Commit | Line | Data |
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0f5ec153 | 1 | /* -*-c-*- |
2 | * | |
581c854e | 3 | * Prime generation glue |
0f5ec153 | 4 | * |
5 | * (c) 1999 Straylight/Edgeware | |
6 | */ | |
7 | ||
45c0fd36 | 8 | /*----- Licensing notice --------------------------------------------------* |
0f5ec153 | 9 | * |
10 | * This file is part of Catacomb. | |
11 | * | |
12 | * Catacomb is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU Library General Public License as | |
14 | * published by the Free Software Foundation; either version 2 of the | |
15 | * License, or (at your option) any later version. | |
45c0fd36 | 16 | * |
0f5ec153 | 17 | * Catacomb is distributed in the hope that it will be useful, |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU Library General Public License for more details. | |
45c0fd36 | 21 | * |
0f5ec153 | 22 | * You should have received a copy of the GNU Library General Public |
23 | * License along with Catacomb; if not, write to the Free | |
24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, | |
25 | * MA 02111-1307, USA. | |
26 | */ | |
27 | ||
0f5ec153 | 28 | /*----- Header files ------------------------------------------------------*/ |
29 | ||
581c854e | 30 | #include <assert.h> |
31 | #include <stdio.h> | |
32 | #include <stdlib.h> | |
33 | #include <string.h> | |
34 | ||
35 | #include "fibrand.h" | |
36 | #include "grand.h" | |
0f5ec153 | 37 | #include "mp.h" |
581c854e | 38 | #include "mprand.h" |
0f5ec153 | 39 | #include "pgen.h" |
581c854e | 40 | #include "pfilt.h" |
0f5ec153 | 41 | #include "rabin.h" |
42 | ||
581c854e | 43 | /*----- Standard prime filter ---------------------------------------------*/ |
0f5ec153 | 44 | |
581c854e | 45 | /* --- @pgen_filter@ --- */ |
0f5ec153 | 46 | |
581c854e | 47 | int pgen_filter(int rq, pgen_event *ev, void *p) |
0f5ec153 | 48 | { |
581c854e | 49 | pgen_filterctx *f = p; |
57541e97 | 50 | int rc = PGEN_FAIL; |
581c854e | 51 | |
52 | switch (rq) { | |
53 | case PGEN_BEGIN: | |
54 | rc = pfilt_create(&f->f, ev->m); | |
55 | mp_drop(ev->m); | |
56 | break; | |
57 | case PGEN_TRY: | |
58 | mp_drop(ev->m); | |
581c854e | 59 | break; |
60 | case PGEN_DONE: | |
61 | pfilt_destroy(&f->f); | |
62 | return (PGEN_DONE); | |
57541e97 | 63 | default: |
64 | rc = PGEN_ABORT; | |
65 | break; | |
0f5ec153 | 66 | } |
45c0fd36 | 67 | |
57541e97 | 68 | if (rc == PGEN_FAIL && !((f->step | f->f.m->v[0]) & 1)) |
69 | rc = pfilt_step(&f->f, 1); | |
581c854e | 70 | while (rc == PGEN_FAIL) |
71 | rc = pfilt_step(&f->f, f->step); | |
72 | ev->m = MP_COPY(f->f.m); | |
0f5ec153 | 73 | return (rc); |
74 | } | |
75 | ||
581c854e | 76 | /* --- @pgen_jump@ --- * |
0f5ec153 | 77 | * |
581c854e | 78 | * Similar to the standard @pgen_filter@, but jumps in large steps rather |
79 | * than small ones. | |
0f5ec153 | 80 | */ |
81 | ||
