src/solver.c

   1 /*
   2  * Copyright (c) 2007-2008, Novell Inc.
   3  *
   4  * This program is licensed under the BSD license, read LICENSE.BSD
   5  * for further information
   6  */
   7
   8 /*
   9  * solver.c
  10  *
  11  * SAT based dependency solver
  12  */
  13
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <unistd.h>
  17 #include <string.h>
  18 #include <assert.h>
  19
  20 #include "solver.h"
  21 #include "bitmap.h"
  22 #include "pool.h"
  23 #include "util.h"
  24 #include "policy.h"
  25 #include "solverdebug.h"
  26
  27 #define RULES_BLOCK 63
  28
  29 /********************************************************************
  30  *
  31  * dependency check helpers
  32  *
  33  */
  34
  35 /*-------------------------------------------------------------------
  36  * handle split provides
  37  */
  38
  39 int
  40 solver_splitprovides(Solver *solv, Id dep)
  41 {
  42   Pool *pool = solv->pool;
  43   Id p, pp;
  44   Reldep *rd;
  45   Solvable *s;
  46
  47   if (!solv->dosplitprovides || !solv->installed)
  48     return 0;
  49   if (!ISRELDEP(dep))
  50     return 0;
  51   rd = GETRELDEP(pool, dep);
  52   if (rd->flags != REL_WITH)
  53     return 0;
  54   FOR_PROVIDES(p, pp, dep)
  55     {
  56       s = pool->solvables + p;
  57       if (s->repo == solv->installed && s->name == rd->name)
  58         return 1;
  59     }
  60   return 0;
  61 }
  62
  63
  64 /*-------------------------------------------------------------------
  65  * solver_dep_installed
  66  */
  67
  68 int
  69 solver_dep_installed(Solver *solv, Id dep)
  70 {
  71 #if 0
  72   Pool *pool = solv->pool;
  73   Id p, pp;
  74
  75   if (ISRELDEP(dep))
  76     {
  77       Reldep *rd = GETRELDEP(pool, dep);
  78       if (rd->flags == REL_AND)
  79         {
  80           if (!solver_dep_installed(solv, rd->name))
  81             return 0;
  82           return solver_dep_installed(solv, rd->evr);
  83         }
  84       if (rd->flags == REL_NAMESPACE && rd->name == NAMESPACE_INSTALLED)
  85         return solver_dep_installed(solv, rd->evr);
  86     }
  87   FOR_PROVIDES(p, pp, dep)
  88     {
  89       if (p == SYSTEMSOLVABLE || (solv->installed && pool->solvables[p].repo == solv->installed))
  90         return 1;
  91     }
  92 #endif
  93   return 0;
  94 }
  95
  96
  97
  98 /************************************************************************/
  99
 100 /*
 101  * make assertion rules into decisions
 102  *
 103  * Go through rules and add direct assertions to the decisionqueue.
 104  * If we find a conflict, disable rules and add them to problem queue.
 105  */
 106
 107 static void
 108 makeruledecisions(Solver *solv)
 109 {
 110   Pool *pool = solv->pool;
 111   int i, ri, ii;
 112   Rule *r, *rr;
 113   Id v, vv;
 114   int decisionstart;
 115
 116   POOL_DEBUG(SAT_DEBUG_SCHUBI, "----- makeruledecisions ; size decisionq: %d -----\n",solv->decisionq.count);
 117
 118   /* The system solvable is always installed first */
 119   assert(solv->decisionq.count == 0);
 120   queue_push(&solv->decisionq, SYSTEMSOLVABLE);
 121   queue_push(&solv->decisionq_why, 0);
 122   solv->decisionmap[SYSTEMSOLVABLE] = 1;        /* installed at level '1' */
 123
 124   decisionstart = solv->decisionq.count;
 125   for (ii = 0; ii < solv->ruleassertions.count; ii++)
 126     {
 127       ri = solv->ruleassertions.elements[ii];
 128       r = solv->rules + ri;
 129
 130       if (r->d < 0 || !r->p || r->w2)   /* disabled, dummy or no assertion */
 131         continue;
 132       /* do weak rules in phase 2 */
 133       if (ri < solv->learntrules && MAPTST(&solv->weakrulemap, ri))
 134         continue;
 135
 136       v = r->p;
 137       vv = v > 0 ? v : -v;
 138
 139       if (!solv->decisionmap[vv])          /* if not yet decided */
 140         {
 141             /*
 142              * decide !
