1 /* $NetBSD: lmathlib.c,v 1.11 2023/06/08 21:12:08 nikita Exp $ */
2
3 /*
4 ** Id: lmathlib.c
5 ** Standard mathematical library
6 ** See Copyright Notice in lua.h
7 */
8
9 #define lmathlib_c
10 #define LUA_LIB
11
12 #include "lprefix.h"
13
14
15 #include <float.h>
16 #include <limits.h>
17 #include <math.h>
18 #include <stdlib.h>
19 #include <time.h>
20
21 #include "lua.h"
22
23 #include "lauxlib.h"
24 #include "lualib.h"
25
26
27 #undef PI
28 #define PI (l_mathop(3.141592653589793238462643383279502884))
29
30
math_abs(lua_State * L)31 static int math_abs (lua_State *L) {
32 if (lua_isinteger(L, 1)) {
33 lua_Integer n = lua_tointeger(L, 1);
34 if (n < 0) n = (lua_Integer)(0u - (lua_Unsigned)n);
35 lua_pushinteger(L, n);
36 }
37 else
38 lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
39 return 1;
40 }
41
math_sin(lua_State * L)42 static int math_sin (lua_State *L) {
43 lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
44 return 1;
45 }
46
math_cos(lua_State * L)47 static int math_cos (lua_State *L) {
48 lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
49 return 1;
50 }
51
math_tan(lua_State * L)52 static int math_tan (lua_State *L) {
53 lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
54 return 1;
55 }
56
math_asin(lua_State * L)57 static int math_asin (lua_State *L) {
58 lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
59 return 1;
60 }
61
math_acos(lua_State * L)62 static int math_acos (lua_State *L) {
63 lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
64 return 1;
65 }
66
math_atan(lua_State * L)67 static int math_atan (lua_State *L) {
68 lua_Number y = luaL_checknumber(L, 1);
69 lua_Number x = luaL_optnumber(L, 2, 1);
70 lua_pushnumber(L, l_mathop(atan2)(y, x));
71 return 1;
72 }
73
74
math_toint(lua_State * L)75 static int math_toint (lua_State *L) {
76 int valid;
77 lua_Integer n = lua_tointegerx(L, 1, &valid);
78 if (l_likely(valid))
79 lua_pushinteger(L, n);
80 else {
81 luaL_checkany(L, 1);
82 luaL_pushfail(L); /* value is not convertible to integer */
83 }
84 return 1;
85 }
86
87
pushnumint(lua_State * L,lua_Number d)88 static void pushnumint (lua_State *L, lua_Number d) {
89 lua_Integer n;
90 if (lua_numbertointeger(d, &n)) /* does 'd' fit in an integer? */
91 lua_pushinteger(L, n); /* result is integer */
92 else
93 lua_pushnumber(L, d); /* result is float */
94 }
95
96
math_floor(lua_State * L)97 static int math_floor (lua_State *L) {
98 if (lua_isinteger(L, 1))
99 lua_settop(L, 1); /* integer is its own floor */
100 else {
101 lua_Number d = l_mathop(floor)(luaL_checknumber(L, 1));
102 pushnumint(L, d);
103 }
104 return 1;
105 }
106
107
math_ceil(lua_State * L)108 static int math_ceil (lua_State *L) {
109 if (lua_isinteger(L, 1))
110 lua_settop(L, 1); /* integer is its own ceil */
111 else {
112 lua_Number d = l_mathop(ceil)(luaL_checknumber(L, 1));
113 pushnumint(L, d);
114 }
115 return 1;
116 }
117
118
math_fmod(lua_State * L)119 static int math_fmod (lua_State *L) {
120 if (lua_isinteger(L, 1) && lua_isinteger(L, 2)) {
121 lua_Integer d = lua_tointeger(L, 2);
122 if ((lua_Unsigned)d + 1u <= 1u) { /* special cases: -1 or 0 */
123 luaL_argcheck(L, d != 0, 2, "zero");
124 lua_pushinteger(L, 0); /* avoid overflow with 0x80000... / -1 */
125 }
126 else
127 lua_pushinteger(L, lua_tointeger(L, 1) % d);
128 }
129 else
130 lua_pushnumber(L, l_mathop(fmod)(luaL_checknumber(L, 1),
131 luaL_checknumber(L, 2)));
132 return 1;
133 }
134
135
136 /*
137 ** next function does not use 'modf', avoiding problems with 'double*'
138 ** (which is not compatible with 'float*') when lua_Number is not
139 ** 'double'.
