1 /* $NetBSD: libm.c,v 1.2 2022/11/23 18:15:43 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2022 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Phillip Rulon
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: libm.c,v 1.2 2022/11/23 18:15:43 christos Exp $");
33
34 #include <lua.h>
35 #include <lauxlib.h>
36 #include <math.h>
37
38 const char badarg[] = "argument to libm function not a number";
39
40 /*-
41 * The majority of libm functions fall into a few forms:
42 *
43 * int func(double);
44 * double func(double);
45 * double func(double, double);
46 * and,
47 * double func(int, double);
48 *
49 * Accordingly, this lends itself to systematic declaration of the lua
50 * interface functions. These macros set this up.
51 */
52 #define BFUNC_DBL(fname) \
53 static int \
54 libm_##fname(lua_State *L) \
55 { \
56 if (!lua_isnumber(L, 1)) \
57 return luaL_error(L, badarg); \
58 \
59 double x = lua_tonumber(L, 1); \
60 lua_pushboolean(L, fname(x)); \
61 return 1; \
62 }
63
64 #define DFUNC_DBL(fname) \
65 static int \
66 libm_##fname(lua_State *L) \
67 { \
68 if (!lua_isnumber(L, 1)) \
69 return luaL_error(L, badarg); \
70 \
71 double x = lua_tonumber(L, 1); \
72 lua_pushnumber(L, fname(x)); \
73 return 1; \
74 }
75
76 #define DFUNC_INT_DBL(fname) \
77 static int \
78 libm_##fname(lua_State *L) \
79 { \
80 if (!lua_isinteger(L, 1) || \
81 !lua_isnumber(L, 2)) \
82 return luaL_error(L, badarg); \
83 \
84 int i = (int)lua_tointeger(L, 1); \
85 double x = lua_tonumber(L, 2); \
86 lua_pushnumber(L, fname(i, x)); \
87 return 1; \
88 }
89
90 #define DFUNC_DBL_DBL(fname) \
91 static int \
92 libm_##fname(lua_State *L) \
93 { \
94 if (!lua_isnumber(L, 1) || \
95 !lua_isnumber(L, 2)) \
96 return luaL_error(L, badarg); \
97 double x[] = { \
98 lua_tonumber(L, 1), \
99 lua_tonumber(L,2) \
100 }; \
101 lua_pushnumber(L, fname(x[0], x[1])); \
102 return 1; \
103 }
104
105 int luaopen_libm(lua_State *);
106
107 DFUNC_DBL(acos)
DFUNC_DBL(acosh)108 DFUNC_DBL(acosh)
109 DFUNC_DBL(asin)
110 DFUNC_DBL(asinh)
111 DFUNC_DBL(atan)
112 DFUNC_DBL(atanh)
113 DFUNC_DBL_DBL(atan2)
114 DFUNC_DBL(cbrt)
115 DFUNC_DBL(ceil)
116 DFUNC_DBL_DBL(copysign)
117 DFUNC_DBL(cos)
118 DFUNC_DBL(cosh)
119 DFUNC_DBL(erf)
120 DFUNC_DBL(erfc)
121 DFUNC_DBL(exp)
122 DFUNC_DBL(exp2)
123 DFUNC_DBL(expm1)
124 DFUNC_DBL(fabs)
125 DFUNC_DBL_DBL(fdim)
126 BFUNC_DBL(finite)
127 DFUNC_DBL(floor)
128 DFUNC_DBL_DBL(fmax)
129 DFUNC_DBL_DBL(fmin)
130 DFUNC_DBL_DBL(fmod)
131 DFUNC_DBL(gamma)
132 DFUNC_DBL_DBL(hypot)
133 BFUNC_DBL(isfinite)
134 BFUNC_DBL(isnan)
135 BFUNC_DBL(isinf)
136 DFUNC_DBL(j0)
137 DFUNC_DBL(j1)
138 DFUNC_INT_DBL(jn)
139 DFUNC_DBL(lgamma)
140 DFUNC_DBL(log)
141 DFUNC_DBL(log10)
142 DFUNC_DBL(log1p)
143 #ifndef __vax__
144 DFUNC_DBL_DBL(nextafter)
145 #endif
146 DFUNC_DBL_DBL(pow)
147 DFUNC_DBL_DBL(remainder)
148 DFUNC_DBL(rint)
149 DFUNC_DBL(round)
150 DFUNC_DBL(sin)
151 DFUNC_DBL(sinh)
152 DFUNC_DBL(sqrt)
153 DFUNC_DBL(tan)
154 DFUNC_DBL(tanh)
155 DFUNC_DBL(trunc)
156 DFUNC_DBL(y0)
157 DFUNC_DBL(y1)
158 DFUNC_INT_DBL(yn)
159
160 /*
161 * The following interface functions are special cases which do not lend
162 * themseleves to the systematic declaration scheme above.
