added basic login support

src/database/database.cpp

@@ -52,6 +52,18 @@ map<string, string> Database::getStrMap(const string& sql){
     return map;
 }
 
+string Database::getStr(const string& sql){
+    sqlite3_stmt* stmt = prepareStmt(sql);
+    string str;
+    if (stmt == nullptr)
+        return str; 
+
+    str = reinterpret_cast<const char*>(sqlite3_column_text(stmt, 0));
+    
+    sqlite3_finalize(stmt);
+    return str;
+}
+
 set<string> Database::getStrSet(const string& sql){
     sqlite3_stmt* stmt = prepareStmt(sql);
     set<string> vec;

src/database/database.hpp

@@ -24,6 +24,8 @@ public:
 
     std::set<std::string> getStrSet(const std::string& sql);
 
+    string getStr(const string& sql)
+
     std::map<std::string, std::string> getStrMap(const std::string& sql);
 
 private: