- /* 
- ** $Id: llimits.h $ 
- ** 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" 
-   
-   
- /* 
- ** 'lu_mem' and 'l_mem' are unsigned/signed integers big enough to count 
- ** the total memory used by Lua (in bytes). Usually, 'size_t' and 
- ** 'ptrdiff_t' should work, but we use 'long' for 16-bit machines. 
- */ 
- #if defined(LUAI_MEM)           /* { external definitions? */ 
- typedef LUAI_UMEM lu_mem; 
- typedef LUAI_MEM l_mem; 
- #elif LUAI_IS32INT      /* }{ */ 
- typedef size_t lu_mem; 
- typedef ptrdiff_t l_mem; 
- #else  /* 16-bit ints */        /* }{ */ 
- typedef unsigned long lu_mem; 
- typedef long l_mem; 
- #endif                          /* } */ 
-   
-   
- /* chars used as small naturals (so that 'char' is reserved for characters) */ 
- typedef unsigned char lu_byte; 
- typedef signed char ls_byte; 
-   
-   
- /* maximum value for size_t */ 
- #define MAX_SIZET       ((size_t)(~(size_t)0)) 
-   
- /* maximum size visible for Lua (must be representable in a lua_Integer) */ 
- #define MAX_SIZE        (sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \ 
-                           : (size_t)(LUA_MAXINTEGER)) 
-   
-   
- #define MAX_LUMEM       ((lu_mem)(~(lu_mem)0)) 
-   
- #define MAX_LMEM        ((l_mem)(MAX_LUMEM >> 1)) 
-   
-   
- #define MAX_INT         INT_MAX  /* maximum value of an int */ 
-   
-   
- /* 
- ** floor of the log2 of the maximum signed value for integral type 't'. 
- ** (That is, maximum 'n' such that '2^n' fits in the given signed type.) 
- */ 
- #define log2maxs(t)     (sizeof(t) * 8 - 2) 
-   
-   
- /* 
- ** test whether an unsigned value is a power of 2 (or zero) 
- */ 
- #define ispow2(x)       (((x) & ((x) - 1)) == 0) 
-   
-   
- /* number of chars of a literal string without the ending \0 */ 
- #define LL(x)   (sizeof(x)/sizeof(char) - 1) 
-   
-   
- /* 
- ** conversion of pointer to unsigned integer: 
- ** this is for hashing only; there is no problem if the integer 
- ** cannot hold the whole pointer value 
- */ 
- #define point2uint(p)   ((unsigned int)((size_t)(p) & UINT_MAX)) 
-   
-   
-   
- /* types of 'usual argument conversions' for lua_Number and lua_Integer */ 
- typedef LUAI_UACNUMBER l_uacNumber; 
- typedef LUAI_UACINT l_uacInt; 
-   
-   
- /* 
- ** Internal assertions for in-house debugging 
- */ 
- #if defined LUAI_ASSERT 
- #undef NDEBUG 
- #include <assert.h> 
- #define lua_assert(c)           assert(c) 
- #endif 
-   
- #if defined(lua_assert) 
- #define check_exp(c,e)          (lua_assert(c), (e)) 
- /* to avoid problems with conditions too long */ 
- #define lua_longassert(c)       ((c) ? (void)0 : 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) 
- #define luai_apicheck(l,e)      ((void)l, lua_assert(e)) 
- #endif 
-   
- #define api_check(l,e,msg)      luai_apicheck(l,(e) && msg) 
-   
-   
- /* macro to avoid warnings about unused variables */ 
- #if !defined(UNUSED) 
- #define UNUSED(x)       ((void)(x)) 
- #endif 
-   
-   
- /* type casts (a macro highlights casts in the code) */ 
- #define cast(t, exp)    ((t)(exp)) 
-   
- #define cast_void(i)    cast(void, (i)) 
- #define cast_voidp(i)   cast(void *, (i)) 
- #define cast_num(i)     cast(lua_Number, (i)) 
- #define cast_int(i)     cast(int, (i)) 
- #define cast_uint(i)    cast(unsigned int, (i)) 
- #define cast_byte(i)    cast(lu_byte, (i)) 
- #define cast_uchar(i)   cast(unsigned char, (i)) 
- #define cast_char(i)    cast(char, (i)) 
- #define cast_charp(i)   cast(char *, (i)) 
- #define cast_sizet(i)   cast(size_t, (i)) 
-   
-   
- /* cast a signed lua_Integer to lua_Unsigned */ 
- #if !defined(l_castS2U) 
- #define l_castS2U(i)    ((lua_Unsigned)(i)) 
- #endif 
-   
- /* 
- ** cast a lua_Unsigned to a signed lua_Integer; this cast is 
- ** not strict ISO C, but two-complement architectures should 
- ** work fine. 
