2 * Copyright (c) 2007-2009, Novell Inc.
4 * This program is licensed under the BSD license, read LICENSE.BSD
5 * for further information
20 #include "solver_private.h"
25 #include "solverdebug.h"
28 /**********************************************************************************/
30 /* a problem is an item on the solver's problem list. It can either be >0, in that
31 * case it is a update/infarch/dup rule, or it can be <0, which makes it refer to a job
32 * consisting of multiple job rules.
36 solver_disableproblem(Solver *solv, Id v)
44 if (v >= solv->infarchrules && v < solv->infarchrules_end)
46 Pool *pool = solv->pool;
47 Id name = pool->solvables[-solv->rules[v].p].name;
48 while (v > solv->infarchrules && pool->solvables[-solv->rules[v - 1].p].name == name)
50 for (; v < solv->infarchrules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
51 solver_disablerule(solv, solv->rules + v);
54 if (v >= solv->duprules && v < solv->duprules_end)
56 Pool *pool = solv->pool;
57 Id name = pool->solvables[-solv->rules[v].p].name;
58 while (v > solv->duprules && pool->solvables[-solv->rules[v - 1].p].name == name)
60 for (; v < solv->duprules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
61 solver_disablerule(solv, solv->rules + v);
64 solver_disablerule(solv, solv->rules + v);
66 /* XXX: doesn't work */
67 if (v >= solv->updaterules && v < solv->updaterules_end)
69 /* enable feature rule if we disabled the update rule */
70 r = solv->rules + (v - solv->updaterules + solv->featurerules);
72 solver_enablerule(solv, r);
78 jp = solv->ruletojob.elements;
79 for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++, jp++)
81 solver_disablerule(solv, r);
84 /*-------------------------------------------------------------------
89 solver_enableproblem(Solver *solv, Id v)
97 if (v >= solv->infarchrules && v < solv->infarchrules_end)
99 Pool *pool = solv->pool;
100 Id name = pool->solvables[-solv->rules[v].p].name;
101 while (v > solv->infarchrules && pool->solvables[-solv->rules[v - 1].p].name == name)
103 for (; v < solv->infarchrules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
104 solver_enablerule(solv, solv->rules + v);
107 if (v >= solv->duprules && v < solv->duprules_end)
109 Pool *pool = solv->pool;
110 Id name = pool->solvables[-solv->rules[v].p].name;
111 while (v > solv->duprules && pool->solvables[-solv->rules[v - 1].p].name == name)
113 for (; v < solv->duprules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
114 solver_enablerule(solv, solv->rules + v);
117 if (v >= solv->featurerules && v < solv->featurerules_end)
119 /* do not enable feature rule if update rule is enabled */
120 r = solv->rules + (v - solv->featurerules + solv->updaterules);
124 solver_enablerule(solv, solv->rules + v);
125 if (v >= solv->updaterules && v < solv->updaterules_end)
127 /* disable feature rule when enabling update rule */
128 r = solv->rules + (v - solv->updaterules + solv->featurerules);
130 solver_disablerule(solv, r);
135 jp = solv->ruletojob.elements;
136 for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++, jp++)
138 solver_enablerule(solv, r);
142 /*-------------------------------------------------------------------
145 * Reenable all disabled weak rules (marked in weakrulemap)
150 enableweakrules(Solver *solv)
155 for (i = 1, r = solv->rules + i; i < solv->learntrules; i++, r++)
157 if (r->d >= 0) /* already enabled? */
159 if (!MAPTST(&solv->weakrulemap, i))
161 solver_enablerule(solv, r);
166 /*-------------------------------------------------------------------
170 * at this point, all rules that led to conflicts are disabled.
171 * we re-enable all rules of a problem set but rule "sug", then
172 * continue to disable more rules until there as again a solution.