 143              */
 144           queue_push(&solv->decisionq, v);
 145           queue_push(&solv->decisionq_why, r - solv->rules);
 146           solv->decisionmap[vv] = v > 0 ? 1 : -1;
 147           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 148             {
 149               Solvable *s = solv->pool->solvables + vv;
 150               if (v < 0)
 151                 POOL_DEBUG(SAT_DEBUG_PROPAGATE, "conflicting %s (assertion)\n", solvable2str(solv->pool, s));
 152               else
 153                 POOL_DEBUG(SAT_DEBUG_PROPAGATE, "installing  %s (assertion)\n", solvable2str(solv->pool, s));
 154             }
 155           continue;
 156         }
 157         /*
 158          * check previous decision: is it sane ?
 159          */
 160
 161       if (v > 0 && solv->decisionmap[vv] > 0)    /* ok to install */
 162         continue;
 163       if (v < 0 && solv->decisionmap[vv] < 0)    /* ok to remove */
 164         continue;
 165
 166         /*
 167          * found a conflict!
 168          *
 169          * The rule (r) we're currently processing says something
 170          * different (v = r->p) than a previous decision (decisionmap[abs(v)])
 171          * on this literal
 172          */
 173
 174       if (ri >= solv->learntrules)
 175         {
 176           /* conflict with a learnt rule */
 177           /* can happen when packages cannot be installed for
 178            * multiple reasons. */
 179           /* we disable the learnt rule in this case */
 180           solver_disablerule(solv, r);
 181           continue;
 182         }
 183
 184         /*
 185          * find the decision which is the "opposite" of the rule
 186          */
 187
 188       for (i = 0; i < solv->decisionq.count; i++)
 189         if (solv->decisionq.elements[i] == -v)
 190           break;
 191       assert(i < solv->decisionq.count);         /* assert that we found it */
 192
 193       /*
 194        * conflict with system solvable ?
 195        */
 196
 197       if (v == -SYSTEMSOLVABLE) {
 198         /* conflict with system solvable */
 199         queue_push(&solv->problems, solv->learnt_pool.count);
 200         queue_push(&solv->learnt_pool, ri);
 201         queue_push(&solv->learnt_pool, 0);
 202         POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "conflict with system solvable, disabling rule #%d\n", ri);
 203         if  (ri >= solv->jobrules && ri < solv->jobrules_end)
 204           v = -(solv->ruletojob.elements[ri - solv->jobrules] + 1);
 205         else
 206           v = ri;
 207         queue_push(&solv->problems, v);
 208         queue_push(&solv->problems, 0);
 209         solver_disableproblem(solv, v);
 210         continue;
 211       }
 212
 213       assert(solv->decisionq_why.elements[i] > 0);
 214
 215       /*
 216        * conflict with an rpm rule ?
 217        */
 218
 219       if (solv->decisionq_why.elements[i] < solv->rpmrules_end)
 220         {
 221           /* conflict with rpm rule assertion */
 222           queue_push(&solv->problems, solv->learnt_pool.count);
 223           queue_push(&solv->learnt_pool, ri);
 224           queue_push(&solv->learnt_pool, solv->decisionq_why.elements[i]);
 225           queue_push(&solv->learnt_pool, 0);
 226           assert(v > 0 || v == -SYSTEMSOLVABLE);
 227           POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "conflict with rpm rule, disabling rule #%d\n", ri);
 228           if (ri >= solv->jobrules && ri < solv->jobrules_end)
 229             v = -(solv->ruletojob.elements[ri - solv->jobrules] + 1);
 230           else
 231             v = ri;
 232           queue_push(&solv->problems, v);
 233           queue_push(&solv->problems, 0);
 234           solver_disableproblem(solv, v);
 235           continue;
 236         }
 237
 238       /*
 239        * conflict with another job or update/feature rule
 240        */
 241
 242       /* record proof */
 243       queue_push(&solv->problems, solv->learnt_pool.count);
 244       queue_push(&solv->learnt_pool, ri);
 245       queue_push(&solv->learnt_pool, solv->decisionq_why.elements[i]);
 246       queue_push(&solv->learnt_pool, 0);
 247
 248       POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "conflicting update/job assertions over literal %d\n", vv);
 249
 250         /*
 251          * push all of our rules (can only be feature or job rules)
 252          * asserting this literal on the problem stack
 253          */
 254
 255       for (i = solv->featurerules, rr = solv->rules + i; i < solv->learntrules; i++, rr++)
 256         {
 257           if (rr->d < 0                          /* disabled */
 258               || rr->w2)                         /*  or no assertion */
 259             continue;
 260           if (rr->p != vv                        /* not affecting the literal */
 261               && rr->p != -vv)
 262             continue;
 263           if (MAPTST(&solv->weakrulemap, i))     /* weak: silently ignore */
 264             continue;
 265
 266           POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, " - disabling rule #%d\n", i);
 267
 268           solver_printruleclass(solv, SAT_DEBUG_UNSOLVABLE, solv->rules + i);
 269
 270           v = i;
 271             /* is is a job rule ? */
 272           if (i >= solv->jobrules && i < solv->jobrules_end)
 273             v = -(solv->ruletojob.elements[i - solv->jobrules] + 1);
 274
 275           queue_push(&solv->problems, v);
 276           solver_disableproblem(solv, v);
 277         }
 278       queue_push(&solv->problems, 0);
 279
 280       /*
 281        * start over
 282        * (back up from decisions)
 283        */
 284       while (solv->decisionq.count > decisionstart)
 285         {
 286           v = solv->decisionq.elements[--solv->decisionq.count];
 287           --solv->decisionq_why.count;
 288           vv = v > 0 ? v : -v;
 289           solv->decisionmap[vv] = 0;
 290         }
 291       ii = -1; /* restarts loop at 0 */
 292     }
 293
 294   /*
 295    * phase 2: now do the weak assertions
 296    */
 297   for (ii = 0; ii < solv->ruleassertions.count; ii++)
 298     {
 299       ri = solv->ruleassertions.elements[ii];
 300       r = solv->rules + ri;
 301       if (r->d < 0 || r->w2)                     /* disabled or no assertion */
 302         continue;
 303       if (ri >= solv->learntrules || !MAPTST(&solv->weakrulemap, ri))       /* skip non-weak */
 304         continue;
 305       v = r->p;
 306       vv = v > 0 ? v : -v;
 307       /*
 308        * decide !