581c854e | 82 | int pgen_jump(int rq, pgen_event *ev, void *p) |
0f5ec153 | 83 | { |
581c854e | 84 | pgen_jumpctx *f = p; |
85 | int rc = PGEN_ABORT; | |
0f5ec153 | 86 | |
581c854e | 87 | switch (rq) { |
8b021c3f | 88 | case PGEN_BEGIN: { |
89 | mp *g = MP_NEW; | |
90 | mp_gcd(&g, 0, 0, ev->m, f->j->m); | |
91 | if (MP_CMP(g, >, MP_ONE)) { | |
92 | mp_drop(g); | |
93 | return (PGEN_ABORT); | |
94 | } | |
95 | mp_drop(g); | |
581c854e | 96 | rc = pfilt_create(&f->f, ev->m); |
97 | mp_drop(ev->m); | |
8b021c3f | 98 | } break; |
581c854e | 99 | case PGEN_TRY: |
100 | mp_drop(ev->m); | |
101 | rc = pfilt_jump(&f->f, f->j); | |
102 | break; | |
103 | case PGEN_DONE: | |
104 | pfilt_destroy(&f->f); | |
105 | return (PGEN_DONE); | |
106 | } | |
45c0fd36 | 107 | |
581c854e | 108 | while (rc == PGEN_FAIL) |
109 | rc = pfilt_jump(&f->f, f->j); | |
110 | ev->m = MP_COPY(f->f.m); | |
111 | return (rc); | |
112 | } | |
0f5ec153 | 113 | |
581c854e | 114 | /*----- Standard prime test -----------------------------------------------*/ |
0f5ec153 | 115 | |
581c854e | 116 | /* --- @pgen_test@ --- */ |
0f5ec153 | 117 | |
581c854e | 118 | int pgen_test(int rq, pgen_event *ev, void *p) |
119 | { | |
120 | rabin *r = p; | |
121 | int rc = PGEN_ABORT; | |
0f5ec153 | 122 | |
581c854e | 123 | switch (rq) { |
124 | case PGEN_BEGIN: | |
125 | rabin_create(r, ev->m); | |
126 | rc = PGEN_TRY; | |
127 | break; | |
283b9af0 | 128 | case PGEN_TRY: |
129 | if (!ev->tests) | |
130 | rc = rabin_rtest(r, MP_TWO); | |
131 | else { | |
132 | mp *a = mprand_range(MP_NEW, ev->m, ev->r, 0); | |
133 | rc = rabin_rtest(r, a); | |
134 | mp_drop(a); | |
135 | } | |
136 | break; | |
581c854e | 137 | case PGEN_DONE: |
138 | rabin_destroy(r); | |
139 | rc = PGEN_DONE; | |
140 | break; | |
0f5ec153 | 141 | } |
142 | ||
0f5ec153 | 143 | return (rc); |
144 | } | |
145 | ||
581c854e | 146 | /*----- The main driver ---------------------------------------------------*/ |
147 | ||
148 | /* --- @pgen@ --- * | |
bd98b2df | 149 | * |
581c854e | 150 | * Arguments: @const char *name@ = name of the value being searched for |
151 | * @mp *d@ = destination for the result integer | |
152 | * @mp *m@ = start value to pass to stepper | |
153 | * @pgen_proc *event@ = event handler function | |
154 | * @void *ectx@ = context argument for event andler | |
155 | * @unsigned steps@ = number of steps to take in search | |
156 | * @pgen_proc *step@ = stepper function to use | |
157 | * @void *sctx@ = context argument for stepper | |
158 | * @unsigned tests@ = number of tests to make | |
159 | * @pgen_proc *test@ = tester function to use | |
160 | * @void *tctx@ = context argument for tester | |
bd98b2df | 161 | * |
581c854e | 162 | * Returns: Pointer to final result, or null. |
bd98b2df | 163 | * |
581c854e | 164 | * Use: A generalized prime-number search skeleton. Yes, that's a |
165 | * scary number of arguments. | |
bd98b2df | 166 | */ |
