Moved logging functions into OSD/Logger.cpp (eventually logging system will be reworked entirely) and added new config tree structure (not yet used).

Makefiles/Makefile.SDL.Win32.GCC

@@ -119,7 +119,8 @@ endif
 #
 # Objects and Dependencies
 #
-OBJ = $(OBJ_DIR)/PPCDisasm.o $(OBJ_DIR)/Games.o $(OBJ_DIR)/Config.o $(OBJ_DIR)/INIFile.o $(OBJ_DIR)/BlockFile.o $(OBJ_DIR)/93C46.o \
+OBJ = $(OBJ_DIR)/Format.o $(OBJ_DIR)/NewConfig.o \
+  $(OBJ_DIR)/PPCDisasm.o $(OBJ_DIR)/Games.o $(OBJ_DIR)/Config.o $(OBJ_DIR)/INIFile.o $(OBJ_DIR)/BlockFile.o $(OBJ_DIR)/93C46.o \
 	$(OBJ_DIR)/ROMLoad.o $(OBJ_DIR)/unzip.o $(OBJ_DIR)/ioapi.o $(OBJ_DIR)/Error.o $(OBJ_DIR)/glew.o $(OBJ_DIR)/Shader.o \
 	$(OBJ_DIR)/Real3D.o $(OBJ_DIR)/Legacy3D.o $(OBJ_DIR)/Models.o $(OBJ_DIR)/TextureRefs.o \
 	$(OBJ_DIR)/New3D.o $(OBJ_DIR)/Mat4.o $(OBJ_DIR)/Model.o $(OBJ_DIR)/PolyHeader.o $(OBJ_DIR)/Texture.o $(OBJ_DIR)/TextureSheet.o $(OBJ_DIR)/VBO.o $(OBJ_DIR)/Vec.o $(OBJ_DIR)/R3DShader.o $(OBJ_DIR)/R3DFloat.o \
@@ -135,7 +136,7 @@ OBJ = $(OBJ_DIR)/PPCDisasm.o $(OBJ_DIR)/Games.o $(OBJ_DIR)/Config.o $(OBJ_DIR)/I
 	$(OBJ_DIR)/amp_layer2.o $(OBJ_DIR)/amp_layer3.o $(OBJ_DIR)/amp_misc2.o $(OBJ_DIR)/amp_position.o $(OBJ_DIR)/amp_transform.o \
 	$(OBJ_DIR)/amp_util.o \
 	$(OBJ_DIR)/Crypto.o \
-	$(OBJ_DIR)/Format.o
+	$(OBJ_DIR)/Logger.o
 
 
 # If built-in debugger enabled, include all debugging classes
@@ -157,6 +158,10 @@ ppcd: $(BIN_DIR) $(OBJ_DIR)
 	$(CXX) Src/CPU/PowerPC/PPCDisasm.cpp $(CPPFLAGS) -DSTANDALONE -o $(OBJ_DIR)/ppcd.o
 	$(LD) -o $(BIN_DIR)/ppcd.exe -mconsole $(OBJ_DIR)/ppcd.o
 
+tests: $(BIN_DIR) $(OBJ_DIR) $(OBJ) Src/Util/Test_Config.cpp
+	$(CXX) Src/Util/Test_Config.cpp $(CPPFLAGS) -o $(OBJ_DIR)/Test_Config.o
+	$(LD) -o $(BIN_DIR)/test_config.exe -mconsole $(OBJ_DIR)/Test_Config.o $(OBJ_DIR)/Format.o $(OBJ_DIR)/NewConfig.o $(OBJ_DIR)/Logger.o
+
 $(BIN_DIR):
 	mkdir $(BIN_DIR)
 	

Src/OSD/Logger.cpp

@@ -0,0 +1,45 @@
+#include "OSD/Logger.h"
+
+// Logger object is used to redirect log messages appropriately
+static CLogger *s_Logger = NULL;
+
+CLogger *GetLogger()
+{
+  return s_Logger;
+}
+
+void SetLogger(CLogger *Logger)
+{
+  s_Logger = Logger;
+}
+
+void DebugLog(const char *fmt, ...)
+{
+  if (s_Logger == NULL)
+    return;
+  va_list vl;
+  va_start(vl, fmt);
+  s_Logger->DebugLog(fmt, vl);
+  va_end(vl);
+}
+
+void InfoLog(const char *fmt, ...)
+{
+  if (s_Logger == NULL)
+    return;
+  va_list vl;
+  va_start(vl, fmt);
+  s_Logger->InfoLog(fmt, vl);
+  va_end(vl);
+}
+
+bool ErrorLog(const char *fmt, ...)
+{
+  if (s_Logger == NULL)
+    return FAIL;
+  va_list vl;
+  va_start(vl, fmt);
+  s_Logger->ErrorLog(fmt, vl);
+  va_end(vl);
+  return FAIL;
+}

Src/OSD/Logger.h

@@ -239,8 +239,8 @@ private:
 /******************************************************************************
  Log Functions
  
- Message logging interface. All messages are passed by the OSD layer to the
- currently active logger object.
+ Message logging interface. All messages are passed to the currently active 
+ logger object.
 ******************************************************************************/
 
 /*

Src/OSD/SDL/Main.cpp

@@ -63,59 +63,10 @@
 #include "WinOutputs.h"
 #endif
 
-
-/******************************************************************************
- Error and Debug Logging
-******************************************************************************/
-
 // Log file names
 #define DEBUG_LOG_FILE  "debug.log"
 #define ERROR_LOG_FILE  "error.log"
 
-// Logger object is used to redirect log messages appropriately
-static CLogger *s_Logger = NULL;
-
-CLogger *GetLogger()
-{
-  return s_Logger;
-}
-
-void SetLogger(CLogger *Logger)
-{
-  s_Logger = Logger;
-}
-
-void DebugLog(const char *fmt, ...)
-{
-  if (s_Logger == NULL)
-    return;
-  va_list vl;
-  va_start(vl, fmt);
-  s_Logger->DebugLog(fmt, vl);
-  va_end(vl);
-}
-
-void InfoLog(const char *fmt, ...)
-{
-  if (s_Logger == NULL)
-    return;
-  va_list vl;
-  va_start(vl, fmt);
-  s_Logger->InfoLog(fmt, vl);
-  va_end(vl);
-}
-
-bool ErrorLog(const char *fmt, ...)
-{
-  if (s_Logger == NULL)
-    return FAIL;
-  va_list vl;
-  va_start(vl, fmt);
-  s_Logger->ErrorLog(fmt, vl);
-  va_end(vl);
-  return FAIL;
-}
-
 
 /******************************************************************************
  Display Management
@@ -1549,9 +1500,9 @@ static void PrintGameList(void)
  *
  * Program entry point.
  */
+
 int main(int argc, char **argv)
 {
-
 #ifdef SUPERMODEL_DEBUGGER
   bool      cmdEnterDebugger = false;
 #endif // SUPERMODEL_DEBUGGER

Src/Util/Format.cpp

@@ -1,10 +1,33 @@
 #include "Util/Format.h"
+#include <cctype>
 
 namespace Util
 {
+  std::string TrimWhiteSpace(const std::string &str)
+  {
+    if (str.empty())
+      return std::string();
+    size_t first = 0;
+    for (; first < str.length(); ++first)
+    {
+      if (!isspace(str[first]))
+        break;
+    }
+    if (first >= str.length())
+      return std::string();
+    size_t last = str.length() - 1;
+    for (; last > first; --last)
+    {
+      if (!isspace(str[last]))
+        break;
+    }
+    ++last;
+    return std::string(str.c_str() + first, last - first);
+  }
+
   static const char hex_digits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
 
-  const std::string Hex(uint32_t n, size_t num_digits)
+  std::string Hex(uint32_t n, size_t num_digits)
   {
     Util::Format f;
     f << "0x";
@@ -16,17 +39,17 @@ namespace Util
     return f;
   }
 
-  const std::string Hex(uint32_t n)
+  std::string Hex(uint32_t n)
   {
     return Hex(n, 8);
   }
   
-  const std::string Hex(uint16_t n)
+  std::string Hex(uint16_t n)
   {
     return Hex(n, 4);
   }
   
-  const std::string Hex(uint8_t n)
+  std::string Hex(uint8_t n)
   {
     return Hex(n, 2);
   }

