/* tolua: funcitons to convert to C types** Support code for Lua bindings.** Written by Waldemar Celes** TeCGraf/PUC-Rio** Apr 2003** $Id: $*//* This code is free software; you can redistribute it and/or modify it.** The software provided hereunder is on an "as is" basis, and** the author has no obligation to provide maintenance, support, updates,** enhancements, or modifications.*/#include "tolua++.h"#include <string.h>#include <stdlib.h>TOLUA_API double tolua_tonumber (lua_State* L, int narg, double def){ return lua_gettop(L)<abs(narg) ? def : lua_tonumber(L,narg);}TOLUA_API const char* tolua_tostring (lua_State* L, int narg, const char* def){ return lua_gettop(L)<abs(narg) ? def : lua_tostring(L,narg);}TOLUA_API void* tolua_touserdata (lua_State* L, int narg, void* def){		/* return lua_gettop(L)<abs(narg) ? def : lua_touserdata(L,narg); */	if (lua_gettop(L)<abs(narg)) { 		return def;	};	 	if (lua_islightuserdata(L, narg)) {			return lua_touserdata(L,narg);	};		return tolua_tousertype(L, narg, def);}extern int push_table_instance(lua_State* L, int lo);TOLUA_API void* tolua_tousertype (lua_State* L, int narg, void* def){ if (lua_gettop(L)<abs(narg))  return def; else {  void* u;  if (!lua_isuserdata(L, narg)) {	  if (!push_table_instance(L, narg)) return NULL;  };  u = lua_touserdata(L,narg);  return (u==NULL) ? NULL : *((void**)u); /* nil represents NULL */ }}TOLUA_API int tolua_tovalue (lua_State* L, int narg, int def){ return lua_gettop(L)<abs(narg) ? def : narg;}TOLUA_API int tolua_toboolean (lua_State* L, int narg, int def){ return lua_gettop(L)<abs(narg) ?  def : lua_toboolean(L,narg);}TOLUA_API double tolua_tofieldnumber (lua_State* L, int lo, int index, double def){ double v; lua_pushnumber(L,index); lua_gettable(L,lo); v = lua_isnil(L,-1) ? def : lua_tonumber(L,-1); lua_pop(L,1); return v;}TOLUA_API const char* tolua_tofieldstring(lua_State* L, int lo, int index, const char* def){ const char* v; lua_pushnumber(L,index); lua_gettable(L,lo); v = lua_isnil(L,-1) ? def : lua_tostring(L,-1); lua_pop(L,1); return v;}TOLUA_API void* tolua_tofielduserdata (lua_State* L, int lo, int index, void* def){ void* v; lua_pushnumber(L,index); lua_gettable(L,lo); v = lua_isnil(L,-1) ? def : lua_touserdata(L,-1); lua_pop(L,1); return v;}TOLUA_API void* tolua_tofieldusertype (lua_State* L, int lo, int index, void* def){ void* v; lua_pushnumber(L,index); lua_gettable(L,lo); v = lua_isnil(L,-1) ? def : (*(void **)(lua_touserdata(L, -1))); /* lua_unboxpointer(L,-1); */ lua_pop(L,1); return v;}TOLUA_API int tolua_tofieldvalue (lua_State* L, int lo, int index, int def){ int v; lua_pushnumber(L,index); lua_gettable(L,lo); v = lua_isnil(L,-1) ? def : lo; lua_pop(L,1); return v;}TOLUA_API int tolua_getfieldboolean (lua_State* L, int lo, int index, int def){ int v; lua_pushnumber(L,index); lua_gettable(L,lo); v = lua_isnil(L,-1) ? 0 : lua_toboolean(L,-1); lua_pop(L,1); return v;}