LibSQL+SQLServer: Build SQLServer system service

This patch introduces the SQLServer system server. This service is
supposed to be the only process/application talking to database storage.
This makes things like locking and caching more reliable, easier to
implement, and more efficient.

In LibSQL we added a client component that does the ugly IPC nitty-
gritty for you. All that's needed is setting a number of event handler
lambdas and you can connect to databases and execute statements on them.

Applications that wish to use this SQLClient class obviously need to
link LibSQL and LibIPC.

1 files changed, 35 insertions, 0 deletions

diff --git a/Userland/Services/SQLServer/ClientConnection.h b/Userland/Services/SQLServer/ClientConnection.h
new file mode 100644
index 0000000000..96af97fe70
--- /dev/null
+++ b/Userland/Services/SQLServer/ClientConnection.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2021, Jan de Visser <jan@de-visser.net>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/HashMap.h>
+#include <LibIPC/ClientConnection.h>
+#include <SQLServer/SQLClientEndpoint.h>
+#include <SQLServer/SQLServerEndpoint.h>
+
+namespace SQLServer {
+
+class ClientConnection final
+    : public IPC::ClientConnection<SQLClientEndpoint, SQLServerEndpoint> {
+    C_OBJECT(ClientConnection);
+
+public:
+    explicit ClientConnection(NonnullRefPtr<Core::LocalSocket>, int client_id);
+    virtual ~ClientConnection() override;
+
+    virtual void die() override;
+
+    static RefPtr<ClientConnection> client_connection_for(int client_id);
+
+private:
+    virtual Messages::SQLServer::ConnectResponse connect(String const&) override;
+    virtual Messages::SQLServer::SqlStatementResponse sql_statement(int, String const&) override;
+    virtual void statement_execute(int) override;
+    virtual void disconnect(int) override;
+};
+
+}