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 <atf-c.h>
27#define _SEARCH_PRIVATE
28#include <search.h>
29#include <stdbool.h>
30#include <stdlib.h>
31#include <stdio.h>
32
33static int n_nodes = 0;
34static int n_seen = 0;
35
36/* Validates the integrity of an AVL tree. */
37static inline unsigned int
38tnode_assert(const posix_tnode *n)
39{
40	unsigned int height_left, height_right;
41	int balance;
42
43	if (n == NULL)
44		return 0;
45	height_left = tnode_assert(n->llink);
46	height_right = tnode_assert(n->rlink);
47	balance = (int)height_left - (int)height_right;
48	ATF_CHECK(balance >= -1);
49	ATF_CHECK(balance <= 1);
50	ATF_CHECK_EQ(balance, n->balance);
51	return (height_left > height_right ? height_left : height_right) + 1;
52}
53
54static int
55compar(const void *a, const void *b)
56{
57
58	return *(int *)a - *(int *)b;
59}
60
61static void
62treewalk(const posix_tnode *node, VISIT v, int level)
63{
64
65	if (v == postorder || v == leaf)
66		n_seen++;
67}
68
69ATF_TC_WITHOUT_HEAD(tsearch_test);
70ATF_TC_BODY(tsearch_test, tc)
71{
72	/*
73	 * Run the test below in a deterministic fashion to prevent this
74	 * test from potentially flapping. We assume that this provides
75	 * enough coverage.
76	 */
77#if 0
78	unsigned short random_state[3];
79	arc4random_buf(random_state, sizeof(random_state));
80#else
81	unsigned short random_state[3] = { 26554, 13330, 3246 };
82#endif
83
84#define NKEYS 1000
85	/* Create 1000 possible keys. */
86	int keys[NKEYS];
87	for (int i = 0; i < NKEYS; ++i)
88		keys[i] = i;
89
90	/* Apply random operations on a binary tree and check the results. */
91	posix_tnode *root = NULL;
92	bool present[NKEYS] = {};
93	for (int i = 0; i < NKEYS * 10; ++i) {
94		int key = nrand48(random_state) % NKEYS;
95		int sample = i;
96
97		/*
98		 * Ensure each case is tested at least 10 times, plus a
99		 * random sampling.
100		 */
101		if ((sample % NKEYS) > 3)
102			sample = nrand48(random_state) % 3;
103
104		switch (sample) {
105		case 0:  /* tdelete(). */
106			if (present[key]) {
107				ATF_CHECK(tdelete(&key, &root, compar) != NULL);
108				present[key] = false;
109				ATF_CHECK(n_nodes > 0);
110				n_nodes--;
111			} else {
112				ATF_CHECK_EQ(NULL,
113				    tdelete(&key, &root, compar));
114			}
115			break;
116		case 1:  /* tfind(). */
117			if (present[key]) {
118				ATF_CHECK_EQ(&keys[key],
119				    *(int **)tfind(&key, &root, compar));
120			} else {
121				ATF_CHECK_EQ(NULL, tfind(&key, &root, compar));
122			}
123			break;
124		case 2:  /* tsearch(). */
125			if (present[key]) {
126				ATF_CHECK_EQ(&keys[key],
127				    *(int **)tsearch(&key, &root, compar));
128			} else {
129				ATF_CHECK_EQ(&keys[key], *(int **)tsearch(
130				    &keys[key], &root, compar));
131				present[key] = true;
132				n_nodes++;
133			}
134			break;
135		}
136		tnode_assert(root);
137	}
138
139	/* Walk the tree. */
140	twalk(root, treewalk);
141	ATF_CHECK_EQ(n_nodes, n_seen);
142
143	/* Remove all entries from the tree. */
144	for (int key = 0; key < NKEYS; ++key)
145		if (present[key])
146			ATF_CHECK(tdelete(&key, &root, compar) != NULL);
147	ATF_CHECK_EQ(NULL, root);
148}
149
150ATF_TP_ADD_TCS(tp)
151{
152
153	ATF_TP_ADD_TC(tp, tsearch_test);
154
155	return (atf_no_error());
156}
157