167 | ||
581c854e | 168 | mp *pgen(const char *name, mp *d, mp *m, pgen_proc *event, void *ectx, |
169 | unsigned steps, pgen_proc *step, void *sctx, | |
170 | unsigned tests, pgen_proc *test, void *tctx) | |
bd98b2df | 171 | { |
581c854e | 172 | pgen_event ev; |
173 | int rq, rc; | |
174 | pgen_proc *proc; | |
175 | void *ctx; | |
4108c8d2 | 176 | int p; |
177 | ||
178 | enum { P_STEP, P_TEST }; | |
bd98b2df | 179 | |
581c854e | 180 | /* --- Set up the initial event block --- */ |
bd98b2df | 181 | |
581c854e | 182 | ev.name = name; |
183 | if (m) | |
184 | ev.m = MP_COPY(m); | |
185 | else | |
186 | ev.m = 0; | |
283b9af0 | 187 | ev.steps = 0; |
188 | ev.tests = 0; | |
581c854e | 189 | ev.r = fibrand_create(0); |
bd98b2df | 190 | |
581c854e | 191 | /* --- Tell the event handler we're under way --- */ |
bd98b2df | 192 | |
4108c8d2 | 193 | if (event && event(PGEN_BEGIN, &ev, ectx) == PGEN_ABORT) { |
194 | ev.r->ops->destroy(ev.r); | |
581c854e | 195 | return (0); |
4108c8d2 | 196 | } |
bd98b2df | 197 | |
581c854e | 198 | /* --- Set up for the initial call --- */ |
bd98b2df | 199 | |
4108c8d2 | 200 | proc = step; ctx = sctx; p = P_STEP; rq = PGEN_BEGIN; |
0f5ec153 | 201 | |
581c854e | 202 | /* --- Enter the great maelstrom of state transitions --- */ |
0f5ec153 | 203 | |
581c854e | 204 | for (;;) { |
205 | unsigned act = 0; | |
206 | ||
4108c8d2 | 207 | #define A_STEP 1u |
208 | #define A_TEST 2u | |
209 | #define A_EVENT 4u | |
210 | #define A_ENDTEST 8u | |
211 | #define A_ENDSTEP 16u | |
212 | #define A_DONE 32u | |
581c854e | 213 | |
214 | /* --- Call the procedure and decide what to do next --- */ | |
215 | ||
216 | rc = proc(rq, &ev, ctx); | |
217 | switch (rc) { | |
218 | case PGEN_TRY: | |
4108c8d2 | 219 | if (p == P_TEST) |
581c854e | 220 | rq = PGEN_TRY; |
221 | else { | |
222 | act |= A_EVENT; | |
4108c8d2 | 223 | proc = test; ctx = tctx; p = P_TEST; |
581c854e | 224 | rq = PGEN_BEGIN; |
225 | } | |
226 | break; | |
227 | case PGEN_PASS: | |
228 | act |= A_TEST | A_EVENT; | |
4108c8d2 | 229 | if (p == P_TEST) |
581c854e | 230 | rq = PGEN_TRY; |
231 | else { | |
4108c8d2 | 232 | proc = test; ctx = tctx; p = P_TEST; |
581c854e | 233 | rq = PGEN_BEGIN; |
234 | } | |
235 | break; | |
236 | case PGEN_FAIL: | |
237 | act |= A_STEP; | |
4108c8d2 | 238 | if (p == P_TEST) { |
581c854e | 239 | act |= A_ENDTEST | A_EVENT; |
4108c8d2 | 240 | proc = step; ctx = sctx; p = P_STEP; |
581c854e | 241 | } |
242 | rq = PGEN_TRY; | |
243 | break; | |
244 | case PGEN_DONE: | |
245 | act |= A_EVENT | A_DONE | A_ENDSTEP; | |
4108c8d2 | 246 | if (p == P_TEST) |
581c854e | 247 | act |= A_ENDTEST; |
248 | break; | |
249 | case PGEN_ABORT: | |
250 | act |= A_EVENT | A_DONE; | |
4108c8d2 | 251 | if (p == P_TEST || rq == PGEN_TRY) |
581c854e | 252 | act |= A_ENDSTEP; |
4108c8d2 | 253 | if (p == P_TEST && rq != PGEN_BEGIN) |
581c854e | 254 | act |= A_ENDTEST; |