140 */
math_modf(lua_State * L)141 static int math_modf (lua_State *L) {
142 if (lua_isinteger(L ,1)) {
143 lua_settop(L, 1); /* number is its own integer part */
144 lua_pushnumber(L, 0); /* no fractional part */
145 }
146 else {
147 lua_Number n = luaL_checknumber(L, 1);
148 /* integer part (rounds toward zero) */
149 lua_Number ip = (n < 0) ? l_mathop(ceil)(n) : l_mathop(floor)(n);
150 pushnumint(L, ip);
151 /* fractional part (test needed for inf/-inf) */
152 lua_pushnumber(L, (n == ip) ? l_mathop(0.0) : (n - ip));
153 }
154 return 2;
155 }
156
157
math_sqrt(lua_State * L)158 static int math_sqrt (lua_State *L) {
159 lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
160 return 1;
161 }
162
163
math_ult(lua_State * L)164 static int math_ult (lua_State *L) {
165 lua_Integer a = luaL_checkinteger(L, 1);
166 lua_Integer b = luaL_checkinteger(L, 2);
167 lua_pushboolean(L, (lua_Unsigned)a < (lua_Unsigned)b);
168 return 1;
169 }
170
math_log(lua_State * L)171 static int math_log (lua_State *L) {
172 lua_Number x = luaL_checknumber(L, 1);
173 lua_Number res;
174 if (lua_isnoneornil(L, 2))
175 res = l_mathop(log)(x);
176 else {
177 lua_Number base = luaL_checknumber(L, 2);
178 #if !defined(LUA_USE_C89)
179 if (base == l_mathop(2.0))
180 res = l_mathop(log2)(x);
181 else
182 #endif
183 if (base == l_mathop(10.0))
184 res = l_mathop(log10)(x);
185 else
186 res = l_mathop(log)(x)/l_mathop(log)(base);
187 }
188 lua_pushnumber(L, res);
189 return 1;
190 }
191
math_exp(lua_State * L)192 static int math_exp (lua_State *L) {
193 lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
194 return 1;
195 }
196
math_deg(lua_State * L)197 static int math_deg (lua_State *L) {
198 lua_pushnumber(L, luaL_checknumber(L, 1) * (l_mathop(180.0) / PI));
199 return 1;
200 }
201
math_rad(lua_State * L)202 static int math_rad (lua_State *L) {
203 lua_pushnumber(L, luaL_checknumber(L, 1) * (PI / l_mathop(180.0)));
204 return 1;
205 }
206
207
math_min(lua_State * L)208 static int math_min (lua_State *L) {
209 int n = lua_gettop(L); /* number of arguments */
210 int imin = 1; /* index of current minimum value */
211 int i;
212 luaL_argcheck(L, n >= 1, 1, "value expected");
213 for (i = 2; i <= n; i++) {
214 if (lua_compare(L, i, imin, LUA_OPLT))
215 imin = i;
216 }
217 lua_pushvalue(L, imin);
218 return 1;
219 }
220
221
math_max(lua_State * L)222 static int math_max (lua_State *L) {
223 int n = lua_gettop(L); /* number of arguments */
224 int imax = 1; /* index of current maximum value */
225 int i;
226 luaL_argcheck(L, n >= 1, 1, "value expected");
227 for (i = 2; i <= n; i++) {
228 if (lua_compare(L, imax, i, LUA_OPLT))
229 imax = i;
230 }
231 lua_pushvalue(L, imax);
232 return 1;
233 }
234
235
math_type(lua_State * L)236 static int math_type (lua_State *L) {
237 if (lua_type(L, 1) == LUA_TNUMBER)
238 lua_pushstring(L, (lua_isinteger(L, 1)) ? "integer" : "float");
239 else {
240 luaL_checkany(L, 1);
241 luaL_pushfail(L);
242 }
243 return 1;
244 }
245
246
247
248 /*
249 ** {==================================================================
250 ** Pseudo-Random Number Generator based on 'xoshiro256**'.