- */ 
- #if !defined(l_castU2S) 
- #define l_castU2S(i)    ((lua_Integer)(i)) 
- #endif 
-   
-   
- /* 
- ** non-return type 
- */ 
- #if !defined(l_noret) 
-   
- #if defined(__GNUC__) 
- #define l_noret         void __attribute__((noreturn)) 
- #elif defined(_MSC_VER) && _MSC_VER >= 1200 
- #define l_noret         void __declspec(noreturn) 
- #else 
- #define l_noret         void 
- #endif 
-   
- #endif 
-   
-   
- /* 
- ** Inline functions 
- */ 
- #if !defined(LUA_USE_C89) 
- #define l_inline        inline 
- #elif defined(__GNUC__) 
- #define l_inline        __inline__ 
- #else 
- #define l_inline        /* empty */ 
- #endif 
-   
- #define l_sinline       static l_inline 
-   
-   
- /* 
- ** type for virtual-machine instructions; 
- ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h) 
- */ 
- #if LUAI_IS32INT 
- typedef unsigned int l_uint32; 
- #else 
- typedef unsigned long l_uint32; 
- #endif 
-   
- typedef l_uint32 Instruction; 
-   
-   
-   
- /* 
- ** Maximum length for short strings, that is, strings that are 
- ** internalized. (Cannot be smaller than reserved words or tags for 
- ** metamethods, as these strings must be internalized; 
- ** #("function") = 8, #("__newindex") = 10.) 
- */ 
- #if !defined(LUAI_MAXSHORTLEN) 
- #define LUAI_MAXSHORTLEN        40 
- #endif 
-   
-   
- /* 
- ** Initial size for the string table (must be power of 2). 
- ** The Lua core alone registers ~50 strings (reserved words + 
- ** metaevent keys + a few others). Libraries would typically add 
- ** a few dozens more. 
- */ 
- #if !defined(MINSTRTABSIZE) 
- #define MINSTRTABSIZE   128 
- #endif 
-   
-   
- /* 
- ** Size of cache for strings in the API. 'N' is the number of 
- ** sets (better be a prime) and "M" is the size of each set (M == 1 
- ** makes a direct cache.) 
- */ 
- #if !defined(STRCACHE_N) 
- #define STRCACHE_N              53 
- #define STRCACHE_M              2 
- #endif 
-   
-   
- /* minimum size for string buffer */ 
- #if !defined(LUA_MINBUFFER) 
- #define LUA_MINBUFFER   32 
- #endif 
-   
-   
- /* 
- ** Maximum depth for nested C calls, syntactical nested non-terminals, 
- ** and other features implemented through recursion in C. (Value must 
- ** fit in a 16-bit unsigned integer. It must also be compatible with 
- ** the size of the C stack.) 