163 */
164 static int
165 libm_fma(lua_State *L)
166 {
167 if (!lua_isnumber(L, 1) ||
168 !lua_isnumber(L, 2) ||
169 !lua_isnumber(L, 3))
170 return luaL_error(L, badarg);
171
172 double x[] = {
173 lua_tonumber(L, 1),
174 lua_tonumber(L, 2),
175 lua_tonumber(L, 3)
176 };
177 lua_pushnumber(L, fma(x[0], x[1], x[2]));
178 return 1;
179 }
180
181 static int
libm_nan(lua_State * L)182 libm_nan(lua_State *L)
183 {
184 if (!lua_isstring(L, 1))
185 return luaL_error(L, badarg);
186
187 const char *str = luaL_checkstring(L, 1);
188 lua_pushnumber(L, nan(str));
189 return 1;
190 }
191
192 static int
libm_scalbn(lua_State * L)193 libm_scalbn(lua_State *L)
194 {
195 if (!lua_isnumber(L, 1) || !lua_isinteger(L, 2))
196 return luaL_error(L, badarg);
197
198 double x = lua_tonumber(L, 1);
199 int i = (int)lua_tointeger(L, 2);
200 lua_pushnumber(L, scalbn(x, i));
201 return 1;
202 }
203
204 static int
libm_ilogb(lua_State * L)205 libm_ilogb(lua_State *L)
206 {
207 if (!lua_isnumber(L, 1))
208 return luaL_error(L, badarg);
209
210 double x = lua_tonumber(L, 1);
211 lua_pushinteger(L, ilogb(x));
212 return 1;
213 }
214
215 /*
216 * set up a table for the math.h constants
217 */
218 #define LIBM_CONST(K) {#K, K}
219 struct kv {
220 const char *k;
221 double v;
222 };
223
224 static const struct kv libm_const[] = {
225 LIBM_CONST(M_E),
226 LIBM_CONST(M_LOG2E),
227 LIBM_CONST(M_LOG10E),
228 LIBM_CONST(M_LN2),
229 LIBM_CONST(M_LN10),
230 LIBM_CONST(M_PI),
231 LIBM_CONST(M_PI_2),
232 LIBM_CONST(M_PI_4),
233 LIBM_CONST(M_1_PI),
234 LIBM_CONST(M_2_PI),
235 LIBM_CONST(M_2_SQRTPI),
236 LIBM_CONST(M_SQRT2),
237 LIBM_CONST(M_SQRT1_2),
238 { NULL, 0 }
239 };
240
241
242 static const struct luaL_Reg lualibm[] = {
243 { "acos", libm_acos },
244 { "acosh", libm_acosh },
245 { "asin", libm_asin },
246 { "asinh", libm_asinh },
247 { "atan", libm_atan },
248 { "atanh", libm_atanh },
249 { "atan2", libm_atan2 },
250 { "cbrt", libm_cbrt },
251 { "ceil", libm_ceil },
252 { "copysign", libm_copysign },
253 { "cos", libm_cos },
254 { "cosh", libm_cosh },
255 { "erf", libm_erf },
256 { "erfc", libm_erfc },
257 { "exp", libm_exp },
258 { "exp2", libm_exp2 },
259 { "expm1", libm_expm1 },
260 { "fabs", libm_fabs },
261 { "fdim", libm_fdim },
262 { "finite", libm_finite },
263 { "floor", libm_floor },
264 { "fma", libm_fma },
265 { "fmax", libm_fmax },
266 { "fmin", libm_fmin },
267 { "fmod", libm_fmod },
268 { "gamma", libm_gamma },
269 { "hypot", libm_hypot },
270 { "ilogb", libm_ilogb },
271 { "isfinite", libm_isfinite },
272 { "isinf", libm_isinf },
273 { "isnan", libm_isnan },
274 { "j0", libm_j0 },
275 { "j1", libm_j1 },
276 { "jn", libm_jn },
277 { "lgamma", libm_lgamma },
278 { "log", libm_log },
279 { "log10", libm_log10 },
280 { "log1p", libm_log1p },
281 { "nan", libm_nan },
282 #ifndef __vax__
283 { "nextafter", libm_nextafter },
284 #endif
285 { "pow", libm_pow },
286 { "remainder", libm_remainder },
287 { "rint", libm_rint },
288 { "round", libm_round },
289 { "scalbn", libm_scalbn },
290 { "sin", libm_sin },
291 { "sinh", libm_sinh },
292 { "sqrt", libm_sqrt },
293 { "tan", libm_tan },
294 { "tanh", libm_tanh },
295 { "trunc", libm_trunc },
296 { "y0", libm_y0 },
297 { "y1", libm_y1 },
298 { "yn", libm_yn },
299 { NULL, NULL }
300 };
301
302 int
luaopen_libm(lua_State * L)303 luaopen_libm(lua_State *L)
304 {
305 const struct kv *kvp = libm_const;
306
307 luaL_newlib(L, lualibm);
308
309 /* integrate the math.h constants */
310 while (kvp->k) {
311 lua_pushnumber(L, kvp->v);
312 lua_setfield(L, -2, kvp->k);
313 kvp++;
314 }
315
316 return 1;
317 }
318