1 /* $NetBSD: llimits.h,v 1.9 2017/04/26 13:17:33 mbalmer Exp $ */ 2 3 /* 4 ** Id: llimits.h,v 1.141 2015/11/19 19:16:22 roberto Exp 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 ** 'lu_mem' and 'l_mem' are unsigned/signed integers big enough to count 23 ** the total memory used by Lua (in bytes). Usually, 'size_t' and 24 ** 'ptrdiff_t' should work, but we use 'long' for 16-bit machines. 25 */ 26 #if defined(LUAI_MEM) /* { external definitions? */ 27 typedef LUAI_UMEM lu_mem; 28 typedef LUAI_MEM l_mem; 29 #elif LUAI_BITSINT >= 32 /* }{ */ 30 typedef size_t lu_mem; 31 typedef ptrdiff_t l_mem; 32 #else /* 16-bit ints */ /* }{ */ 33 typedef unsigned long lu_mem; 34 typedef long l_mem; 35 #endif /* } */ 36 37 38 /* chars used as small naturals (so that 'char' is reserved for characters) */ 39 typedef unsigned char lu_byte; 40 41 42 /* maximum value for size_t */ 43 #define MAX_SIZET ((size_t)(~(size_t)0)) 44 45 /* maximum size visible for Lua (must be representable in a lua_Integer */ 46 #define MAX_SIZE (sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \ 47 : (size_t)(LUA_MAXINTEGER)) 48 49 50 #define MAX_LUMEM ((lu_mem)(~(lu_mem)0)) 51 52 #define MAX_LMEM ((l_mem)(MAX_LUMEM >> 1)) 53 54 55 #define MAX_INT INT_MAX /* maximum value of an int */ 56 57 58 /* 59 ** conversion of pointer to unsigned integer: 60 ** this is for hashing only; there is no problem if the integer 61 ** cannot hold the whole pointer value 62 */ 63 #define point2uint(p) ((unsigned int)((size_t)(p) & UINT_MAX)) 64 65 66 67 /* type to ensure maximum alignment */ 68 #if defined(LUAI_USER_ALIGNMENT_T) 69 typedef LUAI_USER_ALIGNMENT_T L_Umaxalign; 70 #else 71 typedef union { 72 #ifndef _KERNEL 73 lua_Number n; 74 double u; 75 #endif /* _KERNEL */ 76 void *s; 77 lua_Integer i; 78 long l; 79 } L_Umaxalign; 80 #endif 81 82 83 84 /* types of 'usual argument conversions' for lua_Number and lua_Integer */ 85 #ifndef _KERNEL 86 typedef LUAI_UACNUMBER l_uacNumber; 87 #endif /* _KERNEL */ 88 typedef LUAI_UACINT l_uacInt; 89 90 91 /* internal assertions for in-house debugging */ 92 #if defined(lua_assert) 93 #define check_exp(c,e) (lua_assert(c), (e)) 94 /* to avoid problems with conditions too long */ 95 #define lua_longassert(c) ((c) ? (void)0 : lua_assert(0)) 96 #else 97 #define lua_assert(c) ((void)0) 98 #define check_exp(c,e) (e) 99 #define lua_longassert(c) ((void)0) 100 #endif 101 102 /* 103 ** assertion for checking API calls 104 */ 105 #if !defined(luai_apicheck) 106 #define luai_apicheck(l,e) lua_assert(e) 107 #endif 108 109 #define api_check(l,e,msg) luai_apicheck(l,(e) && msg) 110 111 112 /* macro to avoid warnings about unused variables */ 113 #if !defined(UNUSED) 114 #define UNUSED(x) ((void)(x)) 115 #endif 116 117 118 /* type casts (a macro highlights casts in the code) */ 119 #define cast(t, exp) ((t)(exp)) 120 121 #define cast_void(i) cast(void, (i)) 122 #define cast_byte(i) cast(lu_byte, (i)) 123 #define cast_num(i) cast(lua_Number, (i)) 124 #define cast_int(i) cast(int, (i)) 125 #define cast_uchar(i) cast(unsigned char, (i)) 126 127 128 /* cast a signed lua_Integer to lua_Unsigned */ 129 #if !defined(l_castS2U) 130 #define l_castS2U(i) ((lua_Unsigned)(i)) 131 #endif 132 133 /* 134 ** cast a lua_Unsigned to a signed lua_Integer; this cast is 135 ** not strict ISO C, but two-complement architectures should 136 ** work fine. 137 */ 138 #if !defined(l_castU2S) 139 #define l_castU2S(i) ((lua_Integer)(i)) 140 #endif 141 142 143 /* 144 ** non-return type 145 */ 146 #if defined(__GNUC__) 147 #define l_noret void __attribute__((noreturn)) 148 #elif defined(_MSC_VER) && _MSC_VER >= 1200 149 #define l_noret void __declspec(noreturn) 150 #else 151 #define l_noret void 152 #endif 153 154 155 156 /* 157 ** maximum depth for nested C calls and syntactical nested non-terminals 158 ** in a program. (Value must fit in an unsigned short int.) 159 */ 160 #if !defined(LUAI_MAXCCALLS) 161 #define LUAI_MAXCCALLS 200 162 #endif 163 164 165 166 /* 167 ** type for virtual-machine instructions; 168 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h) 169 */ 170 #if LUAI_BITSINT >= 32 171 typedef unsigned int Instruction; 172 #else 173 typedef unsigned long Instruction; 174 #endif 175 176 177 178 /* 179 ** Maximum length for short strings, that is, strings that are 180 ** internalized. (Cannot be smaller than reserved words or tags for 181 ** metamethods, as these strings must be internalized; 182 ** #("function") = 8, #("__newindex") = 10.) 