1 /* $NetBSD: llimits.h,v 1.12 2023/06/08 21:12:08 nikita Exp $ */ 2 3 /* 4 ** Id: llimits.h 5 ** Limits, basic types, and some other 'installation-dependent' definitions 6 ** See Copyright Notice in lua.h 7 */ 8 9 #ifndef llimits_h 10 #define llimits_h 11 12 13 #ifndef _KERNEL 14 #include <limits.h> 15 #include <stddef.h> 16 #endif /* _KERNEL */ 17 18 19 #include "lua.h" 20 21 22 /* 23 ** 'lu_mem' and 'l_mem' are unsigned/signed integers big enough to count 24 ** the total memory used by Lua (in bytes). Usually, 'size_t' and 25 ** 'ptrdiff_t' should work, but we use 'long' for 16-bit machines. 26 */ 27 #if defined(LUAI_MEM) /* { external definitions? */ 28 typedef LUAI_UMEM lu_mem; 29 typedef LUAI_MEM l_mem; 30 #elif LUAI_IS32INT /* }{ */ 31 typedef size_t lu_mem; 32 typedef ptrdiff_t l_mem; 33 #else /* 16-bit ints */ /* }{ */ 34 typedef unsigned long lu_mem; 35 typedef long l_mem; 36 #endif /* } */ 37 38 39 /* chars used as small naturals (so that 'char' is reserved for characters) */ 40 typedef unsigned char lu_byte; 41 typedef signed char ls_byte; 42 43 44 /* maximum value for size_t */ 45 #define MAX_SIZET ((size_t)(~(size_t)0)) 46 47 /* maximum size visible for Lua (must be representable in a lua_Integer) */ 48 #define MAX_SIZE (sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \ 49 : (size_t)(LUA_MAXINTEGER)) 50 51 52 #define MAX_LUMEM ((lu_mem)(~(lu_mem)0)) 53 54 #define MAX_LMEM ((l_mem)(MAX_LUMEM >> 1)) 55 56 57 #define MAX_INT INT_MAX /* maximum value of an int */ 58 59 60 /* 61 ** floor of the log2 of the maximum signed value for integral type 't'. 62 ** (That is, maximum 'n' such that '2^n' fits in the given signed type.) 63 */ 64 #define log2maxs(t) (sizeof(t) * 8 - 2) 65 66 67 /* 68 ** test whether an unsigned value is a power of 2 (or zero) 69 */ 70 #define ispow2(x) (((x) & ((x) - 1)) == 0) 71 72 73 /* number of chars of a literal string without the ending \0 */ 74 #define LL(x) (sizeof(x)/sizeof(char) - 1) 75 76 77 /* 78 ** conversion of pointer to unsigned integer: this is for hashing only; 79 ** there is no problem if the integer cannot hold the whole pointer 80 ** value. (In strict ISO C this may cause undefined behavior, but no 81 ** actual machine seems to bother.) 82 */ 83 #if !defined(LUA_USE_C89) && defined(__STDC_VERSION__) && \ 84 __STDC_VERSION__ >= 199901L 85 #include <stdint.h> 86 #if defined(UINTPTR_MAX) /* even in C99 this type is optional */ 87 #define L_P2I uintptr_t 88 #else /* no 'intptr'? */ 89 #define L_P2I uintmax_t /* use the largest available integer */ 90 #endif 91 #else /* C89 option */ 92 #define L_P2I size_t 93 #endif 94 95 #define point2uint(p) ((unsigned int)((L_P2I)(p) & UINT_MAX)) 96 97 98 99 /* types of 'usual argument conversions' for lua_Number and lua_Integer */ 100 #ifndef _KERNEL 101 typedef LUAI_UACNUMBER l_uacNumber; 102 #endif /* _KERNEL */ 103 typedef LUAI_UACINT l_uacInt; 104 105 106 /* 107 ** Internal assertions for in-house debugging 108 */ 109 #if defined LUAI_ASSERT 110 #undef NDEBUG 111 #include <assert.h> 112 #define lua_assert(c) assert(c) 113 #endif 114 115 #if defined(lua_assert) 116 #define check_exp(c,e) (lua_assert(c), (e)) 117 /* to avoid problems with conditions too long */ 118 #define lua_longassert(c) ((c) ? (void)0 : lua_assert(0)) 119 #else 120 #define lua_assert(c) ((void)0) 121 #define check_exp(c,e) (e) 122 #define lua_longassert(c) ((void)0) 123 #endif 124 125 /* 126 ** assertion for checking API calls 127 */ 128 #if !defined(luai_apicheck) 129 #define luai_apicheck(l,e) ((void)l, lua_assert(e)) 