xref: /haiku/src/libs/libsolv/solv/problems.c (revision f491972ca97c30b7b4ff6cf072de7bb345d58a69)
1 /*
2  * Copyright (c) 2007-2009, Novell Inc.
3  *
4  * This program is licensed under the BSD license, read LICENSE.BSD
5  * for further information
6  */
7 
8 /*
9  * problems.c
10  *
11  */
12 
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <unistd.h>
16 #include <string.h>
17 #include <assert.h>
18 
19 #include "solver.h"
20 #include "solver_private.h"
21 #include "bitmap.h"
22 #include "pool.h"
23 #include "util.h"
24 #include "evr.h"
25 #include "solverdebug.h"
26 
27 
28 /**********************************************************************************/
29 
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.
33  */
34 
35 void
solver_disableproblem(Solver * solv,Id v)36 solver_disableproblem(Solver *solv, Id v)
37 {
38   Rule *r;
39   int i;
40   Id *jp;
41 
42   if (v > 0)
43     {
44       if (v >= solv->infarchrules && v < solv->infarchrules_end)
45 	{
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)
49 	    v--;
50 	  for (; v < solv->infarchrules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
51 	    solver_disablerule(solv, solv->rules + v);
52 	  return;
53 	}
54       if (v >= solv->duprules && v < solv->duprules_end)
55 	{
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)
59 	    v--;
60 	  for (; v < solv->duprules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
61 	    solver_disablerule(solv, solv->rules + v);
62 	  return;
63 	}
64       solver_disablerule(solv, solv->rules + v);
65 #if 0
66       /* XXX: doesn't work */
67       if (v >= solv->updaterules && v < solv->updaterules_end)
68 	{
69 	  /* enable feature rule if we disabled the update rule */
70 	  r = solv->rules + (v - solv->updaterules + solv->featurerules);
71 	  if (r->p)
72 	    solver_enablerule(solv, r);
73 	}
74 #endif
75       return;
76     }
77   v = -(v + 1);
78   jp = solv->ruletojob.elements;
79   for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++, jp++)
80     if (*jp == v)
81       solver_disablerule(solv, r);
82 }
83 
84 /*-------------------------------------------------------------------
85  * enableproblem
86  */
87 
88 void
solver_enableproblem(Solver * solv,Id v)89 solver_enableproblem(Solver *solv, Id v)
90 {
91   Rule *r;
92   int i;
93   Id *jp;
94 
95   if (v > 0)
96     {
97       if (v >= solv->infarchrules && v < solv->infarchrules_end)
98 	{
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)
102 	    v--;
103 	  for (; v < solv->infarchrules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
104 	    solver_enablerule(solv, solv->rules + v);
105 	  return;
106 	}
107       if (v >= solv->duprules && v < solv->duprules_end)
108 	{
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)
112 	    v--;
113 	  for (; v < solv->duprules_end && pool->solvables[-solv->rules[v].p].name == name; v++)
114 	    solver_enablerule(solv, solv->rules + v);
115 	  return;
116 	}
117       if (v >= solv->featurerules && v < solv->featurerules_end)
118 	{
119 	  /* do not enable feature rule if update rule is enabled */
120 	  r = solv->rules + (v - solv->featurerules + solv->updaterules);
121 	  if (r->d >= 0)
122 	    return;
123 	}
124       solver_enablerule(solv, solv->rules + v);
125       if (v >= solv->updaterules && v < solv->updaterules_end)
126 	{
127 	  /* disable feature rule when enabling update rule */
128 	  r = solv->rules + (v - solv->updaterules + solv->featurerules);
129 	  if (r->p)
130 	    solver_disablerule(solv, r);
131 	}
132       return;
133     }
134   v = -(v + 1);
135   jp = solv->ruletojob.elements;
136   for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++, jp++)
137     if (*jp == v)
138       solver_enablerule(solv, r);
139 }
140 
141 
142 /*-------------------------------------------------------------------
143  * enable weak rules
144  *
145  * Reenable all disabled weak rules (marked in weakrulemap)
146  *
147  */
148 
149 static void
enableweakrules(Solver * solv)150 enableweakrules(Solver *solv)
151 {
152   int i;
153   Rule *r;
154 
155   for (i = 1, r = solv->rules + i; i < solv->learntrules; i++, r++)
156     {
157       if (r->d >= 0) /* already enabled? */
158 	continue;
159       if (!MAPTST(&solv->weakrulemap, i))
160 	continue;
161       solver_enablerule(solv, r);
162     }
163 }
164 
165 
166 /*-------------------------------------------------------------------
167  *
168  * refine_suggestion
169  *
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.
