1 files changed, 135 insertions, 139 deletions

diff --git a/src/mongo/db/pipeline/document_source_cursor.cpp b/src/mongo/db/pipeline/document_source_cursor.cpp
index d862663363d..702852f53b2 100644
--- a/src/mongo/db/pipeline/document_source_cursor.cpp
+++ b/src/mongo/db/pipeline/document_source_cursor.cpp
@@ -43,179 +43,175 @@
 
 namespace mongo {
 
-    using boost::intrusive_ptr;
-    using std::shared_ptr;
-    using std::string;
+using boost::intrusive_ptr;
+using std::shared_ptr;
+using std::string;
 
-    DocumentSourceCursor::~DocumentSourceCursor() {
-        dispose();
-    }
-
-    const char *DocumentSourceCursor::getSourceName() const {
-        return "$cursor";
-    }
+DocumentSourceCursor::~DocumentSourceCursor() {
+    dispose();
+}
 
-    boost::optional<Document> DocumentSourceCursor::getNext() {
-        pExpCtx->checkForInterrupt();
+const char* DocumentSourceCursor::getSourceName() const {
+    return "$cursor";
+}
 
-        if (_currentBatch.empty()) {
-            loadBatch();
+boost::optional<Document> DocumentSourceCursor::getNext() {
+    pExpCtx->checkForInterrupt();
 
-            if (_currentBatch.empty()) // exhausted the cursor
-                return boost::none;
-        }
+    if (_currentBatch.empty()) {
+        loadBatch();
 
-        Document out = _currentBatch.front();
-        _currentBatch.pop_front();
-        return out;
+        if (_currentBatch.empty())  // exhausted the cursor
+            return boost::none;
     }
 
-    void DocumentSourceCursor::dispose() {
-        // Can't call in to PlanExecutor or ClientCursor registries from this function since it
-        // will be called when an agg cursor is killed which would cause a deadlock.
-        _exec.reset();
-        _currentBatch.clear();
-    }
-
-    void DocumentSourceCursor::loadBatch() {
-        if (!_exec) {
-            dispose();
-            return;
-        }
+    Document out = _currentBatch.front();
+    _currentBatch.pop_front();
+    return out;
+}
 
-        // We have already validated the sharding version when we constructed the PlanExecutor
-        // so we shouldn't check it again.
-        const NamespaceString nss(_ns);
-        AutoGetCollectionForRead autoColl(pExpCtx->opCtx, nss);
+void DocumentSourceCursor::dispose() {
+    // Can't call in to PlanExecutor or ClientCursor registries from this function since it
+    // will be called when an agg cursor is killed which would cause a deadlock.
+    _exec.reset();
+    _currentBatch.clear();
+}
 
-        _exec->restoreState(pExpCtx->opCtx);
+void DocumentSourceCursor::loadBatch() {
+    if (!_exec) {
+        dispose();
+        return;
+    }
 
-        int memUsageBytes = 0;
-        BSONObj obj;
-        PlanExecutor::ExecState state;
-        while ((state = _exec->getNext(&obj, NULL)) == PlanExecutor::ADVANCED) {
-            if (_dependencies) {
-                _currentBatch.push_back(_dependencies->extractFields(obj));
-            }
-            else {
-                _currentBatch.push_back(Document::fromBsonWithMetaData(obj));
-            }
+    // We have already validated the sharding version when we constructed the PlanExecutor
+    // so we shouldn't check it again.
+    const NamespaceString nss(_ns);
+    AutoGetCollectionForRead autoColl(pExpCtx->opCtx, nss);
+
+    _exec->restoreState(pExpCtx->opCtx);
+
+    int memUsageBytes = 0;
+    BSONObj obj;
+    PlanExecutor::ExecState state;
+    while ((state = _exec->getNext(&obj, NULL)) == PlanExecutor::ADVANCED) {
+        if (_dependencies) {
+            _currentBatch.push_back(_dependencies->extractFields(obj));
+        } else {
+            _currentBatch.push_back(Document::fromBsonWithMetaData(obj));
+        }
 
