chore: import upstream snapshot with attribution

libnd4j/include/graph/SessionLocalStorage.h

@@ -0,0 +1,68 @@
+/* ******************************************************************************
+ *
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License, Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ *  See the NOTICE file distributed with this work for additional
+ *  information regarding copyright ownership.
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ******************************************************************************/
+
+//
+// @author raver119@gmail.com
+//
+
+#ifndef LIBND4J_SESSIONLOCALSTORAGE_H
+#define LIBND4J_SESSIONLOCALSTORAGE_H
+#include <memory/Workspace.h>
+
+#include <map>
+#include <thread>
+#include <unordered_map>
+
+#include "Context.h"
+#include "Stash.h"
+#include "VariableSpace.h"
+
+namespace sd {
+namespace graph {
+class SD_LIB_EXPORT SessionLocalStorage {
+ protected:
+  std::atomic<LongType> _sessionCounter;
+  SD_MAP_IMPL<LongType, LongType> _threadSession;
+  SD_MAP_IMPL<LongType, VariableSpace*> _threadVariableSpace;
+
+  VariableSpace* _variableSpace;
+  Stash* _stash;
+
+  std::mutex _mutex;
+
+  LongType getSessionId();
+  LongType getThreadId();
+
+ public:
+  SessionLocalStorage(VariableSpace* variableSpace = nullptr, Stash* stash = nullptr);
+
+  ~SessionLocalStorage();
+
+  VariableSpace* localVariableSpace();
+  VariableSpace* localVariableSpace(LongType sessionId);
+
+  LongType startSession();
+  void endSession(LongType sessionId);
+  void endSession();
+
+  int numberOfSessions();
+};
+}  // namespace graph
+}  // namespace sd
+
+#endif  // LIBND4J_SESSIONLOCALSTORAGE_H