251 ** ===================================================================
252 */
253
254 /* number of binary digits in the mantissa of a float */
255 #define FIGS l_floatatt(MANT_DIG)
256
257 #if FIGS > 64
258 /* there are only 64 random bits; use them all */
259 #undef FIGS
260 #define FIGS 64
261 #endif
262
263
264 /*
265 ** LUA_RAND32 forces the use of 32-bit integers in the implementation
266 ** of the PRN generator (mainly for testing).
267 */
268 #if !defined(LUA_RAND32) && !defined(Rand64)
269
270 /* try to find an integer type with at least 64 bits */
271
272 #if ((ULONG_MAX >> 31) >> 31) >= 3
273
274 /* 'long' has at least 64 bits */
275 #define Rand64 unsigned long
276
277 #elif !defined(LUA_USE_C89) && defined(LLONG_MAX)
278
279 /* there is a 'long long' type (which must have at least 64 bits) */
280 #define Rand64 unsigned long long
281
282 #elif ((LUA_MAXUNSIGNED >> 31) >> 31) >= 3
283
284 /* 'lua_Unsigned' has at least 64 bits */
285 #define Rand64 lua_Unsigned
286
287 #endif
288
289 #endif
290
291
292 #if defined(Rand64) /* { */
293
294 /*
295 ** Standard implementation, using 64-bit integers.
296 ** If 'Rand64' has more than 64 bits, the extra bits do not interfere
297 ** with the 64 initial bits, except in a right shift. Moreover, the
298 ** final result has to discard the extra bits.
299 */
300
301 /* avoid using extra bits when needed */
302 #define trim64(x) ((x) & 0xffffffffffffffffu)
303
304
305 /* rotate left 'x' by 'n' bits */
rotl(Rand64 x,int n)306 static Rand64 rotl (Rand64 x, int n) {
307 return (x << n) | (trim64(x) >> (64 - n));
308 }
309
nextrand(Rand64 * state)310 static Rand64 nextrand (Rand64 *state) {
311 Rand64 state0 = state[0];
312 Rand64 state1 = state[1];
313 Rand64 state2 = state[2] ^ state0;
314 Rand64 state3 = state[3] ^ state1;
315 Rand64 res = rotl(state1 * 5, 7) * 9;
316 state[0] = state0 ^ state3;
317 state[1] = state1 ^ state2;
318 state[2] = state2 ^ (state1 << 17);
319 state[3] = rotl(state3, 45);
320 return res;
321 }
322
323
324 /* must take care to not shift stuff by more than 63 slots */
325
326
327 /*
328 ** Convert bits from a random integer into a float in the
329 ** interval [0,1), getting the higher FIG bits from the
330 ** random unsigned integer and converting that to a float.
331 */
332
333 /* must throw out the extra (64 - FIGS) bits */
334 #define shift64_FIG (64 - FIGS)
335
336 /* to scale to [0, 1), multiply by scaleFIG = 2^(-FIGS) */
337 #define scaleFIG (l_mathop(0.5) / ((Rand64)1 << (FIGS - 1)))
338
I2d(Rand64 x)339 static lua_Number I2d (Rand64 x) {
340 return (lua_Number)(trim64(x) >> shift64_FIG) * scaleFIG;
341 }
342
343 /* convert a 'Rand64' to a 'lua_Unsigned' */
344 #define I2UInt(x) ((lua_Unsigned)trim64(x))
345
346 /* convert a 'lua_Unsigned' to a 'Rand64' */
347 #define Int2I(x) ((Rand64)(x))
348
349
350 #else /* no 'Rand64' }{ */
351
352 /* get an integer with at least 32 bits */
353 #if LUAI_IS32INT
354 typedef unsigned int lu_int32;
355 #else
356 typedef unsigned long lu_int32;
357 #endif
358
359
360 /*
361 ** Use two 32-bit integers to represent a 64-bit quantity.