183 */ 184 #if !defined(LUAI_MAXSHORTLEN) 185 #define LUAI_MAXSHORTLEN 40 186 #endif 187 188 189 /* 190 ** Initial size for the string table (must be power of 2). 191 ** The Lua core alone registers ~50 strings (reserved words + 192 ** metaevent keys + a few others). Libraries would typically add 193 ** a few dozens more. 194 */ 195 #if !defined(MINSTRTABSIZE) 196 #define MINSTRTABSIZE 128 197 #endif 198 199 200 /* 201 ** Size of cache for strings in the API. 'N' is the number of 202 ** sets (better be a prime) and "M" is the size of each set (M == 1 203 ** makes a direct cache.) 204 */ 205 #if !defined(STRCACHE_N) 206 #define STRCACHE_N 53 207 #define STRCACHE_M 2 208 #endif 209 210 211 /* minimum size for string buffer */ 212 #if !defined(LUA_MINBUFFER) 213 #define LUA_MINBUFFER 32 214 #endif 215 216 217 /* 218 ** macros that are executed whenever program enters the Lua core 219 ** ('lua_lock') and leaves the core ('lua_unlock') 220 */ 221 #if !defined(lua_lock) 222 #define lua_lock(L) ((void) 0) 223 #define lua_unlock(L) ((void) 0) 224 #endif 225 226 /* 227 ** macro executed during Lua functions at points where the 228 ** function can yield. 229 */ 230 #if !defined(luai_threadyield) 231 #define luai_threadyield(L) {lua_unlock(L); lua_lock(L);} 232 #endif 233 234 235 /* 236 ** these macros allow user-specific actions on threads when you defined 237 ** LUAI_EXTRASPACE and need to do something extra when a thread is 238 ** created/deleted/resumed/yielded. 239 */ 240 #if !defined(luai_userstateopen) 241 #define luai_userstateopen(L) ((void)L) 242 #endif 243 244 #if !defined(luai_userstateclose) 245 #define luai_userstateclose(L) ((void)L) 246 #endif 247 248 #if !defined(luai_userstatethread) 249 #define luai_userstatethread(L,L1) ((void)L) 250 #endif 251 252 #if !defined(luai_userstatefree) 253 #define luai_userstatefree(L,L1) ((void)L) 254 #endif 255 256 #if !defined(luai_userstateresume) 257 #define luai_userstateresume(L,n) ((void)L) 258 #endif 259 260 #if !defined(luai_userstateyield) 261 #define luai_userstateyield(L,n) ((void)L) 262 #endif 263 264 265 266 /* 267 ** The luai_num* macros define the primitive operations over numbers. 268 */ 269 270 /* floor division (defined as 'floor(a/b)') */ 271 #if !defined(luai_numidiv) 272 #define luai_numidiv(L,a,b) ((void)L, l_floor(luai_numdiv(L,a,b))) 273 #endif 274 275 /* float division */ 276 #if !defined(luai_numdiv) 277 #define luai_numdiv(L,a,b) ((a)/(b)) 278 #endif 279 280 /* 281 ** modulo: defined as 'a - floor(a/b)*b'; this definition gives NaN when 282 ** 'b' is huge, but the result should be 'a'. 'fmod' gives the result of 283 ** 'a - trunc(a/b)*b', and therefore must be corrected when 'trunc(a/b) 284 ** ~= floor(a/b)'. That happens when the division has a non-integer 285 ** negative result, which is equivalent to the test below. 286 */ 287 #if !defined(luai_nummod) 288 #define luai_nummod(L,a,b,m) \ 289 { (m) = l_mathop(fmod)(a,b); if ((m)*(b) < 0) (m) += (b); } 290 #endif 291 292 /* exponentiation */ 293 #if !defined(luai_numpow) 294 #define luai_numpow(L,a,b) ((void)L, l_mathop(pow)(a,b)) 295 #endif 296 297 /* the others are quite standard operations */ 298 #if !defined(luai_numadd) 299 #define luai_numadd(L,a,b) ((a)+(b)) 300 #define luai_numsub(L,a,b) ((a)-(b)) 301 #define luai_nummul(L,a,b) ((a)*(b)) 302 #define luai_numunm(L,a) (-(a)) 303 #define luai_numeq(a,b) ((a)==(b)) 304 #define luai_numlt(a,b) ((a)<(b)) 305 #define luai_numle(a,b) ((a)<=(b)) 306 #define luai_numisnan(a) (!luai_numeq((a), (a))) 307 #endif 308 309 310 311 312 313 /* 314 ** macro to control inclusion of some hard tests on stack reallocation 315 */ 316 #if !defined(HARDSTACKTESTS) 317 #define condmovestack(L,pre,pos) ((void)0) 318 #else 319 /* realloc stack keeping its size */ 320 #define condmovestack(L,pre,pos) \ 321 { int sz_ = (L)->stacksize; pre; luaD_reallocstack((L), sz_); pos; } 322 #endif 323 324 #if !defined(HARDMEMTESTS) 325 #define condchangemem(L,pre,pos) ((void)0) 326 #else 327 #define condchangemem(L,pre,pos) \ 328 { if (G(L)->gcrunning) { pre; luaC_fullgc(L, 0); pos; } } 329 #endif 330 331 #endif 332