173  */
174 
175 /* FIXME: think about conflicting assertions */
176 
177 static void
refine_suggestion(Solver * solv,Id * problem,Id sug,Queue * refined,int essentialok)178 refine_suggestion(Solver *solv, Id *problem, Id sug, Queue *refined, int essentialok)
179 {
180   Pool *pool = solv->pool;
181   int i, j;
182   Id v;
183   Queue disabled;
184   int disabledcnt;
185 
186   IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
187     {
188       POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "refine_suggestion start\n");
189       for (i = 0; problem[i]; i++)
190 	{
191 	  if (problem[i] == sug)
192 	    POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "=> ");
193 	  solver_printproblem(solv, problem[i]);
194 	}
195     }
196   queue_empty(refined);
197   if (!essentialok && sug < 0 && (solv->job.elements[-sug - 1] & SOLVER_ESSENTIAL) != 0)
198     return;
199   queue_init(&disabled);
200   queue_push(refined, sug);
201 
202   /* re-enable all problem rules with the exception of "sug"(gestion) */
203   solver_reset(solv);
204 
205   for (i = 0; problem[i]; i++)
206     if (problem[i] != sug)
207       solver_enableproblem(solv, problem[i]);
208 
209   if (sug < 0)
210     solver_reenablepolicyrules(solv, -sug);
211   else if (sug >= solv->updaterules && sug < solv->updaterules_end)
212     {
213       /* enable feature rule */
214       Rule *r = solv->rules + solv->featurerules + (sug - solv->updaterules);
215       if (r->p)
216 	solver_enablerule(solv, r);
217     }
218 
219   enableweakrules(solv);
220 
221   for (;;)
222     {
223       int njob, nfeature, nupdate, pass;
224       queue_empty(&solv->problems);
225       solver_reset(solv);
226 
227       if (!solv->problems.count)
228         solver_run_sat(solv, 0, 0);
229 
230       if (!solv->problems.count)
231 	{
232 	  POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "no more problems!\n");
233 	  break;		/* great, no more problems */
234 	}
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++)
239 	{
240 	  for (i = 1; i < solv->problems.count - 1; i++)
241 	    {
242 	      /* ignore solutions in refined */
243 	      v = solv->problems.elements[i];
244 	      if (v == 0)
245 		break;	/* end of problem reached */
246 	      if (sug != v)
247 		{
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))
253 		      break;
254 		  if (problem[j] == v)
255 		    continue;
256 		}
257 	      if (v >= solv->featurerules && v < solv->featurerules_end)
258 		nfeature++;
259 	      else if (v > 0)
260 		nupdate++;
261 	      else
262 		{
263 		  if (!essentialok && (solv->job.elements[-v - 1] & SOLVER_ESSENTIAL) != 0)
264 		    continue;	/* not that one! */
265 		  njob++;
266 		}
267 	      queue_push(&disabled, v);
268 	    }
269 	  if (disabled.count != disabledcnt)
270 	    break;
271 	}
272       if (disabled.count == disabledcnt)
273 	{
274 	  /* no solution found, this was an invalid suggestion! */
275 	  POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "no solution found!\n");
276 	  refined->count = 0;
277 	  break;
278 	}
279       if (!njob && nupdate && nfeature)
280 	{
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++)
284 	    {
285 	      v = disabled.elements[i];
286 	      if (v < solv->featurerules || v >= solv->featurerules_end)
287 	        disabled.elements[j++] = v;
288 	    }
289 	  disabled.count = j;
290 	  nfeature = 0;
291 	}
292       if (disabled.count == disabledcnt + 1)
293 	{
294 	  /* just one suggestion, add it to refined list */
295 	  v = disabled.elements[disabledcnt];
296 	  if (!nfeature && v != sug)
297 	    queue_push(refined, v);	/* do not record feature rules */
298 	  solver_disableproblem(solv, v);
299 	  if (v >= solv->updaterules && v < solv->updaterules_end)
300 	    {
301 	      Rule *r = solv->rules + (v - solv->updaterules + solv->featurerules);
302 	      if (r->p)
303 		solver_enablerule(solv, r);	/* enable corresponding feature rule */
304 	    }
305 	  if (v < 0)
306 	    solver_reenablepolicyrules(solv, -v);
307 	}
308       else
309 	{
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)