Src/Util/Format.h

@@ -84,10 +84,11 @@ namespace Util
     }
   };
   
-  const std::string Hex(uint32_t n, size_t num_digits);
-  const std::string Hex(uint32_t n);
-  const std::string Hex(uint16_t n);
-  const std::string Hex(uint8_t n);
+  std::string TrimWhiteSpace(const std::string &str);
+  std::string Hex(uint32_t n, size_t num_digits);
+  std::string Hex(uint32_t n);
+  std::string Hex(uint16_t n);
+  std::string Hex(uint8_t n);
 } // Util
 
 #endif  // INCLUDED_FORMAT_H

Src/Util/NewConfig.cpp

@@ -0,0 +1,372 @@
+/*
+ * Config Tree
+ * -----------
+ *
+ * A hierarchical data structure supporting arbitrary nesting. Each node
+ * (Config::Node) has a key and either a value or children (in fact, it may
+ * have both, but this does not make semantic sense and so the config tree 
+ * builders take care not to allow it).
+ *
+ * All values are simply strings for now. They may have defaults, which are 
+ * actually supplied by the caller and returned when a queried node cannot be
+ * found.
+ *
+ * Nodes at the same nesting level (siblings) are strung together in a
+ * linked list. Parents also maintain pointers to the first and last of their
+ * children (for order-preserving iteration) as well as a map for direct 
+ * lookup by key.
+ *
+ * Keys may be reused at a given level. Key-value pairs will have their order
+ * preserved when iterated but only the most recent key is returned in direct
+ * map lookups.
+ *
+ * Example:
+ *
+ *  <game name="scud">
+ *  <roms>
+ *    <crom name="foo.bin" offset=0/>
+ *    <crom name="bar.bin" offset=2/>
+ *  </roms>
+ *
+ * config["game/roms"].Value()              <-- should return nothing
+ * config["game/roms/crom/offset"].Value()  <-- "2", the second <crom> tag
+ * config["game/roms"].begin()              <-- iterate over two <crom> tags
+ *
+ * INI Semantics
+ * -------------
+ *
+ * INI files are linear in nature and divided into sections. Config trees built
+ * to represent INI files must adhere to the following rules:
+ *
+ *  - Section nodes have their key set to the section name and value empty.
+ *    They are the only nodes that can have children (i.e., IsLeaf() == false,
+ *    HasChildren() == true).
+ *  - Top-level node in the tree is the global section, and its key is 
+ *    "Global".
+ *  - Only the global section (top-level section) may have child nodes that are
+ *    sections. The config tree can therefore only be up to 2 levels deep: the
+ *    first, top-most level consists of global parameters, and section nodes
+ *    provide one more level of nesting.
+ *
+ * INI files contain zero or more sections followed by zero or more settings
+ * each.
+ *
+ *  Setting0 = 100
+ *  [ Global ]
+ *  Setting1 = 200
+ *  [ Section1 ]
+ *  SettingA = 1      ; this is a comment
+ *  SettingB = foo
+ *  [ Section2 ]
+ *  SettingX = bar
+ *  SettingZ = "baz"  ; quotes are optional and are stripped off during parsing
+ *
+ * Any setting not explicitly part of a section is assigned to the "Global"
+ * section. For example, Setting0 and Setting1 above are both part of "Global".
+ */
+
+#include "Util/NewConfig.h"
+#include "OSD/Logger.h"
+#include <algorithm>
+#include <fstream>
+#include <iostream>
+
+namespace Util
+{
+  namespace Config
+  {
+    Node Node::s_empty_node;
+
+    const Node &Node::operator[](const std::string &path) const
+    {
+      const Node *e = this;
+      std::vector<std::string> keys = Util::Format(path).Split('/');
+      for (auto &key: keys)
+      {
+        auto it = e->m_children.find(key);
+        if (it == e->m_children.end())
+          return s_empty_node;
+        e = it->second.get();
+      }
+      return *e;
+    }
+
+    Node &Node::Get(const std::string &path)
+    {
+      return const_cast<Node &>(operator[](path));
+    }
+
+    const Node &Node::Get(const std::string &path) const
+    {
+      return operator[](path);
+    }
+
+    void Node::Print(size_t indent_level) const
+    {
+      std::fill_n(std::ostream_iterator<char>(std::cout), 2 * indent_level, ' ');
+      std::cout << m_key;
+      if (m_value.length())
+        std::cout << '=' << m_value;
+      std::cout << "  children={";
+      for (auto v: m_children)
+        std::cout << ' ' << v.first;
+      std::cout << " }" << std::endl;
