Add first version

First version of C++ SDL API.

Refer README file for instructions how to generate API documentation.

Current version will find database via environment variables, thus RIC
DBaaS service must be up and running before starting the application
pod which uses SDL C++ API.

Change-Id: Ia3c95ac856b293827b680a9f6451a229f69f35f9
Signed-off-by: Rolf Badorek <rolf.badorek@nokia.com>
diff --git a/src/createlogger.cpp b/src/createlogger.cpp
new file mode 100644
index 0000000..cd85f02
--- /dev/null
+++ b/src/createlogger.cpp
@@ -0,0 +1,52 @@
+/*
+   Copyright (c) 2018-2019 Nokia.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+#include "config.h"
+#include <memory>
+#include <string>
+#include "private/createlogger.hpp"
+#if HAVE_SYSTEMLOGGER
+#include "private/systemlogger.hpp"
+#endif
+
+using namespace shareddatalayer;
+
+std::shared_ptr<Logger> shareddatalayer::createLogger(const std::string& prefix)
+{
+#if HAVE_SYSTEMLOGGER
+    return std::shared_ptr<Logger>(new SystemLogger(prefix));
+#else
+#error "Need to compile with at least one logging backend"
+#endif
+}
+
+void shareddatalayer::logDebugOnce(const std::string& msg) noexcept
+{
+    auto logger(createLogger(SDL_LOG_PREFIX));
+    logger->debug() << msg;
+}
+
+void shareddatalayer::logErrorOnce(const std::string& msg) noexcept
+{
+    auto logger(createLogger(SDL_LOG_PREFIX));
+    logger->error() << msg;
+}
+
+void shareddatalayer::logInfoOnce(const std::string& msg) noexcept
+{
+    auto logger(createLogger(SDL_LOG_PREFIX));
+    logger->info() << msg;
+}