315 	    {
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]);
319 	    }
320 	  for (i = disabledcnt; i < disabled.count; i++)
321 	    {
322 	      v = disabled.elements[i];
323 	      solver_disableproblem(solv, v);
324 	      if (v >= solv->updaterules && v < solv->updaterules_end)
325 		{
326 		  Rule *r = solv->rules + (v - solv->updaterules + solv->featurerules);
327 		  if (r->p)
328 		    solver_enablerule(solv, r);
329 		}
330 	    }
331 	}
332     }
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");
346 }
347 
348 
349 /*-------------------------------------------------------------------
350  * sorting helper for problems
351  *
352  * bring update rules before job rules
353  * make essential job rules last
354  */
355 
356 static int
problems_sortcmp(const void * ap,const void * bp,void * dp)357 problems_sortcmp(const void *ap, const void *bp, void *dp)
358 {
359   Queue *job = dp;
360   Id a = *(Id *)ap, b = *(Id *)bp;
361   if (a < 0 && b > 0)
362     return 1;
363   if (a > 0 && b < 0)
364     return -1;
365   if (a < 0 && b < 0)
366     {
367       int af = job->elements[-a - 1] & SOLVER_ESSENTIAL;
368       int bf = job->elements[-b - 1] & SOLVER_ESSENTIAL;
369       int x = af - bf;
370       if (x)
371 	return x;
372     }
373   return a - b;
374 }
375 
376 /*
377  * convert a solution rule into a job modifier
378  */
379 static void
convertsolution(Solver * solv,Id why,Queue * solutionq)380 convertsolution(Solver *solv, Id why, Queue *solutionq)
381 {
382   Pool *pool = solv->pool;
383   if (why < 0)
384     {
385       why = -why;
386       if (why < solv->pooljobcnt)
387 	{
388 	  queue_push(solutionq, SOLVER_SOLUTION_POOLJOB);
389 	  queue_push(solutionq, why);
390 	}
391       else
392 	{
393 	  queue_push(solutionq, SOLVER_SOLUTION_JOB);
394 	  queue_push(solutionq, why - solv->pooljobcnt);
395 	}
396       return;
397     }
398   if (why >= solv->infarchrules && why < solv->infarchrules_end)
399     {
400       Id p, name;
401       /* infarch rule, find replacement */
402       assert(solv->rules[why].p < 0);
403       name = pool->solvables[-solv->rules[why].p].name;
404       while (why > solv->infarchrules && pool->solvables[-solv->rules[why - 1].p].name == name)
405 	why--;
406       p = 0;
407       for (; why < solv->infarchrules_end && pool->solvables[-solv->rules[why].p].name == name; why++)
408 	if (solv->decisionmap[-solv->rules[why].p] > 0)
409 	  {
410 	    p = -solv->rules[why].p;
411 	    break;
412 	  }
413       if (!p)
414 	return;		/* false alarm */
415       queue_push(solutionq, SOLVER_SOLUTION_INFARCH);
416       queue_push(solutionq, p);
417       return;
418     }
419   if (why >= solv->duprules && why < solv->duprules_end)
420     {
421       Id p, name;
422       /* dist upgrade rule, find replacement */
423       assert(solv->rules[why].p < 0);
424       name = pool->solvables[-solv->rules[why].p].name;
425       while (why > solv->duprules && pool->solvables[-solv->rules[why - 1].p].name == name)
426 	why--;
427       p = 0;
428       for (; why < solv->duprules_end && pool->solvables[-solv->rules[why].p].name == name; why++)
429 	if (solv->decisionmap[-solv->rules[why].p] > 0)
430 	  {
431 	    p = -solv->rules[why].p;
432 	    break;
433 	  }
434       if (!p)
435 	return;		/* false alarm */
436       queue_push(solutionq, SOLVER_SOLUTION_DISTUPGRADE);
437       queue_push(solutionq, p);
438       return;
439     }
440   if (why >= solv->updaterules && why < solv->updaterules_end)
441     {
442       /* update rule, find replacement package */
443       Id p, pp, rp = 0;
444       Rule *rr;
445 
446       /* check if this is a false positive, i.e. the update rule is fulfilled */
447       rr = solv->rules + why;
448       FOR_RULELITERALS(p, pp, rr)
449 	if (p > 0 && solv->decisionmap[p] > 0)
450 	  return;	/* false alarm */
451 
452       p = solv->installed->start + (why - solv->updaterules);
453       if (solv->dupmap_all && solv->rules[why].p != p && solv->decisionmap[p] > 0)
454 	{
455 	  /* distupgrade case, allow to keep old package */