175 /* FIXME: think about conflicting assertions */
178 refine_suggestion(Solver *solv, Id *problem, Id sug, Queue *refined, int essentialok)
180 Pool *pool = solv->pool;
186 IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
188 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "refine_suggestion start\n");
189 for (i = 0; problem[i]; i++)
191 if (problem[i] == sug)
192 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "=> ");
193 solver_printproblem(solv, problem[i]);
196 queue_empty(refined);
197 if (!essentialok && sug < 0 && (solv->job.elements[-sug - 1] & SOLVER_ESSENTIAL) != 0)
199 queue_init(&disabled);
200 queue_push(refined, sug);
202 /* re-enable all problem rules with the exception of "sug"(gestion) */
205 for (i = 0; problem[i]; i++)
206 if (problem[i] != sug)
207 solver_enableproblem(solv, problem[i]);
210 solver_reenablepolicyrules(solv, -sug);
211 else if (sug >= solv->updaterules && sug < solv->updaterules_end)
213 /* enable feature rule */
214 Rule *r = solv->rules + solv->featurerules + (sug - solv->updaterules);
216 solver_enablerule(solv, r);
219 enableweakrules(solv);
223 int njob, nfeature, nupdate, pass;
224 queue_empty(&solv->problems);
227 if (!solv->problems.count)
228 solver_run_sat(solv, 0, 0);
230 if (!solv->problems.count)
232 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "no more problems!\n");
233 break; /* great, no more problems */
235 disabledcnt = disabled.count;
236 /* start with 1 to skip over proof index */
237 njob = nfeature = nupdate = 0;
238 for (pass = 0; pass < 2; pass++)
240 for (i = 1; i < solv->problems.count - 1; i++)
242 /* ignore solutions in refined */
243 v = solv->problems.elements[i];
245 break; /* end of problem reached */
248 /* check if v is in the given problems list
249 * we allow disabling all problem rules *after* sug in
250 * pass 2, to prevent getting the same solution twice */
251 for (j = 0; problem[j]; j++)
252 if (problem[j] == v || (pass && problem[j] == sug))
257 if (v >= solv->featurerules && v < solv->featurerules_end)
263 if (!essentialok && (solv->job.elements[-v -1] & SOLVER_ESSENTIAL) != 0)
264 continue; /* not that one! */
267 queue_push(&disabled, v);
269 if (disabled.count != disabledcnt)
272 if (disabled.count == disabledcnt)
274 /* no solution found, this was an invalid suggestion! */
275 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "no solution found!\n");
279 if (!njob && nupdate && nfeature)
281 /* got only update rules, filter out feature rules */
282 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "throwing away feature rules\n");
283 for (i = j = disabledcnt; i < disabled.count; i++)
285 v = disabled.elements[i];
286 if (v < solv->featurerules || v >= solv->featurerules_end)
287 disabled.elements[j++] = v;
292 if (disabled.count == disabledcnt + 1)
294 /* just one suggestion, add it to refined list */
295 v = disabled.elements[disabledcnt];
297 queue_push(refined, v); /* do not record feature rules */
298 solver_disableproblem(solv, v);
299 if (v >= solv->updaterules && v < solv->updaterules_end)
301 Rule *r = solv->rules + (v - solv->updaterules + solv->featurerules);
303 solver_enablerule(solv, r); /* enable corresponding feature rule */
306 solver_reenablepolicyrules(solv, -v);
310 /* more than one solution, disable all */
311 /* do not push anything on refine list, as we do not know which solution to choose */
312 /* thus, the user will get another problem if he selects this solution, where he
313 * can choose the right one */
314 IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
316 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "more than one solution found:\n");
317 for (i = disabledcnt; i < disabled.count; i++)
318 solver_printproblem(solv, disabled.elements[i]);
320 for (i = disabledcnt; i < disabled.count; i++)
322 v = disabled.elements[i];
323 solver_disableproblem(solv, v);
