2026-07-11 15:55:22 +08:00

200 lines
5.4 KiB
C++

//
// SessionImpl.h
//
// Library: Data/SQLite
// Package: SQLite
// Module: SessionImpl
//
// Definition of the SessionImpl class.
//
// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Data_SQLite_SessionImpl_INCLUDED
#define Data_SQLite_SessionImpl_INCLUDED
#include "Poco/Data/SQLite/SQLite.h"
#include "Poco/Data/SQLite/Utility.h"
#include "Poco/Data/SQLite/Connector.h"
#include "Poco/Data/SQLite/Binder.h"
#include "Poco/Data/AbstractSessionImpl.h"
#include "Poco/SharedPtr.h"
#include "Poco/Mutex.h"
extern "C"
{
typedef struct sqlite3 sqlite3;
}
namespace Poco {
namespace Data {
namespace SQLite {
class SQLite_API SessionImpl: public Poco::Data::AbstractSessionImpl<SessionImpl>
/// Implements SessionImpl interface.
{
public:
SessionImpl(const std::string& fileName,
std::size_t loginTimeout = LOGIN_TIMEOUT_DEFAULT);
/// Creates the SessionImpl. Opens a connection to the database.
~SessionImpl();
/// Destroys the SessionImpl.
Poco::SharedPtr<Poco::Data::StatementImpl> createStatementImpl();
/// Returns an SQLite StatementImpl.
void open(const std::string& connect = "");
/// Opens a connection to the Database.
///
/// An in-memory system database (sys), with a single table (dual)
/// containing single field (dummy) is attached to the database.
/// The in-memory system database is used to force change count
/// to be reset to zero on every new query (or batch of queries)
/// execution. Without this functionality, select statements
/// executions that do not return any rows return the count of
/// changes effected by the most recent insert, update or delete.
/// In-memory system database can be queried and updated but can not
/// be dropped. It may be used for other purposes
/// in the future.
void close();
/// Closes the session.
void reset();
/// Do nothing
bool isConnected() const;
/// Returns true if connected, false otherwise.
void setConnectionTimeout(std::size_t timeout);
/// Sets the session connection timeout value.
/// Timeout value is in seconds.
std::size_t getConnectionTimeout() const;
/// Returns the session connection timeout value.
/// Timeout value is in seconds.
void begin();
/// Starts a transaction.
void commit();
/// Commits and ends a transaction.
void rollback();
/// Aborts a transaction.
bool canTransact() const;
/// Returns true if session has transaction capabilities.
bool isTransaction() const;
/// Returns true iff a transaction is a transaction is in progress, false otherwise.
void setTransactionIsolation(Poco::UInt32 ti);
/// Sets the transaction isolation level.
/// Warning! In order to use TRANSACTION_READ_UNCOMMITTED isolation level, it is important
/// to keep in mind that enableSharedCache() and setThreadMode() affect connection lock behavior.
/// Eg. TRANSACTION_READ_UNCOMMITTED with enableSharedCache() and setThreadMode(THREAD_MODE_MULTI)
/// in a multiple thread, shared connection and custom code for table-lock exceptions scenario,
/// multiple connections on the same thread with TRANSACTION_READ_UNCOMMITTED will throw
/// "database locked" exception.
Poco::UInt32 getTransactionIsolation() const;
/// Returns the transaction isolation level.
bool hasTransactionIsolation(Poco::UInt32 ti) const;
/// Returns true iff the transaction isolation level corresponding
/// to the supplied bitmask is supported.
bool isTransactionIsolation(Poco::UInt32 ti) const;
/// Returns true iff the transaction isolation level corresponds
/// to the supplied bitmask.
void autoCommit(const std::string&, bool val);
/// Sets autocommit property for the session.
bool isAutoCommit(const std::string& name="") const;
/// Returns autocommit property value.
void setTransactionType(TransactionType transactionType);
/// Sets begin transaction type for the session.
TransactionType getTransactionType() const;
/// Returns begin transaction type.
const std::string& connectorName() const;
/// Returns the name of the connector.
protected:
void setConnectionTimeout(const std::string& prop, const Poco::Any& value);
Poco::Any getConnectionTimeout(const std::string& prop) const;
void setTransactionType(const std::string &prop, const Poco::Any& value);
Poco::Any getTransactionType(const std::string& prop) const;
private:
void setName();
std::string _connector;
sqlite3* _pDB;
bool _connected;
bool _isTransaction;
TransactionType _transactionType;
int _timeout;
mutable
Poco::Mutex _mutex;
static const std::string DEFERRED_BEGIN_TRANSACTION;
static const std::string EXCLUSIVE_BEGIN_TRANSACTION;
static const std::string IMMEDIATE_BEGIN_TRANSACTION;
static const std::string COMMIT_TRANSACTION;
static const std::string ABORT_TRANSACTION;
static const std::string SQLITE_READ_UNCOMMITTED;
static const std::string SQLITE_READ_COMMITTED;
Poco::UInt32 _transactionIsolationLevel;
};
//
// inlines
//
inline bool SessionImpl::canTransact() const
{
return true;
}
inline bool SessionImpl::isTransaction() const
{
return _isTransaction;
}
inline const std::string& SessionImpl::connectorName() const
{
return _connector;
}
inline std::size_t SessionImpl::getConnectionTimeout() const
{
return static_cast<std::size_t>(_timeout/1000);
}
inline TransactionType SessionImpl::getTransactionType() const
{
return _transactionType;
}
} } } // namespace Poco::Data::SQLite
#endif // Data_SQLite_SessionImpl_INCLUDED