+      for (Ptr_t child = m_first_child; child; child = child->m_next_sibling)
+        child->Print(indent_level + 1);
+    }
+
+    Node &Node::Create(const std::string &key)
+    {
+      Ptr_t node = std::make_shared<Node>(key);
+      AddChild(node);
+      return *node;
+    }
+
+    Node &Node::Create(const std::string &key, const std::string &value)
+    {
+      Ptr_t node = std::make_shared<Node>(key, value);
+      AddChild(node);
+      return *node;
+    }
+
+    // Adds a newly-created node (which, among other things, implies no
+    // children) as a child 
+    void Node::AddChild(Ptr_t &node)
+    {
+      if (!m_last_child)
+      {
+        m_first_child = node;
+        m_last_child = node;
+      }
+      else
+      {
+        m_last_child->m_next_sibling = node;
+        m_last_child = node;
+      }    
+      m_children[node->m_key] = node;
+    }
+
+    /*
+    void Node::Clear()
+    {
+      m_next_sibling.reset();
+      m_first_child.reset();
+      m_last_child.reset();
+      m_children.clear();
+      m_key.clear();
+      m_value.clear();
+    }
+    */
+
+    Node::Node()
+    {
+      //std::cout << "Created " << "<null>" << " (" << this << ")" << std::endl;
+    }
+
+    Node::Node(const std::string &key)
+      : m_key(key)
+    {
+      //std::cout << "Created " << key << " (" << this << ")" << std::endl;
+    }
+
+    Node::Node(const std::string &key, const std::string &value)
+      : m_key(key),
+        m_value(value)
+    {
+      //std::cout << "Created " << key << '=' << value << " (" << this << ")" << std::endl;
+    }
+
+    // Deep copy
+    Node::Node(const Node &that)
+      : m_key(that.m_key),
+        m_value(that.m_value)
+    {
+      for (Ptr_t child = that.m_first_child; child; child = child->m_next_sibling)
+      {
+        Ptr_t copied_child = std::make_shared<Node>(*child);
+        AddChild(copied_child);
+      }
+    }
+
+    Node::~Node()
+    {
+      //std::cout << "Destroyed " << m_key << " (" << this << ")" << std::endl;
+    }
+
+    Node::Ptr_t CreateEmpty()
+    {
+      return std::shared_ptr<Node>(new Node());
+    }
+
+    static std::string StripComment(const std::string &line)
+    {
+      // Find first semicolon not enclosed in ""
+      bool inside_quotes = false;
+      for (auto it = line.begin(); it != line.end(); ++it)
+      {
+        inside_quotes ^= (*it == '\"');
+        if (!inside_quotes && *it == ';')
+          return std::string(line.begin(), it);
+      }
+      return line;
+    }
+
+    static void ParseAssignment(Node &current_section, const std::string &filename, size_t line_num, const std::string &line)
+    {
+      size_t idx_equals = line.find_first_of('=');
+      if (idx_equals == std::string::npos)
+      {
+        //std::cerr << filename << ':' << line_num << ": Syntax error. No '=' found." << std::endl;
+        ErrorLog("%s:%d: Syntax error. No '=' found.", filename.c_str(), line_num);
+        return;
+      }
+      std::string lvalue(TrimWhiteSpace(std::string(line.begin(), line.begin() + idx_equals)));
+      if (lvalue.empty())
+      {
+        //std::cerr << filename << ':' << line_num << ": Syntax error. Setting name missing before '='." << std::endl;
+        ErrorLog("%s:%d: Syntax error. Setting name missing before '='.", filename.c_str(), line_num);
+        return;
+      }
+      // Get rvalue, which is allowed to be empty and strip off quotes if they
+      // exist. Only a single pair of quotes encasing the rvalue are permitted.
+      std::string rvalue(TrimWhiteSpace(std::string(line.begin() + idx_equals + 1, line.end())));
+      size_t idx_first_quote = rvalue.find_first_of('\"');
+      size_t idx_last_quote = rvalue.find_last_of('\"');
+      if (idx_first_quote == 0 && idx_last_quote == (rvalue.length() - 1) && idx_first_quote != idx_last_quote)
+        rvalue = std::string(rvalue.begin() + idx_first_quote + 1, rvalue.begin() + idx_last_quote);
+      if (std::count(rvalue.begin(), rvalue.end(), '\"') != 0)
+      {
+        //std::cerr << filename << ':' << line_num << ": Warning: Extraneous quotes present on line." << std::endl;
+        ErrorLog("%s:%d: Warning: Extraneous quotes present on line.", filename.c_str(), line_num);
+      }
