Ticket #8629: test.cpp

#include <boost/lockfree/spsc_queue.hpp>

int main(int argc, char* argv[])
{
    using namespace boost::lockfree;

    size_t capacity=8;
    spsc_queue<unsigned char> q(capacity);
    unsigned char data[]={45, 14, 7, 34, 2}; // 5 elements
    unsigned char* dst=new unsigned char[sizeof(data)];

    // push array {45, 14, 7, 34, 2}
    q.push(data, sizeof(data));

    // read data into dst buffer
    // using size_t pop(OutputIterator it)
    // the returned count is 5
    size_t count=q.pop(dst);

    // check that data and dst are identical
    // rc is 0
    int rc=memcmp(data, dst, sizeof(data));

    // push array {45, 14, 7, 34, 2}
    // after that operation the stored data
    // consists of 2 fragments
    q.push(data, sizeof(data));

    // read data into dst buffer
    // using size_t pop(OutputIterator it)
    // the returned count is 5

    //* ERROR:
    //* If the stored data consists of 2 fragments
    //* the pop(OutputIterator it) will not work properly
    //* for random-access-iterator
    //* the second fragmet will be written starting from
    //* the same point as the first fragment:
    //* See spsc_queue.hpp:224
    //*
    //* std::copy(internal_buffer + read_index, internal_buffer + max_size, it);
    //* std::copy(internal_buffer, internal_buffer + count1, it);
    //*
    //* The code should be:
    //* it=std::copy(internal_buffer + read_index, internal_buffer + max_size, it);
    //* std::copy(internal_buffer, internal_buffer + count1, it);


    count=q.pop(dst);

    //* ERROR
    //* check that data and dst are NOT identical
    //* rc is 1
    rc=memcmp(data, dst, sizeof(data));

    delete[] dst;

    return 0;
}