replaced += by append and changed the order of strings to remove necessitity to substring at the the end.

Author: gittiver

include/crow/http_connection.h

@@ -160,7 +160,7 @@ namespace crow
                 else if (req_.upgrade)
                 {
                     // h2 or h2c headers
-                    if (req_.get_header_value("upgrade").substr(0, 2) == "h2")
+                    if (req_.get_header_value("upgrade").find("h2")==0)
                     {
                         // TODO(ipkn): HTTP/2
                         // currently, ignore upgrade header

include/crow/http_response.h

@@ -301,7 +301,7 @@ namespace crow
 #endif
             if (file_info.statResult == 0 && S_ISREG(file_info.statbuf.st_mode))
             {
-                std::size_t last_dot = path.find_last_of(".");
+                std::size_t last_dot = path.find_last_of('.');
                 std::string extension = path.substr(last_dot + 1);
                 code = 200;
                 this->add_header("Content-Length", std::to_string(file_info.statbuf.st_size));

include/crow/query_string.h

@@ -378,10 +378,11 @@ namespace crow
             char* ret = get(name);
             if (ret != nullptr)
             {
+                const std::string key_name = name + '=';
                 for (unsigned int i = 0; i < key_value_pairs_.size(); i++)
                 {
                     std::string str_item(key_value_pairs_[i]);
-                    if (str_item.substr(0, name.size() + 1) == name + '=')
+                    if (str_item.find(key_name)==0)
                     {
                         key_value_pairs_.erase(key_value_pairs_.begin() + i);
                         break;
@@ -416,14 +417,18 @@ namespace crow
         std::vector<char*> pop_list(const std::string& name, bool use_brackets = true)
         {
             std::vector<char*> ret = get_list(name, use_brackets);
+            const size_t name_len = name.length();
             if (!ret.empty())
             {
                 for (unsigned int i = 0; i < key_value_pairs_.size(); i++)
                 {
                     std::string str_item(key_value_pairs_[i]);
-                    if ((use_brackets ? (str_item.substr(0, name.size() + 3) == name + "[]=") : (str_item.substr(0, name.size() + 1) == name + '=')))
-                    {
+                    if (str_item.find(name)==0) {
+                      if (use_brackets && str_item.find("[]=",name_len)==name_len) {
                         key_value_pairs_.erase(key_value_pairs_.begin() + i--);
+                      } else if (!use_brackets && str_item.find('=',name_len)==name_len ) {
+                           key_value_pairs_.erase(key_value_pairs_.begin() + i--);
+                       }
                     }
                 }
             }
@@ -454,13 +459,14 @@ namespace crow
         /// Works the same as \ref get_dict() but removes the values from the query string.
         std::unordered_map<std::string, std::string> pop_dict(const std::string& name)
         {
+            const std::string name_value = name +'[';
             std::unordered_map<std::string, std::string> ret = get_dict(name);
             if (!ret.empty())
             {
                 for (unsigned int i = 0; i < key_value_pairs_.size(); i++)
                 {
                     std::string str_item(key_value_pairs_[i]);
-                    if (str_item.substr(0, name.size() + 1) == name + '[')
+                    if (str_item.find(name_value)==0)
                     {
                         key_value_pairs_.erase(key_value_pairs_.begin() + i--);
                     }