+      // In INI files, we do not allow multiple settings with the same key. If
+      // a setting is specified multiple times, previous ones are overwritten.
+      if (current_section[lvalue].Empty())
+        current_section.Create(lvalue, rvalue);
+      else
+        current_section.Get(lvalue).SetValue(rvalue);
+    }
+          
+    Node::Ptr_t FromINIFile(const std::string &filename)
+    {
+      std::ifstream file;
+      file.open(filename);
+      if (file.fail())
+      {
+        ErrorLog("Unable to open '%s'. Configuration will not be loaded.", filename.c_str());
+        return CreateEmpty();
+      }
+
+      Node::Ptr_t global_ptr = std::make_shared<Node>("Global");  // the root is also the "Global" section
+      Node &global = *global_ptr;
+      Node *current_section = &global;
+
+      size_t line_num = 1;
+      while (!file.eof())
+      {
+        if (file.fail())
+        {
+          ErrorLog("%s:%d: File read error. Configuration will be incomplete.");
+          return CreateEmpty();
+        }
+
+        std::string line;
+        std::getline(file, line);
+        line = StripComment(line);
+        line = TrimWhiteSpace(line);
+
+        if (!line.empty())
+        {
+          if (*line.begin() == '[' && *line.rbegin() == ']')
+          {
+            // Check if section exists else create a new one
+            std::string section(TrimWhiteSpace(std::string(line.begin() + 1, line.begin() + line.length() - 1)));
+            if (section.empty() || section == "Global") // empty section names (e.g., "[]") assigned to "[ Global ]"
+              current_section = &global;
+            else if (global[section].Empty())
+            {
+              Node &new_section = global.Create(section);
+              current_section = &new_section;
+            }
+            else
+              current_section = &global.Get(section);
+          }
+          else
+          {
+            ParseAssignment(*current_section, filename, line_num, line);
+          }
+        }
+
+        line_num++;
+      }
+
+      return global_ptr;
+    }
+    
+    /*
+     * Produces a new INI section by merging two existing sections.
+     *
+     * - Nodes from x and y with children are ignored as per INI semantics.
+     *   The presence of children indicates a section, not a setting.
+     * - Settings from y override settings in x if already present.
+     * - x's key is retained.
+     */
+    Node::Ptr_t MergeINISections(const Node &x, const Node &y)
+    {
+      Node::Ptr_t merged_ptr = std::make_shared<Node>(x.Key()); // result has same key as x
+      Node &merged = *merged_ptr;
+      // First copy settings from section x
+      for (auto it = x.begin(); it != x.end(); ++it)
+      {
+        if (it->IsLeaf())
+          merged.Create(it->Key(), it->Value());
+      }
+      // Merge in settings from section y
+      for (auto it = y.begin(); it != y.end(); ++it)
+      {
+        auto &key = it->Key();
+        auto &value = it->Value();
+        if (it->IsLeaf())
+        {
+          if (merged[key].Empty())
+            merged.Create(key, value);
+          else
+            merged.Get(key).SetValue(value);
+        }
+      }
+      return merged_ptr;
+    }
+
+    static void WriteSection(std::ofstream &file, const Node &section)
+    {
+      file << "[ " << section.Key() << " ]" << std::endl;
+      file << std::endl;
+      for (auto it = section.begin(); it != section.end(); ++it)
+      {
+        if (it->IsLeaf())
+          file << it->Key() << " = \"" << it->Value() << "\"" << std::endl;
+      }
+      file << std::endl << std::endl;
+    }
+
+    void WriteINIFile(const std::string &filename, const Node &config, const std::string &header_comment)
+    {
+      std::ofstream file;
+      file.open(filename);
+      if (file.fail())
+      {
+        ErrorLog("Unable to write to '%s'. Configuration will not be saved.");
+        return;
+      }
+      if (!header_comment.empty())
+        file << header_comment << std::endl << std::endl;
+      WriteSection(file, config);
+      for (auto it = config.begin(); it != config.end(); ++it)
+      {
+        if (it->HasChildren())
+          WriteSection(file, *it);
+      }
+    }
+  } // Config
+} // Util
+