255 | break; | |
256 | default: | |
257 | assert(((void)"Invalid response from function", 0)); | |
258 | break; | |
259 | } | |
0f5ec153 | 260 | |
581c854e | 261 | /* --- If decrementing counters is requested, do that --- */ |
0f5ec153 | 262 | |
581c854e | 263 | if ((act & A_STEP) && steps) { |
283b9af0 | 264 | ev.steps++; |
265 | if (ev.steps == steps) { | |
581c854e | 266 | act |= A_EVENT | A_ENDSTEP | A_DONE; |
267 | rc = PGEN_ABORT; | |
268 | } | |
283b9af0 | 269 | ev.tests = 0; |
581c854e | 270 | } |
0f5ec153 | 271 | |
581c854e | 272 | if ((act & A_TEST) && tests) { |
283b9af0 | 273 | ev.tests++; |
274 | if (ev.tests == tests) { | |
581c854e | 275 | act |= A_ENDTEST | A_ENDSTEP | A_DONE; |
276 | rc = PGEN_DONE; | |
277 | } | |
0f5ec153 | 278 | } |
0f5ec153 | 279 | |
581c854e | 280 | /* --- Report an event if so directed --- */ |
bd98b2df | 281 | |
581c854e | 282 | if ((act & A_EVENT) && event && event(rc, &ev, ectx) == PGEN_ABORT) { |
283 | rc = PGEN_ABORT; | |
284 | if (!(act & A_DONE)) { | |
285 | act |= A_ENDSTEP | A_DONE; | |
8501f5f0 | 286 | if (p == P_TEST && rq != PGEN_BEGIN) |
581c854e | 287 | act |= A_ENDTEST; |
288 | } | |
45c0fd36 | 289 | } |
bd98b2df | 290 | |
581c854e | 291 | /* --- Close down tester and stepper functions --- */ |
0f5ec153 | 292 | |
581c854e | 293 | if (act & A_ENDTEST) |
294 | test(PGEN_DONE, &ev, tctx); | |
295 | if (act & A_ENDSTEP) | |
296 | step(PGEN_DONE, &ev, sctx); | |
297 | ||
298 | /* --- Stop the entire test if necessary --- */ | |
299 | ||
300 | if (act & A_DONE) | |
301 | break; | |
302 | } | |
303 | ||
304 | /* --- Tidy up and return --- */ | |
305 | ||
306 | if (rc == PGEN_ABORT) { | |
307 | mp_drop(ev.m); | |
308 | ev.m = 0; | |
309 | } | |
310 | ev.r->ops->destroy(ev.r); | |
eab06f16 | 311 | mp_drop(d); |
581c854e | 312 | |
313 | return (ev.m); | |
0f5ec153 | 314 | } |
315 | ||
34e4f738 | 316 | /* --- @pgen_primep@ --- * |
317 | * | |
318 | * Arguments: @mp *p@ = a number to check | |
319 | * @grand *gr@ = a random number source | |
320 | * | |
321 | * Returns: Nonzero if @p@ is really prime. | |
6001a9ff MW |
322 | * |
323 | * Use: Checks the primality of @p@. If @p@ is prime, then this | |
324 | * function returns nonzero; if @p@ is really composite then it | |
325 | * %%\emph{probably}%% returns zero, but might not. | |
326 | * | |
327 | * Currently, this function uses the Baillie--PSW test, which | |
328 | * combines a single Miller--Rabin test with witness 2 with a | |
329 | * single Frobenius test with parameters chosen using | |
330 | * Selfridge's `Method A'. No composites are known which pass | |
331 | * this test, though it's conjectured that infinitely many | |
332 | * exist. | |
34e4f738 | 333 | */ |
334 | ||
335 | int pgen_primep(mp *p, grand *gr) | |
336 | { | |
34e4f738 | 337 | rabin r; |
6001a9ff | 338 | int rc; |
34e4f738 | 339 | |
a69a3efd | 340 | if (MP_NEGP(p)) return (0); |