362 */
363 typedef struct Rand64 {
364 lu_int32 h; /* higher half */
365 lu_int32 l; /* lower half */
366 } Rand64;
367
368
369 /*
370 ** If 'lu_int32' has more than 32 bits, the extra bits do not interfere
371 ** with the 32 initial bits, except in a right shift and comparisons.
372 ** Moreover, the final result has to discard the extra bits.
373 */
374
375 /* avoid using extra bits when needed */
376 #define trim32(x) ((x) & 0xffffffffu)
377
378
379 /*
380 ** basic operations on 'Rand64' values
381 */
382
383 /* build a new Rand64 value */
packI(lu_int32 h,lu_int32 l)384 static Rand64 packI (lu_int32 h, lu_int32 l) {
385 Rand64 result;
386 result.h = h;
387 result.l = l;
388 return result;
389 }
390
391 /* return i << n */
Ishl(Rand64 i,int n)392 static Rand64 Ishl (Rand64 i, int n) {
393 lua_assert(n > 0 && n < 32);
394 return packI((i.h << n) | (trim32(i.l) >> (32 - n)), i.l << n);
395 }
396
397 /* i1 ^= i2 */
Ixor(Rand64 * i1,Rand64 i2)398 static void Ixor (Rand64 *i1, Rand64 i2) {
399 i1->h ^= i2.h;
400 i1->l ^= i2.l;
401 }
402
403 /* return i1 + i2 */
Iadd(Rand64 i1,Rand64 i2)404 static Rand64 Iadd (Rand64 i1, Rand64 i2) {
405 Rand64 result = packI(i1.h + i2.h, i1.l + i2.l);
406 if (trim32(result.l) < trim32(i1.l)) /* carry? */
407 result.h++;
408 return result;
409 }
410
411 /* return i * 5 */
times5(Rand64 i)412 static Rand64 times5 (Rand64 i) {
413 return Iadd(Ishl(i, 2), i); /* i * 5 == (i << 2) + i */
414 }
415
416 /* return i * 9 */
times9(Rand64 i)417 static Rand64 times9 (Rand64 i) {
418 return Iadd(Ishl(i, 3), i); /* i * 9 == (i << 3) + i */
419 }
420
421 /* return 'i' rotated left 'n' bits */
rotl(Rand64 i,int n)422 static Rand64 rotl (Rand64 i, int n) {
423 lua_assert(n > 0 && n < 32);
424 return packI((i.h << n) | (trim32(i.l) >> (32 - n)),
425 (trim32(i.h) >> (32 - n)) | (i.l << n));
426 }
427
428 /* for offsets larger than 32, rotate right by 64 - offset */
rotl1(Rand64 i,int n)429 static Rand64 rotl1 (Rand64 i, int n) {
430 lua_assert(n > 32 && n < 64);
431 n = 64 - n;
432 return packI((trim32(i.h) >> n) | (i.l << (32 - n)),
433 (i.h << (32 - n)) | (trim32(i.l) >> n));
434 }
435
436 /*
437 ** implementation of 'xoshiro256**' algorithm on 'Rand64' values
438 */
nextrand(Rand64 * state)439 static Rand64 nextrand (Rand64 *state) {
440 Rand64 res = times9(rotl(times5(state[1]), 7));
441 Rand64 t = Ishl(state[1], 17);
442 Ixor(&state[2], state[0]);
443 Ixor(&state[3], state[1]);
444 Ixor(&state[1], state[2]);
445 Ixor(&state[0], state[3]);
446 Ixor(&state[2], t);
447 state[3] = rotl1(state[3], 45);
448 return res;
449 }
450
451
452 /*
453 ** Converts a 'Rand64' into a float.