456 	  queue_push(solutionq, SOLVER_SOLUTION_DISTUPGRADE);
457 	  queue_push(solutionq, p);
458 	  return;
459 	}
460       if (solv->decisionmap[p] > 0)
461 	return;		/* false alarm, turned out we can keep the package */
462       rr = solv->rules + solv->featurerules + (why - solv->updaterules);
463       if (!rr->p)
464 	rr = solv->rules + why;
465       if (rr->w2)
466 	{
467 	  int mvrp = 0;		/* multi-version replacement */
468 	  FOR_RULELITERALS(rp, pp, rr)
469 	    {
470 	      if (rp > 0 && solv->decisionmap[rp] > 0 && pool->solvables[rp].repo != solv->installed)
471 		{
472 		  mvrp = rp;
473 		  if (!(solv->multiversion.size && MAPTST(&solv->multiversion, rp)))
474 		    break;
475 		}
476 	    }
477 	  if (!rp && mvrp)
478 	    {
479 	      /* found only multi-version replacements */
480 	      /* have to split solution into two parts */
481 	      queue_push(solutionq, p);
482 	      queue_push(solutionq, mvrp);
483 	    }
484 	}
485       queue_push(solutionq, p);
486       queue_push(solutionq, rp);
487       return;
488     }
489   if (why >= solv->bestrules && why < solv->bestrules_end)
490     {
491       int mvrp;
492       Id p, pp, rp = 0;
493       Rule *rr;
494       /* check false positive */
495       rr = solv->rules + why;
496       FOR_RULELITERALS(p, pp, rr)
497 	if (p > 0 && solv->decisionmap[p] > 0)
498 	  return;	/* false alarm */
499       /* check update/feature rule */
500       p = solv->bestrules_pkg[why - solv->bestrules];
501       if (p < 0)
502 	{
503 	  /* install job */
504 	  queue_push(solutionq, 0);
505 	  queue_push(solutionq, solv->ruletojob.elements[-p - solv->jobrules] + 1);
506 	  return;
507 	}
508       if (solv->decisionmap[p] > 0)
509 	{
510 	  /* disable best rule by keeping the old package */
511 	  queue_push(solutionq, SOLVER_SOLUTION_BEST);
512 	  queue_push(solutionq, p);
513 	  return;
514 	}
515       rr = solv->rules + solv->featurerules + (p - solv->installed->start);
516       if (!rr->p)
517 	rr = solv->rules + solv->updaterules + (p - solv->installed->start);
518       mvrp = 0;		/* multi-version replacement */
519       FOR_RULELITERALS(rp, pp, rr)
520 	if (rp > 0 && solv->decisionmap[rp] > 0 && pool->solvables[rp].repo != solv->installed)
521 	  {
522 	    mvrp = rp;
523 	    if (!(solv->multiversion.size && MAPTST(&solv->multiversion, rp)))
524 	      break;
525 	  }
526       if (!rp && mvrp)
527 	{
528 	  queue_push(solutionq, SOLVER_SOLUTION_BEST);	/* split, see above */
529 	  queue_push(solutionq, mvrp);
530 	  queue_push(solutionq, p);
531 	  queue_push(solutionq, 0);
532 	  return;
533 	}
534       if (rp)
535 	{
536 	  queue_push(solutionq, SOLVER_SOLUTION_BEST);
537 	  queue_push(solutionq, rp);
538 	}
539       return;
540     }
541 }
542 
543 /*
544  * convert problem data into a form usable for refining.
545  * Returns the number of problems.
546  */
547 int
solver_prepare_solutions(Solver * solv)548 solver_prepare_solutions(Solver *solv)
549 {
550   int i, j = 1, idx;
551 
552   if (!solv->problems.count)
553     return 0;
554   queue_empty(&solv->solutions);
555   queue_push(&solv->solutions, 0);	/* dummy so idx is always nonzero */
556   idx = solv->solutions.count;
557   queue_push(&solv->solutions, -1);	/* unrefined */
558   /* proofidx stays in position, thus we start with 1 */
559   for (i = 1; i < solv->problems.count; i++)
560     {
561       Id p = solv->problems.elements[i];
562       queue_push(&solv->solutions, p);
563       if (p)
564         continue;
565       /* end of problem reached */
566       solv->problems.elements[j++] = idx;
567       if (i + 1 >= solv->problems.count)
568         break;
569       /* start another problem */
570       solv->problems.elements[j++] = solv->problems.elements[++i];  /* copy proofidx */
571       idx = solv->solutions.count;
572       queue_push(&solv->solutions, -1);	/* unrefined */
573     }
574   solv->problems.count = j;
575   return j / 2;
576 }
577 
578 /*
579  * refine the simple solution rule list provided by
580  * the solver into multiple lists of job modifiers.
