/* ** $Id: llimits.h,v 1.85 2010/12/10 13:40:22 roberto Exp roberto $ ** Limits, basic types, and some other `installation-dependent' definitions ** See Copyright Notice in lua.h */ #ifndef llimits_h #define llimits_h #include #include #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 MIN_LMEM ((l_mem)~((~(lu_mem)0)>>1)) #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)) #else #define lua_assert(c) /* empty */ #define check_exp(c,e) (e) #endif /* ** assertion for checking API calls */ #if defined(LUA_USE_APICHECK) #include #define luai_apicheck(L,e) { (void)L; assert(e); } #elif !defined(luai_apicheck) #define luai_apicheck(L,e) lua_assert(e) #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)) /* ** 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 integer 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_IEEEENDIAN (ieeeendian.l_p[1] == 33) #else #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_IEEEENDIAN]; } #define luai_hashnum(i,n) \ { volatile union luai_Cast u; u.l_d = (n) + 1.0; /* avoid -0 */ \ (i) = u.l_p[0] + u.l_p[1]; } /* add double bits for his hash */ #define lua_number2int(i,n) lua_number2int32(i, n, int) #define lua_number2integer(i,n) lua_number2int32(i, n, lua_Integer) #define lua_number2unsigned(i,n) lua_number2int32(i, n, lua_Unsigned) #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 #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 #include #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)(gcstopped(G(L)) || (luaC_fullgc(L, 0), 1))) #endif #endif