IO: miscellaneous fixes for the XML reader/writer

src/IO/configuration_JSON.cpp

@@ -263,7 +263,7 @@ void writeConfiguration(const std::string &filename, const Config *rootConfig, b
 void writeNode(const Config *config, rapidjson::Value &rootJSONData, rapidjson::Document::AllocatorType &allocator)
 {
     // Write the options
-    for (auto &entry : config->getOptions()) {
+    for (const auto &entry : config->getOptions()) {
         const std::string &configKey   = entry.first;
         const std::string &configValue = entry.second;
 

src/IO/configuration_XML.cpp

@@ -83,14 +83,22 @@ void readNode(xmlNodePtr root, Config *config)
 */
 void writeNode(xmlTextWriterPtr writer, const Config *config, const std::string &encoding)
 {
+    int status;
+
     // Write the options
-    for (auto &entry : config->getOptions()) {
+    for (const auto &entry : config->getOptions()) {
         const std::string &key   = entry.first;
         const std::string &value = entry.second;
 
         xmlChar *elementName = encodeString(key, encoding);
         xmlChar *elementText = encodeString(value, encoding);
         int status = xmlTextWriterWriteFormatElement(writer, BAD_CAST elementName, "%s", elementText);
+        if (elementText) {
+            xmlFree(elementText);
+        }
+        if (elementName) {
+            xmlFree(elementName);
+        }
         if (status < 0) {
             throw std::runtime_error("Error at xmlTextWriterWriteFormatElement");
         }
@@ -103,7 +111,10 @@ void writeNode(xmlTextWriterPtr writer, const Config *config, const std::string
 
         // Start the section
         xmlChar *elementName = encodeString(key, encoding);
-        int status = xmlTextWriterStartElement(writer, BAD_CAST elementName);
+        status = xmlTextWriterStartElement(writer, BAD_CAST elementName);
+        if (elementName) {
+            xmlFree(elementName);
+        }
         if (status < 0) {
             throw std::runtime_error("Error at xmlTextWriterStartElement");
         }
@@ -194,8 +205,7 @@ void readConfiguration(const std::string &filename, const std::string &rootname,
     }
 
     // Check if the version is supported
-    const xmlChar *versionAttributeName =
-        reinterpret_cast<const xmlChar *>("version");
+    const xmlChar *versionAttributeName = reinterpret_cast<const xmlChar *>("version");
     if (checkVersion && xmlHasProp(rootElement, versionAttributeName)) {
         xmlChar *versionValue = xmlGetProp(rootElement, versionAttributeName);
         std::string versionString((char *) versionValue);
@@ -250,6 +260,9 @@ void writeConfiguration(const std::string &filename, const std::string &rootname
     // Start the root element
     xmlChar *elementName = encodeString(rootname, DEFAULT_ENCODING);
     status = xmlTextWriterStartElement(writer, BAD_CAST elementName);
+    if (elementName) {
+        xmlFree(elementName);
+    }
     if (status < 0) {
         throw std::runtime_error("Error at xmlTextWriterStartElement");
     }
@@ -260,6 +273,9 @@ void writeConfiguration(const std::string &filename, const std::string &rootname
 
     xmlChar *versionAttr = encodeString(versionStream.str(), DEFAULT_ENCODING);
     status = xmlTextWriterWriteAttribute(writer, BAD_CAST "version", BAD_CAST versionAttr);
+    if (versionAttr) {
+        xmlFree(versionAttr);
+    }
     if (status < 0) {
         throw std::runtime_error("Error at xmlTextWriterWriteAttribute");
     }

src/IO/configuration_config.cpp

@@ -78,13 +78,6 @@ Config & Config::operator=(Config other)
     return *this;
 }
 
-/*!
-    Destructor.
-*/
-Config::~Config()
-{
-}
-
 /*!
     Swap operator.
 
@@ -158,7 +151,7 @@ bool Config::hasOption(const std::string &key) const
     \param key is the name of the option
     \result The specified option.
 */
-std::string Config::get(const std::string &key) const
+const std::string & Config::get(const std::string &key) const
 {
     return m_options->at(key);
 }
@@ -408,15 +401,15 @@ void Config::dump(std::ostream &out, int indentLevel) const
     out << std::endl;
     out << indent << "Options..." << std::endl;
     if (getOptionCount() > 0) {
-        for (auto &entry : getOptions()) {
+        for (const auto &entry : getOptions()) {
             out << indent << padding << entry.first << " = " << entry.second << std::endl;
         }
     } else {
         out << indent << padding << "No options." << std::endl;
     }
 
     ++indentLevel;
-    for (auto &entry : getSections()) {
+    for (const auto &entry : getSections()) {
         out << std::endl;
         out << indent << padding << "::: Section " << entry.first << " :::" << std::endl;
         entry.second->dump(out, indentLevel);

src/IO/configuration_config.hpp

@@ -48,7 +48,7 @@ class Config
     Config & operator=(Config other);
     Config & operator=(Config &&other) = default;
 
-    virtual ~Config();
+    virtual ~Config() = default;
 
     void swap(Config &other);
 
@@ -58,7 +58,7 @@ class Config
     Options & getOptions();
     const Options & getOptions() const;
     bool hasOption(const std::string &key) const;
-    std::string get(const std::string &key) const;
+    const std::string & get(const std::string &key) const;
     std::string get(const std::string &key, const std::string &fallback) const;
     void set(const std::string &key, const std::string &value);
     bool removeOption(const std::string &key);