581  */
582 static void
create_solutions(Solver * solv,int probnr,int solidx)583 create_solutions(Solver *solv, int probnr, int solidx)
584 {
585   Pool *pool = solv->pool;
586   Queue redoq;
587   Queue problem, solution, problems_save;
588   int i, j, nsol;
589   int essentialok;
590   unsigned int now;
591   int oldmistakes = solv->cleandeps_mistakes ? solv->cleandeps_mistakes->count : 0;
592   Id extraflags = -1;
593 
594   now = solv_timems(0);
595   queue_init(&redoq);
596   /* save decisionq, decisionq_why, decisionmap */
597   for (i = 0; i < solv->decisionq.count; i++)
598     {
599       Id p = solv->decisionq.elements[i];
600       queue_push(&redoq, p);
601       queue_push(&redoq, solv->decisionq_why.elements[i]);
602       queue_push(&redoq, solv->decisionmap[p > 0 ? p : -p]);
603     }
604   /* save problems queue */
605   problems_save = solv->problems;
606   memset(&solv->problems, 0, sizeof(solv->problems));
607 
608   /* extract problem from queue */
609   queue_init(&problem);
610   for (i = solidx + 1; i < solv->solutions.count; i++)
611     {
612       Id v = solv->solutions.elements[i];
613       if (!v)
614 	break;
615       queue_push(&problem, v);
616       if (v < 0)
617 	extraflags &= solv->job.elements[-v - 1];
618     }
619   if (extraflags == -1)
620     extraflags = 0;
621   if (problem.count > 1)
622     solv_sort(problem.elements, problem.count, sizeof(Id), problems_sortcmp, &solv->job);
623   queue_push(&problem, 0);	/* mark end for refine_suggestion */
624   problem.count--;
625 #if 0
626   for (i = 0; i < problem.count; i++)
627     printf("PP %d %d\n", i, problem.elements[i]);
628 #endif
629 
630   /* refine each solution element */
631   nsol = 0;
632   essentialok = 0;
633   queue_init(&solution);
634   for (i = 0; i < problem.count; i++)
635     {
636       int solstart = solv->solutions.count;
637       refine_suggestion(solv, problem.elements, problem.elements[i], &solution, essentialok);
638       queue_push(&solv->solutions, 0);	/* reserve room for number of elements */
639       for (j = 0; j < solution.count; j++)
640 	convertsolution(solv, solution.elements[j], &solv->solutions);
641       if (solv->solutions.count == solstart + 1)
642 	{
643 	  solv->solutions.count--;	/* this one did not work out */
644 	  if (nsol || i + 1 < problem.count)
645 	    continue;			/* got one or still hope */
646 	  if (!essentialok)
647 	    {
648 	      /* nothing found, start over */
649 	      POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "nothing found, re-run with essentialok = 1\n");
650 	      essentialok = 1;
651 	      i = -1;
652 	      continue;
653 	    }
654 	  /* this is bad, we found no solution */
655 	  /* for now just offer a rule */
656 	  POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "nothing found, already did essentialok, fake it\n");
657 	  queue_push(&solv->solutions, 0);
658 	  for (j = 0; j < problem.count; j++)
659 	    {
660 	      convertsolution(solv, problem.elements[j], &solv->solutions);
661 	      if (solv->solutions.count > solstart + 1)
662 		break;
663 	    }
664 	  if (solv->solutions.count == solstart + 1)
665 	    {
666 	      solv->solutions.count--;
667 	      continue;		/* sorry */
668 	    }
669 	}
670       /* patch in number of solution elements */
671       solv->solutions.elements[solstart] = (solv->solutions.count - (solstart + 1)) / 2;
672       queue_push(&solv->solutions, 0);	/* add end marker */
673       queue_push(&solv->solutions, 0);	/* add end marker */
674       queue_push(&solv->solutions, problem.elements[i]);	/* just for bookkeeping */
675       queue_push(&solv->solutions, extraflags & SOLVER_CLEANDEPS);	/* our extraflags */
676       solv->solutions.elements[solidx + 1 + nsol++] = solstart;
677     }
678   solv->solutions.elements[solidx + 1 + nsol] = 0;	/* end marker */
679   solv->solutions.elements[solidx] = nsol;
680   queue_free(&problem);
681   queue_free(&solution);
682 
683   /* restore decisions */
684   memset(solv->decisionmap, 0, pool->nsolvables * sizeof(Id));
685   queue_empty(&solv->decisionq);
686   queue_empty(&solv->decisionq_why);
687   for (i = 0; i < redoq.count; i += 3)
688     {
689       Id p = redoq.elements[i];
690       queue_push(&solv->decisionq, p);
