add comment and fix type to remove warning

Author: Murmele

include/libdbc/message.hpp

@@ -11,6 +11,12 @@ namespace libdbc {
 		Message() = delete;
 		explicit Message(uint32_t id, const std::string& name, uint8_t size, const std::string& node);
 
+        /*!
+         * \brief parseSignals
+         * \param data
+         * \param values
+         * \return
+         */
         bool parseSignals(const std::vector<uint8_t> data, std::vector<double> &values) const;
 
         void appendSignal(const Signal& signal);

src/message.cpp

@@ -142,7 +142,7 @@ namespace libdbc {
         std::sort(m_signals.begin(), m_signals.end());
 
         uint32_t curr_bit = 0;
-        for (int i=0; i < m_signals.size(); i++) {
+        for (std::vector<Signal>::size_type i=0; i < m_signals.size(); i++) {
             const auto& signal = m_signals.at(i);
             if (signal.is_multiplexed)
                 break; // Not supported yet