130 #endif 131 132 #define api_check(l,e,msg) luai_apicheck(l,(e) && msg) 133 134 135 /* macro to avoid warnings about unused variables */ 136 #if !defined(UNUSED) 137 #define UNUSED(x) ((void)(x)) 138 #endif 139 140 141 /* type casts (a macro highlights casts in the code) */ 142 #define cast(t, exp) ((t)(exp)) 143 144 #define cast_void(i) cast(void, (i)) 145 #define cast_voidp(i) cast(void *, (i)) 146 #define cast_num(i) cast(lua_Number, (i)) 147 #define cast_int(i) cast(int, (i)) 148 #define cast_uint(i) cast(unsigned int, (i)) 149 #define cast_byte(i) cast(lu_byte, (i)) 150 #define cast_uchar(i) cast(unsigned char, (i)) 151 #define cast_char(i) cast(char, (i)) 152 #define cast_charp(i) cast(char *, (i)) 153 #define cast_sizet(i) cast(size_t, (i)) 154 155 156 /* cast a signed lua_Integer to lua_Unsigned */ 157 #if !defined(l_castS2U) 158 #define l_castS2U(i) ((lua_Unsigned)(i)) 159 #endif 160 161 /* 162 ** cast a lua_Unsigned to a signed lua_Integer; this cast is 163 ** not strict ISO C, but two-complement architectures should 164 ** work fine. 165 */ 166 #if !defined(l_castU2S) 167 #define l_castU2S(i) ((lua_Integer)(i)) 168 #endif 169 170 171 /* 172 ** non-return type 173 */ 174 #if !defined(l_noret) 175 176 #if defined(__GNUC__) 177 #define l_noret void __attribute__((noreturn)) 178 #elif defined(_MSC_VER) && _MSC_VER >= 1200 179 #define l_noret void __declspec(noreturn) 180 #else 181 #define l_noret void 182 #endif 183 184 #endif 185 186 187 /* 188 ** Inline functions 189 */ 190 #if !defined(LUA_USE_C89) 191 #define l_inline inline 192 #elif defined(__GNUC__) 193 #define l_inline __inline__ 194 #else 195 #define l_inline /* empty */ 196 #endif 197 198 #define l_sinline static l_inline 199 200 201 /* 202 ** type for virtual-machine instructions; 203 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h) 204 */ 205 #if LUAI_IS32INT 206 typedef unsigned int l_uint32; 207 #else 208 typedef unsigned long l_uint32; 209 #endif 210 211 typedef l_uint32 Instruction; 212 213 214 215 /* 216 ** Maximum length for short strings, that is, strings that are 217 ** internalized. (Cannot be smaller than reserved words or tags for 218 ** metamethods, as these strings must be internalized; 219 ** #("function") = 8, #("__newindex") = 10.) 220 */ 221 #if !defined(LUAI_MAXSHORTLEN) 222 #define LUAI_MAXSHORTLEN 40 223 #endif 224 225 226 /* 227 ** Initial size for the string table (must be power of 2). 228 ** The Lua core alone registers ~50 strings (reserved words + 229 ** metaevent keys + a few others). Libraries would typically add 230 ** a few dozens more. 231 */ 232 #if !defined(MINSTRTABSIZE) 233 #define MINSTRTABSIZE 128 234 #endif 235 236 237 /* 238 ** Size of cache for strings in the API. 'N' is the number of 239 ** sets (better be a prime) and "M" is the size of each set (M == 1 240 ** makes a direct cache.) 241 */ 242 #if !defined(STRCACHE_N) 243 #define STRCACHE_N 53 244 #define STRCACHE_M 2 245 #endif 246 247 248 /* minimum size for string buffer */ 249 #if !defined(LUA_MINBUFFER) 250 #define LUA_MINBUFFER 32 251 #endif 252 253 254 /* 255 ** Maximum depth for nested C calls, syntactical nested non-terminals, 256 ** and other features implemented through recursion in C. (Value must 257 ** fit in a 16-bit unsigned integer. It must also be compatible with 258 ** the size of the C stack.) 