Src/Util/NewConfig.h

@@ -0,0 +1,204 @@
+#ifndef INCLUDED_UTIL_CONFIG_H
+#define INCLUDED_UTIL_CONFIG_H
+
+#include "Util/Format.h"
+#include <map>
+#include <memory>
+#include <iterator>
+
+namespace Util
+{
+  namespace Config
+  {
+    class Node
+    {
+    public:
+      typedef std::shared_ptr<Node> Ptr_t;
+      typedef std::shared_ptr<const Node> ConstPtr_t;
+
+    private:
+      Ptr_t m_next_sibling;
+      Ptr_t m_first_child;
+      Ptr_t m_last_child;
+      std::map<std::string, Ptr_t> m_children;
+      const std::string m_key;
+      std::string m_value;
+      static Node s_empty_node; // key, value, and children must always be empty
+
+      void AddChild(Ptr_t &node);
+      Node();                   // prohibit accidental/unintentional creation of blank nodes
+      friend Ptr_t CreateEmpty();
+
+    public:
+      class const_iterator;
+
+      class iterator: public std::iterator<std::forward_iterator_tag, Node>
+      {
+      private:
+        Ptr_t m_node;
+        friend class const_iterator;    
+      public:
+        inline iterator(Ptr_t node = Ptr_t())
+          : m_node(node)
+        {}
+        inline iterator(const iterator &it)
+          : m_node(it.m_node)
+        {}
+        inline iterator operator++()
+        {
+          // Prefix increment
+          m_node = m_node->m_next_sibling;
+          return *this;
+        }
+        inline iterator operator++(int)
+        {
+          // Postfix increment
+          iterator current(*this);
+          m_node = m_node->m_next_sibling;
+          return *this;
+        }
+        inline Node &operator*() const
+        {
+          return *m_node;
+        }
+        inline Ptr_t operator->() const
+        {
+          return m_node;
+        }
+        inline bool operator==(const iterator &rhs) const
+        {
+          return m_node == rhs.m_node;
+        }
+        inline bool operator!=(const iterator &rhs) const
+        {
+          return m_node != rhs.m_node;
+        }
+      };
+
+      class const_iterator: public std::iterator<std::forward_iterator_tag, const Node>
+      {
+      private:
+        ConstPtr_t m_node;
+      public:
+        inline const_iterator(ConstPtr_t node = ConstPtr_t())
+          : m_node(node)
+        {}
+        inline const_iterator(Ptr_t node = Ptr_t())
+          : m_node(std::const_pointer_cast<const Node>(node))
+        {}
+        inline const_iterator(const const_iterator &it)
+          : m_node(it.m_node)
+        {}
+        inline const_iterator(const Node::iterator &it)
+          : m_node(it.m_node)
+        {}
+        inline const_iterator operator++()
+        {
+          // Prefix increment
+          m_node = m_node->m_next_sibling;
+          return *this;
+        }
+        inline const_iterator operator++(int)
+        {
+          // Postfix increment
+          iterator current(*this);
+          m_node = m_node->m_next_sibling;
+          return *this;
+        }
+        inline const Node &operator*() const
+        {
+          return *m_node;
+        }
+        inline ConstPtr_t operator->() const
+        {
+          return m_node;
+        }
+        inline bool operator==(const const_iterator &rhs) const
+        {
+          return m_node == rhs.m_node;
+        }
+        inline bool operator!=(const const_iterator &rhs) const
+        {
+          return m_node != rhs.m_node;
+        }
+      };
+
+      inline iterator begin()
+      {
+        return iterator(m_first_child);
+      }
+
+      inline iterator end()
+      {
+        return iterator();
+      }
+      
+      inline const_iterator begin() const
+      {
+        return iterator(m_first_child);
+      }
+
+      inline const_iterator end() const
+      {
+        return iterator();
+      }
+
+      const inline std::string &Key() const
+      {
+        return m_key;
+      }
+
+      const inline std::string &ValueWithDefault(const std::string &default_value) const
+      {
+        if (this == &s_empty_node)
+          return default_value;
+        return m_value;
+      }
+
+      const inline std::string &Value() const
+      {
+        //TODO: if empty node, throw exception?
+        return m_value;
+      }
+
+      inline void SetValue(const std::string &value)
+      {
+        if (this != &s_empty_node)  // not allowed to modify empty node
+          m_value = value;
+      }
+
+      inline bool Empty() const
+      {
+        return m_key.empty();
+      }
+
+      inline bool IsLeaf() const
+      {
+        return m_children.empty();
+      }
+
+      inline bool HasChildren() const
+      {
+        return !IsLeaf();
+      }
+
+      Node &Get(const std::string &path);
+      const Node &operator[](const std::string &path) const;
+      const Node &Get(const std::string &path) const;
+      void Print(size_t indent_level = 0) const;
+      Node &Create(const std::string &key);
+      Node &Create(const std::string &key, const std::string &value);
+      Node(const std::string &key);
+      Node(const std::string &key, const std::string &value);
+      Node(const Node &that);
+      ~Node();
+    };
+    
+    Node::Ptr_t CreateEmpty();
+    Node::Ptr_t FromINIFile(const std::string &filename);
+    Node::Ptr_t MergeINISections(const Node &x, const Node &y);
+    void WriteINIFile(const std::string &filename, const Node &config, const std::string &header_comment);
+  } // Config
+} // Util
+
+#endif // INCLUDED_UTIL_CONFIG_H