324 if (v >= solv->updaterules && v < solv->updaterules_end)
326 Rule *r = solv->rules + (v - solv->updaterules + solv->featurerules);
328 solver_enablerule(solv, r);
333 /* all done, get us back into the same state as before */
334 /* enable refined rules again */
335 for (i = 0; i < disabled.count; i++)
336 solver_enableproblem(solv, disabled.elements[i]);
337 queue_free(&disabled);
338 /* reset policy rules */
339 for (i = 0; problem[i]; i++)
340 solver_enableproblem(solv, problem[i]);
341 solver_disablepolicyrules(solv);
342 /* disable problem rules again */
343 for (i = 0; problem[i]; i++)
344 solver_disableproblem(solv, problem[i]);
345 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "refine_suggestion end\n");
349 /*-------------------------------------------------------------------
350 * sorting helper for problems
352 * bring update rules before job rules
353 * make essential job rules last
357 problems_sortcmp(const void *ap, const void *bp, void *dp)
360 Id a = *(Id *)ap, b = *(Id *)bp;
367 int af = job->elements[-a - 1] & SOLVER_ESSENTIAL;
368 int bf = job->elements[-b - 1] & SOLVER_ESSENTIAL;
377 * convert a solution rule into a job modifier
380 convertsolution(Solver *solv, Id why, Queue *solutionq)
382 Pool *pool = solv->pool;
385 queue_push(solutionq, 0);
386 queue_push(solutionq, -why);
389 if (why >= solv->infarchrules && why < solv->infarchrules_end)
392 /* infarch rule, find replacement */
393 assert(solv->rules[why].p < 0);
394 name = pool->solvables[-solv->rules[why].p].name;
395 while (why > solv->infarchrules && pool->solvables[-solv->rules[why - 1].p].name == name)
398 for (; why < solv->infarchrules_end && pool->solvables[-solv->rules[why].p].name == name; why++)
399 if (solv->decisionmap[-solv->rules[why].p] > 0)
401 p = -solv->rules[why].p;
405 return; /* false alarm */
406 queue_push(solutionq, SOLVER_SOLUTION_INFARCH);
407 queue_push(solutionq, p);
410 if (why >= solv->duprules && why < solv->duprules_end)
413 /* dist upgrade rule, find replacement */
414 assert(solv->rules[why].p < 0);
415 name = pool->solvables[-solv->rules[why].p].name;
416 while (why > solv->duprules && pool->solvables[-solv->rules[why - 1].p].name == name)
419 for (; why < solv->duprules_end && pool->solvables[-solv->rules[why].p].name == name; why++)
420 if (solv->decisionmap[-solv->rules[why].p] > 0)
422 p = -solv->rules[why].p;
426 return; /* false alarm */
427 queue_push(solutionq, SOLVER_SOLUTION_DISTUPGRADE);
428 queue_push(solutionq, p);
431 if (why >= solv->updaterules && why < solv->updaterules_end)
433 /* update rule, find replacement package */
437 assert(why >= solv->updaterules && why < solv->updaterules_end);
438 /* check if this is a false positive, i.e. the update rule is fulfilled */
439 rr = solv->rules + why;
440 FOR_RULELITERALS(p, dp, rr)
441 if (p > 0 && solv->decisionmap[p] > 0)
444 return; /* false alarm */
446 p = solv->installed->start + (why - solv->updaterules);
447 rr = solv->rules + solv->featurerules + (why - solv->updaterules);
449 rr = solv->rules + why;
450 if (solv->dupmap_all && solv->rules[why].p != p && solv->decisionmap[p] > 0)
452 /* distupgrade case, allow to keep old package */
453 queue_push(solutionq, SOLVER_SOLUTION_DISTUPGRADE);
454 queue_push(solutionq, p);
457 if (solv->decisionmap[p] > 0)
458 return; /* false alarm, turned out we can keep the package */
461 int mvrp = 0; /* multi-version replacement */
462 FOR_RULELITERALS(rp, dp, rr)
464 if (rp > 0 && solv->decisionmap[rp] > 0 && pool->solvables[rp].repo != solv->installed)
467 if (!(solv->noobsoletes.size && MAPTST(&solv->noobsoletes, rp)))
473 /* found only multi-version replacements */
474 /* have to split solution into two parts */
475 queue_push(solutionq, p);
476 queue_push(solutionq, mvrp);
479 queue_push(solutionq, p);
480 queue_push(solutionq, rp);
486 * convert problem data into a form usable for refining.