691       queue_push(&solv->decisionq_why, redoq.elements[i + 1]);
692       solv->decisionmap[p > 0 ? p : -p] = redoq.elements[i + 2];
693     }
694   queue_free(&redoq);
695   /* restore problems */
696   queue_free(&solv->problems);
697   solv->problems = problems_save;
698 
699   if (solv->cleandeps_mistakes)
700     {
701       if (oldmistakes)
702 	queue_truncate(solv->cleandeps_mistakes, oldmistakes);
703       else
704 	{
705 	  queue_free(solv->cleandeps_mistakes);
706 	  solv->cleandeps_mistakes = solv_free(solv->cleandeps_mistakes);
707 	}
708     }
709 
710   POOL_DEBUG(SOLV_DEBUG_STATS, "create_solutions for problem #%d took %d ms\n", probnr, solv_timems(now));
711 }
712 
713 
714 /**************************************************************************/
715 
716 unsigned int
solver_problem_count(Solver * solv)717 solver_problem_count(Solver *solv)
718 {
719   return solv->problems.count / 2;
720 }
721 
722 Id
solver_next_problem(Solver * solv,Id problem)723 solver_next_problem(Solver *solv, Id problem)
724 {
725   if (!problem)
726     return solv->problems.count ? 1 : 0;
727   return (problem + 1) * 2 - 1 < solv->problems.count ? problem + 1 : 0;
728 }
729 
730 unsigned int
solver_solution_count(Solver * solv,Id problem)731 solver_solution_count(Solver *solv, Id problem)
732 {
733   Id solidx = solv->problems.elements[problem * 2 - 1];
734   if (solv->solutions.elements[solidx] < 0)
735     create_solutions(solv, problem, solidx);
736   return solv->solutions.elements[solidx];
737 }
738 
739 Id
solver_next_solution(Solver * solv,Id problem,Id solution)740 solver_next_solution(Solver *solv, Id problem, Id solution)
741 {
742   Id solidx = solv->problems.elements[problem * 2 - 1];
743   if (solv->solutions.elements[solidx] < 0)
744     create_solutions(solv, problem, solidx);
745   return solv->solutions.elements[solidx + solution + 1] ? solution + 1 : 0;
746 }
747 
748 unsigned int
solver_solutionelement_count(Solver * solv,Id problem,Id solution)749 solver_solutionelement_count(Solver *solv, Id problem, Id solution)
750 {
751   Id solidx = solv->problems.elements[problem * 2 - 1];
752   solidx = solv->solutions.elements[solidx + solution];
753   return solv->solutions.elements[solidx];
754 }
755 
756 Id
solver_solutionelement_internalid(Solver * solv,Id problem,Id solution)757 solver_solutionelement_internalid(Solver *solv, Id problem, Id solution)
758 {
759   Id solidx = solv->problems.elements[problem * 2 - 1];
760   solidx = solv->solutions.elements[solidx + solution];
761   return solv->solutions.elements[solidx + 2 * solv->solutions.elements[solidx] + 3];
762 }
763 
764 Id
solver_solutionelement_extrajobflags(Solver * solv,Id problem,Id solution)765 solver_solutionelement_extrajobflags(Solver *solv, Id problem, Id solution)
766 {
767   Id solidx = solv->problems.elements[problem * 2 - 1];
768   solidx = solv->solutions.elements[solidx + solution];
769   return solv->solutions.elements[solidx + 2 * solv->solutions.elements[solidx] + 4];
770 }
771 
772 
773 /*
774  *  return the next item of the proposed solution
775  *  here are the possibilities for p / rp and what
776  *  the solver expects the application to do:
777  *    p                             rp
778  *  -------------------------------------------------------
779  *    SOLVER_SOLUTION_INFARCH       pkgid
780  *    -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
781  *    SOLVER_SOLUTION_DISTUPGRADE   pkgid
782  *    -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
783  *    SOLVER_SOLUTION_BEST          pkgid
784  *    -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
785  *    SOLVER_SOLUTION_JOB           jobidx
786  *    -> remove job (jobidx - 1, jobidx) from job queue
787  *    SOLVER_SOLUTION_POOLJOB       jobidx
788  *    -> remove job (jobidx - 1, jobidx) from pool job queue
789  *    pkgid (> 0)                   0
790  *    -> add (SOLVER_ERASE|SOLVER_SOLVABLE, p) to the job
791  *    pkgid (> 0)                   pkgid (> 0)
792  *    -> add (SOLVER_INSTALL|SOLVER_SOLVABLE, rp) to the job
793  *       (this will replace package p)
794  *
795  * Thus, the solver will either ask the application to remove
796  * a specific job from the job queue, or ask to add an install/erase
797  * job to it.
