source: mainline/uspace/lib/c/test/qsort.c@ d7f7a4a

/*
 * SPDX-FileCopyrightText: 2017 Jiri Svoboda
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <pcut/pcut.h>
#include <qsort.h>
#include <stdio.h>
#include <stdlib.h>

enum {
        /** Length of test number sequences */
        test_seq_len = 5
};

/** Test compare function.
 *
 * @param a First key
 * @param b Second key
 * @return <0, 0, >0 if @a a is less than, equal or greater than @a b
 */
static int test_cmp(const void *a, const void *b)
{
        int *ia = (int *)a;
        int *ib = (int *)b;

        return *ia - *ib;
}

static void bubble_sort(int *seq, size_t nmemb)
{
        size_t i;
        size_t j;
        int t;

        for (i = 0; i < nmemb - 1; i++)
                for (j = 0; j < nmemb - 1; j++) {
                        if (seq[j] > seq[j + 1]) {
                                t = seq[j];
                                seq[j] = seq[j + 1];
                                seq[j + 1] = t;
                        }
                }
}

PCUT_INIT;

PCUT_TEST_SUITE(qsort);

/** Test sorting already sorted increasing sequence */
PCUT_TEST(incr_seq)
{
        int *seq;
        int i;

        seq = calloc(test_seq_len, sizeof(int));
        PCUT_ASSERT_NOT_NULL(seq);

        for (i = 0; i < test_seq_len; i++)
                seq[i] = i;

        qsort(seq, test_seq_len, sizeof(int), test_cmp);

        for (i = 0; i < test_seq_len; i++) {
                PCUT_ASSERT_INT_EQUALS(i, seq[i]);
        }

        free(seq);
}

/** Test sorting reverse-sorted decreasing sequence. */
PCUT_TEST(decr_seq)
{
        int *seq;
        int i;

        seq = calloc(test_seq_len, sizeof(int));
        PCUT_ASSERT_NOT_NULL(seq);

        for (i = 0; i < test_seq_len; i++)
                seq[i] = test_seq_len - 1 - i;

        qsort(seq, test_seq_len, sizeof(int), test_cmp);

        for (i = 0; i < test_seq_len; i++) {
                PCUT_ASSERT_INT_EQUALS(i, seq[i]);
        }

        free(seq);
}

/** Test sorting reverse-sorted decreasing sequence where each member repeats twice. */
PCUT_TEST(decr2_seq)
{
        int *seq;
        int i;

        seq = calloc(test_seq_len, sizeof(int));
        PCUT_ASSERT_NOT_NULL(seq);

        for (i = 0; i < test_seq_len; i++) {
                seq[i] = (test_seq_len - 1 - i) / 2;
        }

        qsort(seq, test_seq_len, sizeof(int), test_cmp);

        for (i = 0; i < test_seq_len; i++) {
                PCUT_ASSERT_INT_EQUALS(i / 2, seq[i]);
        }

        free(seq);
}

/** Generate pseudorandom sequence. */
static int seq_next(int cur)
{
        return (cur * 1951) % 1000000;
}

/** Test sorting pseudorandom sequence. */
PCUT_TEST(pseudorandom_seq)
{
        int *seq, *seq2;
        int i;
        int v;

        seq = calloc(test_seq_len, sizeof(int));
        PCUT_ASSERT_NOT_NULL(seq);

        seq2 = calloc(test_seq_len, sizeof(int));
        PCUT_ASSERT_NOT_NULL(seq);

        v = 1;
        for (i = 0; i < test_seq_len; i++) {
                seq[i] = v;
                seq2[i] = v;
                v = seq_next(v);
        }

        qsort(seq, test_seq_len, sizeof(int), test_cmp);
        bubble_sort(seq2, test_seq_len);

        for (i = 0; i < test_seq_len; i++) {
                PCUT_ASSERT_INT_EQUALS(seq2[i], seq[i]);
        }

        free(seq);
        free(seq2);
}

PCUT_EXPORT(qsort);