Src/Util/Test_Config.cpp

@@ -0,0 +1,61 @@
+#include "Util/NewConfig.h"
+#include <iostream>
+
+int main()
+{
+  /*
+   * Creates a config tree corresponding to the following:
+   *
+   *  <game>
+   *    <name>scud</name>
+   *    <roms>
+   *      <crom>
+   *        <name>foo.bin</name>
+   *        <offset>0</offset>
+   *      </crom>
+   *      <crom>
+   *        <name>bar.bin</name>
+   *        <offset>2</offset>
+   *      </crom>
+   *    </roms>
+   *  </game>
+   */
+  Util::Config::Node::Ptr_t root = std::make_shared<Util::Config::Node>("global");
+  auto &game = root->Create("game");
+  game.Create("name", "scud");
+  auto &roms = game.Create("roms");
+  auto &crom1 = roms.Create("crom");
+  crom1.Create("name", "foo.bin");
+  crom1.Create("offset", "0");
+  auto &crom2 = roms.Create("crom");
+  crom2.Create("name", "bar.bin");
+  crom2.Create("offset", "2");
+  
+  const char *expected_output =
+    "global  children={ game }              \n"
+    "  game  children={ name roms }         \n"
+    "    name=scud  children={ }            \n"
+    "    roms  children={ crom }            \n"
+    "      crom  children={ name offset }   \n"
+    "        name=foo.bin  children={ }     \n"
+    "        offset=0  children={ }         \n"
+    "      crom  children={ name offset }   \n"
+    "        name=bar.bin  children={ }     \n"
+    "        offset=2  children={ }         \n";
+  std::cout << "Expected output:" << std::endl << std::endl << expected_output << std::endl;
+  std::cout << "Actual config tree:" << std::endl << std::endl;
+  root->Print();
+  std::cout << std::endl;
+
+  // Expect second crom: bar.bin
+  auto &global = *root;
+  std::cout << "game/roms/crom/name=" << global["game/roms/crom/name"].Value() << " (expected: bar.bin)" << std::endl << std::endl;
+    
+  // Make a copy
+  std::cout << "Copy:" << std::endl << std::endl;
+  Util::Config::Node::Ptr_t copy = std::make_shared<Util::Config::Node>(*root);
+  copy->Print();
+  std::cout << std::endl;
+  return 0;
+}
+