- */ 
- #if !defined(LUAI_MAXCCALLS) 
- #define LUAI_MAXCCALLS          200 
- #endif 
-   
-   
- /* 
- ** macros that are executed whenever program enters the Lua core 
- ** ('lua_lock') and leaves the core ('lua_unlock') 
- */ 
- #if !defined(lua_lock) 
- #define lua_lock(L)     ((void) 0) 
- #define lua_unlock(L)   ((void) 0) 
- #endif 
-   
- /* 
- ** macro executed during Lua functions at points where the 
- ** function can yield. 
- */ 
- #if !defined(luai_threadyield) 
- #define luai_threadyield(L)     {lua_unlock(L); lua_lock(L);} 
- #endif 
-   
-   
- /* 
- ** these macros allow user-specific actions 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 
-   
-   
-   
- /* 
- ** The luai_num* macros define the primitive operations over numbers. 
- */ 
-   
- /* floor division (defined as 'floor(a/b)') */ 
- #if !defined(luai_numidiv) 
- #define luai_numidiv(L,a,b)     ((void)L, l_floor(luai_numdiv(L,a,b))) 
- #endif 
-   
- /* float division */ 
- #if !defined(luai_numdiv) 
- #define luai_numdiv(L,a,b)      ((a)/(b)) 
- #endif 
-   
- /* 
- ** modulo: defined as 'a - floor(a/b)*b'; the direct computation 
- ** using this definition has several problems with rounding errors, 
- ** so it is better to use 'fmod'. 'fmod' gives the result of 
- ** 'a - trunc(a/b)*b', and therefore must be corrected when 
- ** 'trunc(a/b) ~= floor(a/b)'. That happens when the division has a 
- ** non-integer negative result: non-integer result is equivalent to 
- ** a non-zero remainder 'm'; negative result is equivalent to 'a' and 
- ** 'b' with different signs, or 'm' and 'b' with different signs 
- ** (as the result 'm' of 'fmod' has the same sign of 'a'). 
- */ 
- #if !defined(luai_nummod) 
- #define luai_nummod(L,a,b,m)  \ 
-   { (void)L; (m) = l_mathop(fmod)(a,b); \ 
-     if (((m) > 0) ? (b) < 0 : ((m) < 0 && (b) > 0)) (m) += (b); } 
- #endif 
-   
- /* exponentiation */ 
- #if !defined(luai_numpow) 
- #define luai_numpow(L,a,b)  \ 
-   ((void)L, (b == 2) ? (a)*(a) : l_mathop(pow)(a,b)) 
- #endif 
-   
- /* the others are quite standard operations */ 
- #if !defined(luai_numadd) 
- #define luai_numadd(L,a,b)      ((a)+(b)) 
- #define luai_numsub(L,a,b)      ((a)-(b)) 
- #define luai_nummul(L,a,b)      ((a)*(b)) 
- #define luai_numunm(L,a)        (-(a)) 
- #define luai_numeq(a,b)         ((a)==(b)) 
- #define luai_numlt(a,b)         ((a)<(b)) 
- #define luai_numle(a,b)         ((a)<=(b)) 
- #define luai_numgt(a,b)         ((a)>(b)) 
- #define luai_numge(a,b)         ((a)>=(b)) 
- #define luai_numisnan(a)        (!luai_numeq((a), (a))) 
- #endif 
-   
-   
-   
-   
-   
- /* 
- ** macro to control inclusion of some hard tests on stack reallocation 
- */ 
- #if !defined(HARDSTACKTESTS) 
- #define condmovestack(L,pre,pos)        ((void)0) 
- #else 
- /* realloc stack keeping its size */ 
- #define condmovestack(L,pre,pos)  \ 
-   { int sz_ = stacksize(L); pre; luaD_reallocstack((L), sz_, 0); pos; } 
- #endif 
-   
- #if !defined(HARDMEMTESTS) 
- #define condchangemem(L,pre,pos)        ((void)0) 
- #else 
- #define condchangemem(L,pre,pos)  \ 
-         { if (gcrunning(G(L))) { pre; luaC_fullgc(L, 0); pos; } } 
- #endif 
-   
- #endif 
-