Use references as loop variables

Author: pavel-shirshov

common/ipaddresses.cpp

@@ -11,7 +11,7 @@ using namespace swss;
 IpAddresses::IpAddresses(const string &ipsStr)
 {
     auto ips = tokenize(ipsStr, IP_DELIMITER);
-    for (auto ip : ips)
+    for (const auto& ip : ips)
         m_ips.insert(ip);
 }
 
@@ -39,7 +39,7 @@ bool IpAddresses::contains(const IpAddress &ip) const
 
 bool IpAddresses::contains(const IpAddresses &ips) const
 {
-    for (auto ip : ips.getIpAddresses())
+    for (const auto& ip : ips.getIpAddresses())
     {
         if (!contains(ip))
         {

common/json.cpp

@@ -13,7 +13,7 @@ string JSon::buildJson(const vector<FieldValueTuple> &fv)
     nlohmann::json j = nlohmann::json::array();
 
     // we use array to save order
-    for (auto &i : fv)
+    for (const auto& i : fv)
     {
         j.push_back(fvField(i));
         j.push_back(fvValue(i));

common/producerstatetable.cpp

@@ -69,7 +69,7 @@ void ProducerStateTable::set(string key, vector<FieldValueTuple> &values,
 
     args.push_back("G");
     args.push_back(key);
-    for (auto& iv: values)
+    for (const auto& iv: values)
     {
         args.push_back(fvField(iv));
         args.push_back(fvValue(iv));

common/producertable.cpp

@@ -89,7 +89,7 @@ void ProducerTable::set(string key, vector<FieldValueTuple> &values, string op,
         json j;
         string json_key = getKeyName(key);
         j[json_key] = json::object();
-        for (auto it : values)
+        for (const auto& it : values)
             j[json_key][fvField(it)] = fvValue(it);
         j["OP"] = op;
         m_dumpFile << j.dump(4);

common/rediscommand.cpp

@@ -47,7 +47,7 @@ void RedisCommand::formatHMSET(const std::string &key,
 
     std::vector<const char*> args = { cmd, key.c_str() };
 
-    for (const auto &fvt: values)
+    for (const auto& fvt: values)
     {
         args.push_back(fvField(fvt).c_str());
         args.push_back(fvValue(fvt).c_str());

common/select.cpp

@@ -81,7 +81,7 @@ void Select::removeSelectable(Selectable *selectable)
 
 void Select::addSelectables(vector<Selectable *> selectables)
 {
-    for(auto it : selectables)
+    for(const auto& it : selectables)
     {
         addSelectable(it);
     }

common/subscriberstatetable.cpp

@@ -27,7 +27,7 @@ SubscriberStateTable::SubscriberStateTable(DBConnector *db, string tableName, in
     vector<string> keys;
     m_table.getKeys(keys);
 
-    for (auto key: keys)
+    for (const auto& key: keys)
     {
         KeyOpFieldsValuesTuple kco;
 
@@ -98,7 +98,7 @@ void SubscriberStateTable::pops(deque<KeyOpFieldsValuesTuple> &vkco, string /*pr
         return;
     }
 
-    while (auto event = popEventBuffer())
+    while (const auto& event = popEventBuffer())
     {
         KeyOpFieldsValuesTuple kco;
         /* if the Key-space notification is empty, try next one. */

common/table.cpp

@@ -98,7 +98,7 @@ void TableEntryEnumerable::getContent(vector<KeyOpFieldsValuesTuple> &tuples)
 
     tuples.clear();
 
-    for (auto key: keys)
+    for (const auto& key: keys)
     {
         vector<FieldValueTuple> values;
         string op = "";