a bug fix, reorganization and 0.5.1

src/serializer/serializer.hpp

@@ -0,0 +1,163 @@
+/*
+ * LMDB Abstraction Layer.
+ * Copyright (C) 2023  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 LMDBAL_SERIALIZER_HPP
+#define LMDBAL_SERIALIZER_HPP
+
+#include "serializer.h"
+
+/**
+ * \class LMDBAL::Serializer
+ * \brief A class handling serialization/deserialization
+ *
+ * A class that is constructed in every LMDBAL::Storage
+ * to serialize or deserialize keys and values.
+ *
+ * It serializes to and deserializes from <a class="el" href="http://www.lmdb.tech/doc/group__mdb.html#structMDB__val">MDB_val</a>
+ *
+ * \tparam K type of the keys of the storage
+ * \tparam V type of the values of the storage
+ */
+
+/**
+ * \brief Creates an empty Serializer
+ */
+template<class T>
+LMDBAL::Serializer<T>::Serializer() :
+    bytes(),
+    buffer(&bytes),
+    stream(&buffer)
+{
+    buffer.open(QIODevice::ReadWrite);
+}
+
+/**
+ * \brief Creates a Serializer with some data in it
+ *
+ * The data automatically gets serialized
+ *
+ * \param[in]   value   - a value that is assigned to the serializer
+ */
+template<class T>
+LMDBAL::Serializer<T>::Serializer(const T& value) :
+    bytes(),
+    buffer(&bytes),
+    stream(&buffer)
+{
+    buffer.open(QIODevice::ReadWrite);
+    _setData(value);
+}
+
+/**
+ * \brief Destoys the serializer
+ */
+template<class T>
+LMDBAL::Serializer<T>::~Serializer() {
+    buffer.close();
+}
+
+/**
+ * \brief Sets the data to the seriazer
+ *
+ * This is a normal way to seriaze value
+ *
+ * \param[in]   value   - a value you want to serialize
+ *
+ * \returns serialized value
+ */
+template<class T>
+MDB_val LMDBAL::Serializer<T>::setData(const T& value) {
+    clear();
+    _setData(value);
+    return getData();
+}
+
+/**
+ * \brief Deserializes value
+ *
+ * This is a normal way to deseriaze value
+ *
+ * \param[in]   value   - a value you want to deserialize
+ *
+ * \returns deserialized value
+ */
+template<class T>
+T LMDBAL::Serializer<T>::deserialize(const MDB_val& value) {
+    T result;
+    deserialize(value, result);
+
+    return result;
+}
+
+/**
+ * \brief Deserializes value
+ *
+ * This is a normal way to deseriaze value
+ *
+ * \param[in]   value   - a value you want to deserialize
+ * \param[out]  result  - deserialized value
+ */
+template<class T>
+void LMDBAL::Serializer<T>::deserialize(const MDB_val& value, T& result) {
+    clear();
+    bytes.setRawData((char*)value.mv_data, value.mv_size);
+    stream >> result;
+}
+
+/**
+ * \brief Private function that handles serialization
+ *
+ * \param[in]   value   - a value you want to serialize
+ */
+template<class T>
+void LMDBAL::Serializer<T>::_setData(const T& value) {
+    stream << value;
+}
+
+/**
+ * \brief Clears the state of serializer
+ *
+ * Normally you don't need to call this function
+ */
+template<class T>
+void LMDBAL::Serializer<T>::clear() {
+    if (buffer.pos() > 0) {
+        buffer.seek(0);
+    }
+}
+
+/**
+ * \brief Returns the data if it already was serialized
+ *
+ * Normally you don't need to call this function
+ *
+ * This may be usefull if you called LMDBAL::Serilizer::setData() but lost the result
+ *
+ * \returns Serialized data
+ */
+template<class T>
+MDB_val LMDBAL::Serializer<T>::getData() {
+    MDB_val val;
+
+    val.mv_size = buffer.pos();
+    val.mv_data = (char*)bytes.data();
+
+    return val;
+}
+
+#endif //LMDBAL_SERIALIZER_HPP