1 | /* |
2 | * Copyright (c) 2008-2020 Stefan Krah. All rights reserved. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
7 | * |
8 | * 1. Redistributions of source code must retain the above copyright |
9 | * notice, this list of conditions and the following disclaimer. |
10 | * |
11 | * 2. Redistributions in binary form must reproduce the above copyright |
12 | * notice, this list of conditions and the following disclaimer in the |
13 | * documentation and/or other materials provided with the distribution. |
14 | * |
15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND |
16 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
17 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
18 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
19 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
20 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
21 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
22 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
23 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
24 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
25 | * SUCH DAMAGE. |
26 | */ |
27 | |
28 | |
29 | #include "mpdecimal.h" |
30 | |
31 | #include <signal.h> |
32 | #include <stdio.h> |
33 | #include <string.h> |
34 | |
35 | |
36 | void |
37 | mpd_dflt_traphandler(mpd_context_t *ctx) |
38 | { |
39 | (void)ctx; |
40 | raise(SIGFPE); |
41 | } |
42 | |
43 | void (* mpd_traphandler)(mpd_context_t *) = mpd_dflt_traphandler; |
44 | |
45 | |
46 | /* Set guaranteed minimum number of coefficient words. The function may |
47 | be used once at program start. Setting MPD_MINALLOC to out-of-bounds |
48 | values is a catastrophic error, so in that case the function exits rather |
49 | than relying on the user to check a return value. */ |
50 | void |
51 | mpd_setminalloc(mpd_ssize_t n) |
52 | { |
53 | static int minalloc_is_set = 0; |
54 | |
55 | if (minalloc_is_set) { |
56 | mpd_err_warn("mpd_setminalloc: ignoring request to set " |
57 | "MPD_MINALLOC a second time\n" ); |
58 | return; |
59 | } |
60 | if (n < MPD_MINALLOC_MIN || n > MPD_MINALLOC_MAX) { |
61 | mpd_err_fatal("illegal value for MPD_MINALLOC" ); /* GCOV_NOT_REACHED */ |
62 | } |
63 | MPD_MINALLOC = n; |
64 | minalloc_is_set = 1; |
65 | } |
66 | |
67 | void |
68 | mpd_init(mpd_context_t *ctx, mpd_ssize_t prec) |
69 | { |
70 | mpd_ssize_t ideal_minalloc; |
71 | |
72 | mpd_defaultcontext(ctx); |
73 | |
74 | if (!mpd_qsetprec(ctx, prec)) { |
75 | mpd_addstatus_raise(ctx, MPD_Invalid_context); |
76 | return; |
77 | } |
78 | |
79 | ideal_minalloc = 2 * ((prec+MPD_RDIGITS-1) / MPD_RDIGITS); |
80 | if (ideal_minalloc < MPD_MINALLOC_MIN) ideal_minalloc = MPD_MINALLOC_MIN; |
81 | if (ideal_minalloc > MPD_MINALLOC_MAX) ideal_minalloc = MPD_MINALLOC_MAX; |
82 | |
83 | mpd_setminalloc(ideal_minalloc); |
84 | } |
85 | |
86 | void |
87 | mpd_maxcontext(mpd_context_t *ctx) |
88 | { |
89 | ctx->prec=MPD_MAX_PREC; |
90 | ctx->emax=MPD_MAX_EMAX; |
91 | ctx->emin=MPD_MIN_EMIN; |
92 | ctx->round=MPD_ROUND_HALF_EVEN; |
93 | ctx->traps=MPD_Traps; |
94 | ctx->status=0; |
95 | ctx->newtrap=0; |
96 | ctx->clamp=0; |
97 | ctx->allcr=1; |
98 | } |
99 | |
100 | void |
101 | mpd_defaultcontext(mpd_context_t *ctx) |
102 | { |
103 | ctx->prec=2*MPD_RDIGITS; |
104 | ctx->emax=MPD_MAX_EMAX; |
105 | ctx->emin=MPD_MIN_EMIN; |
106 | ctx->round=MPD_ROUND_HALF_UP; |
107 | ctx->traps=MPD_Traps; |
108 | ctx->status=0; |
109 | ctx->newtrap=0; |
110 | ctx->clamp=0; |
111 | ctx->allcr=1; |
112 | } |
113 | |
114 | void |
115 | mpd_basiccontext(mpd_context_t *ctx) |
116 | { |
117 | ctx->prec=9; |
118 | ctx->emax=MPD_MAX_EMAX; |