454 */
455
456 /* an unsigned 1 with proper type */
457 #define UONE ((lu_int32)1)
458
459
460 #if FIGS <= 32
461
462 /* 2^(-FIGS) */
463 #define scaleFIG (l_mathop(0.5) / (UONE << (FIGS - 1)))
464
465 /*
466 ** get up to 32 bits from higher half, shifting right to
467 ** throw out the extra bits.
468 */
I2d(Rand64 x)469 static lua_Number I2d (Rand64 x) {
470 lua_Number h = (lua_Number)(trim32(x.h) >> (32 - FIGS));
471 return h * scaleFIG;
472 }
473
474 #else /* 32 < FIGS <= 64 */
475
476 /* must take care to not shift stuff by more than 31 slots */
477
478 /* 2^(-FIGS) = 1.0 / 2^30 / 2^3 / 2^(FIGS-33) */
479 #define scaleFIG \
480 (l_mathop(1.0) / (UONE << 30) / l_mathop(8.0) / (UONE << (FIGS - 33)))
481
482 /*
483 ** use FIGS - 32 bits from lower half, throwing out the other
484 ** (32 - (FIGS - 32)) = (64 - FIGS) bits
485 */
486 #define shiftLOW (64 - FIGS)
487
488 /*
489 ** higher 32 bits go after those (FIGS - 32) bits: shiftHI = 2^(FIGS - 32)
490 */
491 #define shiftHI ((lua_Number)(UONE << (FIGS - 33)) * l_mathop(2.0))
492
493
I2d(Rand64 x)494 static lua_Number I2d (Rand64 x) {
495 lua_Number h = (lua_Number)trim32(x.h) * shiftHI;
496 lua_Number l = (lua_Number)(trim32(x.l) >> shiftLOW);
497 return (h + l) * scaleFIG;
498 }
499
500 #endif
501
502
503 /* convert a 'Rand64' to a 'lua_Unsigned' */
I2UInt(Rand64 x)504 static lua_Unsigned I2UInt (Rand64 x) {
505 return (((lua_Unsigned)trim32(x.h) << 31) << 1) | (lua_Unsigned)trim32(x.l);
506 }
507
508 /* convert a 'lua_Unsigned' to a 'Rand64' */
Int2I(lua_Unsigned n)509 static Rand64 Int2I (lua_Unsigned n) {
510 return packI((lu_int32)((n >> 31) >> 1), (lu_int32)n);
511 }
512
513 #endif /* } */
514
515
516 /*
517 ** A state uses four 'Rand64' values.
518 */
519 typedef struct {
520 Rand64 s[4];
521 } RanState;
522
523
524 /*
525 ** Project the random integer 'ran' into the interval [0, n].
526 ** Because 'ran' has 2^B possible values, the projection can only be
527 ** uniform when the size of the interval is a power of 2 (exact
528 ** division). Otherwise, to get a uniform projection into [0, n], we
529 ** first compute 'lim', the smallest Mersenne number not smaller than
530 ** 'n'. We then project 'ran' into the interval [0, lim]. If the result
531 ** is inside [0, n], we are done. Otherwise, we try with another 'ran',
532 ** until we have a result inside the interval.
