/*

** $Id: llimits.h,v 1.52 2003/02/20 19:33:23 roberto Exp $

** Limits, basic types, and some other `installation-dependent' definitions

** See Copyright Notice in lua.h

*/



#ifndef llimits_h

#define llimits_h





#include <limits.h>

#include <stddef.h>





#include "lua.h"





/*

** try to find number of bits in an integer

*/

#ifndef BITS_INT

/* avoid overflows in comparison */

#if INT_MAX-20 < 32760

#define	BITS_INT	16

#else

#if INT_MAX > 2147483640L

/* machine has at least 32 bits */

#define BITS_INT	32

#else

#error "you must define BITS_INT with number of bits in an integer"

#endif

#endif

#endif





/*

** the following types define integer types for values that may not

** fit in a `small int' (16 bits), but may waste space in a

** `large long' (64 bits). The current definitions should work in

** any machine, but may not be optimal.

*/



/* an unsigned integer to hold hash values */

typedef unsigned int lu_hash;

/* its signed equivalent */

typedef int ls_hash;



/* an unsigned integer big enough to count the total memory used by Lua; */

/* it should be at least as large as size_t */

typedef unsigned long lu_mem;



#define MAX_LUMEM	ULONG_MAX





/* an integer big enough to count the number of strings in use */

typedef long ls_nstr;



/* chars used as small naturals (so that `char' is reserved for characters) */

typedef unsigned char lu_byte;





#define MAX_SIZET	((size_t)(~(size_t)0)-2)





#define MAX_INT (INT_MAX-2)  /* maximum value of an int (-2 for safety) */



/*

** conversion of pointer to integer

** this is for hashing only; there is no problem if the integer

** cannot hold the whole pointer value

*/

#define IntPoint(p)  ((lu_hash)(p))







/* type to ensure maximum alignment */

#ifndef LUSER_ALIGNMENT_T

typedef union { double u; void *s; long l; } L_Umaxalign;

#else

typedef LUSER_ALIGNMENT_T L_Umaxalign;

#endif





/* result of `usual argument conversion' over lua_Number */

#ifndef LUA_UACNUMBER

typedef double l_uacNumber;

#else

typedef LUA_UACNUMBER l_uacNumber;

#endif





#ifndef lua_assert

#define lua_assert(c)		/* empty */

#endif





#ifndef check_exp

#define check_exp(c,e)	(e)

#endif





#ifndef UNUSED

#define UNUSED(x)	((void)(x))	/* to avoid warnings */

#endif





#ifndef cast

#define cast(t, exp)	((t)(exp))

#endif







/*

** type for virtual-machine instructions

** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)

*/

typedef unsigned long Instruction;





/* maximum depth for calls (unsigned short) */

#ifndef LUA_MAXCALLS

#define LUA_MAXCALLS        4096

#endif





/*

** maximum depth for C calls (unsigned short): Not too big, or may

** overflow the C stack...

*/



#ifndef LUA_MAXCCALLS

#define LUA_MAXCCALLS        200

#endif





/* maximum size for the C stack */

#ifndef LUA_MAXCSTACK

#define LUA_MAXCSTACK        2048

#endif





/* maximum stack for a Lua function */

#define MAXSTACK	250





/* maximum number of variables declared in a function */

#ifndef MAXVARS

#define MAXVARS 200           /* arbitrary limit (<MAXSTACK) */

#endif





/* maximum number of upvalues per function */

#ifndef MAXUPVALUES

#define MAXUPVALUES	32

#endif





/* maximum number of parameters in a function */

#ifndef MAXPARAMS

#define MAXPARAMS 100           /* arbitrary limit (<MAXLOCALS) */

#endif





/* minimum size for the string table (must be power of 2) */

#ifndef MINSTRTABSIZE

#define MINSTRTABSIZE	32

#endif





/* minimum size for string buffer */

#ifndef LUA_MINBUFFER

#define LUA_MINBUFFER	32

#endif





/*

** maximum number of syntactical nested non-terminals: Not too big,

** or may overflow the C stack...

*/

#ifndef LUA_MAXPARSERLEVEL

#define LUA_MAXPARSERLEVEL	200

#endif





#endif

