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** $Id: llimits.h,v 1.103 2013/02/20 14:08:56 roberto Exp $
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** Limits, basic types, and some other `installation-dependent' definitions
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** See Copyright Notice in lua.h
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typedef unsigned LUA_INT32 lu_int32;
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typedef LUAI_UMEM lu_mem;
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typedef LUAI_MEM l_mem;
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/* chars used as small naturals (so that `char' is reserved for characters) */
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typedef unsigned char lu_byte;
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#define MAX_SIZET ((size_t)(~(size_t)0)-2)
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#define MAX_LUMEM ((lu_mem)(~(lu_mem)0)-2)
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#define MAX_LMEM ((l_mem) ((MAX_LUMEM >> 1) - 2))
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#define MAX_INT (INT_MAX-2) /* maximum value of an int (-2 for safety) */
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** conversion of pointer to integer
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** this is for hashing only; there is no problem if the integer
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** cannot hold the whole pointer value
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#define IntPoint(p) ((unsigned int)(lu_mem)(p))
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/* type to ensure maximum alignment */
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#if !defined(LUAI_USER_ALIGNMENT_T)
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#define LUAI_USER_ALIGNMENT_T union { double u; void *s; long l; }
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typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;
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/* result of a `usual argument conversion' over lua_Number */
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typedef LUAI_UACNUMBER l_uacNumber;
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/* internal assertions for in-house debugging */
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#if defined(lua_assert)
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#define check_exp(c,e) (lua_assert(c), (e))
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/* to avoid problems with conditions too long */
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#define lua_longassert(c) { if (!(c)) lua_assert(0); }
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#define lua_assert(c) ((void)0)
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#define check_exp(c,e) (e)
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#define lua_longassert(c) ((void)0)
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** assertion for checking API calls
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#if !defined(luai_apicheck)
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#if defined(LUA_USE_APICHECK)
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#define luai_apicheck(L,e) assert(e)
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#define luai_apicheck(L,e) lua_assert(e)
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#define api_check(l,e,msg) luai_apicheck(l,(e) && msg)
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#define UNUSED(x) ((void)(x)) /* to avoid warnings */
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#define cast(t, exp) ((t)(exp))
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#define cast_byte(i) cast(lu_byte, (i))
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#define cast_num(i) cast(lua_Number, (i))
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#define cast_int(i) cast(int, (i))
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#define cast_uchar(i) cast(unsigned char, (i))
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#if defined(__GNUC__)
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#define l_noret void __attribute__((noreturn))
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#elif defined(_MSC_VER)
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#define l_noret void __declspec(noreturn)
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** maximum depth for nested C calls and syntactical nested non-terminals
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** in a program. (Value must fit in an unsigned short int.)
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#if !defined(LUAI_MAXCCALLS)
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#define LUAI_MAXCCALLS 200
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** maximum number of upvalues in a closure (both C and Lua). (Value
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** must fit in an unsigned char.)
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#define MAXUPVAL UCHAR_MAX
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** type for virtual-machine instructions
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** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
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typedef lu_int32 Instruction;
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/* maximum stack for a Lua function */
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/* minimum size for the string table (must be power of 2) */
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#if !defined(MINSTRTABSIZE)
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#define MINSTRTABSIZE 32
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/* minimum size for string buffer */
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#if !defined(LUA_MINBUFFER)
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#define LUA_MINBUFFER 32
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#if !defined(lua_lock)
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#define lua_lock(L) ((void) 0)
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#define lua_unlock(L) ((void) 0)
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#if !defined(luai_threadyield)
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#define luai_threadyield(L) {lua_unlock(L); lua_lock(L);}
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** these macros allow user-specific actions on threads when you defined
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** LUAI_EXTRASPACE and need to do something extra when a thread is
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** created/deleted/resumed/yielded.
