misc.c

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/* -*- C -*- */
/*
 * Copyright (c) 2012-2020 Seagate Technology LLC and/or its Affiliates
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * For any questions about this software or licensing,
 * please email opensource@seagate.com or cortx-questions@seagate.com.
 *
 */


#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

#include "lib/types.h"   /* m0_uint128 */
#include "lib/string.h"  /* m0_startswith */
#include "lib/time.h"    /* m0_time_ t */
#include "lib/memory.h"  /* M0_ALLOC_ARR */
#include "lib/arith.h"   /* m0_rnd */
#include "ut/ut.h"       /* M0_UT_ASSERT */

#define BM_COMMON_STR "bm-majority-algorithm"

enum {
        BM_MJR_EVEN_ARR_LEN = 1000,
        BM_MJR_ODD_ARR_LEN,
};

static const struct m0_uint128 zero     = M0_UINT128(0, 0);
static const struct m0_uint128 one      = M0_UINT128(0, 1);
static const struct m0_uint128 two      = M0_UINT128(0, 2);
static const struct m0_uint128 three    = M0_UINT128(0, 3);
static const struct m0_uint128 cmax64   = M0_UINT128(0, UINT64_MAX);
static const struct m0_uint128 cmax64_1 = M0_UINT128(1, 0);
static const struct m0_uint128 cmax64_2 = M0_UINT128(1, 1);
static const struct m0_uint128 cmax128  = M0_UINT128(UINT64_MAX, UINT64_MAX);

static void uint128_add_check(const struct m0_uint128 *a,
                              const struct m0_uint128 *b,
                              const struct m0_uint128 *sum)
{
        struct m0_uint128 result;

        m0_uint128_add(&result, a, b);
        M0_UT_ASSERT(m0_uint128_eq(&result, sum));

        m0_uint128_add(&result, b, a);
        M0_UT_ASSERT(m0_uint128_eq(&result, sum));
}

static void uint128_add_ut(void)
{
        uint128_add_check(&zero,    &zero,     &zero);
        uint128_add_check(&zero,    &one,      &one);
        uint128_add_check(&one,     &one,      &two);
        uint128_add_check(&one,     &two,      &three);
        uint128_add_check(&cmax64,  &zero,     &cmax64);
        uint128_add_check(&cmax64,  &one,      &cmax64_1);
        uint128_add_check(&cmax64,  &two,      &cmax64_2);
        uint128_add_check(&cmax128, &one,      &zero);
        uint128_add_check(&cmax128, &two,      &one);
        uint128_add_check(&cmax128, &three,    &two);
        uint128_add_check(&cmax128, &cmax64_1, &cmax64);
        uint128_add_check(&cmax128, &cmax64_2, &cmax64_1);
}

/* a * b = c */
static void uint128_mul_check(uint64_t a,
                              uint64_t b,
                              const struct m0_uint128 *c)
{
        struct m0_uint128 result;

        m0_uint128_mul64(&result, a, b);
        M0_UT_ASSERT(m0_uint128_eq(&result, c));
}

static void uint128_mul_check1(uint64_t a,
                               uint64_t b,
                               const struct m0_uint128 *c)
{
        uint128_mul_check(a, b, c);
        uint128_mul_check(b, a, c);
}

static void uint128_mul_ut(void)
{
        uint128_mul_check1(0, 0, &zero);
        uint128_mul_check1(0, 1, &zero);
        uint128_mul_check1(0, UINT64_MAX, &zero);
        uint128_mul_check1(1, 1, &one);
        uint128_mul_check1(1, 2, &two);
        uint128_mul_check1(1, UINT64_MAX, &cmax64);
        uint128_mul_check1(2, UINT64_MAX, &M0_UINT128(1, UINT64_MAX - 1));
        uint128_mul_check1(3, UINT64_MAX, &M0_UINT128(2, UINT64_MAX - 2));
        uint128_mul_check1(UINT64_MAX, UINT64_MAX,
                           &M0_UINT128(UINT64_MAX - 1, 1));
        uint128_mul_check1(UINT32_MAX + 1ul, UINT32_MAX + 1ul, &cmax64_1);
        uint128_mul_check1(UINT32_MAX + 1ul, UINT64_MAX,
                           &M0_UINT128(UINT32_MAX,
                                       (uint64_t) UINT32_MAX << 32));
        uint128_mul_check1(UINT32_MAX + 2ul, UINT32_MAX, &cmax64);
}

static void test_forall_exists(void)
{
        const char s[] = "0123456789";

        M0_UT_ASSERT(m0_forall(i, sizeof s, s[i] != 'a'));
        M0_UT_ASSERT(m0_exists(i, sizeof s, s[i] == '0'));
        M0_UT_ASSERT(m0_exists(i, sizeof s, s[i] == '5'));
        M0_UT_ASSERT(m0_exists(i, sizeof s, s[i] == '9'));
        M0_UT_ASSERT(!m0_exists(i, sizeof s, s[i] == 'a'));
}

static void test_str_startswith(void)
{
        const char s[] = "foobar";

        M0_UT_ASSERT(m0_startswith("foo", s));
        M0_UT_ASSERT(m0_startswith("f", s));
        M0_UT_ASSERT(!m0_startswith("bar", s));
        M0_UT_ASSERT(!m0_startswith("foobarbaz", s));
        M0_UT_ASSERT(m0_startswith("", s));
        M0_UT_ASSERT(m0_startswith("", ""));
}

static void test_majority_ident_arr(void)
{
        struct m0_key_val *kv_arr;
        struct m0_key_val *mjr;
        uint32_t          *key_arr;
        struct m0_buf     *val_arr;
        m0_time_t          seed;
        uint32_t           i;
        uint32_t           vote_nr;

