RAII transactions

src/transaction.cpp

@@ -0,0 +1,71 @@
+#include "transaction.h"
+
+LMDBAL::Transaction::Transaction():
+    txn(nullptr),
+    active(false),
+    parent(nullptr)
+{}
+
+LMDBAL::Transaction::Transaction(TransactionID txn, const Base* parent) :
+    txn(txn),
+    active(true),
+    parent(parent)
+{}
+
+LMDBAL::Transaction::Transaction(Transaction&& other):
+    txn(other.txn),
+    active(other.active),
+    parent(other.parent)
+{
+    other.active = false;
+}
+
+LMDBAL::Transaction::~Transaction() {
+    terminate();
+}
+
+LMDBAL::Transaction& LMDBAL::Transaction::operator=(Transaction&& other) {
+    terminate();
+
+    txn = other.txn;
+    active = other.active;
+    parent = other.parent;
+
+    other.active = false;
+
+    return *this;
+}
+
+void LMDBAL::Transaction::terminate() {
+    if (active) {
+        parent->abortTransaction(txn);
+        active = false;
+    }
+}
+
+bool LMDBAL::Transaction::isActive() const {
+    return active;      //todo may be it's better if I query it from DB?
+}
+
+LMDBAL::WriteTransaction::WriteTransaction(TransactionID txn, Base* parent):
+    Transaction(txn, parent)
+{}
+
+LMDBAL::WriteTransaction::WriteTransaction():
+    Transaction()
+{}
+
+LMDBAL::WriteTransaction::WriteTransaction(WriteTransaction&& other):
+    Transaction(std::move(other))
+{}
+
+void LMDBAL::WriteTransaction::abort() {
+    terminate();
+}
+
+void LMDBAL::WriteTransaction::commit() {
+    if (active) {
+        const_cast<Base*>(parent)->commitTransaction(txn);
+        active = false;
+    }
+}