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diff --git a/src/mongo/util/thread_safety_context.h b/src/mongo/util/thread_safety_context.h
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+/**
+ *    Copyright (C) 2020-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 "mongo/platform/atomic_word.h"
+
+namespace mongo {
+
+class ThreadSafetyContextTest;
+
+/**
+ * Provides a singleton object that allows enforcing a single-threaded context at startup.
+ *
+ * This class, currently, intercepts `stdx::thread` creations and aborts the process if a single
+ * threaded context is expected.
+ *
+ * You should avoid using the interfaces that specify single-threaded context (i.e.,
+ * `forbidMultiThreading()` and `allowMultiThreading()`) outside the main function.
+ *
+ * If using other APIs for spawning threads (e.g., `pthread_create()`), make sure to precede the
+ * API call with `onThreadCreate()`.
+ */
+class ThreadSafetyContext final {
+public:
+    ThreadSafetyContext(const ThreadSafetyContext&) = delete;
+
+    ThreadSafetyContext(ThreadSafetyContext&&) noexcept = delete;
+
+    ThreadSafetyContext& operator=(const ThreadSafetyContext&) = delete;
+
+    ThreadSafetyContext& operator=(ThreadSafetyContext&&) = delete;
+
+    static ThreadSafetyContext* getThreadSafetyContext() noexcept;
+
+    // Prevents a multi-threaded context -- aborts the process on thread creation.
+    // If the program is already multi-threaded, it will abort the program.
+    void forbidMultiThreading() noexcept;
+
+    // Allows a multi-threaded context by lifting the limit enforced by `forbidMultiThreading()`.
+    void allowMultiThreading() noexcept;
+
+    // Allows detecting thread creation, and thus a multi-threaded context.
+    // If not using `stdx::thread`, you must always call this method before spawning a new thread.
+    void onThreadCreate() noexcept;
+
+    // Restricts the ability of resetting the context to the unit-test fixture.
+    friend class ThreadSafetyContextTest;
+
+private:
+    // Prevents creating any instance of the object (other than the singleton).
+    ThreadSafetyContext() = default;
+
+    // An indicator on whether the program is single-threaded.
+    AtomicWord<bool> _isSingleThreaded{true};
+
+    // If set to "false", it will prevent creation of new threads.
+    AtomicWord<bool> _safeToCreateThreads{true};
+};
+
+}  // namespace mongo