mudgangster

Tiny, scriptable MUD client
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lmathlib.cc (9916B)


      1 /*
      2 ** $Id: lmathlib.c,v 1.119.1.1 2017/04/19 17:20:42 roberto Exp $
      3 ** Standard mathematical library
      4 ** See Copyright Notice in lua.h
      5 */
      6 
      7 #define lmathlib_c
      8 #define LUA_LIB
      9 
     10 #include "lprefix.h"
     11 
     12 
     13 #include <stdlib.h>
     14 #include <math.h>
     15 
     16 #include "lua.h"
     17 
     18 #include "lauxlib.h"
     19 #include "lualib.h"
     20 
     21 
     22 #undef PI
     23 #define PI	(l_mathop(3.141592653589793238462643383279502884))
     24 
     25 
     26 #if !defined(l_rand)		/* { */
     27 #if defined(LUA_USE_POSIX)
     28 #define l_rand()	random()
     29 #define l_srand(x)	srandom(x)
     30 #define L_RANDMAX	2147483647	/* (2^31 - 1), following POSIX */
     31 #else
     32 #define l_rand()	rand()
     33 #define l_srand(x)	srand(x)
     34 #define L_RANDMAX	RAND_MAX
     35 #endif
     36 #endif				/* } */
     37 
     38 
     39 static int math_abs (lua_State *L) {
     40   if (lua_isinteger(L, 1)) {
     41     lua_Integer n = lua_tointeger(L, 1);
     42     if (n < 0) n = (lua_Integer)(0u - (lua_Unsigned)n);
     43     lua_pushinteger(L, n);
     44   }
     45   else
     46     lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
     47   return 1;
     48 }
     49 
     50 static int math_sin (lua_State *L) {
     51   lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
     52   return 1;
     53 }
     54 
     55 static int math_cos (lua_State *L) {
     56   lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
     57   return 1;
     58 }
     59 
     60 static int math_tan (lua_State *L) {
     61   lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
     62   return 1;
     63 }
     64 
     65 static int math_asin (lua_State *L) {
     66   lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
     67   return 1;
     68 }
     69 
     70 static int math_acos (lua_State *L) {
     71   lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
     72   return 1;
     73 }
     74 
     75 static int math_atan (lua_State *L) {
     76   lua_Number y = luaL_checknumber(L, 1);
     77   lua_Number x = luaL_optnumber(L, 2, 1);
     78   lua_pushnumber(L, l_mathop(atan2)(y, x));
     79   return 1;
     80 }
     81 
     82 
     83 static int math_toint (lua_State *L) {
     84   int valid;
     85   lua_Integer n = lua_tointegerx(L, 1, &valid);
     86   if (valid)
     87     lua_pushinteger(L, n);
     88   else {
     89     luaL_checkany(L, 1);
     90     lua_pushnil(L);  /* value is not convertible to integer */
     91   }
     92   return 1;
     93 }
     94 
     95 
     96 static void pushnumint (lua_State *L, lua_Number d) {
     97   lua_Integer n;
     98   if (lua_numbertointeger(d, &n))  /* does 'd' fit in an integer? */
     99     lua_pushinteger(L, n);  /* result is integer */
    100   else
    101     lua_pushnumber(L, d);  /* result is float */
    102 }
    103 
    104 
    105 static int math_floor (lua_State *L) {
    106   if (lua_isinteger(L, 1))
    107     lua_settop(L, 1);  /* integer is its own floor */
    108   else {
    109     lua_Number d = l_mathop(floor)(luaL_checknumber(L, 1));
    110     pushnumint(L, d);
    111   }
    112   return 1;
    113 }
    114 
    115 
    116 static int math_ceil (lua_State *L) {
    117   if (lua_isinteger(L, 1))
    118     lua_settop(L, 1);  /* integer is its own ceil */
    119   else {
    120     lua_Number d = l_mathop(ceil)(luaL_checknumber(L, 1));
    121     pushnumint(L, d);
    122   }
    123   return 1;
    124 }
    125 
    126 
    127 static int math_fmod (lua_State *L) {
    128   if (lua_isinteger(L, 1) && lua_isinteger(L, 2)) {
    129     lua_Integer d = lua_tointeger(L, 2);
    130     if ((lua_Unsigned)d + 1u <= 1u) {  /* special cases: -1 or 0 */
    131       luaL_argcheck(L, d != 0, 2, "zero");
    132       lua_pushinteger(L, 0);  /* avoid overflow with 0x80000... / -1 */
    133     }
    134     else
    135       lua_pushinteger(L, lua_tointeger(L, 1) % d);
    136   }
    137   else
    138     lua_pushnumber(L, l_mathop(fmod)(luaL_checknumber(L, 1),
    139                                      luaL_checknumber(L, 2)));
    140   return 1;
    141 }
    142 
    143 
    144 /*
    145 ** next function does not use 'modf', avoiding problems with 'double*'
    146 ** (which is not compatible with 'float*') when lua_Number is not
    147 ** 'double'.