487 * Returns the number of problems.
490 solver_prepare_solutions(Solver *solv)
494 if (!solv->problems.count)
496 queue_empty(&solv->solutions);
497 queue_push(&solv->solutions, 0); /* dummy so idx is always nonzero */
498 idx = solv->solutions.count;
499 queue_push(&solv->solutions, -1); /* unrefined */
500 /* proofidx stays in position, thus we start with 1 */
501 for (i = 1; i < solv->problems.count; i++)
503 Id p = solv->problems.elements[i];
504 queue_push(&solv->solutions, p);
507 /* end of problem reached */
508 solv->problems.elements[j++] = idx;
509 if (i + 1 >= solv->problems.count)
511 /* start another problem */
512 solv->problems.elements[j++] = solv->problems.elements[++i]; /* copy proofidx */
513 idx = solv->solutions.count;
514 queue_push(&solv->solutions, -1); /* unrefined */
516 solv->problems.count = j;
521 * refine the simple solution rule list provided by
522 * the solver into multiple lists of job modifiers.
525 create_solutions(Solver *solv, int probnr, int solidx)
527 Pool *pool = solv->pool;
529 Queue problem, solution, problems_save;
534 now = solv_timems(0);
536 /* save decisionq, decisionq_why, decisionmap */
537 for (i = 0; i < solv->decisionq.count; i++)
539 Id p = solv->decisionq.elements[i];
540 queue_push(&redoq, p);
541 queue_push(&redoq, solv->decisionq_why.elements[i]);
542 queue_push(&redoq, solv->decisionmap[p > 0 ? p : -p]);
544 /* save problems queue */
545 problems_save = solv->problems;
546 memset(&solv->problems, 0, sizeof(solv->problems));
548 /* extract problem from queue */
549 queue_init(&problem);
550 for (i = solidx + 1; i < solv->solutions.count; i++)
552 Id v = solv->solutions.elements[i];
555 queue_push(&problem, v);
557 if (problem.count > 1)
558 solv_sort(problem.elements, problem.count, sizeof(Id), problems_sortcmp, &solv->job);
559 queue_push(&problem, 0); /* mark end for refine_suggestion */
562 for (i = 0; i < problem.count; i++)
563 printf("PP %d %d\n", i, problem.elements[i]);
566 /* refine each solution element */
569 queue_init(&solution);
570 for (i = 0; i < problem.count; i++)
572 int solstart = solv->solutions.count;
573 refine_suggestion(solv, problem.elements, problem.elements[i], &solution, essentialok);
574 queue_push(&solv->solutions, 0); /* reserve room for number of elements */
575 for (j = 0; j < solution.count; j++)
576 convertsolution(solv, solution.elements[j], &solv->solutions);
577 if (solv->solutions.count == solstart + 1)
579 solv->solutions.count--; /* this one did not work out */
580 if (nsol || i + 1 < problem.count)
581 continue; /* got one or still hope */
584 /* nothing found, start over */
585 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "nothing found, re-run with essentialok = 1\n");
590 /* this is bad, we found no solution */
591 /* for now just offer a rule */
592 POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "nothing found, already did essentialok, fake it\n");
593 queue_push(&solv->solutions, 0);
594 for (j = 0; j < problem.count; j++)
596 convertsolution(solv, problem.elements[j], &solv->solutions);
597 if (solv->solutions.count > solstart + 1)
600 if (solv->solutions.count == solstart + 1)
602 solv->solutions.count--;
603 continue; /* sorry */
606 /* patch in number of solution elements */
607 solv->solutions.elements[solstart] = (solv->solutions.count - (solstart + 1)) / 2;
608 queue_push(&solv->solutions, 0); /* add end marker */
609 queue_push(&solv->solutions, 0); /* add end marker */
610 solv->solutions.elements[solidx + 1 + nsol++] = solstart;