798  *
799  */
800 
801 Id
solver_next_solutionelement(Solver * solv,Id problem,Id solution,Id element,Id * p,Id * rp)802 solver_next_solutionelement(Solver *solv, Id problem, Id solution, Id element, Id *p, Id *rp)
803 {
804   Id solidx = solv->problems.elements[problem * 2 - 1];
805   solidx = solv->solutions.elements[solidx + solution];
806   if (!solidx)
807     return 0;
808   solidx += 1 + element * 2;
809   if (!solv->solutions.elements[solidx] && !solv->solutions.elements[solidx + 1])
810     return 0;
811   *p = solv->solutions.elements[solidx];
812   *rp = solv->solutions.elements[solidx + 1];
813   return element + 1;
814 }
815 
816 void
solver_take_solutionelement(Solver * solv,Id p,Id rp,Id extrajobflags,Queue * job)817 solver_take_solutionelement(Solver *solv, Id p, Id rp, Id extrajobflags, Queue *job)
818 {
819   int i;
820 
821   if (p == SOLVER_SOLUTION_POOLJOB)
822     {
823       solv->pool->pooljobs.elements[rp - 1] = SOLVER_NOOP;
824       solv->pool->pooljobs.elements[rp] = 0;
825       return;
826     }
827   if (p == SOLVER_SOLUTION_JOB)
828     {
829       job->elements[rp - 1] = SOLVER_NOOP;
830       job->elements[rp] = 0;
831       return;
832     }
833   if (rp <= 0 && p <= 0)
834     return;	/* just in case */
835   if (rp > 0)
836     p = SOLVER_INSTALL|SOLVER_SOLVABLE|extrajobflags;
837   else
838     {
839       rp = p;
840       p = SOLVER_ERASE|SOLVER_SOLVABLE|extrajobflags;
841     }
842   for (i = 0; i < job->count; i += 2)
843     if (job->elements[i] == p && job->elements[i + 1] == rp)
844       return;
845   queue_push2(job, p, rp);
846 }
847 
848 void
solver_take_solution(Solver * solv,Id problem,Id solution,Queue * job)849 solver_take_solution(Solver *solv, Id problem, Id solution, Queue *job)
850 {
851   Id p, rp, element = 0;
852   Id extrajobflags = solver_solutionelement_extrajobflags(solv, problem, solution);
853   while ((element = solver_next_solutionelement(solv, problem, solution, element, &p, &rp)) != 0)
854     solver_take_solutionelement(solv, p, rp, extrajobflags, job);
855 }
856 
857 
858 /*-------------------------------------------------------------------
859  *
860  * find problem rule
861  */
862 
863 static void
findproblemrule_internal(Solver * solv,Id idx,Id * reqrp,Id * conrp,Id * sysrp,Id * jobrp,Map * rseen)864 findproblemrule_internal(Solver *solv, Id idx, Id *reqrp, Id *conrp, Id *sysrp, Id *jobrp, Map *rseen)
865 {
866   Id rid, d;
867   Id lreqr, lconr, lsysr, ljobr;
868   Rule *r;
869   Id jobassert = 0;
870   int i, reqset = 0;	/* 0: unset, 1: installed, 2: jobassert, 3: assert */
871 
872   /* find us a jobassert rule */
873   for (i = idx; (rid = solv->learnt_pool.elements[i]) != 0; i++)
874     {
875       if (rid < solv->jobrules || rid >= solv->jobrules_end)
876 	continue;
877       r = solv->rules + rid;
878       d = r->d < 0 ? -r->d - 1 : r->d;
879       if (!d && r->w2 == 0 && r->p > 0)
880 	{
881 	  jobassert = r->p;
882 	  break;
883 	}
884     }
885 
886   /* the problem rules are somewhat ordered from "near to the problem" to
887    * "near to the job" */
888   lreqr = lconr = lsysr = ljobr = 0;
889   while ((rid = solv->learnt_pool.elements[idx++]) != 0)
890     {
891       assert(rid > 0);
892       if (rid >= solv->learntrules)
893 	{
894 	  if (MAPTST(rseen, rid - solv->learntrules))
895 	    continue;
896 	  MAPSET(rseen, rid - solv->learntrules);
897 	  findproblemrule_internal(solv, solv->learnt_why.elements[rid - solv->learntrules], &lreqr, &lconr, &lsysr, &ljobr, rseen);
898 	}
899       else if ((rid >= solv->jobrules && rid < solv->jobrules_end) || (rid >= solv->infarchrules && rid < solv->infarchrules_end) || (rid >= solv->duprules && rid < solv->duprules_end) || (rid >= solv->bestrules && rid < solv->bestrules_end))
900 	{
901 	  if (!*jobrp)
902 	    *jobrp = rid;
903 	}
904       else if (rid >= solv->updaterules && rid < solv->updaterules_end)