    148 */
    149 static int math_modf (lua_State *L) {
    150   if (lua_isinteger(L ,1)) {
    151     lua_settop(L, 1);  /* number is its own integer part */
    152     lua_pushnumber(L, 0);  /* no fractional part */
    153   }
    154   else {
    155     lua_Number n = luaL_checknumber(L, 1);
    156     /* integer part (rounds toward zero) */
    157     lua_Number ip = (n < 0) ? l_mathop(ceil)(n) : l_mathop(floor)(n);
    158     pushnumint(L, ip);
    159     /* fractional part (test needed for inf/-inf) */
    160     lua_pushnumber(L, (n == ip) ? l_mathop(0.0) : (n - ip));
    161   }
    162   return 2;
    163 }
    164 
    165 
    166 static int math_sqrt (lua_State *L) {
    167   lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
    168   return 1;
    169 }
    170 
    171 
    172 static int math_ult (lua_State *L) {
    173   lua_Integer a = luaL_checkinteger(L, 1);
    174   lua_Integer b = luaL_checkinteger(L, 2);
    175   lua_pushboolean(L, (lua_Unsigned)a < (lua_Unsigned)b);
    176   return 1;
    177 }
    178 
    179 static int math_log (lua_State *L) {
    180   lua_Number x = luaL_checknumber(L, 1);
    181   lua_Number res;
    182   if (lua_isnoneornil(L, 2))
    183     res = l_mathop(log)(x);
    184   else {
    185     lua_Number base = luaL_checknumber(L, 2);
    186 #if !defined(LUA_USE_C89)
    187     if (base == l_mathop(2.0))
    188       res = l_mathop(log2)(x); else
    189 #endif
    190     if (base == l_mathop(10.0))
    191       res = l_mathop(log10)(x);
    192     else
    193       res = l_mathop(log)(x)/l_mathop(log)(base);
    194   }
    195   lua_pushnumber(L, res);
    196   return 1;
    197 }
    198 
    199 static int math_exp (lua_State *L) {
    200   lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
    201   return 1;
    202 }
    203 
    204 static int math_deg (lua_State *L) {
    205   lua_pushnumber(L, luaL_checknumber(L, 1) * (l_mathop(180.0) / PI));
    206   return 1;
    207 }
    208 
    209 static int math_rad (lua_State *L) {
    210   lua_pushnumber(L, luaL_checknumber(L, 1) * (PI / l_mathop(180.0)));
    211   return 1;
    212 }
    213 
    214 
    215 static int math_min (lua_State *L) {
    216   int n = lua_gettop(L);  /* number of arguments */
    217   int imin = 1;  /* index of current minimum value */
    218   int i;
    219   luaL_argcheck(L, n >= 1, 1, "value expected");
    220   for (i = 2; i <= n; i++) {
    221     if (lua_compare(L, i, imin, LUA_OPLT))
    222       imin = i;
    223   }
    224   lua_pushvalue(L, imin);
    225   return 1;
    226 }
    227 
    228 
    229 static int math_max (lua_State *L) {
    230   int n = lua_gettop(L);  /* number of arguments */
    231   int imax = 1;  /* index of current maximum value */
    232   int i;
    233   luaL_argcheck(L, n >= 1, 1, "value expected");
    234   for (i = 2; i <= n; i++) {
    235     if (lua_compare(L, imax, i, LUA_OPLT))
    236       imax = i;
    237   }
    238   lua_pushvalue(L, imax);
    239   return 1;
    240 }
    241 
    242 /*
    243 ** This function uses 'double' (instead of 'lua_Number') to ensure that
    244 ** all bits from 'l_rand' can be represented, and that 'RANDMAX + 1.0'
    245 ** will keep full precision (ensuring that 'r' is always less than 1.0.)