612 solv->solutions.elements[solidx + 1 + nsol] = 0; /* end marker */
613 solv->solutions.elements[solidx] = nsol;
614 queue_free(&problem);
615 queue_free(&solution);
617 /* restore decisions */
618 memset(solv->decisionmap, 0, pool->nsolvables * sizeof(Id));
619 queue_empty(&solv->decisionq);
620 queue_empty(&solv->decisionq_why);
621 for (i = 0; i < redoq.count; i += 3)
623 Id p = redoq.elements[i];
624 queue_push(&solv->decisionq, p);
625 queue_push(&solv->decisionq_why, redoq.elements[i + 1]);
626 solv->decisionmap[p > 0 ? p : -p] = redoq.elements[i + 2];
629 /* restore problems */
630 queue_free(&solv->problems);
631 solv->problems = problems_save;
632 POOL_DEBUG(SOLV_DEBUG_STATS, "create_solutions for problem #%d took %d ms\n", probnr, solv_timems(now));
636 /**************************************************************************/
639 solver_problem_count(Solver *solv)
641 return solv->problems.count / 2;
645 solver_next_problem(Solver *solv, Id problem)
648 return solv->problems.count ? 1 : 0;
649 return (problem + 1) * 2 - 1 < solv->problems.count ? problem + 1 : 0;
653 solver_solution_count(Solver *solv, Id problem)
655 Id solidx = solv->problems.elements[problem * 2 - 1];
656 if (solv->solutions.elements[solidx] < 0)
657 create_solutions(solv, problem, solidx);
658 return solv->solutions.elements[solidx];
662 solver_next_solution(Solver *solv, Id problem, Id solution)
664 Id solidx = solv->problems.elements[problem * 2 - 1];
665 if (solv->solutions.elements[solidx] < 0)
666 create_solutions(solv, problem, solidx);
667 return solv->solutions.elements[solidx + solution + 1] ? solution + 1 : 0;
671 solver_solutionelement_count(Solver *solv, Id problem, Id solution)
673 Id solidx = solv->problems.elements[problem * 2 - 1];
674 solidx = solv->solutions.elements[solidx + solution];
675 return solv->solutions.elements[solidx];
680 * return the next item of the proposed solution
681 * here are the possibilities for p / rp and what
682 * the solver expects the application to do:
684 * -------------------------------------------------------
685 * SOLVER_SOLUTION_INFARCH pkgid
686 * -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
687 * SOLVER_SOLUTION_DISTUPGRADE pkgid
688 * -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
689 * SOLVER_SOLUTION_JOB jobidx
690 * -> remove job (jobidx - 1, jobidx) from job queue
692 * -> add (SOLVER_ERASE|SOLVER_SOLVABLE, p) to the job
693 * pkgid (> 0) pkgid (> 0)
694 * -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
695 * (this will replace package p)
697 * Thus, the solver will either ask the application to remove
698 * a specific job from the job queue, or ask to add an install/erase
704 solver_next_solutionelement(Solver *solv, Id problem, Id solution, Id element, Id *p, Id *rp)
706 Id solidx = solv->problems.elements[problem * 2 - 1];
707 solidx = solv->solutions.elements[solidx + solution];
710 solidx += 1 + element * 2;
711 if (!solv->solutions.elements[solidx] && !solv->solutions.elements[solidx + 1])
713 *p = solv->solutions.elements[solidx];
714 *rp = solv->solutions.elements[solidx + 1];
719 solver_take_solutionelement(Solver *solv, Id p, Id rp, Queue *job)
723 if (p == SOLVER_SOLUTION_JOB)
725 job->elements[rp - 1] = SOLVER_NOOP;
726 job->elements[rp] = 0;
729 if (rp <= 0 && p <= 0)
730 return; /* just in case */
732 p = SOLVER_INSTALL|SOLVER_SOLVABLE;
736 p = SOLVER_ERASE|SOLVER_SOLVABLE;
738 for (i = 0; i < job->count; i += 2)
739 if (job->elements[i] == p && job->elements[i + 1] == rp)
741 queue_push2(job, p, rp);
