blue/lmdbal
1
0
Fork 1
Code Issues 1 Pull Requests Actions Packages Projects Releases 9 Wiki Activity

just some thoughts about serializer

Browse Source
This commit is contained in:
Blue 2022-09-12 18:16:18 +03:00
parent c491793387
commit d67a3c32eb
Signed by: blue
GPG Key ID: 9B203B252A63EE38
6 changed files with 163 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
database.h
View File

@ -30,6 +30,8 @@ namespace Core {
class DataBase
{
class _Table;
template<class T>
class Serializer;
public:
template <class K, class V>
class Table;

24
main.cpp
View File

@ -3,6 +3,28 @@
#include "database.h"
#include "table.h"
template<class T>
class Serializer {
public:
Serializer(const T& value):val(value) {}
void print() {
std::cout << val << std::endl;
}
T val;
};
template<>
class Serializer<int> {
public:
Serializer(int v): value(v) {}
int value;
};
int main(int argc, char **argv) {
Core::DataBase base("test1");
@ -13,5 +35,7 @@ int main(int argc, char **argv) {
table1->addRecord(1, 2);
return 0;
}

52
serializer.h Normal file
View File

@ -0,0 +1,52 @@
// Squawk messenger.
// Copyright (C) 2019 Yury Gubich <blue@macaw.me>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#ifndef CORE_DATABASE_SERIALIZER_H
#define CORE_DATABASE_SERIALIZER_H
#include <QByteArray>
#include <QBuffer>
#include <QDataStream>
#include "database.h"
namespace Core {
template<class T>
class DataBase::Serializer
{
public:
Serializer();
Serializer(const T& value);
~Serializer();
MDB_val setData(const T& value);
MDB_val getData();
void clear();
private:
void _setData(const T& value);
private:
QByteArray bytes;
QBuffer buffer;
QDataStream stream;
};
}
#endif // CORE_DATABASE_SERIALIZER_H

70
serializer.hpp Normal file
View File

@ -0,0 +1,70 @@
// Squawk messenger.
// Copyright (C) 2019 Yury Gubich <blue@macaw.me>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#include "serializer.h"
template<class T>
Core::DataBase::Serializer<T>::Serializer() :
bytes(),
buffer(&bytes),
stream(&buffer)
{
buffer.open(QIODevice::WriteOnly);
}
template<class T>
Core::DataBase::Serializer<T>::Serializer(const T& value) :
bytes(),
buffer(&bytes),
stream(&buffer)
{
buffer.open(QIODevice::WriteOnly);
_setValue(value);
}
template<class T>
Core::DataBase::Serializer<T>::~Serializer() {
buffer.close();
}
template<class T>
MDB_val Core::DataBase::Serializer<T>::setData(const T& value) {
clear();
_setValue(value);
return getValue();
}
template<class T>
void Core::DataBase::Serializer<T>::_setData(const T& value) {
stream << value;
}
template<class T>
void Core::DataBase::Serializer<T>::clear() {
if (buffer.pos() > 0) {
buffer.seek(0);
}
}
template<class T>
MDB_val Core::DataBase::Serializer<T>::getData() {
MDB_val val;
val.mv_size = buffer.pos();
val.mv_data = (uint8_t*)bytes.data();
return val;
}

11
table.h
View File

@ -18,6 +18,7 @@
#define CORE_TABLE_H
#include "database.h"
#include "serializer.h"
namespace Core {
@ -44,16 +45,14 @@ public:
void changeRecord(const K& key, const V& value);
void removeRecord(const K& key);
V getRecord(const K& key) const;
private:
Serializer<K> keySerializer;
Serializer<V> valueSerializer;
};
}
MDB_val& operator << (MDB_val& data, const QString& value);
MDB_val& operator >> (MDB_val& data, QString& value);
MDB_val& operator << (MDB_val& data, const uint32_t& value);
MDB_val& operator >> (MDB_val& data, uint32_t& value);
namespace std {
std::string to_string(const QString& str);
}

42
table.hpp
View File

@ -22,7 +22,9 @@
template<typename K, typename V>
Core::DataBase::Table<K, V>::Table(const std::string& p_name, Core::DataBase* parent):
_Table(p_name, parent)
_Table(p_name, parent),
keySerializer(),
valueSerializer()
{
}
@ -36,9 +38,8 @@ void Core::DataBase::Table<K, V>::addRecord(const K& key, const V& value) {
throw Closed("addRecord", db->name, name);
}
MDB_val lmdbKey, lmdbData;
lmdbKey << key;
lmdbData << value;
MDB_val lmdbKey = keySerializer.setData(key);
MDB_val lmdbData = valueSerializer.setData(value);
MDB_txn *txn;
mdb_txn_begin(db->environment, NULL, 0, &txn);
int rc;
@ -63,9 +64,8 @@ void Core::DataBase::Table<K, V>::changeRecord(const K& key, const V& value) {
throw Closed("changeRecord", db->name, name);
}
MDB_val lmdbKey, lmdbData;
lmdbKey << key;
lmdbData << value;
MDB_val lmdbKey = keySerializer.setData(key);
MDB_val lmdbData = valueSerializer.setData(value);
MDB_txn *txn;
mdb_txn_begin(db->environment, NULL, 0, &txn);
int rc;
@ -86,8 +86,8 @@ V Core::DataBase::Table<K, V>::getRecord(const K& key) const {
throw Closed("getRecord", db->name, name);
}
MDB_val lmdbKey, lmdbData;
lmdbKey << key;
MDB_val lmdbKey = keySerializer.setData(key);
MDB_val lmdbData;
MDB_txn *txn;
int rc;
@ -115,8 +115,7 @@ void Core::DataBase::Table<K, V>::removeRecord(const K& key) {
throw Closed("removeRecord", db->name, name);
}
MDB_val lmdbKey;
lmdbKey << key;
MDB_val lmdbKey = keySerializer.setData(key);
MDB_txn *txn;
int rc;
@ -134,27 +133,6 @@ void Core::DataBase::Table<K, V>::removeRecord(const K& key) {
}
}
MDB_val& operator << (MDB_val& data, const QString& value) {
QByteArray ba = value.toUtf8();
data.mv_size = ba.size();
data.mv_data = ba.data();
return data;
}
MDB_val& operator >> (MDB_val& data, QString& value) {
value = QString::fromUtf8((const char*)data.mv_data, data.mv_size);
return data;
}
MDB_val& operator << (MDB_val& data, const uint32_t& value) {
data.mv_size = 4;
data.mv_data = &value;
return data;
}
MDB_val& operator >> (MDB_val& data, uint32_t& value) {
std::memcpy(&value, data.mv_data, data.mv_size);
return data;
}
std::string std::to_string(const QString& str) {
return str.toStdString();
}