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diff --git a/src/mongo/db/catalog/catalog_raii.h b/src/mongo/db/catalog/catalog_raii.h
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+/**
+ *    Copyright (C) 2017 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    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
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    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 GNU Affero General 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/base/string_data.h"
+#include "mongo/db/catalog/collection.h"
+#include "mongo/db/catalog/database.h"
+#include "mongo/db/concurrency/d_concurrency.h"
+#include "mongo/db/namespace_string.h"
+#include "mongo/db/operation_context.h"
+#include "mongo/db/views/view.h"
+
+namespace mongo {
+
+/**
+ * RAII-style class, which acquires a lock on the specified database in the requested mode and
+ * obtains a reference to the database. Used as a shortcut for calls to dbHolder().get().
+ *
+ * Use this when you want to do a database-level operation, like read a list of all collections, or
+ * drop a collection.
+ *
+ * It is guaranteed that the lock will be released when this object goes out of scope, therefore
+ * the database reference returned by this class should not be retained.
+ */
+class AutoGetDb {
+    MONGO_DISALLOW_COPYING(AutoGetDb);
+
+public:
+    AutoGetDb(OperationContext* opCtx, StringData ns, LockMode mode);
+    AutoGetDb(OperationContext* opCtx, StringData ns, Lock::DBLock lock);
+
+    Database* getDb() const {
+        return _db;
+    }
+
+private:
+    const Lock::DBLock _dbLock;
+    Database* const _db;
+};
+
+/**
+ * RAII-style class, which acquires a locks on the specified database and collection in the
+ * requested mode and obtains references to both.
+ *
+ * Use this when you want to access something at the collection level, but do not want to do any of
+ * the tasks associated with the 'ForRead' variants below. For example, you can use this to access a
+ * Collection's CursorManager, or to remove a document.
+ *
+ * It is guaranteed that locks will be released when this object goes out of scope, therefore
+ * the database and the collection references returned by this class should not be retained.
+ */
+class AutoGetCollection {
+    MONGO_DISALLOW_COPYING(AutoGetCollection);
+
+public:
+    enum class ViewMode { kViewsPermitted, kViewsForbidden };
+
+    AutoGetCollection(OperationContext* opCtx, const NamespaceString& nss, LockMode modeAll)
+        : AutoGetCollection(opCtx, nss, modeAll, modeAll, ViewMode::kViewsForbidden) {}
+
+    AutoGetCollection(OperationContext* opCtx,
+                      const NamespaceString& nss,
+                      LockMode modeDB,
+                      LockMode modeColl)
+        : AutoGetCollection(opCtx, nss, modeDB, modeColl, ViewMode::kViewsForbidden) {}
+
+    AutoGetCollection(OperationContext* opCtx,
+                      const NamespaceString& nss,
+                      const UUID& uuid,
+                      LockMode modeAll);
+
+    AutoGetCollection(OperationContext* opCtx,
+                      const NamespaceString& nss,
+                      LockMode modeColl,
+                      ViewMode viewMode,
+                      Lock::DBLock lock);
+
+    /**
+     * This constructor is intended for internal use and should not be used outside this file.
+     * AutoGetCollectionForReadCommand and AutoGetCollectionOrViewForReadCommand use 'viewMode' to
+     * determine whether or not it is permissible to obtain a handle on a view namespace. Use
+     * another constructor or another 'AutoGet' class instead.
+     */
+    AutoGetCollection(OperationContext* opCtx,
+                      const NamespaceString& nss,
+                      LockMode modeDB,
+                      LockMode modeColl,
+                      ViewMode viewMode);
+
+    /**
+     * Returns nullptr if the database didn't exist.
+     */
+    Database* getDb() const {
+        return _autoDb.getDb();
+    }
+
+    /**
+     * Returns nullptr if the collection didn't exist.
+     */
+    Collection* getCollection() const {
+        return _coll;
+    }
+
+private:
+    const ViewMode _viewMode;
+    const AutoGetDb _autoDb;
+    const Lock::CollectionLock _collLock;
+
+    Collection* const _coll;
+};
+
+/**
+ * RAII-style class which acquires the appropriate hierarchy of locks for a collection or
+ * view. The pointer to a view definition is nullptr if it does not exist.
+ *
+ * Use this when you have not yet determined if the namespace is a view or a collection.
+ * For example, you can use this to access a namespace's CursorManager.
+ *
+ * It is guaranteed that locks will be released when this object goes out of scope, therefore
+ * the view returned by this class should not be retained.
+ */
+class AutoGetCollectionOrView {
+    MONGO_DISALLOW_COPYING(AutoGetCollectionOrView);
+
+public:
+    AutoGetCollectionOrView(OperationContext* opCtx, const NamespaceString& nss, LockMode modeAll);
+
+    /**
+     * Returns nullptr if the database didn't exist.
+     */
+    Database* getDb() const {
+        return _autoColl.getDb();
+    }
+
+    /**
+     * Returns nullptr if the collection didn't exist.
+     */
+    Collection* getCollection() const {
+        return _autoColl.getCollection();
+    }
+
+    /**
+     * Returns nullptr if the view didn't exist.
+     */
+    ViewDefinition* getView() const {
+        return _view.get();
+    }
+
+private:
+    const AutoGetCollection _autoColl;
+    std::shared_ptr<ViewDefinition> _view;
+};
+
+/**
+ * RAII-style class, which acquires a lock on the specified database in the requested mode and
+ * obtains a reference to the database, creating it was non-existing. Used as a shortcut for
+ * calls to dbHolder().openDb(), taking care of locking details. The requested mode must be
+ * MODE_IX or MODE_X. If the database needs to be created, the lock will automatically be
+ * reacquired as MODE_X.
+ *
+ * Use this when you are about to perform a write, and want to create the database if it doesn't
+ * already exist.
+ *
+ * It is guaranteed that locks will be released when this object goes out of scope, therefore
+ * the database reference returned by this class should not be retained.
+ */
+class AutoGetOrCreateDb {
+    MONGO_DISALLOW_COPYING(AutoGetOrCreateDb);
+
+public:
+    AutoGetOrCreateDb(OperationContext* opCtx, StringData ns, LockMode mode);
+
+    Database* getDb() const {
+        return _db;
+    }
+
+    bool justCreated() const {
+        return _justCreated;
+    }
+
+    Lock::DBLock& lock() {
+        return _dbLock;
+    }
+
+private:
+    Lock::DBLock _dbLock;  // not const, as we may need to relock for implicit create
+    Database* _db;
+    bool _justCreated;
+};
+
+}  // namespace mongo