745 solver_take_solution(Solver *solv, Id problem, Id solution, Queue *job)
747 Id p, rp, element = 0;
748 while ((element = solver_next_solutionelement(solv, problem, solution, element, &p, &rp)) != 0)
749 solver_take_solutionelement(solv, p, rp, job);
753 /*-------------------------------------------------------------------
759 findproblemrule_internal(Solver *solv, Id idx, Id *reqrp, Id *conrp, Id *sysrp, Id *jobrp)
762 Id lreqr, lconr, lsysr, ljobr;
765 int i, reqset = 0; /* 0: unset, 1: installed, 2: jobassert, 3: assert */
767 /* find us a jobassert rule */
768 for (i = idx; (rid = solv->learnt_pool.elements[i]) != 0; i++)
770 if (rid < solv->jobrules || rid >= solv->jobrules_end)
772 r = solv->rules + rid;
773 d = r->d < 0 ? -r->d - 1 : r->d;
774 if (!d && r->w2 == 0 && r->p > 0)
781 /* the problem rules are somewhat ordered from "near to the problem" to
782 * "near to the job" */
783 lreqr = lconr = lsysr = ljobr = 0;
784 while ((rid = solv->learnt_pool.elements[idx++]) != 0)
787 if (rid >= solv->learntrules)
788 findproblemrule_internal(solv, solv->learnt_why.elements[rid - solv->learntrules], &lreqr, &lconr, &lsysr, &ljobr);
789 else if ((rid >= solv->jobrules && rid < solv->jobrules_end) || (rid >= solv->infarchrules && rid < solv->infarchrules_end) || (rid >= solv->duprules && rid < solv->duprules_end))
794 else if (rid >= solv->updaterules && rid < solv->updaterules_end)
801 assert(rid < solv->rpmrules_end);
802 r = solv->rules + rid;
803 d = r->d < 0 ? -r->d - 1 : r->d;
811 if (!d && r->w2 == 0 && reqset < 3)
813 if (*reqrp > 0 && r->p < -1)
815 Id op = -solv->rules[*reqrp].p;
816 if (op > 1 && solv->pool->solvables[op].arch != solv->pool->solvables[-r->p].arch)
817 continue; /* different arch, skip */
819 /* prefer assertions */
823 else if (jobassert && r->p == -jobassert)
825 /* prefer rules of job assertions */
829 else if (solv->installed && r->p < 0 && solv->pool->solvables[-r->p].repo == solv->installed && reqset <= 1)
831 /* prefer rules of job installed package so that the user doesn't get confused by strange packages */
840 if (!*reqrp && lreqr)
842 if (!*conrp && lconr)
844 if (!*jobrp && ljobr)
846 if (!*sysrp && lsysr)
853 * search for a rule that describes the problem to the
854 * user. Actually a pretty hopeless task that may leave the user
855 * puzzled. To get all of the needed information use
856 * solver_findallproblemrules() instead.
860 solver_findproblemrule(Solver *solv, Id problem)
862 Id reqr, conr, sysr, jobr;
863 Id idx = solv->problems.elements[2 * problem - 2];
864 reqr = conr = sysr = jobr = 0;
865 findproblemrule_internal(solv, idx, &reqr, &conr, &sysr, &jobr);
867 return reqr; /* some requires */
869 return conr; /* some conflict */
871 return sysr; /* an update rule */
873 return jobr; /* a user request */
877 /*-------------------------------------------------------------------*/
880 findallproblemrules_internal(Solver *solv, Id idx, Queue *rules)
883 while ((rid = solv->learnt_pool.elements[idx++]) != 0)
885 if (rid >= solv->learntrules)
887 findallproblemrules_internal(solv, solv->learnt_why.elements[rid - solv->learntrules], rules);
890 queue_pushunique(rules, rid);
895 * find all problem rule
897 * return all rules that lead to the problem. This gives the user
898 * all of the information to understand the problem, but the result
899 * can be a large number of rules.
903 solver_findallproblemrules(Solver *solv, Id problem, Queue *rules)
906 findallproblemrules_internal(solv, solv->problems.elements[2 * problem - 2], rules);