1 /* 2 ** $Id: llimits.h,v 1.103 2013/02/20 14:08:56 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 <limits.h> 12 #include <stddef.h> 13 14 15 #include "lua.h" 16 17 18 typedef unsigned LUA_INT32 lu_int32; 19 20 typedef LUAI_UMEM lu_mem; 21 22 typedef LUAI_MEM l_mem; 23 24 25 26 /* chars used as small naturals (so that `char' is reserved for characters) */ 27 typedef unsigned char lu_byte; 28 29 30 #define MAX_SIZET ((size_t)(~(size_t)0)-2) 31 32 #define MAX_LUMEM ((lu_mem)(~(lu_mem)0)-2) 33 34 #define MAX_LMEM ((l_mem) ((MAX_LUMEM >> 1) - 2)) 35 36 37 #define MAX_INT (INT_MAX-2) /* maximum value of an int (-2 for safety) */ 38 39 /* 40 ** conversion of pointer to integer 41 ** this is for hashing only; there is no problem if the integer 42 ** cannot hold the whole pointer value 43 */ 44 #define IntPoint(p) ((unsigned int)(lu_mem)(p)) 45 46 47 48 /* type to ensure maximum alignment */ 49 #if !defined(LUAI_USER_ALIGNMENT_T) 50 #define LUAI_USER_ALIGNMENT_T union { double u; void *s; long l; } 51 #endif 52 53 typedef LUAI_USER_ALIGNMENT_T L_Umaxalign; 54 55 56 /* result of a `usual argument conversion' over lua_Number */ 57 typedef LUAI_UACNUMBER l_uacNumber; 58 59 60 /* internal assertions for in-house debugging */ 61 #if defined(lua_assert) 62 #define check_exp(c,e) (lua_assert(c), (e)) 63 /* to avoid problems with conditions too long */ 64 #define lua_longassert(c) { if (!(c)) lua_assert(0); } 65 #else 66 #define lua_assert(c) ((void)0) 67 #define check_exp(c,e) (e) 68 #define lua_longassert(c) ((void)0) 69 #endif 70 71 /* 72 ** assertion for checking API calls 73 */ 74 #if !defined(luai_apicheck) 75 76 #if defined(LUA_USE_APICHECK) 77 #include <assert.h> 78 #define luai_apicheck(L,e) assert(e) 79 #else 80 #define luai_apicheck(L,e) lua_assert(e) 81 #endif 82 83 #endif 84 85 #define api_check(l,e,msg) luai_apicheck(l,(e) && msg) 86 87 88 #if !defined(UNUSED) 89 #define UNUSED(x) ((void)(x)) /* to avoid warnings */ 90 #endif 91 92 93 #define cast(t, exp) ((t)(exp)) 94 95 #define cast_byte(i) cast(lu_byte, (i)) 96 #define cast_num(i) cast(lua_Number, (i)) 97 #define cast_int(i) cast(int, (i)) 98 #define cast_uchar(i) cast(unsigned char, (i)) 99 100 101 /* 102 ** non-return type 103 */ 104 #if defined(__GNUC__) 105 #define l_noret void __attribute__((noreturn)) 106 #elif defined(_MSC_VER) 107 #define l_noret void __declspec(noreturn) 108 #else 109 #define l_noret void 110 #endif 111 112 113 114 /* 115 ** maximum depth for nested C calls and syntactical nested non-terminals 116 ** in a program. (Value must fit in an unsigned short int.) 117 */ 118 #if !defined(LUAI_MAXCCALLS) 119 #define LUAI_MAXCCALLS 200 120 #endif 121 122 /* 123 ** maximum number of upvalues in a closure (both C and Lua). (Value 124 ** must fit in an unsigned char.) 125 */ 126 #define MAXUPVAL UCHAR_MAX 127 128 129 /* 130 ** type for virtual-machine instructions 131 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h) 132 */ 133 typedef lu_int32 Instruction; 134 135 136 137 /* maximum stack for a Lua function */ 138 #define MAXSTACK 250 139 140 141 142 /* minimum size for the string table (must be power of 2) */ 143 #if !defined(MINSTRTABSIZE) 144 #define MINSTRTABSIZE 32 145 #endif 146 147 148 /* minimum size for string buffer */ 149 #if !defined(LUA_MINBUFFER) 150 #define LUA_MINBUFFER 32 151 #endif 152 153 154 #if !defined(lua_lock) 155 #define lua_lock(L) ((void) 0) 156 #define lua_unlock(L) ((void) 0) 157 #endif 158 159 #if !defined(luai_threadyield) 160 #define luai_threadyield(L) {lua_unlock(L); lua_lock(L);} 161 #endif 162 163 164 /* 165 ** these macros allow user-specific actions on threads when you defined 166 ** LUAI_EXTRASPACE and need to do something extra when a thread is 167 ** created/deleted/resumed/yielded. 