peerplays_migrated/libraries/db/include/graphene/db/object_database.hpp

167 lines
7 KiB
C++

/*
* Copyright (c) 2015, Cryptonomex, Inc.
* All rights reserved.
*
* This source code is provided for evaluation in private test networks only, until September 8, 2015. After this date, this license expires and
* the code may not be used, modified or distributed for any purpose. Redistribution and use in source and binary forms, with or without modification,
* are permitted until September 8, 2015, provided that the following conditions are met:
*
* 1. The code and/or derivative works are used only for private test networks consisting of no more than 10 P2P nodes.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <graphene/db/object.hpp>
#include <graphene/db/index.hpp>
#include <graphene/db/undo_database.hpp>
#include <fc/log/logger.hpp>
#include <map>
namespace graphene { namespace db {
/**
* @class object_database
* @brief maintains a set of indexed objects that can be modified with multi-level rollback support
*/
class object_database
{
public:
object_database();
~object_database();
void reset_indexes() { _index.clear(); _index.resize(255); }
void open(const fc::path& data_dir );
/**
* Saves the complete state of the object_database to disk, this could take a while
*/
void flush();
void wipe(const fc::path& data_dir); // remove from disk
void close();
template<typename T, typename F>
const T& create( F&& constructor )
{
auto& idx = get_mutable_index<T>();
return static_cast<const T&>( idx.create( [&](object& o)
{
assert( dynamic_cast<T*>(&o) );
constructor( static_cast<T&>(o) );
} ));
}
///These methods are used to retrieve indexes on the object_database. All public index accessors are const-access only.
/// @{
template<typename IndexType>
const IndexType& get_index_type()const {
static_assert( std::is_base_of<index,IndexType>::value, "Type must be an index type" );
return static_cast<const IndexType&>( get_index( IndexType::object_type::space_id, IndexType::object_type::type_id ) );
}
template<typename T>
const index& get_index()const { return get_index(T::space_id,T::type_id); }
const index& get_index(uint8_t space_id, uint8_t type_id)const;
const index& get_index(object_id_type id)const { return get_index(id.space(),id.type()); }
/// @}
const object& get_object( object_id_type id )const;
const object* find_object( object_id_type id )const;
/// These methods are mutators of the object_database. You must use these methods to make changes to the object_database,
/// in order to maintain proper undo history.
///@{
const object& insert( object&& obj ) { return get_mutable_index(obj.id).insert( std::move(obj) ); }
void remove( const object& obj ) { get_mutable_index(obj.id).remove( obj ); }
template<typename T, typename Lambda>
void modify( const T& obj, const Lambda& m ) {
get_mutable_index(obj.id).modify(obj,m);
}
///@}
template<typename T>
static const T& cast( const object& obj )
{
assert( nullptr != dynamic_cast<const T*>(&obj) );
return static_cast<const T&>(obj);
}
template<typename T>
static T& cast( object& obj )
{
assert( nullptr != dynamic_cast<T*>(&obj) );
return static_cast<T&>(obj);
}
template<typename T>
const T& get( object_id_type id )const
{
const object& obj = get_object( id );
assert( nullptr != dynamic_cast<const T*>(&obj) );
return static_cast<const T&>(obj);
}
template<typename T>
const T* find( object_id_type id )const
{
const object* obj = find_object( id );
assert( !obj || nullptr != dynamic_cast<const T*>(obj) );
return static_cast<const T*>(obj);
}
template<uint8_t SpaceID, uint8_t TypeID, typename T>
const T* find( object_id<SpaceID,TypeID,T> id )const { return find<T>(id); }
template<uint8_t SpaceID, uint8_t TypeID, typename T>
const T& get( object_id<SpaceID,TypeID,T> id )const { return get<T>(id); }
template<typename IndexType>
IndexType* add_index()
{
typedef typename IndexType::object_type ObjectType;
if( _index[ObjectType::space_id].size() <= ObjectType::type_id )
_index[ObjectType::space_id].resize( 255 );
assert(!_index[ObjectType::space_id][ObjectType::type_id]);
unique_ptr<index> indexptr( new IndexType(*this) );
_index[ObjectType::space_id][ObjectType::type_id] = std::move(indexptr);
return static_cast<IndexType*>(_index[ObjectType::space_id][ObjectType::type_id].get());
}
void pop_undo();
fc::path get_data_dir()const { return _data_dir; }
/** public for testing purposes only... should be private in practice. */
undo_database _undo_db;
protected:
template<typename IndexType>
IndexType& get_mutable_index_type() {
static_assert( std::is_base_of<index,IndexType>::value, "Type must be an index type" );
return static_cast<IndexType&>( get_mutable_index( IndexType::object_type::space_id, IndexType::object_type::type_id ) );
}
template<typename T>
index& get_mutable_index() { return get_mutable_index(T::space_id,T::type_id); }
index& get_mutable_index(object_id_type id) { return get_mutable_index(id.space(),id.type()); }
index& get_mutable_index(uint8_t space_id, uint8_t type_id);
private:
friend class base_primary_index;
friend class undo_database;
void save_undo( const object& obj );
void save_undo_add( const object& obj );
void save_undo_remove( const object& obj );
fc::path _data_dir;
vector< vector< unique_ptr<index> > > _index;
};
} } // graphene::db