533 */
project(lua_Unsigned ran,lua_Unsigned n,RanState * state)534 static lua_Unsigned project (lua_Unsigned ran, lua_Unsigned n,
535 RanState *state) {
536 if ((n & (n + 1)) == 0) /* is 'n + 1' a power of 2? */
537 return ran & n; /* no bias */
538 else {
539 lua_Unsigned lim = n;
540 /* compute the smallest (2^b - 1) not smaller than 'n' */
541 lim |= (lim >> 1);
542 lim |= (lim >> 2);
543 lim |= (lim >> 4);
544 lim |= (lim >> 8);
545 lim |= (lim >> 16);
546 #if (LUA_MAXUNSIGNED >> 31) >= 3
547 lim |= (lim >> 32); /* integer type has more than 32 bits */
548 #endif
549 lua_assert((lim & (lim + 1)) == 0 /* 'lim + 1' is a power of 2, */
550 && lim >= n /* not smaller than 'n', */
551 && (lim >> 1) < n); /* and it is the smallest one */
552 while ((ran &= lim) > n) /* project 'ran' into [0..lim] */
553 ran = I2UInt(nextrand(state->s)); /* not inside [0..n]? try again */
554 return ran;
555 }
556 }
557
558
math_random(lua_State * L)559 static int math_random (lua_State *L) {
560 lua_Integer low, up;
561 lua_Unsigned p;
562 RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
563 Rand64 rv = nextrand(state->s); /* next pseudo-random value */
564 switch (lua_gettop(L)) { /* check number of arguments */
565 case 0: { /* no arguments */
566 lua_pushnumber(L, I2d(rv)); /* float between 0 and 1 */
567 return 1;
568 }
569 case 1: { /* only upper limit */
570 low = 1;
571 up = luaL_checkinteger(L, 1);
572 if (up == 0) { /* single 0 as argument? */
573 lua_pushinteger(L, I2UInt(rv)); /* full random integer */
574 return 1;
575 }
576 break;
577 }
578 case 2: { /* lower and upper limits */
579 low = luaL_checkinteger(L, 1);
580 up = luaL_checkinteger(L, 2);
581 break;
582 }
583 default: return luaL_error(L, "wrong number of arguments");
584 }
585 /* random integer in the interval [low, up] */
586 luaL_argcheck(L, low <= up, 1, "interval is empty");
587 /* project random integer into the interval [0, up - low] */
588 p = project(I2UInt(rv), (lua_Unsigned)up - (lua_Unsigned)low, state);
589 lua_pushinteger(L, p + (lua_Unsigned)low);
590 return 1;
591 }
592
593
setseed(lua_State * L,Rand64 * state,lua_Unsigned n1,lua_Unsigned n2)594 static void setseed (lua_State *L, Rand64 *state,
595 lua_Unsigned n1, lua_Unsigned n2) {
596 int i;
597 state[0] = Int2I(n1);
598 state[1] = Int2I(0xff); /* avoid a zero state */
599 state[2] = Int2I(n2);
600 state[3] = Int2I(0);
601 for (i = 0; i < 16; i++)
602 nextrand(state); /* discard initial values to "spread" seed */
603 lua_pushinteger(L, n1);
604 lua_pushinteger(L, n2);
605 }
606
607
608 /*
609 ** Set a "random" seed. To get some randomness, use the current time
610 ** and the address of 'L' (in case the machine does address space layout
611 ** randomization).
612 */
randseed(lua_State * L,RanState * state)613 static void randseed (lua_State *L, RanState *state) {
614 lua_Unsigned seed1 = (lua_Unsigned)time(NULL);
615 lua_Unsigned seed2 = (lua_Unsigned)(size_t)L;
616 setseed(L, state->s, seed1, seed2);
617 }
618
619
math_randomseed(lua_State * L)620 static int math_randomseed (lua_State *L) {
621 RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
622 if (lua_isnone(L, 1)) {
623 randseed(L, state);
624 }
625 else {
626 lua_Integer n1 = luaL_checkinteger(L, 1);
627 lua_Integer n2 = luaL_optinteger(L, 2, 0);
628 setseed(L, state->s, n1, n2);
629 }
630 return 2; /* return seeds */
631 }
632
633
634 static const luaL_Reg randfuncs[] = {
635 {"random", math_random},
636 {"randomseed", math_randomseed},
637 {NULL, NULL}
638 };
639
640
641 /*
642 ** Register the random functions and initialize their state.
