86 lines
1.7 KiB
C++
86 lines
1.7 KiB
C++
#ifndef MEMGRAPH_MVCC_TRANSACTIONENGINE_HPP
|
|
#define MEMGRAPH_MVCC_TRANSACTIONENGINE_HPP
|
|
|
|
#include <cstdlib>
|
|
#include <atomic>
|
|
#include <mutex>
|
|
#include <vector>
|
|
#include <set>
|
|
#include <list>
|
|
#include <algorithm>
|
|
|
|
#include "transaction.hpp"
|
|
#include "utils/counters/simple_counter.hpp"
|
|
|
|
#include "threading/sync/spinlock.hpp"
|
|
#include "threading/sync/lockable.hpp"
|
|
|
|
class TransactionEngine : Lockable<SpinLock>
|
|
{
|
|
public:
|
|
TransactionEngine(uint64_t n) : counter(n) {}
|
|
|
|
Transaction begin()
|
|
{
|
|
auto guard = this->acquire();
|
|
|
|
auto id = counter.next();
|
|
auto t = Transaction(id, active);
|
|
|
|
active.push_back(id);
|
|
|
|
return t;
|
|
}
|
|
|
|
void commit(const Transaction& t)
|
|
{
|
|
auto guard = this->acquire();
|
|
|
|
finalize(t);
|
|
}
|
|
|
|
void rollback(const Transaction& t)
|
|
{
|
|
auto guard = this->acquire();
|
|
// what to do here?
|
|
|
|
finalize(t);
|
|
}
|
|
|
|
uint64_t last_known_active()
|
|
{
|
|
auto guard = this->acquire();
|
|
return active.front();
|
|
}
|
|
|
|
// total number of transactions started from the beginning of time
|
|
uint64_t count()
|
|
{
|
|
auto guard = this->acquire();
|
|
return counter.count();
|
|
}
|
|
|
|
// the number of currently active transactions
|
|
size_t size()
|
|
{
|
|
auto guard = this->acquire();
|
|
return active.size();
|
|
}
|
|
|
|
private:
|
|
void finalize(const Transaction& t)
|
|
{
|
|
auto x = t.id;
|
|
|
|
// remove transaction from the active transactions list
|
|
auto last = std::remove(active.begin(), active.end(), x);
|
|
active.erase(last, active.end());
|
|
}
|
|
|
|
SimpleCounter<uint64_t> counter;
|
|
|
|
std::vector<uint64_t> active;
|
|
};
|
|
|
|
#endif
|