/*** $Id: llimits.h,v 1.99 2012/05/28 20:32:28 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"  typedef unsigned LUA_INT32 lu_int32; typedef LUAI_UMEM lu_mem; typedef LUAI_MEM l_mem;   /* 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_LUMEM	((lu_mem)(~(lu_mem)0)-2) #define MAX_LMEM	((l_mem) ((MAX_LUMEM >> 1) - 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)  ((unsigned int)(lu_mem)(p))   /* type to ensure maximum alignment */#if !defined(LUAI_USER_ALIGNMENT_T)#define LUAI_USER_ALIGNMENT_T	union { double u; void *s; long l; }#endif typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;  /* result of a `usual argument conversion' over lua_Number */typedef LUAI_UACNUMBER l_uacNumber;  /* internal assertions for in-house debugging */#if defined(lua_assert)#define check_exp(c,e)		(lua_assert(c), (e))/* to avoid problems with conditions too long */#define lua_longassert(c)	{ if (!(c)) lua_assert(0); }#else#define lua_assert(c)		((void)0)#define check_exp(c,e)		(e)#define lua_longassert(c)	((void)0)#endif /*** assertion for checking API calls*/#if !defined(luai_apicheck) #if defined(LUA_USE_APICHECK)#include <assert.h>#define luai_apicheck(L,e)	assert(e)#else#define luai_apicheck(L,e)	lua_assert(e)#endif #endif #define api_check(l,e,msg)	luai_apicheck(l,(e) && msg)  #if !defined(UNUSED)#define UNUSED(x)	((void)(x))	/* to avoid warnings */#endif  #define cast(t, exp)	((t)(exp)) #define cast_byte(i)	cast(lu_byte, (i))#define cast_num(i)	cast(lua_Number, (i))#define cast_int(i)	cast(int, (i))#define cast_uchar(i)	cast(unsigned char, (i))  /*** non-return type*/#if defined(__GNUC__)#define l_noret		void __attribute__((noreturn))#elif defined(_MSC_VER)#define l_noret		void __declspec(noreturn)#else#define l_noret		void#endif   /*** maximum depth for nested C calls and syntactical nested non-terminals** in a program. (Value must fit in an unsigned short int.)*/#if !defined(LUAI_MAXCCALLS)#define LUAI_MAXCCALLS		200#endif /*** maximum number of upvalues in a closure (both C and Lua). (Value** must fit in an unsigned char.)*/#define MAXUPVAL	UCHAR_MAX  /*** type for virtual-machine instructions** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)*/typedef lu_int32 Instruction;   /* maximum stack for a Lua function */#define MAXSTACK	250   /* minimum size for the string table (must be power of 2) */#if !defined(MINSTRTABSIZE)#define MINSTRTABSIZE	32#endif  /* minimum size for string buffer */#if !defined(LUA_MINBUFFER)#define LUA_MINBUFFER	32#endif  #if !defined(lua_lock)#define lua_lock(L)     ((void) 0)#define lua_unlock(L)   ((void) 0)#endif #if !defined(luai_threadyield)#define luai_threadyield(L)     {lua_unlock(L); lua_lock(L);}#endif  /*** these macros allow user-specific actions on threads when you defined** LUAI_EXTRASPACE and need to do something extra when a thread is** created/deleted/resumed/yielded.*/#if !defined(luai_userstateopen)#define luai_userstateopen(L)		((void)L)#endif #if !defined(luai_userstateclose)#define luai_userstateclose(L)		((void)L)#endif #if !defined(luai_userstatethread)#define luai_userstatethread(L,L1)	((void)L)#endif #if !defined(luai_userstatefree)#define luai_userstatefree(L,L1)	((void)L)#endif #if !defined(luai_userstateresume)#define luai_userstateresume(L,n)       ((void)L)#endif #if !defined(luai_userstateyield)#define luai_userstateyield(L,n)        ((void)L)#endif /*** lua_number2int is a macro to convert lua_Number to int.** lua_number2integer is a macro to convert lua_Number to lua_Integer.** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned.** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number.** luai_hashnum is a macro to hash a lua_Number value into an integer.** The hash must be deterministic and give reasonable values for** both small and large values (outside the range of integers).*/ #if defined(MS_ASMTRICK)	/* { *//* trick with Microsoft assembler for X86 */ #define lua_number2int(i,n)  __asm {__asm fld n   __asm fistp i}#define lua_number2integer(i,n)		lua_number2int(i, n)#define lua_number2unsigned(i,n)  \  {__int64 l; __asm {__asm fld n   __asm fistp l} i = (unsigned int)l;}  #elif defined(LUA_IEEE754TRICK)		/* }{ *//* the next trick should work on any machine using IEEE754 with   a 32-bit int type */ union luai_Cast { double l_d; LUA_INT32 l_p[2]; }; #if !defined(LUA_IEEEENDIAN)	/* { */#define LUAI_EXTRAIEEE	\  static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};#define LUA_IEEEENDIANLOC	(ieeeendian.l_p[1] == 33)#else#define LUA_IEEEENDIANLOC	LUA_IEEEENDIAN#define LUAI_EXTRAIEEE		/* empty */#endif				/* } */ #define lua_number2int32(i,n,t) \  { LUAI_EXTRAIEEE \    volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \    (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; } #define luai_hashnum(i,n)  \  { volatile union luai_Cast u; u.l_d = (n) + 1.0;  /* avoid -0 */ \    (i) = u.l_p[0]; (i) += u.l_p[1]; }  /* add double bits for his hash */ #define lua_number2int(i,n)		lua_number2int32(i, n, int)#define lua_number2unsigned(i,n)	lua_number2int32(i, n, lua_Unsigned) /* the trick can be expanded to lua_Integer when it is a 32-bit value */#if defined(LUA_IEEELL)#define lua_number2integer(i,n)		lua_number2int32(i, n, lua_Integer)#endif #endif				/* } */  /* the following definitions always work, but may be slow */ #if !defined(lua_number2int)#define lua_number2int(i,n)	((i)=(int)(n))#endif #if !defined(lua_number2integer)#define lua_number2integer(i,n)	((i)=(lua_Integer)(n))#endif #if !defined(lua_number2unsigned)	/* { *//* the following definition assures proper modulo behavior */#if defined(LUA_NUMBER_DOUBLE)#include <math.h>#define SUPUNSIGNED	((lua_Number)(~(lua_Unsigned)0) + 1)#define lua_number2unsigned(i,n)  \	((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))#else#define lua_number2unsigned(i,n)	((i)=(lua_Unsigned)(n))#endif#endif				/* } */  #if !defined(lua_unsigned2number)/* on several machines, coercion from unsigned to double is slow,   so it may be worth to avoid */#define lua_unsigned2number(u)  \    (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))#endif   #if defined(ltable_c) && !defined(luai_hashnum) #include <float.h>#include <math.h> #define luai_hashnum(i,n) { int e;  \  n = frexp(n, &e) * (lua_Number)(INT_MAX - DBL_MAX_EXP);  \  lua_number2int(i, n); i += e; } #endif   /*** macro to control inclusion of some hard tests on stack reallocation*/#if !defined(HARDSTACKTESTS)#define condmovestack(L)	((void)0)#else/* realloc stack keeping its size */#define condmovestack(L)	luaD_reallocstack((L), (L)->stacksize)#endif #if !defined(HARDMEMTESTS)#define condchangemem(L)	condmovestack(L)#else#define condchangemem(L)  \	((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1)))#endif #endif