ring.cpp

/*
    SPDX-License-Identifier: MIT
    Copyright © 2023 Amebis
*/
 
#include "pch.h"
 
using namespace std;
#ifdef _WIN32
using namespace Microsoft::VisualStudio::CppUnitTestFramework;
#endif
 
namespace UnitTests
{
    constexpr size_t capacity = 50;
 
    TEST_CLASS(ring)
    {
    public:
        TEST_METHOD(test)
        {
            using ring_t = stdex::ring<int, capacity>;
            ring_t ring;
            thread writer([](_Inout_ ring_t& ring)
                {
                    int seed = 0;
                    for (size_t retries = 1000; retries--;) {
                        for (auto to_write = static_cast<size_t>(static_cast<uint64_t>(::rand()) * capacity / 5 / RAND_MAX); to_write;) {
                            int* ptr; size_t num_write;
                            tie(ptr, num_write) = ring.back();
                            if (to_write < num_write)
                                num_write = to_write;
                            for (size_t i = 0; i < num_write; i++)
                                ptr[i] = seed++;
                            ring.push(num_write);
                            to_write -= num_write;
                        }
                    }
                    ring.quit();
                }, ref(ring));
 
            int seed = 0;
            for (;;) {
                int* ptr; size_t num_read;
                tie(ptr, num_read) = ring.front();
                if (!ptr) _Unlikely_
                    break;
                if (num_read > 7)
                    num_read = 7;
                for (size_t i = 0; i < num_read; ++i)
                    Assert::AreEqual(seed++, ptr[i]);
                ring.pop(num_read);
            }
            writer.join();
        }
    };
}