        M0_ALLOC_ARR(kv_arr, BM_MJR_ODD_ARR_LEN);
        M0_UT_ASSERT(kv_arr != NULL);
        M0_ALLOC_ARR(val_arr, BM_MJR_ODD_ARR_LEN);
        M0_UT_ASSERT(val_arr != NULL);
        M0_ALLOC_ARR(key_arr, BM_MJR_ODD_ARR_LEN);
        M0_UT_ASSERT(key_arr != NULL);

        for (i = 0; i < BM_MJR_ODD_ARR_LEN; ++i) {
                m0_buf_init(&val_arr[i], BM_COMMON_STR, strlen(BM_COMMON_STR));
        }
        for (i = 0; i < BM_MJR_ODD_ARR_LEN; ++i) {
                key_arr[i] = i;
        }
        for (i = 0; i < BM_MJR_ODD_ARR_LEN; ++i) {
                m0_key_val_init(&kv_arr[i], &M0_BUF_INIT_PTR(&key_arr[i]),
                                &val_arr[i]);
        }
        vote_nr = 0;
        mjr = m0_vote_majority_get(kv_arr, BM_MJR_ODD_ARR_LEN, m0_buf_eq,
                                   &vote_nr);
        M0_UT_ASSERT(mjr != NULL);
        M0_UT_ASSERT(vote_nr == BM_MJR_ODD_ARR_LEN);

        /* Since all values are identical, pick a random one to compare. */
        seed = m0_time_now();
        i = m0_rnd(BM_MJR_ODD_ARR_LEN, &seed);
        M0_UT_ASSERT(m0_buf_eq(&kv_arr[i].kv_val, &mjr->kv_val));
        m0_free(key_arr);
        m0_free(val_arr);
        m0_free(kv_arr);
}

static void test_majority_dist_val(void)
{
        struct m0_key_val *kv_arr;
        struct m0_key_val *mjr;
        uint32_t          *key_arr;
        uint32_t          *val_arr;
        uint32_t           i;
        uint32_t           vote_nr;

        M0_ALLOC_ARR(kv_arr, BM_MJR_ODD_ARR_LEN);
        M0_UT_ASSERT(kv_arr != NULL);
        M0_ALLOC_ARR(val_arr, BM_MJR_ODD_ARR_LEN);
        M0_UT_ASSERT(val_arr != NULL);
        M0_ALLOC_ARR(key_arr, BM_MJR_ODD_ARR_LEN);
        M0_UT_ASSERT(key_arr != NULL);

        for (i = 0; i < BM_MJR_ODD_ARR_LEN; ++i) {
                val_arr[i] = i;
        }
        for (i = 0; i < BM_MJR_ODD_ARR_LEN; ++i) {
                key_arr[i] = i;
        }
        for (i = 0; i < BM_MJR_ODD_ARR_LEN; ++i) {
                m0_key_val_init(&kv_arr[i], &M0_BUF_INIT_PTR(&key_arr[i]),
                                &M0_BUF_INIT_PTR(&val_arr[i]));
        }
        vote_nr = 0;
        mjr = m0_vote_majority_get(kv_arr, BM_MJR_ODD_ARR_LEN, m0_buf_eq,
                                   &vote_nr);
        M0_UT_ASSERT(mjr == NULL);
        M0_UT_ASSERT(vote_nr == 1);

        m0_free(key_arr);
        m0_free(val_arr);
        m0_free(kv_arr);
}

static void test_majority_tie(void)
{
        struct m0_key_val *kv_arr;
        struct m0_key_val *mjr;
        uint32_t          *key_arr;
        uint32_t          *val_arr;
        uint32_t           i;
        uint32_t           vote_nr;

        M0_ALLOC_ARR(kv_arr, BM_MJR_EVEN_ARR_LEN);
        M0_UT_ASSERT(kv_arr != NULL);
        M0_ALLOC_ARR(val_arr, BM_MJR_EVEN_ARR_LEN);
        M0_UT_ASSERT(val_arr != NULL);
        M0_ALLOC_ARR(key_arr, BM_MJR_EVEN_ARR_LEN);
        M0_UT_ASSERT(key_arr != NULL);

        for (i = 0; i < BM_MJR_EVEN_ARR_LEN; ++i) {
                val_arr[i] = i % 2;
        }
        for (i = 0; i < BM_MJR_EVEN_ARR_LEN; ++i) {
                key_arr[i] = i;
        }
        for (i = 0; i < BM_MJR_EVEN_ARR_LEN; ++i) {
                m0_key_val_init(&kv_arr[i], &M0_BUF_INIT_PTR(&key_arr[i]),
                                &M0_BUF_INIT_PTR(&val_arr[i]));
        }
        vote_nr = 0;
        mjr = m0_vote_majority_get(kv_arr, BM_MJR_EVEN_ARR_LEN, m0_buf_eq,
                                   &vote_nr);
        M0_UT_ASSERT(mjr == NULL);
        M0_UT_ASSERT(vote_nr == BM_MJR_EVEN_ARR_LEN / 2);

        m0_free(key_arr);
        m0_free(val_arr);
        m0_free(kv_arr);
}

static void test_majority_get(void)
{
        test_majority_ident_arr();
        test_majority_dist_val();
        test_majority_tie();
}

void m0_test_misc(void)
{
        uint128_add_ut();
        uint128_mul_ut();
        test_str_startswith();
        test_forall_exists();
        test_majority_get();
}

/*
 *  Local variables:
 *  c-indentation-style: "K&R"
 *  c-basic-offset: 8
 *  tab-width: 8
 *  fill-column: 79
 *  scroll-step: 1
 *  End:
 */