// Copyright (c) 2016 The Bitcoin Core developers
// Copyright (c) 2017-2020 The Bitcoin developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <event2/event.h>

#ifdef EVENT_SET_MEM_FUNCTIONS_IMPLEMENTED
// It would probably be ideal to define dummy test(s) that report skipped, but
// boost::test doesn't seem to make that practical (at least not in versions
// available with common distros)

#include <support/events.h>

#include <test/setup_common.h>

#include <boost/test/unit_test.hpp>

#include <cstdlib>
#include <map>
#include <vector>

static std::map<void *, short> tags;
static std::map<void *, uint16_t> orders;
static uint16_t tagSequence = 0;

static void *tag_malloc(size_t sz) {
    void *mem = malloc(sz);
    if (!mem) {
        return mem;
    }
    tags[mem]++;
    orders[mem] = tagSequence++;
    return mem;
}

static void tag_free(void *mem) {
    tags[mem]--;
    orders[mem] = tagSequence++;
    free(mem);
}

BOOST_FIXTURE_TEST_SUITE(raii_event_tests, BasicTestingSetup)

BOOST_AUTO_TEST_CASE(raii_event_creation) {
    event_set_mem_functions(tag_malloc, realloc, tag_free);

    void *base_ptr = nullptr;
    {
        auto base = obtain_event_base();
        base_ptr = (void *)base.get();
        BOOST_CHECK(tags[base_ptr] == 1);
    }
    BOOST_CHECK(tags[base_ptr] == 0);

    void *event_ptr = nullptr;
    {
        auto base = obtain_event_base();
        auto event = obtain_event(base.get(), -1, 0, nullptr, nullptr);

        base_ptr = (void *)base.get();
        event_ptr = (void *)event.get();

        BOOST_CHECK(tags[base_ptr] == 1);
        BOOST_CHECK(tags[event_ptr] == 1);
    }
    BOOST_CHECK(tags[base_ptr] == 0);
    BOOST_CHECK(tags[event_ptr] == 0);

    event_set_mem_functions(malloc, realloc, free);
}

BOOST_AUTO_TEST_CASE(raii_event_order) {
    event_set_mem_functions(tag_malloc, realloc, tag_free);

    void *base_ptr = nullptr;
    void *event_ptr = nullptr;
    {
        auto base = obtain_event_base();
        auto event = obtain_event(base.get(), -1, 0, nullptr, nullptr);

        base_ptr = (void *)base.get();
        event_ptr = (void *)event.get();

        // base should have allocated before event
        BOOST_CHECK(orders[base_ptr] < orders[event_ptr]);
    }
    // base should be freed after event
    BOOST_CHECK(orders[base_ptr] > orders[event_ptr]);

    event_set_mem_functions(malloc, realloc, free);
}

BOOST_AUTO_TEST_SUITE_END()

#endif // EVENT_SET_MEM_FUNCTIONS_IMPLEMENTED