-            if (_limit) {
-                if (++_docsAddedToBatches == _limit->getLimit()) {
-                    break;
-                }
-                verify(_docsAddedToBatches < _limit->getLimit());
+        if (_limit) {
+            if (++_docsAddedToBatches == _limit->getLimit()) {
+                break;
             }
+            verify(_docsAddedToBatches < _limit->getLimit());
+        }
 
-            memUsageBytes += _currentBatch.back().getApproximateSize();
+        memUsageBytes += _currentBatch.back().getApproximateSize();
 
-            if (memUsageBytes > MaxBytesToReturnToClientAtOnce) {
-                // End this batch and prepare PlanExecutor for yielding.
-                _exec->saveState();
-                return;
-            }
+        if (memUsageBytes > MaxBytesToReturnToClientAtOnce) {
+            // End this batch and prepare PlanExecutor for yielding.
+            _exec->saveState();
+            return;
         }
+    }
 
-        // If we got here, there won't be any more documents, so destroy the executor. Can't use
-        // dispose since we want to keep the _currentBatch.
-        _exec.reset();
-
-        uassert(16028, str::stream() << "collection or index disappeared when cursor yielded: "
-                                     << WorkingSetCommon::toStatusString(obj),
-                state != PlanExecutor::DEAD);
+    // If we got here, there won't be any more documents, so destroy the executor. Can't use
+    // dispose since we want to keep the _currentBatch.
+    _exec.reset();
 
-        uassert(17285, str::stream() << "cursor encountered an error: "
-                                     << WorkingSetCommon::toStatusString(obj),
-                state != PlanExecutor::FAILURE);
+    uassert(16028,
+            str::stream() << "collection or index disappeared when cursor yielded: "
+                          << WorkingSetCommon::toStatusString(obj),
+            state != PlanExecutor::DEAD);
 
-        massert(17286, str::stream() << "Unexpected return from PlanExecutor::getNext: " << state,
-                state == PlanExecutor::IS_EOF || state == PlanExecutor::ADVANCED);
-    }
+    uassert(
+        17285,
+        str::stream() << "cursor encountered an error: " << WorkingSetCommon::toStatusString(obj),
+        state != PlanExecutor::FAILURE);
 
-    void DocumentSourceCursor::setSource(DocumentSource *pSource) {
-        /* this doesn't take a source */
-        verify(false);
-    }
+    massert(17286,
+            str::stream() << "Unexpected return from PlanExecutor::getNext: " << state,
+            state == PlanExecutor::IS_EOF || state == PlanExecutor::ADVANCED);
+}
 
-    long long DocumentSourceCursor::getLimit() const {
-        return _limit ? _limit->getLimit() : -1;
-    }
+void DocumentSourceCursor::setSource(DocumentSource* pSource) {
+    /* this doesn't take a source */
+    verify(false);
+}
 
-    bool DocumentSourceCursor::coalesce(const intrusive_ptr<DocumentSource>& nextSource) {
-        // Note: Currently we assume the $limit is logically after any $sort or
-        // $match. If we ever pull in $match or $sort using this method, we
-        // will need to keep track of the order of the sub-stages.
+long long DocumentSourceCursor::getLimit() const {
+    return _limit ? _limit->getLimit() : -1;
+}
 
-        if (!_limit) {
-            _limit = dynamic_cast<DocumentSourceLimit*>(nextSource.get());
-            return _limit.get(); // false if next is not a $limit
-        }
-        else {
-            return _limit->coalesce(nextSource);
-        }
+bool DocumentSourceCursor::coalesce(const intrusive_ptr<DocumentSource>& nextSource) {
+    // Note: Currently we assume the $limit is logically after any $sort or
+    // $match. If we ever pull in $match or $sort using this method, we
+    // will need to keep track of the order of the sub-stages.
 