905 	{
906 	  if (!*sysrp)
907 	    *sysrp = rid;
908 	}
909       else
910 	{
911 	  assert(rid < solv->rpmrules_end);
912 	  r = solv->rules + rid;
913 	  d = r->d < 0 ? -r->d - 1 : r->d;
914 	  if (!d && r->w2 < 0)
915 	    {
916 	      if (!*conrp)
917 		*conrp = rid;
918 	    }
919 	  else
920 	    {
921 	      if (!d && r->w2 == 0 && reqset < 3)
922 		{
923 		  if (*reqrp > 0 && r->p < -1)
924 		    {
925 		      Id op = -solv->rules[*reqrp].p;
926 		      if (op > 1 && solv->pool->solvables[op].arch != solv->pool->solvables[-r->p].arch)
927 			continue;	/* different arch, skip */
928 		    }
929 		  /* prefer assertions */
930 		  *reqrp = rid;
931 		  reqset = 3;
932 		}
933 	      else if (jobassert && r->p == -jobassert)
934 		{
935 		  /* prefer rules of job assertions */
936 		  *reqrp = rid;
937 		  reqset = 2;
938 		}
939 	      else if (solv->installed && r->p < 0 && solv->pool->solvables[-r->p].repo == solv->installed && reqset <= 1)
940 		{
941 		  /* prefer rules of job installed package so that the user doesn't get confused by strange packages */
942 		  *reqrp = rid;
943 		  reqset = 1;
944 		}
945 	      else if (!*reqrp)
946 		*reqrp = rid;
947 	    }
948 	}
949     }
950   if (!*reqrp && lreqr)
951     *reqrp = lreqr;
952   if (!*conrp && lconr)
953     *conrp = lconr;
954   if (!*jobrp && ljobr)
955     *jobrp = ljobr;
956   if (!*sysrp && lsysr)
957     *sysrp = lsysr;
958 }
959 
960 /*
961  * find problem rule
962  *
963  * search for a rule that describes the problem to the
964  * user. Actually a pretty hopeless task that may leave the user
965  * puzzled. To get all of the needed information use
966  * solver_findallproblemrules() instead.
967  */
968 
969 Id
solver_findproblemrule(Solver * solv,Id problem)970 solver_findproblemrule(Solver *solv, Id problem)
971 {
972   Id reqr, conr, sysr, jobr;
973   Id idx = solv->problems.elements[2 * problem - 2];
974   Map rseen;
975   reqr = conr = sysr = jobr = 0;
976   map_init(&rseen, solv->learntrules ? solv->nrules - solv->learntrules : 0);
977   findproblemrule_internal(solv, idx, &reqr, &conr, &sysr, &jobr, &rseen);
978   map_free(&rseen);
979   if (reqr)
980     return reqr;	/* some requires */
981   if (conr)
982     return conr;	/* some conflict */
983   if (sysr)
984     return sysr;	/* an update rule */
985   if (jobr)
986     return jobr;	/* a user request */
987   assert(0);
988   return 0;
989 }
990 
991 /*-------------------------------------------------------------------*/
992 
993 static void
findallproblemrules_internal(Solver * solv,Id idx,Queue * rules,Map * rseen)994 findallproblemrules_internal(Solver *solv, Id idx, Queue *rules, Map *rseen)
995 {
996   Id rid;
997   while ((rid = solv->learnt_pool.elements[idx++]) != 0)
998     {
999       if (rid >= solv->learntrules)
1000         {
1001 	  if (MAPTST(rseen, rid - solv->learntrules))
1002 	    continue;
1003 	  MAPSET(rseen, rid - solv->learntrules);
1004 	  findallproblemrules_internal(solv, solv->learnt_why.elements[rid - solv->learntrules], rules, rseen);
1005           continue;
1006 	}
1007       queue_pushunique(rules, rid);
1008     }
1009 }
1010 
1011 /*
1012  * find all problem rule
1013  *
1014  * return all rules that lead to the problem. This gives the user
1015  * all of the information to understand the problem, but the result
1016  * can be a large number of rules.
1017  */
1018 
1019 void
solver_findallproblemrules(Solver * solv,Id problem,Queue * rules)1020 solver_findallproblemrules(Solver *solv, Id problem, Queue *rules)
1021 {
1022   Map rseen;
1023   queue_empty(rules);
1024   map_init(&rseen, solv->learntrules ? solv->nrules - solv->learntrules : 0);
1025   findallproblemrules_internal(solv, solv->problems.elements[2 * problem - 2], rules, &rseen);
1026   map_free(&rseen);
1027 }
1028 
1029 /* EOF */
1030