add key renaming

fix a possible glitch

stepmania/src/IniFile.cpp

@@ -246,7 +246,20 @@ bool IniFile::DeleteKey(const CString &keyname)
 	return true;
 }
 
-IniFile::const_iterator IniFile::GetKey(const CString &keyname) const
+const IniFile::key *IniFile::GetKey(const CString &keyname) const
 {
-	return keys.find(keyname);
+	keymap::const_iterator i = keys.find(keyname);
+	if(i == keys.end()) return NULL;
+	return &i->second;
+}
+
+void IniFile::RenameKey(const CString &from, const CString &to)
+{
+	if(keys.find(from) == keys.end())
+		return;
+	if(keys.find(to) != keys.end())
+		return;
+
+	keys[to] = keys[from];
+	keys.erase(from);
 }

stepmania/src/IniFile.h

@@ -90,7 +90,12 @@ public:
 	//returns true if key existed and deleted, false otherwise
 	bool DeleteKey(const CString &keyname);
 
-	const_iterator GetKey(const CString &keyname) const;
+	const key *GetKey(const CString &keyname) const;
+
+	/* Rename a key. For example, call RenameKey("foo", "main") after
+	 * reading an INI where [foo] is an alias to [main].  If to already
+	 * exists, nothing happens. */
+	void RenameKey(const CString &from, const CString &to);
 };
 
 #endif

stepmania/src/InputMapper.cpp

@@ -75,12 +75,12 @@ void InputMapper::ReadMappingsFromDisk()
 	if( !ini.ReadFile() )
 		LOG->Warn( "could not input mapping file '%s'.", sPath.GetString() );
 
-	IniFile::const_iterator Key = ini.GetKey( "Input" );
+	const IniFile::key *Key = ini.GetKey( "Input" );
 
-	if( Key != ini.end() )
+	if( Key  )
 	{
-		for( IniFile::key::const_iterator i = Key->second.begin(); 
-			i != Key->second.end(); ++i )
+		for( IniFile::key::const_iterator i = Key->begin(); 
+			i != Key->end(); ++i )
 		{
 			CString name = i->first;
 			CString value = i->second;

stepmania/src/SongManager.cpp

@@ -265,11 +265,11 @@ void SongManager::ReadStatisticsFromDisk()
 
 
 	// load song statistics
-	IniFile::const_iterator Key = ini.GetKey( "Statistics" );
-	if( Key != ini.end() )
+	const IniFile::key *Key = ini.GetKey( "Statistics" );
+	if( Key )
 	{
-		for( IniFile::key::const_iterator i = Key->second.begin(); 
-			i != Key->second.end(); ++i )
+		for( IniFile::key::const_iterator i = Key->begin(); 
+			i != Key->end(); ++i )
 		{
 			CString name = i->first;
 			CString value = i->second;