119 | ctx->emin=MPD_MIN_EMIN; |
120 | ctx->round=MPD_ROUND_HALF_UP; |
121 | ctx->traps=MPD_Traps|MPD_Clamped; |
122 | ctx->status=0; |
123 | ctx->newtrap=0; |
124 | ctx->clamp=0; |
125 | ctx->allcr=1; |
126 | } |
127 | |
128 | int |
129 | mpd_ieee_context(mpd_context_t *ctx, int bits) |
130 | { |
131 | if (bits <= 0 || bits > MPD_IEEE_CONTEXT_MAX_BITS || bits % 32) { |
132 | return -1; |
133 | } |
134 | |
135 | ctx->prec = 9 * (bits/32) - 2; |
136 | ctx->emax = 3 * ((mpd_ssize_t)1<<(bits/16+3)); |
137 | ctx->emin = 1 - ctx->emax; |
138 | ctx->round=MPD_ROUND_HALF_EVEN; |
139 | ctx->traps=0; |
140 | ctx->status=0; |
141 | ctx->newtrap=0; |
142 | ctx->clamp=1; |
143 | ctx->allcr=1; |
144 | |
145 | return 0; |
146 | } |
147 | |
148 | mpd_ssize_t |
149 | mpd_getprec(const mpd_context_t *ctx) |
150 | { |
151 | return ctx->prec; |
152 | } |
153 | |
154 | mpd_ssize_t |
155 | mpd_getemax(const mpd_context_t *ctx) |
156 | { |
157 | return ctx->emax; |
158 | } |
159 | |
160 | mpd_ssize_t |
161 | mpd_getemin(const mpd_context_t *ctx) |
162 | { |
163 | return ctx->emin; |
164 | } |
165 | |
166 | int |
167 | mpd_getround(const mpd_context_t *ctx) |
168 | { |
169 | return ctx->round; |
170 | } |
171 | |
172 | uint32_t |
173 | mpd_gettraps(const mpd_context_t *ctx) |
174 | { |
175 | return ctx->traps; |
176 | } |
177 | |
178 | uint32_t |
179 | mpd_getstatus(const mpd_context_t *ctx) |
180 | { |
181 | return ctx->status; |
182 | } |
183 | |
184 | int |
185 | mpd_getclamp(const mpd_context_t *ctx) |
186 | { |
187 | return ctx->clamp; |
188 | } |
189 | |
190 | int |
191 | mpd_getcr(const mpd_context_t *ctx) |
192 | { |
193 | return ctx->allcr; |
194 | } |
195 | |
196 | |
197 | int |
198 | mpd_qsetprec(mpd_context_t *ctx, mpd_ssize_t prec) |
199 | { |
200 | if (prec <= 0 || prec > MPD_MAX_PREC) { |
201 | return 0; |
202 | } |
203 | ctx->prec = prec; |
204 | return 1; |
205 | } |
206 | |
207 | int |
208 | mpd_qsetemax(mpd_context_t *ctx, mpd_ssize_t emax) |
209 | { |
210 | if (emax < 0 || emax > MPD_MAX_EMAX) { |
211 | return 0; |
212 | } |
213 | ctx->emax = emax; |
214 | return 1; |
215 | } |
216 | |
217 | int |
218 | mpd_qsetemin(mpd_context_t *ctx, mpd_ssize_t emin) |
219 | { |
220 | if (emin > 0 || emin < MPD_MIN_EMIN) { |
221 | return 0; |
222 | } |
223 | ctx->emin = emin; |
224 | return 1; |
225 | } |
226 | |
227 | int |
228 | mpd_qsetround(mpd_context_t *ctx, int round) |
229 | { |
230 | if (!(0 <= round && round < MPD_ROUND_GUARD)) { |
231 | return 0; |
232 | } |
233 | ctx->round = round; |
234 | return 1; |
235 | } |
236 | |
237 | int |
238 | mpd_qsettraps(mpd_context_t *ctx, uint32_t flags) |
239 | { |
240 | if (flags > MPD_Max_status) { |
241 | return 0; |
242 | } |
243 | ctx->traps = flags; |
244 | return 1; |
245 | } |
246 | |
247 | int |
248 | mpd_qsetstatus(mpd_context_t *ctx, uint32_t flags) |
249 | { |
250 | if (flags > MPD_Max_status) { |
251 | return 0; |
252 | } |
253 | ctx->status = flags; |
254 | return 1; |
255 | } |
256 | |
257 | int |
258 | mpd_qsetclamp(mpd_context_t *ctx, int c) |
259 | { |
260 | if (c != 0 && c != 1) { |
261 | return 0; |
262 | } |
263 | ctx->clamp = c; |
264 | return 1; |
265 | } |
266 | |
267 | int |
268 | mpd_qsetcr(mpd_context_t *ctx, int c) |
269 | { |
270 | if (c != 0 && c != 1) { |
271 | return 0; |
272 | } |
273 | ctx->allcr = c; |
274 | return 1; |
275 | } |
276 | |
277 | |
278 | void |
279 | mpd_addstatus_raise(mpd_context_t *ctx, uint32_t flags) |
280 | { |
281 | ctx->status |= flags; |
282 | if (flags&ctx->traps) { |
283 | ctx->newtrap = (flags&ctx->traps); |
284 | mpd_traphandler(ctx); |
285 | } |
286 | } |
287 | |