/*
** $Id: lfunc.h,v 2.15 2015/01/13 15:49:11 roberto Exp $
** Auxiliary functions to manipulate prototypes and closures
** See Copyright Notice in lua.h
*/

#ifndef lfunc_h
#define lfunc_h


#include "lobject.h"


#define sizeCclosure(n)	(cast(int, sizeof(CClosure)) + \
                         cast(int, sizeof(TValue)*((n)-1)))

#define sizeLclosure(n)	(cast(int, sizeof(LClosure)) + \
                         cast(int, sizeof(TValue *)*((n)-1)))


/* test whether thread is in 'twups' list */
#define isintwups(L)	(L->twups != L)


/*
** maximum number of upvalues in a closure (both C and Lua). (Value
** must fit in a VM register.)
*/
#define MAXUPVAL	255


/*
** Upvalues for Lua closures
*/
struct UpVal
{
	TValue* v; /* points to stack or to its own value */
	lu_mem refcount; /* reference counter */
	union
	{
		struct
		{
			/* (when open) */
			UpVal* next; /* linked list */
			int touched; /* mark to avoid cycles with dead threads */
		} open;

		TValue value; /* the value (when closed) */
	} u;
};

#define upisopen(up)	((up)->v != &(up)->u.value)


LUAI_FUNC Proto* luaF_newproto(lua_State* L);
LUAI_FUNC CClosure* luaF_newCclosure(lua_State* L, int nelems);
LUAI_FUNC LClosure* luaF_newLclosure(lua_State* L, int nelems);
LUAI_FUNC void luaF_initupvals(lua_State* L, LClosure* cl);
LUAI_FUNC UpVal* luaF_findupval(lua_State* L, StkId level);
LUAI_FUNC void luaF_close(lua_State* L, StkId level);
LUAI_FUNC void luaF_freeproto(lua_State* L, Proto* f);
LUAI_FUNC const char* luaF_getlocalname(const Proto* func, int local_number,
                                        int pc);


#endif