Fix #70 - Interfaces are released twice after commit(), rollback(), close(), free() and detach()

src/fb-cpp/Attachment.cpp

@@ -83,7 +83,7 @@ void Attachment::disconnectOrDrop(bool drop)
 	else
 		handle->detach(&statusWrapper);
 
-	handle.reset();
+	handle.release();
 }
 
 

src/fb-cpp/Batch.cpp

@@ -227,7 +227,7 @@ void Batch::close()
 {
 	assert(isValid());
 	handle->close(&statusWrapper);
-	handle.reset();
+	handle.release();
 }
 
 FbRef<fb::IMessageMetadata> Batch::getInputMetadata()

src/fb-cpp/Blob.cpp

@@ -238,13 +238,13 @@ void Blob::cancel()
 	assert(isValid());
 
 	handle->cancel(&statusWrapper);
-	handle.reset();
+	handle.release();
 }
 
 void Blob::close()
 {
 	assert(isValid());
 
 	handle->close(&statusWrapper);
-	handle.reset();
+	handle.release();
 }

src/fb-cpp/EventListener.cpp

@@ -343,7 +343,7 @@ void EventListener::cancelEventsHandle()
 
 	{  // scope
 		std::lock_guard mutexGuard{mutex};
-		handle = eventsHandle;
+		handle = std::move(eventsHandle);
 	}
 
 	if (!handle)
@@ -352,4 +352,5 @@ void EventListener::cancelEventsHandle()
 	StatusWrapper statusWrapper{client};
 
 	handle->cancel(&statusWrapper);
+	handle.release();
 }

src/fb-cpp/ServiceManager.cpp

@@ -192,5 +192,5 @@ void ServiceManager::detachHandle()
 
 	StatusWrapper statusWrapper{*client};
 	handle->detach(&statusWrapper);
-	handle.reset();
+	handle.release();
 }

src/fb-cpp/SmartPtrs.h

@@ -61,7 +61,6 @@ namespace fbcpp
 		return FbUniquePtr<T>{obj};
 	}
 
-	// FIXME: Review every usage to see if is not leaking one reference count.
 	///
 	/// Reference-counted smart pointer for Firebird objects using addRef/release semantics.
 	///
@@ -123,6 +122,18 @@ namespace fbcpp
 			assign(p, false);
 		}
 
+		///
+		/// Relinquishes ownership of the pointer without releasing it and returns it.
+		/// Used after Firebird calls that already release the interface on success, like
+		/// `ITransaction::commit()` or `IAttachment::detach()`.
+		///
+		T* release() noexcept
+		{
+			T* tmp = ptr;
+			ptr = nullptr;
+			return tmp;
+		}
+
 		FbRef& operator=(FbRef& r) noexcept
 		{
 			assign(r.ptr, true);

src/fb-cpp/Statement.cpp

@@ -238,12 +238,12 @@ void Statement::free()
 	if (resultSetHandle)
 	{
 		resultSetHandle->close(&statusWrapper);
-		resultSetHandle.reset();
+		resultSetHandle.release();
 	}
 
 	currentRow = false;
 	statementHandle->free(&statusWrapper);
-	statementHandle.reset();
+	statementHandle.release();
 }
 
 std::string Statement::getLegacyPlan()
@@ -268,7 +268,7 @@ bool Statement::execute(Transaction& transaction)
 	if (resultSetHandle)
 	{
 		resultSetHandle->close(&statusWrapper);
-		resultSetHandle.reset();
+		resultSetHandle.release();
 	}
 
 	currentRow = false;

src/fb-cpp/Transaction.cpp

@@ -203,7 +203,7 @@ void Transaction::rollback()
 	StatusWrapper statusWrapper{client};
 
 	handle->rollback(&statusWrapper);
-	handle.reset();
+	handle.release();
 	state = TransactionState::ROLLED_BACK;
 }
 
