add Lua hooks

stepmania/src/SongManager.cpp

@@ -946,3 +946,50 @@ void SongManager::FreeAllLoadedFromProfiles()
 	}
 }
 
+static bool CheckPointer( const Song *p )
+{
+	const vector<Song*> &songs = SONGMAN->GetAllSongs();
+	for( unsigned i = 0; i < songs.size(); ++i )
+		if( songs[i] == p )
+			return true;
+	return false;
+}
+
+
+#include "LuaFunctions.h"
+#define LuaFunction_Song( func, call ) \
+int LuaFunc_##func( lua_State *L ) { \
+	REQ_ARGS( #func, 1 ); \
+	REQ_ARG( #func, 1, lightuserdata ); \
+	const Song *p = (const Song *) (lua_touserdata( L, -1 )); \
+	LUA_ASSERT( CheckPointer(p), ssprintf("%p is not a valid song", p) ); \
+	LUA_RETURN( call ); \
+} \
+LuaFunction( func ); /* register it */
+
+LuaFunction_Str( Song, SONGMAN->FindSong( str ) );
+
+LuaFunction_Song( SongFullDisplayTitle, p->GetFullDisplayTitle() );
+
+static bool CheckPointer( const Steps *p )
+{
+	const vector<Song*> &songs = SONGMAN->GetAllSongs();
+	for( unsigned i = 0; i < songs.size(); ++i )
+	{
+		for( unsigned j = 0; j < songs.size(); ++j )
+			if( songs[i]->m_apNotes[j] == p )
+				return true;
+	}
+	return false;
+}
+
+#define LuaFunction_Steps( func, call ) \
+int LuaFunc_##func( lua_State *L ) { \
+	REQ_ARGS( #func, 1 ); \
+	REQ_ARG( #func, 1, lightuserdata ); \
+	const Steps *p = (const Steps *) (lua_touserdata( L, -1 )); \
+	LUA_ASSERT( CheckPointer(p), ssprintf("%p is not a valid steps", p) ); \
+	LUA_RETURN( call ); \
+} \
+LuaFunction( func ); /* register it */
+LuaFunction_Steps( StepsMeter, p->GetMeter() );