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+/**
+ * Copyright (C) 2021-present MongoDB, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the Server Side Public License, version 1,
+ * as published by MongoDB, Inc.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * Server Side Public License for more details.
+ *
+ * You should have received a copy of the Server Side Public License
+ * along with this program. If not, see
+ * <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ * As a special exception, the copyright holders give permission to link the
+ * code of portions of this program with the OpenSSL library under certain
+ * conditions as described in each individual source file and distribute
+ * linked combinations including the program with the OpenSSL library. You
+ * must comply with the Server Side Public License in all respects for
+ * all of the code used other than as permitted herein. If you modify file(s)
+ * with this exception, you may extend this exception to your version of the
+ * file(s), but you are not obligated to do so. If you do not wish to do so,
+ * delete this exception statement from your version. If you delete this
+ * exception statement from all source files in the program, then also delete
+ * it in the license file.
+ */
+
+#pragma once
+
+#include <memory>
+
+#include "mongo/db/service_context.h"
+#include "mongo/platform/atomic_word.h"
+#include "mongo/util/future.h"
+#include "mongo/util/out_of_line_executor.h"
+
+namespace mongo {
+
+class CancelationToken;
+class OperationContext;
+
+/**
+ * Wrapper class around an OperationContext that calls markKilled(ErrorCodes::CallbackCanceled) when
+ * the supplied CancelationToken is canceled.
+ *
+ * This class is useful for having an OperationContext be interrupted when a CancelationToken is
+ * canceled. Note that OperationContext::getCancelationToken() is instead useful for having a
+ * CancelationToken be canceled when an OperationContext is interrupted. The combination of the two
+ * enables bridging between OperationContext interruption and CancelationToken cancellation
+ * arbitrarily.
+ *
+ * IMPORTANT: Executors are allowed to refuse work. markKilled(ErrorCodes::CallbackCanceled) won't
+ * be called when the supplied CancelationToken is canceled if the task executor has already been
+ * shut down, for example. Use a task executor bound to the process lifetime if you must guarantee
+ * that the OperationContext is interrupted when the CancelationToken is canceled.
+ */
+class CancelableOperationContext {
+public:
+ CancelableOperationContext(ServiceContext::UniqueOperationContext opCtx,
+ const CancelationToken& cancelToken,
+ ExecutorPtr executor);
+
+ CancelableOperationContext(const CancelableOperationContext&) = delete;
+ CancelableOperationContext& operator=(const CancelableOperationContext&) = delete;
+
+ CancelableOperationContext(CancelableOperationContext&&) = delete;
+ CancelableOperationContext& operator=(CancelableOperationContext&&) = delete;
+
+ ~CancelableOperationContext();
+
+ OperationContext* get() const noexcept {
+ return _opCtx.get();
+ }
+
+ OperationContext* operator->() const noexcept {
+ return get();
+ }
+
+ OperationContext& operator*() const noexcept {
+ return *get();
+ }
+
+private:
+ struct SharedBlock {
+ AtomicWord<bool> done{false};
+ };
+
+ const std::shared_ptr<SharedBlock> _sharedBlock;
+ const ServiceContext::UniqueOperationContext _opCtx;
+ const SemiFuture<void> _markKilledFinished;
+};
+
+} // namespace mongo