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diff --git a/src/mongo/db/pipeline/document_source_limit.h b/src/mongo/db/pipeline/document_source_limit.h
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+/**
+ * Copyright (C) 2016 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/db/pipeline/document_source.h"
+
+namespace mongo {
+
+class DocumentSourceLimit final : public DocumentSource, public SplittableDocumentSource {
+public:
+    // virtuals from DocumentSource
+    GetNextResult getNext() final;
+    const char* getSourceName() const final;
+    BSONObjSet getOutputSorts() final {
+        return pSource ? pSource->getOutputSorts()
+                       : SimpleBSONObjComparator::kInstance.makeBSONObjSet();
+    }
+
+    /**
+     * Attempts to combine with a subsequent $limit stage, setting 'limit' appropriately.
+     */
+    Pipeline::SourceContainer::iterator doOptimizeAt(Pipeline::SourceContainer::iterator itr,
+                                                     Pipeline::SourceContainer* container) final;
+    Value serialize(bool explain = false) const final;
+
+    GetDepsReturn getDependencies(DepsTracker* deps) const final {
+        return SEE_NEXT;  // This doesn't affect needed fields
+    }
+
+    /**
+      Create a new limiting DocumentSource.
+
+      @param pExpCtx the expression context for the pipeline
+      @returns the DocumentSource
+     */
+    static boost::intrusive_ptr<DocumentSourceLimit> create(
+        const boost::intrusive_ptr<ExpressionContext>& pExpCtx, long long limit);
+
+    // Virtuals for SplittableDocumentSource
+    // Need to run on rounter. Running on shard as well is an optimization.
+    boost::intrusive_ptr<DocumentSource> getShardSource() final {
+        return this;
+    }
+    boost::intrusive_ptr<DocumentSource> getMergeSource() final {
+        return this;
+    }
+
+    long long getLimit() const {
+        return _limit;
+    }
+    void setLimit(long long newLimit) {
+        _limit = newLimit;
+    }
+
+    /**
+      Create a limiting DocumentSource from BSON.
+
+      This is a convenience method that uses the above, and operates on
+      a BSONElement that has been deteremined to be an Object with an
+      element named $limit.
+
+      @param pBsonElement the BSONELement that defines the limit
+      @param pExpCtx the expression context
+      @returns the grouping DocumentSource
+     */
+    static boost::intrusive_ptr<DocumentSource> createFromBson(
+        BSONElement elem, const boost::intrusive_ptr<ExpressionContext>& pExpCtx);
+
+private:
+    DocumentSourceLimit(const boost::intrusive_ptr<ExpressionContext>& pExpCtx, long long limit);
+
+    long long _limit;
+    long long _nReturned = 0;
+};
+
+}  // namespace mongo