    246 */
    247 static int math_random (lua_State *L) {
    248   lua_Integer low, up;
    249   double r = (double)l_rand() * (1.0 / ((double)L_RANDMAX + 1.0));
    250   switch (lua_gettop(L)) {  /* check number of arguments */
    251     case 0: {  /* no arguments */
    252       lua_pushnumber(L, (lua_Number)r);  /* Number between 0 and 1 */
    253       return 1;
    254     }
    255     case 1: {  /* only upper limit */
    256       low = 1;
    257       up = luaL_checkinteger(L, 1);
    258       break;
    259     }
    260     case 2: {  /* lower and upper limits */
    261       low = luaL_checkinteger(L, 1);
    262       up = luaL_checkinteger(L, 2);
    263       break;
    264     }
    265     default: return luaL_error(L, "wrong number of arguments");
    266   }
    267   /* random integer in the interval [low, up] */
    268   luaL_argcheck(L, low <= up, 1, "interval is empty");
    269   luaL_argcheck(L, low >= 0 || up <= LUA_MAXINTEGER + low, 1,
    270                    "interval too large");
    271   r *= (double)(up - low) + 1.0;
    272   lua_pushinteger(L, (lua_Integer)r + low);
    273   return 1;
    274 }
    275 
    276 
    277 static int math_randomseed (lua_State *L) {
    278   l_srand((unsigned int)(lua_Integer)luaL_checknumber(L, 1));
    279   (void)l_rand(); /* discard first value to avoid undesirable correlations */
    280   return 0;
    281 }
    282 
    283 
    284 static int math_type (lua_State *L) {
    285   if (lua_type(L, 1) == LUA_TNUMBER) {
    286       if (lua_isinteger(L, 1))
    287         lua_pushliteral(L, "integer");
    288       else
    289         lua_pushliteral(L, "float");
    290   }
    291   else {
    292     luaL_checkany(L, 1);
    293     lua_pushnil(L);
    294   }
    295   return 1;
    296 }
    297 
    298 
    299 /*
    300 ** {==================================================================
    301 ** Deprecated functions (for compatibility only)
    302 ** ===================================================================
    303 */
    304 #if defined(LUA_COMPAT_MATHLIB)
    305 
    306 static int math_cosh (lua_State *L) {
    307   lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
    308   return 1;
    309 }
    310 
    311 static int math_sinh (lua_State *L) {
    312   lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
    313   return 1;
    314 }
    315 
    316 static int math_tanh (lua_State *L) {
    317   lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
    318   return 1;
    319 }
    320 
    321 static int math_pow (lua_State *L) {
    322   lua_Number x = luaL_checknumber(L, 1);
    323   lua_Number y = luaL_checknumber(L, 2);
    324   lua_pushnumber(L, l_mathop(pow)(x, y));
    325   return 1;
    326 }
    327 
    328 static int math_frexp (lua_State *L) {
    329   int e;
    330   lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
    331   lua_pushinteger(L, e);
    332   return 2;
    333 }
    334 
    335 static int math_ldexp (lua_State *L) {
    336   lua_Number x = luaL_checknumber(L, 1);
    337   int ep = (int)luaL_checkinteger(L, 2);
    338   lua_pushnumber(L, l_mathop(ldexp)(x, ep));
    339   return 1;
    340 }
    341 
    342 static int math_log10 (lua_State *L) {
    343   lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
    344   return 1;
    345 }
    346 
    347 #endif
    348 /* }================================================================== */
    349 
    350 
    351 
    352 static const luaL_Reg mathlib[] = {
    353   {"abs",   math_abs},
    354   {"acos",  math_acos},
    355   {"asin",  math_asin},
    356   {"atan",  math_atan},
    357   {"ceil",  math_ceil},
    358   {"cos",   math_cos},
    359   {"deg",   math_deg},
    360   {"exp",   math_exp},
    361   {"tointeger", math_toint},
    362   {"floor", math_floor},
    363   {"fmod",   math_fmod},
    364   {"ult",   math_ult},
    365   {"log",   math_log},
    366   {"max",   math_max},
    367   {"min",   math_min},
    368   {"modf",   math_modf},
    369   {"rad",   math_rad},
    370   {"random",     math_random},
    371   {"randomseed", math_randomseed},
    372   {"sin",   math_sin},
    373   {"sqrt",  math_sqrt},
    374   {"tan",   math_tan},
    375   {"type", math_type},
    376 #if defined(LUA_COMPAT_MATHLIB)
    377   {"atan2", math_atan},
    378   {"cosh",   math_cosh},
    379   {"sinh",   math_sinh},
    380   {"tanh",   math_tanh},
    381   {"pow",   math_pow},
    382   {"frexp", math_frexp},
    383   {"ldexp", math_ldexp},
    384   {"log10", math_log10},
    385 #endif
    386   /* placeholders */
    387   {"pi", NULL},
    388   {"huge", NULL},
    389   {"maxinteger", NULL},
    390   {"mininteger", NULL},
    391   {NULL, NULL}
    392 };
    393 
    394 
    395 /*
    396 ** Open math library
    397 */
    398 LUAMOD_API int luaopen_math (lua_State *L) {
    399   luaL_newlib(L, mathlib);
    400   lua_pushnumber(L, PI);
    401   lua_setfield(L, -2, "pi");
    402   lua_pushnumber(L, (lua_Number)HUGE_VAL);
    403   lua_setfield(L, -2, "huge");
    404   lua_pushinteger(L, LUA_MAXINTEGER);
    405   lua_setfield(L, -2, "maxinteger");
    406   lua_pushinteger(L, LUA_MININTEGER);
    407   lua_setfield(L, -2, "mininteger");
    408   return 1;
    409 }
    410