-        return false;
+    if (!_limit) {
+        _limit = dynamic_cast<DocumentSourceLimit*>(nextSource.get());
+        return _limit.get();  // false if next is not a $limit
+    } else {
+        return _limit->coalesce(nextSource);
     }
 
-    Value DocumentSourceCursor::serialize(bool explain) const {
-        // we never parse a documentSourceCursor, so we only serialize for explain
-        if (!explain)
-            return Value();
+    return false;
+}
 
-        // Get planner-level explain info from the underlying PlanExecutor.
-        BSONObjBuilder explainBuilder;
-        {
-            const NamespaceString nss(_ns);
-            AutoGetCollectionForRead autoColl(pExpCtx->opCtx, nss);
+Value DocumentSourceCursor::serialize(bool explain) const {
+    // we never parse a documentSourceCursor, so we only serialize for explain
+    if (!explain)
+        return Value();
 
-            massert(17392, "No _exec. Were we disposed before explained?", _exec);
+    // Get planner-level explain info from the underlying PlanExecutor.
+    BSONObjBuilder explainBuilder;
+    {
+        const NamespaceString nss(_ns);
+        AutoGetCollectionForRead autoColl(pExpCtx->opCtx, nss);
 
-            _exec->restoreState(pExpCtx->opCtx);
-            Explain::explainStages(_exec.get(), ExplainCommon::QUERY_PLANNER, &explainBuilder);
-            _exec->saveState();
-        }
+        massert(17392, "No _exec. Were we disposed before explained?", _exec);
 
-        MutableDocument out;
-        out["query"] = Value(_query);
+        _exec->restoreState(pExpCtx->opCtx);
+        Explain::explainStages(_exec.get(), ExplainCommon::QUERY_PLANNER, &explainBuilder);
+        _exec->saveState();
+    }
 
-        if (!_sort.isEmpty())
-            out["sort"] = Value(_sort);
+    MutableDocument out;
+    out["query"] = Value(_query);
 
-        if (_limit)
-            out["limit"] = Value(_limit->getLimit());
+    if (!_sort.isEmpty())
+        out["sort"] = Value(_sort);
 
-        if (!_projection.isEmpty())
-            out["fields"] = Value(_projection);
+    if (_limit)
+        out["limit"] = Value(_limit->getLimit());
 
-        // Add explain results from the query system into the agg explain output.
-        BSONObj explainObj = explainBuilder.obj();
-        invariant(explainObj.hasField("queryPlanner"));
-        out["queryPlanner"] = Value(explainObj["queryPlanner"]);
+    if (!_projection.isEmpty())
+        out["fields"] = Value(_projection);
 
-        return Value(DOC(getSourceName() << out.freezeToValue()));
-    }
+    // Add explain results from the query system into the agg explain output.
+    BSONObj explainObj = explainBuilder.obj();
+    invariant(explainObj.hasField("queryPlanner"));
+    out["queryPlanner"] = Value(explainObj["queryPlanner"]);
 
-    DocumentSourceCursor::DocumentSourceCursor(const string& ns,
-                                               const std::shared_ptr<PlanExecutor>& exec,
-                                               const intrusive_ptr<ExpressionContext> &pCtx)
-        : DocumentSource(pCtx)
-        , _docsAddedToBatches(0)
-        , _ns(ns)
-        , _exec(exec)
-    {}
-
-    intrusive_ptr<DocumentSourceCursor> DocumentSourceCursor::create(
-            const string& ns,
-            const std::shared_ptr<PlanExecutor>& exec,
-            const intrusive_ptr<ExpressionContext> &pExpCtx) {
-        return new DocumentSourceCursor(ns, exec, pExpCtx);
-    }
+    return Value(DOC(getSourceName() << out.freezeToValue()));
+}
 
-    void DocumentSourceCursor::setProjection(
-            const BSONObj& projection,
-            const boost::optional<ParsedDeps>& deps) {
-        _projection = projection;
-        _dependencies = deps;
-    }
+DocumentSourceCursor::DocumentSourceCursor(const string& ns,
+                                           const std::shared_ptr<PlanExecutor>& exec,
+                                           const intrusive_ptr<ExpressionContext>& pCtx)
+    : DocumentSource(pCtx), _docsAddedToBatches(0), _ns(ns), _exec(exec) {}
+
+intrusive_ptr<DocumentSourceCursor> DocumentSourceCursor::create(
+    const string& ns,
+    const std::shared_ptr<PlanExecutor>& exec,
+    const intrusive_ptr<ExpressionContext>& pExpCtx) {
+    return new DocumentSourceCursor(ns, exec, pExpCtx);
+}
+
+void DocumentSourceCursor::setProjection(const BSONObj& projection,
+                                         const boost::optional<ParsedDeps>& deps) {
+    _projection = projection;
+    _dependencies = deps;
+}
 }