 309        * (if not yet decided)
 310        */
 311       if (!solv->decisionmap[vv])
 312         {
 313           queue_push(&solv->decisionq, v);
 314           queue_push(&solv->decisionq_why, r - solv->rules);
 315           solv->decisionmap[vv] = v > 0 ? 1 : -1;
 316           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 317             {
 318               Solvable *s = solv->pool->solvables + vv;
 319               if (v < 0)
 320                 POOL_DEBUG(SAT_DEBUG_PROPAGATE, "conflicting %s (weak assertion)\n", solvable2str(solv->pool, s));
 321               else
 322                 POOL_DEBUG(SAT_DEBUG_PROPAGATE, "installing  %s (weak assertion)\n", solvable2str(solv->pool, s));
 323             }
 324           continue;
 325         }
 326       /*
 327        * previously decided, sane ?
 328        */
 329       if (v > 0 && solv->decisionmap[vv] > 0)
 330         continue;
 331       if (v < 0 && solv->decisionmap[vv] < 0)
 332         continue;
 333
 334       POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "assertion conflict, but I am weak, disabling ");
 335       solver_printrule(solv, SAT_DEBUG_UNSOLVABLE, r);
 336
 337       if (ri >= solv->jobrules && ri < solv->jobrules_end)
 338         v = -(solv->ruletojob.elements[ri - solv->jobrules] + 1);
 339       else
 340         v = ri;
 341       solver_disableproblem(solv, v);
 342       if (v < 0)
 343         solver_reenablepolicyrules(solv, -(v + 1));
 344     }
 345
 346   POOL_DEBUG(SAT_DEBUG_SCHUBI, "----- makeruledecisions end; size decisionq: %d -----\n",solv->decisionq.count);
 347 }
 348
 349
 350 /*-------------------------------------------------------------------
 351  * enable/disable learnt rules
 352  *
 353  * we have enabled or disabled some of our rules. We now reenable all
 354  * of our learnt rules except the ones that were learnt from rules that
 355  * are now disabled.
