121 lines
2.1 KiB
C++
121 lines
2.1 KiB
C++
#pragma once
|
|
|
|
#include <atomic>
|
|
#include <vector>
|
|
|
|
#include "transaction.hpp"
|
|
#include "transaction_store.hpp"
|
|
#include "commit_log.hpp"
|
|
|
|
#include "utils/counters/simple_counter.hpp"
|
|
#include "threading/sync/spinlock.hpp"
|
|
#include "threading/sync/lockable.hpp"
|
|
|
|
namespace tx
|
|
{
|
|
|
|
class TransactionError : std::runtime_error
|
|
{
|
|
public:
|
|
using std::runtime_error::runtime_error;
|
|
};
|
|
|
|
class Engine : Lockable<SpinLock>
|
|
{
|
|
public:
|
|
using sptr = std::shared_ptr<Engine>;
|
|
|
|
Engine() : counter(1) {}
|
|
|
|
Transaction& begin()
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
|
|
auto id = Id(counter.next());
|
|
auto t = new Transaction(id, active, *this);
|
|
|
|
active.insert(id);
|
|
store.put(id, t);
|
|
|
|
return *t;
|
|
}
|
|
|
|
Transaction& advance(const Id& id)
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
|
|
auto* t = store.get(id);
|
|
|
|
if(t == nullptr)
|
|
throw TransactionError("transaction does not exist");
|
|
|
|
// this is a new command
|
|
t->cid++;
|
|
|
|
return *t;
|
|
}
|
|
|
|
void commit(const Transaction& t)
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
clog.set_committed(t.id);
|
|
|
|
finalize(t);
|
|
}
|
|
|
|
void abort(const Transaction& t)
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
clog.set_aborted(t.id);
|
|
|
|
finalize(t);
|
|
}
|
|
|
|
Id last_known_active()
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
return active.front();
|
|
}
|
|
|
|
// total number of transactions started from the beginning of time
|
|
uint64_t count()
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
return counter.count();
|
|
}
|
|
|
|
// the number of currently active transactions
|
|
size_t size()
|
|
{
|
|
auto guard = this->acquire_unique();
|
|
return active.size();
|
|
}
|
|
|
|
CommitLog clog;
|
|
|
|
private:
|
|
void finalize(const Transaction& t)
|
|
{
|
|
active.remove(t.id);
|
|
|
|
// remove transaction from store
|
|
store.del(t.id);
|
|
}
|
|
|
|
SimpleCounter<uint64_t> counter;
|
|
Snapshot<Id> active;
|
|
TransactionStore<uint64_t> store;
|
|
};
|
|
|
|
void Transaction::commit()
|
|
{
|
|
engine.commit(*this);
|
|
}
|
|
|
|
void Transaction::abort()
|
|
{
|
|
engine.abort(*this);
|
|
}
|
|
|
|
}
|