34e4f738 | 341 | switch (pfilt_smallfactor(p)) { |
342 | case PGEN_DONE: return (1); | |
343 | case PGEN_FAIL: return (0); | |
344 | } | |
6001a9ff MW |
345 | rabin_create(&r, p); rc = rabin_test(&r, MP_TWO); rabin_destroy(&r); |
346 | if (rc == PGEN_FAIL) return (0); | |
347 | rc = pgen_granfrob(p, 0, 0); if (rc == PGEN_FAIL) return (0); | |
348 | return (1); | |
34e4f738 | 349 | } |
350 | ||
581c854e | 351 | /*----- Test rig ----------------------------------------------------------*/ |
0f5ec153 | 352 | |
353 | #ifdef TEST_RIG | |
354 | ||
355 | #include <mLib/testrig.h> | |
356 | ||
d31f4a79 MW |
357 | static int t_primep(dstr *v) |
358 | { | |
359 | mp *m = *(mp **)v[0].buf; | |
360 | int e = *(int *)v[1].buf; | |
361 | int r; | |
362 | grand *rng; | |
363 | int ok = 1; | |
364 | ||
365 | rng = fibrand_create(0); | |
366 | r = pgen_primep(m, rng); | |
367 | GR_DESTROY(rng); | |
368 | if (e != r) { | |
369 | fputs("\n*** primep failed", stderr); | |
370 | fputs("\nm = ", stderr); mp_writefile(m, stderr, 10); | |
371 | fprintf(stderr, "\nexpected %d", e); | |
372 | fprintf(stderr, "\nreported %d", r); | |
373 | fputc('\n', stderr); | |
374 | ok = 0; | |
375 | } | |
376 | ||
377 | mp_drop(m); | |
378 | assert(mparena_count(MPARENA_GLOBAL) == 0); | |
45c0fd36 | 379 | return (ok); |
d31f4a79 MW |
380 | } |
381 | ||
0f5ec153 | 382 | static int verify(dstr *v) |
383 | { | |
384 | mp *m = *(mp **)v[0].buf; | |
581c854e | 385 | mp *q = *(mp **)v[1].buf; |
386 | mp *p; | |
0f5ec153 | 387 | int ok = 1; |
388 | ||
581c854e | 389 | pgen_filterctx pf; |
390 | rabin r; | |
0f5ec153 | 391 | |
581c854e | 392 | pf.step = 2; |
393 | p = pgen("p", MP_NEW, m, pgen_evspin, 0, 0, pgen_filter, &pf, | |
394 | rabin_iters(mp_bits(m)), pgen_test, &r); | |
22bab86c | 395 | if (!p || !MP_EQ(p, q)) { |
581c854e | 396 | fputs("\n*** pgen failed", stderr); |
0f5ec153 | 397 | fputs("\nm = ", stderr); mp_writefile(m, stderr, 10); |
581c854e | 398 | fputs("\np = ", stderr); mp_writefile(p, stderr, 10); |
399 | fputs("\nq = ", stderr); mp_writefile(q, stderr, 10); | |
0f5ec153 | 400 | fputc('\n', stderr); |
401 | ok = 0; | |
402 | } | |
403 | ||
404 | mp_drop(m); | |
581c854e | 405 | mp_drop(q); |
eab06f16 | 406 | mp_drop(p); |
d94f85ac | 407 | assert(mparena_count(MPARENA_GLOBAL) == 0); |
0f5ec153 | 408 | return (ok); |
409 | } | |
410 | ||
411 | static test_chunk tests[] = { | |
412 | { "pgen", verify, { &type_mp, &type_mp, 0 } }, | |
d31f4a79 | 413 | { "primep", t_primep, { &type_mp, &type_int, 0 } }, |
0f5ec153 | 414 | { 0, 0, { 0 } } |
415 | }; | |
416 | ||
417 | int main(int argc, char *argv[]) | |
418 | { | |
419 | sub_init(); | |
0f00dc4c | 420 | test_run(argc, argv, tests, SRCDIR "/t/pgen"); |
0f5ec153 | 421 | return (0); |
422 | } | |
0f5ec153 | 423 | #endif |
424 | ||
425 | /*----- That's all, folks -------------------------------------------------*/ |