1/* 2** $Id: llimits.h,v 1.103.1.1 2013/04/12 18:48:47 roberto Exp $ 3** Limits, basic types, and some other `installation-dependent' definitions 4** See Copyright Notice in lua.h 5*/ 6 7#ifndef llimits_h 8#define llimits_h 9 10 11#include <sys/lua/lua.h> 12 13 14typedef unsigned LUA_INT32 lu_int32; 15 16typedef LUAI_UMEM lu_mem; 17 18typedef LUAI_MEM l_mem; 19 20 21 22/* chars used as small naturals (so that `char' is reserved for characters) */ 23typedef unsigned char lu_byte; 24 25 26#define MAX_SIZET ((size_t)(~(size_t)0)-2) 27 28#define MAX_LUMEM ((lu_mem)(~(lu_mem)0)-2) 29 30#define MAX_LMEM ((l_mem) ((MAX_LUMEM >> 1) - 2)) 31 32 33#define MAX_INT (INT_MAX-2) /* maximum value of an int (-2 for safety) */ 34 35/* 36** conversion of pointer to integer 37** this is for hashing only; there is no problem if the integer 38** cannot hold the whole pointer value 39*/ 40#define IntPoint(p) ((unsigned int)(lu_mem)(p)) 41 42 43 44/* type to ensure maximum alignment */ 45#if !defined(LUAI_USER_ALIGNMENT_T) 46#define LUAI_USER_ALIGNMENT_T union { double u; void *s; long l; } 47#endif 48 49typedef LUAI_USER_ALIGNMENT_T L_Umaxalign; 50 51 52/* result of a `usual argument conversion' over lua_Number */ 53typedef LUAI_UACNUMBER l_uacNumber; 54 55 56/* internal assertions for in-house debugging */ 57#if defined(lua_assert) 58#define check_exp(c,e) (lua_assert(c), (e)) 59/* to avoid problems with conditions too long */ 60#define lua_longassert(c) { if (!(c)) lua_assert(0); } 61#else 62#define lua_assert(c) ((void)0) 63#define check_exp(c,e) (e) 64#define lua_longassert(c) ((void)0) 65#endif 66 67/* 68** assertion for checking API calls 69*/ 70#if !defined(luai_apicheck) 71 72#if defined(LUA_USE_APICHECK) 73#include <assert.h> 74#define luai_apicheck(L,e) assert(e) 75#else 76#define luai_apicheck(L,e) lua_assert(e) 77#endif 78 79#endif 80 81#define api_check(l,e,msg) luai_apicheck(l,(e) && msg) 82 83 84#if !defined(UNUSED) 85#define UNUSED(x) ((void)(x)) /* to avoid warnings */ 86#endif 87 88 89#define cast(t, exp) ((t)(exp)) 90 91#define cast_byte(i) cast(lu_byte, (i)) 92#define cast_num(i) cast(lua_Number, (i)) 93#define cast_int(i) cast(int, (i)) 94#define cast_uchar(i) cast(unsigned char, (i)) 95 96 97/* 98** non-return type 99** 100** Suppress noreturn attribute in kernel builds to avoid objtool check warnings 101*/ 102#if defined(__GNUC__) && !defined(_KERNEL) 103#define l_noret void __attribute__((noreturn)) 104#elif defined(_MSC_VER) 105#define l_noret void __declspec(noreturn) 106#else 107#define l_noret void 108#endif 109 110 111 112/* 113** maximum depth for nested C calls and syntactical nested non-terminals 114** in a program. (Value must fit in an unsigned short int.) 115** 116** Note: On amd64 platform, the limit has been measured to be 45. We set 117** the maximum lower to give a margin for changing the amount of stack 118** used by various functions involved in parsing and executing code. 119*/ 120#if !defined(LUAI_MAXCCALLS) 121#define LUAI_MAXCCALLS 20 122#endif 123 124/* 125 * Minimum amount of available stack space (in bytes) to make a C call. With 126 * gsub() recursion, the stack space between each luaD_call() is 1256 bytes. 127 */ 128#define LUAI_MINCSTACK 4096 129 130/* 131** maximum number of upvalues in a closure (both C and Lua). (Value 132** must fit in an unsigned char.) 133*/ 134#define MAXUPVAL UCHAR_MAX 135 136 137/* 138** type for virtual-machine instructions 139** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h) 140*/ 141typedef lu_int32 Instruction; 142 143 144 145/* maximum stack for a Lua function */ 146#define MAXSTACK 250 147 148 149 150/* minimum size for the string table (must be power of 2) */ 151#if !defined(MINSTRTABSIZE) 152#define MINSTRTABSIZE 32 153#endif 154 155 156/* minimum size for string buffer */ 157#if !defined(LUA_MINBUFFER) 158#define LUA_MINBUFFER 32 159#endif 160 161 162#if !defined(lua_lock) 163#define lua_lock(L) ((void) 0) 164#define lua_unlock(L) ((void) 0) 165#endif 166 167#if !defined(luai_threadyield) 168#define luai_threadyield(L) {lua_unlock(L); lua_lock(L);} 169#endif 170 171 172/* 173** these macros allow user-specific actions on threads when you defined 174** LUAI_EXTRASPACE and need to do something extra when a thread is 175** created/deleted/resumed/yielded. 