168 */ 169 #if !defined(luai_userstateopen) 170 #define luai_userstateopen(L) ((void)L) 171 #endif 172 173 #if !defined(luai_userstateclose) 174 #define luai_userstateclose(L) ((void)L) 175 #endif 176 177 #if !defined(luai_userstatethread) 178 #define luai_userstatethread(L,L1) ((void)L) 179 #endif 180 181 #if !defined(luai_userstatefree) 182 #define luai_userstatefree(L,L1) ((void)L) 183 #endif 184 185 #if !defined(luai_userstateresume) 186 #define luai_userstateresume(L,n) ((void)L) 187 #endif 188 189 #if !defined(luai_userstateyield) 190 #define luai_userstateyield(L,n) ((void)L) 191 #endif 192 193 /* 194 ** lua_number2int is a macro to convert lua_Number to int. 195 ** lua_number2integer is a macro to convert lua_Number to lua_Integer. 196 ** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned. 197 ** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number. 198 ** luai_hashnum is a macro to hash a lua_Number value into an integer. 199 ** The hash must be deterministic and give reasonable values for 200 ** both small and large values (outside the range of integers). 201 */ 202 203 #if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK) /* { */ 204 /* trick with Microsoft assembler for X86 */ 205 206 #define lua_number2int(i,n) __asm {__asm fld n __asm fistp i} 207 #define lua_number2integer(i,n) lua_number2int(i, n) 208 #define lua_number2unsigned(i,n) \ 209 {__int64 l; __asm {__asm fld n __asm fistp l} i = (unsigned int)l;} 210 211 212 #elif defined(LUA_IEEE754TRICK) /* }{ */ 213 /* the next trick should work on any machine using IEEE754 with 214 a 32-bit int type */ 215 216 union luai_Cast { double l_d; LUA_INT32 l_p[2]; }; 217 218 #if !defined(LUA_IEEEENDIAN) /* { */ 219 #define LUAI_EXTRAIEEE \ 220 static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)}; 221 #define LUA_IEEEENDIANLOC (ieeeendian.l_p[1] == 33) 222 #else 223 #define LUA_IEEEENDIANLOC LUA_IEEEENDIAN 224 #define LUAI_EXTRAIEEE /* empty */ 225 #endif /* } */ 226 227 #define lua_number2int32(i,n,t) \ 228 { LUAI_EXTRAIEEE \ 229 volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \ 230 (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; } 231 232 #define luai_hashnum(i,n) \ 233 { volatile union luai_Cast u; u.l_d = (n) + 1.0; /* avoid -0 */ \ 234 (i) = u.l_p[0]; (i) += u.l_p[1]; } /* add double bits for his hash */ 235 236 #define lua_number2int(i,n) lua_number2int32(i, n, int) 237 #define lua_number2unsigned(i,n) lua_number2int32(i, n, lua_Unsigned) 238 239 /* the trick can be expanded to lua_Integer when it is a 32-bit value */ 240 #if defined(LUA_IEEELL) 241 #define lua_number2integer(i,n) lua_number2int32(i, n, lua_Integer) 242 #endif 243 244 #endif /* } */ 245 246 247 /* the following definitions always work, but may be slow */ 248 249 #if !defined(lua_number2int) 250 #define lua_number2int(i,n) ((i)=(int)(n)) 251 #endif 252 253 #if !defined(lua_number2integer) 254 #define lua_number2integer(i,n) ((i)=(lua_Integer)(n)) 255 #endif 256 257 #if !defined(lua_number2unsigned) /* { */ 258 /* the following definition assures proper modulo behavior */ 259 #if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT) 260 #include <math.h> 261 #define SUPUNSIGNED ((lua_Number)(~(lua_Unsigned)0) + 1) 262 #define lua_number2unsigned(i,n) \ 263 ((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED)) 264 #else 265 #define lua_number2unsigned(i,n) ((i)=(lua_Unsigned)(n)) 266 #endif 267 #endif /* } */ 268 269 270 #if !defined(lua_unsigned2number) 271 /* on several machines, coercion from unsigned to double is slow, 272 so it may be worth to avoid */ 273 #define lua_unsigned2number(u) \ 274 (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u)) 275 #endif 276 277 278 279 #if defined(ltable_c) && !defined(luai_hashnum) 280 281 #include <float.h> 282 #include <math.h> 283 284 #define luai_hashnum(i,n) { int e; \ 285 n = l_mathop(frexp)(n, &e) * (lua_Number)(INT_MAX - DBL_MAX_EXP); \ 286 lua_number2int(i, n); i += e; } 287 288 #endif 289 290 291 292 /* 293 ** macro to control inclusion of some hard tests on stack reallocation 294 */ 295 #if !defined(HARDSTACKTESTS) 296 #define condmovestack(L) ((void)0) 297 #else 298 /* realloc stack keeping its size */ 299 #define condmovestack(L) luaD_reallocstack((L), (L)->stacksize) 300 #endif 301 302 #if !defined(HARDMEMTESTS) 303 #define condchangemem(L) condmovestack(L) 304 #else 305 #define condchangemem(L) \ 306 ((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1))) 307 #endif 308 309 #endif 310