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#pragma once
#include <atomic>
#include <memory>
namespace DB
{
/// This class helps to calculate rows_before_limit_at_least.
class RowsBeforeLimitCounter
{
public:
void add(uint64_t rows)
{
setAppliedLimit();
rows_before_limit.fetch_add(rows, std::memory_order_release);
}
void set(uint64_t rows)
{
setAppliedLimit();
rows_before_limit.store(rows, std::memory_order_release);
}
uint64_t get() const { return rows_before_limit.load(std::memory_order_acquire); }
void setAppliedLimit() { has_applied_limit.store(true, std::memory_order_release); }
bool hasAppliedLimit() const { return has_applied_limit.load(std::memory_order_acquire); }
private:
std::atomic<uint64_t> rows_before_limit = 0;
std::atomic_bool has_applied_limit = false;
};
using RowsBeforeLimitCounterPtr = std::shared_ptr<RowsBeforeLimitCounter>;
}
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