@@ -215,7 +215,7 @@ void Transaction::commit()
 	StatusWrapper statusWrapper{client};
 
 	handle->commit(&statusWrapper);
-	handle.reset();
+	handle.release();
 	state = TransactionState::COMMITTED;
 }
 

src/fb-cpp/request/Request.cpp

@@ -93,7 +93,7 @@ namespace fbcpp::request
 		assert(isValid());
 
 		handle->free(&statusWrapper);
-		handle.reset();
+		handle.release();
 	}
 
 	void Request::start(Transaction& transaction, unsigned level)

src/test/HandleRelease.cpp

@@ -0,0 +1,148 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2026 Adriano dos Santos Fernandes
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "TestUtil.h"
+#include "fb-cpp/Blob.h"
+#include "fb-cpp/ServiceManager.h"
+#include "fb-cpp/Statement.h"
+#include "fb-cpp/Transaction.h"
+
+
+BOOST_AUTO_TEST_SUITE(HandleReleaseSuite)
+
+namespace
+{
+	// Holds two extra references to a Firebird interface around a call that ends its life.
+	// released() returns how many references the call gave back and drops the extra ones.
+	class ReleaseProbe final
+	{
+	public:
+		// Takes the temporary reference returned by getHandle() methods and drops it before counting.
+		template <typename T>
+		explicit ReleaseProbe(FbRef<T> handle)
+			: ptr{handle.get()}
+		{
+			handle.reset();
+
+			ptr->addRef();
+			before = ptr->release();
+			ptr->addRef();
+			ptr->addRef();
+		}
+
+	public:
+		int released()
+		{
+			const int after = ptr->release();
+
+			if (after > 0)
+				ptr->release();
+
+			return before + 1 - after;
+		}
+
+	private:
+		fb::IReferenceCounted* ptr;
+		int before = 0;
+	};
+
+	ServiceManagerOptions makeServiceManagerOptions()
+	{
+		auto options = ServiceManagerOptions{};
+
+		if (const auto server = getServer())
+			options.setServer(server.value());
+
+		return options;
+	}
+}  // namespace
+
+BOOST_AUTO_TEST_CASE(handlesReleasedOnce)
+{
+	const auto database = getTempFile("HandleRelease-handlesReleasedOnce.fdb");
+
+	Attachment attachment{getClient(), database, AttachmentOptions().setCreateDatabase(true).setForcedWrites(false)};
+
+	{  // scope
+		Transaction transaction{attachment};
+		ReleaseProbe probe{transaction.getHandle()};
+		transaction.commit();
+		BOOST_CHECK_EQUAL(probe.released(), 1);
+	}
+
+	{  // scope
+		Transaction transaction{attachment};
+		ReleaseProbe probe{transaction.getHandle()};
+		transaction.rollback();
+		BOOST_CHECK_EQUAL(probe.released(), 1);
+	}
+
+	{  // scope
+		Transaction transaction{attachment};
+		Statement statement{attachment, transaction, "select 1 from rdb$database"};
+
+		statement.execute(transaction);
+		ReleaseProbe reexecutedResultSet{statement.getResultSetHandle()};
+		statement.execute(transaction);
+		BOOST_CHECK_EQUAL(reexecutedResultSet.released(), 1);
+
+		ReleaseProbe resultSet{statement.getResultSetHandle()};
+		ReleaseProbe stmt{statement.getStatementHandle()};
+		statement.free();
+		BOOST_CHECK_EQUAL(resultSet.released(), 1);
+		BOOST_CHECK_EQUAL(stmt.released(), 1);
+
+		Blob closedBlob{attachment, transaction};
+		ReleaseProbe closedBlobProbe{closedBlob.getHandle()};
+		closedBlob.close();
+		BOOST_CHECK_EQUAL(closedBlobProbe.released(), 1);
+
+		Blob cancelledBlob{attachment, transaction};
+		ReleaseProbe cancelledBlobProbe{cancelledBlob.getHandle()};
+		cancelledBlob.cancel();
+		BOOST_CHECK_EQUAL(cancelledBlobProbe.released(), 1);
+
+		transaction.commit();
+	}
+
+	{  // scope
+		Attachment second{getClient(), database};
+		ReleaseProbe probe{second.getHandle()};
+		second.disconnect();
+		BOOST_CHECK_EQUAL(probe.released(), 1);
+	}
+
+	{  // scope
+		ServiceManager manager{getClient(), makeServiceManagerOptions()};
+		ReleaseProbe probe{manager.getHandle()};
+		manager.disconnect();
+		BOOST_CHECK_EQUAL(probe.released(), 1);
+	}
+
+	ReleaseProbe probe{attachment.getHandle()};
+	attachment.dropDatabase();
+	BOOST_CHECK_EQUAL(probe.released(), 1);
+}
+
+BOOST_AUTO_TEST_SUITE_END()