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// https://www.boost.org/doc/libs/1_67_0/doc/html/atomic/usage_examples.html#boost_atomic.usage_examples.example_ringbuffer
#include <boost/atomic.hpp>
template <typename T, size_t Size>
class ringbuffer
{
public:
ringbuffer() : head_(0), tail_(0) {}
bool push(const T &value)
{
size_t head = head_.load(boost::memory_order_relaxed);
size_t next_head = next(head);
if (next_head == tail_.load(boost::memory_order_acquire))
return false;
ring_[head] = value;
head_.store(next_head, boost::memory_order_release);
return true;
}
bool pop(T &value)
{
size_t tail = tail_.load(boost::memory_order_relaxed);
if (tail == head_.load(boost::memory_order_acquire))
return false;
value = ring_[tail];
tail_.store(next(tail), boost::memory_order_release);
return true;
}
private:
size_t next(size_t current)
{
return (current + 1) % Size;
}
T ring_[Size];
boost::atomic<size_t> head_, tail_;
};
int main()
{
ringbuffer<int, 32> r;
// try to insert an element
if (r.push(42))
{ /* succeeded */
}
else
{ /* buffer full */
}
// try to retrieve an element
int value;
if (r.pop(value))
{ /* succeeded */
}
else
{ /* buffer empty */
}
}
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