148		if (present[key])
149			ATF_CHECK(tdelete(&key, &root, compar) != NULL);
150	ATF_CHECK_EQ(NULL, root);
151}
152
153ATF_TP_ADD_TCS(tp)
154{
155
156	ATF_TP_ADD_TC(tp, tsearch_test);
157
158	return (atf_no_error());
159}
160