259 */ 260 #if !defined(LUAI_MAXCCALLS) 261 #define LUAI_MAXCCALLS 200 262 #endif 263 264 265 /* 266 ** macros that are executed whenever program enters the Lua core 267 ** ('lua_lock') and leaves the core ('lua_unlock') 268 */ 269 #if !defined(lua_lock) 270 #define lua_lock(L) ((void) 0) 271 #define lua_unlock(L) ((void) 0) 272 #endif 273 274 /* 275 ** macro executed during Lua functions at points where the 276 ** function can yield. 277 */ 278 #if !defined(luai_threadyield) 279 #define luai_threadyield(L) {lua_unlock(L); lua_lock(L);} 280 #endif 281 282 283 /* 284 ** these macros allow user-specific actions when a thread is 285 ** created/deleted/resumed/yielded. 286 */ 287 #if !defined(luai_userstateopen) 288 #define luai_userstateopen(L) ((void)L) 289 #endif 290 291 #if !defined(luai_userstateclose) 292 #define luai_userstateclose(L) ((void)L) 293 #endif 294 295 #if !defined(luai_userstatethread) 296 #define luai_userstatethread(L,L1) ((void)L) 297 #endif 298 299 #if !defined(luai_userstatefree) 300 #define luai_userstatefree(L,L1) ((void)L) 301 #endif 302 303 #if !defined(luai_userstateresume) 304 #define luai_userstateresume(L,n) ((void)L) 305 #endif 306 307 #if !defined(luai_userstateyield) 308 #define luai_userstateyield(L,n) ((void)L) 309 #endif 310 311 312 313 /* 314 ** The luai_num* macros define the primitive operations over numbers. 315 */ 316 317 /* floor division (defined as 'floor(a/b)') */ 318 #if !defined(luai_numidiv) 319 #define luai_numidiv(L,a,b) ((void)L, l_floor(luai_numdiv(L,a,b))) 320 #endif 321 322 /* float division */ 323 #if !defined(luai_numdiv) 324 #define luai_numdiv(L,a,b) ((a)/(b)) 325 #endif 326 327 /* 328 ** modulo: defined as 'a - floor(a/b)*b'; the direct computation 329 ** using this definition has several problems with rounding errors, 330 ** so it is better to use 'fmod'. 'fmod' gives the result of 331 ** 'a - trunc(a/b)*b', and therefore must be corrected when 332 ** 'trunc(a/b) ~= floor(a/b)'. That happens when the division has a 333 ** non-integer negative result: non-integer result is equivalent to 334 ** a non-zero remainder 'm'; negative result is equivalent to 'a' and 335 ** 'b' with different signs, or 'm' and 'b' with different signs 336 ** (as the result 'm' of 'fmod' has the same sign of 'a'). 337 */ 338 #if !defined(luai_nummod) 339 #define luai_nummod(L,a,b,m) \ 340 { (void)L; (m) = l_mathop(fmod)(a,b); \ 341 if (((m) > 0) ? (b) < 0 : ((m) < 0 && (b) > 0)) (m) += (b); } 342 #endif 343 344 /* exponentiation */ 345 #if !defined(luai_numpow) 346 #define luai_numpow(L,a,b) \ 347 ((void)L, (b == 2) ? (a)*(a) : l_mathop(pow)(a,b)) 348 #endif 349 350 /* the others are quite standard operations */ 351 #if !defined(luai_numadd) 352 #define luai_numadd(L,a,b) ((a)+(b)) 353 #define luai_numsub(L,a,b) ((a)-(b)) 354 #define luai_nummul(L,a,b) ((a)*(b)) 355 #define luai_numunm(L,a) (-(a)) 356 #define luai_numeq(a,b) ((a)==(b)) 357 #define luai_numlt(a,b) ((a)<(b)) 358 #define luai_numle(a,b) ((a)<=(b)) 359 #define luai_numgt(a,b) ((a)>(b)) 360 #define luai_numge(a,b) ((a)>=(b)) 361 #define luai_numisnan(a) (!luai_numeq((a), (a))) 362 #endif 363 364 365 366 367 368 /* 369 ** macro to control inclusion of some hard tests on stack reallocation 370 */ 371 #if !defined(HARDSTACKTESTS) 372 #define condmovestack(L,pre,pos) ((void)0) 373 #else 374 /* realloc stack keeping its size */ 375 #define condmovestack(L,pre,pos) \ 376 { int sz_ = stacksize(L); pre; luaD_reallocstack((L), sz_, 0); pos; } 377 #endif 378 379 #if !defined(HARDMEMTESTS) 380 #define condchangemem(L,pre,pos) ((void)0) 381 #else 382 #define condchangemem(L,pre,pos) \ 383 { if (gcrunning(G(L))) { pre; luaC_fullgc(L, 0); pos; } } 384 #endif 385 386 #endif 387