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#if !defined(luai_userstateopen)
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#define luai_userstateopen(L) ((void)L)
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#if !defined(luai_userstateclose)
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#define luai_userstateclose(L) ((void)L)
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#if !defined(luai_userstatethread)
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#define luai_userstatethread(L,L1) ((void)L)
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#if !defined(luai_userstatefree)
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#define luai_userstatefree(L,L1) ((void)L)
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#if !defined(luai_userstateresume)
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#define luai_userstateresume(L,n) ((void)L)
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#if !defined(luai_userstateyield)
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#define luai_userstateyield(L,n) ((void)L)
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** lua_number2int is a macro to convert lua_Number to int.
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** lua_number2integer is a macro to convert lua_Number to lua_Integer.
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** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned.
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** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number.
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** luai_hashnum is a macro to hash a lua_Number value into an integer.
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** The hash must be deterministic and give reasonable values for
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** both small and large values (outside the range of integers).
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#if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK) /* { */
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/* trick with Microsoft assembler for X86 */
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#define lua_number2int(i,n) __asm {__asm fld n __asm fistp i}
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#define lua_number2integer(i,n) lua_number2int(i, n)
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#define lua_number2unsigned(i,n) \
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{__int64 l; __asm {__asm fld n __asm fistp l} i = (unsigned int)l;}
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#elif defined(LUA_IEEE754TRICK) /* }{ */
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/* the next trick should work on any machine using IEEE754 with
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union luai_Cast { double l_d; LUA_INT32 l_p[2]; };
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#if !defined(LUA_IEEEENDIAN) /* { */
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#define LUAI_EXTRAIEEE \
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static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};
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#define LUA_IEEEENDIANLOC (ieeeendian.l_p[1] == 33)
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#define LUA_IEEEENDIANLOC LUA_IEEEENDIAN
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#define LUAI_EXTRAIEEE /* empty */
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#define lua_number2int32(i,n,t) \
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volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \
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(i) = (t)u.l_p[LUA_IEEEENDIANLOC]; }
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#define luai_hashnum(i,n) \
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{ volatile union luai_Cast u; u.l_d = (n) + 1.0; /* avoid -0 */ \
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(i) = u.l_p[0]; (i) += u.l_p[1]; } /* add double bits for his hash */
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#define lua_number2int(i,n) lua_number2int32(i, n, int)
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#define lua_number2unsigned(i,n) lua_number2int32(i, n, lua_Unsigned)
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/* the trick can be expanded to lua_Integer when it is a 32-bit value */
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#if defined(LUA_IEEELL)
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#define lua_number2integer(i,n) lua_number2int32(i, n, lua_Integer)
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/* the following definitions always work, but may be slow */
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#if !defined(lua_number2int)
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#define lua_number2int(i,n) ((i)=(int)(n))
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#if !defined(lua_number2integer)
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#define lua_number2integer(i,n) ((i)=(lua_Integer)(n))
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#if !defined(lua_number2unsigned) /* { */
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/* the following definition assures proper modulo behavior */
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#if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT)
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#define SUPUNSIGNED ((lua_Number)(~(lua_Unsigned)0) + 1)
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#define lua_number2unsigned(i,n) \
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((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))
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#define lua_number2unsigned(i,n) ((i)=(lua_Unsigned)(n))
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#if !defined(lua_unsigned2number)
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/* on several machines, coercion from unsigned to double is slow,
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so it may be worth to avoid */
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#define lua_unsigned2number(u) \
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(((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))
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#if defined(ltable_c) && !defined(luai_hashnum)
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#define luai_hashnum(i,n) { int e; \
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n = l_mathop(frexp)(n, &e) * (lua_Number)(INT_MAX - DBL_MAX_EXP); \
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lua_number2int(i, n); i += e; }
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** macro to control inclusion of some hard tests on stack reallocation
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#if !defined(HARDSTACKTESTS)
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#define condmovestack(L) ((void)0)
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/* realloc stack keeping its size */
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#define condmovestack(L) luaD_reallocstack((L), (L)->stacksize)
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#if !defined(HARDMEMTESTS)
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#define condchangemem(L) condmovestack(L)
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#define condchangemem(L) \
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((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1)))