Allow cleaner to work after database is closed.

Telegram/SourceFiles/storage/cache/storage_cache_database.cpp

@@ -39,6 +39,14 @@ void Database::close(FnMut<void()> &&done) {
 	});
 }
 
+void Database::waitForCleaner(FnMut<void()> &&done) {
+	_wrapped.with([
+		done = std::move(done)
+	](Implementation &unwrapped) mutable {
+		unwrapped.waitForCleaner(std::move(done));
+	});
+}
+
 void Database::put(
 		const Key &key,
 		QByteArray &&value,

Telegram/SourceFiles/storage/cache/storage_cache_database.h

@@ -68,6 +68,7 @@ public:
 
 	void clear(FnMut<void(Error)> &&done = nullptr);
 	void clearByTag(uint8 tag, FnMut<void(Error)> &&done = nullptr);
+	void waitForCleaner(FnMut<void()> &&done = nullptr);
 
 	~Database();
 

Telegram/SourceFiles/storage/cache/storage_cache_database_object.cpp

@@ -1167,6 +1167,7 @@ void DatabaseObject::createCleaner() {
 }
 
 void DatabaseObject::cleanerDone(Error error) {
+	invokeCallback(_cleaner.done);
 	_cleaner = CleanerWrap();
 	pushStatsDelayed();
 }
@@ -1211,6 +1212,7 @@ void DatabaseObject::clear(FnMut<void(Error)> &&done) {
 	}
 	if (key.empty()) {
 		invokeCallback(done, Error::NoError());
+		createCleaner();
 		return;
 	}
 	open(std::move(key), std::move(done));
@@ -1229,6 +1231,17 @@ void DatabaseObject::clearByTag(uint8 tag, FnMut<void(Error)> &&done) {
 	invokeCallback(done, Error::NoError());
 }
 
+void DatabaseObject::waitForCleaner(FnMut<void()> &&done) {
+	while (!_stale.empty()) {
+		clearStaleChunk();
+	}
+	if (_cleaner.object) {
+		_cleaner.done = std::move(done);
+	} else {
+		invokeCallback(done);
+	}
+}
+
 auto DatabaseObject::getManyRaw(const std::vector<Key> &keys) const
 -> std::vector<Raw> {
 	auto result = std::vector<Raw>();

Telegram/SourceFiles/storage/cache/storage_cache_database_object.h

@@ -59,6 +59,7 @@ public:
 
 	void clear(FnMut<void(Error)> &&done);
 	void clearByTag(uint8 tag, FnMut<void(Error)> &&done);
+	void waitForCleaner(FnMut<void()> &&done);
 
 	static QString BinlogFilename();
 	static QString CompactReadyFilename();
@@ -90,6 +91,7 @@ private:
 	struct CleanerWrap {
 		std::unique_ptr<Cleaner> object;
 		base::binary_guard guard;
+		FnMut<void()> done;
 	};
 	struct CompactorWrap {
 		std::unique_ptr<Compactor> object;

Telegram/SourceFiles/storage/storage_databases.cpp

@@ -90,7 +90,8 @@ void Databases::destroy(Cache::Database *database) {
 			Assert(!kept.destroying.alive());
 			auto [first, second] = base::make_binary_guard();
 			kept.destroying = std::move(first);
-			database->close([=, guard = std::move(second)]() mutable {
+			database->close();
+			database->waitForCleaner([=, guard = std::move(second)]() mutable {
 				crl::on_main([=, guard = std::move(guard)]{
 					if (!guard.alive()) {
 						return;
@@ -102,4 +103,4 @@ void Databases::destroy(Cache::Database *database) {
 	}
 }
 
-} // namespace Storage
+} // namespace Storage