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? */ 28typedef LUAI_UMEM lu_mem; 29typedef LUAI_MEM l_mem; 30#elif LUAI_IS32INT /* }{ */ 31typedef size_t lu_mem; 32typedef ptrdiff_t l_mem; 33#else /* 16-bit ints */ /* }{ */ 34typedef unsigned long lu_mem; 35typedef long l_mem; 36#endif /* } */ 37 38 39/* chars used as small naturals (so that 'char' is reserved for characters) */ 40typedef unsigned char lu_byte; 41typedef 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 101typedef LUAI_UACNUMBER l_uacNumber; 102#endif /* _KERNEL */ 103typedef 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 206typedef unsigned int l_uint32; 207#else 208typedef unsigned long l_uint32; 209#endif 210 211typedef 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