176*/ 177#if !defined(luai_userstateopen) 178#define luai_userstateopen(L) ((void)L) 179#endif 180 181#if !defined(luai_userstateclose) 182#define luai_userstateclose(L) ((void)L) 183#endif 184 185#if !defined(luai_userstatethread) 186#define luai_userstatethread(L,L1) ((void)L) 187#endif 188 189#if !defined(luai_userstatefree) 190#define luai_userstatefree(L,L1) ((void)L) 191#endif 192 193#if !defined(luai_userstateresume) 194#define luai_userstateresume(L,n) ((void)L) 195#endif 196 197#if !defined(luai_userstateyield) 198#define luai_userstateyield(L,n) ((void)L) 199#endif 200 201/* 202** lua_number2int is a macro to convert lua_Number to int. 203** lua_number2integer is a macro to convert lua_Number to lua_Integer. 204** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned. 205** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number. 206** luai_hashnum is a macro to hash a lua_Number value into an integer. 207** The hash must be deterministic and give reasonable values for 208** both small and large values (outside the range of integers). 209*/ 210 211#if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK) /* { */ 212/* trick with Microsoft assembler for X86 */ 213 214#define lua_number2int(i,n) __asm {__asm fld n __asm fistp i} 215#define lua_number2integer(i,n) lua_number2int(i, n) 216#define lua_number2unsigned(i,n) \ 217 {__int64 l; __asm {__asm fld n __asm fistp l} i = (unsigned int)l;} 218 219 220#elif defined(LUA_IEEE754TRICK) /* }{ */ 221/* the next trick should work on any machine using IEEE754 with 222 a 32-bit int type */ 223 224union luai_Cast { double l_d; LUA_INT32 l_p[2]; }; 225 226#if !defined(LUA_IEEEENDIAN) /* { */ 227#define LUAI_EXTRAIEEE \ 228 static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)}; 229#define LUA_IEEEENDIANLOC (ieeeendian.l_p[1] == 33) 230#else 231#define LUA_IEEEENDIANLOC LUA_IEEEENDIAN 232#define LUAI_EXTRAIEEE /* empty */ 233#endif /* } */ 234 235#define lua_number2int32(i,n,t) \ 236 { LUAI_EXTRAIEEE \ 237 volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \ 238 (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; } 239 240#define luai_hashnum(i,n) \ 241 { volatile union luai_Cast u; u.l_d = (n) + 1.0; /* avoid -0 */ \ 242 (i) = u.l_p[0]; (i) += u.l_p[1]; } /* add double bits for his hash */ 243 244#define lua_number2int(i,n) lua_number2int32(i, n, int) 245#define lua_number2unsigned(i,n) lua_number2int32(i, n, lua_Unsigned) 246 247/* the trick can be expanded to lua_Integer when it is a 32-bit value */ 248#if defined(LUA_IEEELL) 249#define lua_number2integer(i,n) lua_number2int32(i, n, lua_Integer) 250#endif 251 252#endif /* } */ 253 254 255/* the following definitions always work, but may be slow */ 256 257#if !defined(lua_number2int) 258#define lua_number2int(i,n) ((i)=(int)(n)) 259#endif 260 261#if !defined(lua_number2integer) 262#define lua_number2integer(i,n) ((i)=(lua_Integer)(n)) 263#endif 264 265#if !defined(lua_number2unsigned) /* { */ 266/* the following definition assures proper modulo behavior */ 267#if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT) 268#include <math.h> 269#define SUPUNSIGNED ((lua_Number)(~(lua_Unsigned)0) + 1) 270#define lua_number2unsigned(i,n) \ 271 ((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED)) 272#else 273#define lua_number2unsigned(i,n) ((i)=(lua_Unsigned)(n)) 274#endif 275#endif /* } */ 276 277 278#if !defined(lua_unsigned2number) 279/* on several machines, coercion from unsigned to double is slow, 280 so it may be worth to avoid */ 281#define lua_unsigned2number(u) \ 282 (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u)) 283#endif 284 285 286 287#if defined(ltable_c) && !defined(luai_hashnum) 288 289#define luai_hashnum(i,n) (i = lcompat_hashnum(n)) 290 291#endif 292 293 294 295/* 296** macro to control inclusion of some hard tests on stack reallocation 297*/ 298#if !defined(HARDSTACKTESTS) 299#define condmovestack(L) ((void)0) 300#else 301/* realloc stack keeping its size */ 302#define condmovestack(L) luaD_reallocstack((L), (L)->stacksize) 303#endif 304 305#if !defined(HARDMEMTESTS) 306#define condchangemem(L) condmovestack(L) 307#else 308#define condchangemem(L) \ 309 ((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1))) 310#endif 311 312#endif 313