643 */
setrandfunc(lua_State * L)644 static void setrandfunc (lua_State *L) {
645 RanState *state = (RanState *)lua_newuserdatauv(L, sizeof(RanState), 0);
646 randseed(L, state); /* initialize with a "random" seed */
647 lua_pop(L, 2); /* remove pushed seeds */
648 luaL_setfuncs(L, randfuncs, 1);
649 }
650
651 /* }================================================================== */
652
653
654 /*
655 ** {==================================================================
656 ** Deprecated functions (for compatibility only)
657 ** ===================================================================
658 */
659 #if defined(LUA_COMPAT_MATHLIB)
660
math_cosh(lua_State * L)661 static int math_cosh (lua_State *L) {
662 lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
663 return 1;
664 }
665
math_sinh(lua_State * L)666 static int math_sinh (lua_State *L) {
667 lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
668 return 1;
669 }
670
math_tanh(lua_State * L)671 static int math_tanh (lua_State *L) {
672 lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
673 return 1;
674 }
675
math_pow(lua_State * L)676 static int math_pow (lua_State *L) {
677 lua_Number x = luaL_checknumber(L, 1);
678 lua_Number y = luaL_checknumber(L, 2);
679 lua_pushnumber(L, l_mathop(pow)(x, y));
680 return 1;
681 }
682
math_frexp(lua_State * L)683 static int math_frexp (lua_State *L) {
684 int e;
685 lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
686 lua_pushinteger(L, e);
687 return 2;
688 }
689
math_ldexp(lua_State * L)690 static int math_ldexp (lua_State *L) {
691 lua_Number x = luaL_checknumber(L, 1);
692 int ep = (int)luaL_checkinteger(L, 2);
693 lua_pushnumber(L, l_mathop(ldexp)(x, ep));
694 return 1;
695 }
696
math_log10(lua_State * L)697 static int math_log10 (lua_State *L) {
698 lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
699 return 1;
700 }
701
702 #endif
703 /* }================================================================== */
704
705
706
707 static const luaL_Reg mathlib[] = {
708 {"abs", math_abs},
709 {"acos", math_acos},
710 {"asin", math_asin},
711 {"atan", math_atan},
712 {"ceil", math_ceil},
713 {"cos", math_cos},
714 {"deg", math_deg},
715 {"exp", math_exp},
716 {"tointeger", math_toint},
717 {"floor", math_floor},
718 {"fmod", math_fmod},
719 {"ult", math_ult},
720 {"log", math_log},
721 {"max", math_max},
722 {"min", math_min},
723 {"modf", math_modf},
724 {"rad", math_rad},
725 {"sin", math_sin},
726 {"sqrt", math_sqrt},
727 {"tan", math_tan},
728 {"type", math_type},
729 #if defined(LUA_COMPAT_MATHLIB)
730 {"atan2", math_atan},
731 {"cosh", math_cosh},
732 {"sinh", math_sinh},
733 {"tanh", math_tanh},
734 {"pow", math_pow},
735 {"frexp", math_frexp},
736 {"ldexp", math_ldexp},
737 {"log10", math_log10},
738 #endif
739 /* placeholders */
740 {"random", NULL},
741 {"randomseed", NULL},
742 {"pi", NULL},
743 {"huge", NULL},
744 {"maxinteger", NULL},
745 {"mininteger", NULL},
746 {NULL, NULL}
747 };
748
749
750 /*
751 ** Open math library
752 */
luaopen_math(lua_State * L)753 LUAMOD_API int luaopen_math (lua_State *L) {
754 luaL_newlib(L, mathlib);
755 lua_pushnumber(L, PI);
756 lua_setfield(L, -2, "pi");
757 lua_pushnumber(L, (lua_Number)HUGE_VAL);
758 lua_setfield(L, -2, "huge");
759 lua_pushinteger(L, LUA_MAXINTEGER);
760 lua_setfield(L, -2, "maxinteger");
761 lua_pushinteger(L, LUA_MININTEGER);
762 lua_setfield(L, -2, "mininteger");
763 setrandfunc(L);
764 return 1;
765 }
766
767