| 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 |