 356  */
 357 static void
 358 enabledisablelearntrules(Solver *solv)
 359 {
 360   Pool *pool = solv->pool;
 361   Rule *r;
 362   Id why, *whyp;
 363   int i;
 364
 365   POOL_DEBUG(SAT_DEBUG_SOLUTIONS, "enabledisablelearntrules called\n");
 366   for (i = solv->learntrules, r = solv->rules + i; i < solv->nrules; i++, r++)
 367     {
 368       whyp = solv->learnt_pool.elements + solv->learnt_why.elements[i - solv->learntrules];
 369       while ((why = *whyp++) != 0)
 370         {
 371           assert(why > 0 && why < i);
 372           if (solv->rules[why].d < 0)
 373             break;
 374         }
 375       /* why != 0: we found a disabled rule, disable the learnt rule */
 376       if (why && r->d >= 0)
 377         {
 378           IF_POOLDEBUG (SAT_DEBUG_SOLUTIONS)
 379             {
 380               POOL_DEBUG(SAT_DEBUG_SOLUTIONS, "disabling ");
 381               solver_printruleclass(solv, SAT_DEBUG_SOLUTIONS, r);
 382             }
 383           solver_disablerule(solv, r);
 384         }
 385       else if (!why && r->d < 0)
 386         {
 387           IF_POOLDEBUG (SAT_DEBUG_SOLUTIONS)
 388             {
 389               POOL_DEBUG(SAT_DEBUG_SOLUTIONS, "re-enabling ");
 390               solver_printruleclass(solv, SAT_DEBUG_SOLUTIONS, r);
 391             }
 392           solver_enablerule(solv, r);
 393         }
 394     }
 395 }
 396
 397
 398 /********************************************************************/
 399 /* watches */
 400
 401
 402 /*-------------------------------------------------------------------
 403  * makewatches
 404  *
 405  * initial setup for all watches
 406  */
 407
 408 static void
 409 makewatches(Solver *solv)
 410 {
 411   Rule *r;
 412   int i;
 413   int nsolvables = solv->pool->nsolvables;
 414
 415   sat_free(solv->watches);
 416                                        /* lower half for removals, upper half for installs */
 417   solv->watches = sat_calloc(2 * nsolvables, sizeof(Id));
 418 #if 1
 419   /* do it reverse so rpm rules get triggered first (XXX: obsolete?) */
 420   for (i = 1, r = solv->rules + solv->nrules - 1; i < solv->nrules; i++, r--)
 421 #else
 422   for (i = 1, r = solv->rules + 1; i < solv->nrules; i++, r++)
 423 #endif
 424     {
 425       if (!r->w2)               /* assertions do not need watches */
 426         continue;
 427
 428       /* see addwatches_rule(solv, r) */
 429       r->n1 = solv->watches[nsolvables + r->w1];
 430       solv->watches[nsolvables + r->w1] = r - solv->rules;
 431
 432       r->n2 = solv->watches[nsolvables + r->w2];
 433       solv->watches[nsolvables + r->w2] = r - solv->rules;
 434     }
 435 }
 436
 437
 438 /*-------------------------------------------------------------------
 439  *
 440  * add watches (for a new learned rule)
 441  * sets up watches for a single rule
 442  *
 443  * see also makewatches() above.
 444  */
 445
 446 static inline void
 447 addwatches_rule(Solver *solv, Rule *r)
 448 {
 449   int nsolvables = solv->pool->nsolvables;
 450
 451   r->n1 = solv->watches[nsolvables + r->w1];
 452   solv->watches[nsolvables + r->w1] = r - solv->rules;
 453
 454   r->n2 = solv->watches[nsolvables + r->w2];
 455   solv->watches[nsolvables + r->w2] = r - solv->rules;
 456 }
 457
 458
 459 /********************************************************************/
 460 /*
 461  * rule propagation
 462  */
 463
 464
 465 /* shortcuts to check if a literal (positive or negative) assignment
 466  * evaluates to 'true' or 'false'
 467  */
 468 #define DECISIONMAP_TRUE(p) ((p) > 0 ? (decisionmap[p] > 0) : (decisionmap[-p] < 0))
 469 #define DECISIONMAP_FALSE(p) ((p) > 0 ? (decisionmap[p] < 0) : (decisionmap[-p] > 0))
 470 #define DECISIONMAP_UNDEF(p) (decisionmap[(p) > 0 ? (p) : -(p)] == 0)
 471
 472 /*-------------------------------------------------------------------
 473  *
 474  * propagate
 475  *
 476  * make decision and propagate to all rules
 477  *
 478  * Evaluate each term affected by the decision (linked through watches)
 479  * If we find unit rules we make new decisions based on them
 480  *
 481  * Everything's fixed there, it's just finding rules that are
 482  * unit.
 483  *
 484  * return : 0 = everything is OK
 485  *          rule = conflict found in this rule
 486  */
 487
 488 static Rule *
 489 propagate(Solver *solv, int level)
 490 {
 491   Pool *pool = solv->pool;
 492   Id *rp, *next_rp;           /* rule pointer, next rule pointer in linked list */
 493   Rule *r;                    /* rule */
 494   Id p, pkg, other_watch;
 495   Id *dp;
 496   Id *decisionmap = solv->decisionmap;
 497
 498   Id *watches = solv->watches + pool->nsolvables;   /* place ptr in middle */
 499
 500   POOL_DEBUG(SAT_DEBUG_PROPAGATE, "----- propagate -----\n");
 501
 502   /* foreach non-propagated decision */
 503   while (solv->propagate_index < solv->decisionq.count)
 504     {
 505         /*
 506          * 'pkg' was just decided
 507          * negate because our watches trigger if literal goes FALSE
 508          */
 509       pkg = -solv->decisionq.elements[solv->propagate_index++];
 510
 511       IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 512         {
 513           POOL_DEBUG(SAT_DEBUG_PROPAGATE, "propagate for decision %d level %d\n", -pkg, level);
 514           solver_printruleelement(solv, SAT_DEBUG_PROPAGATE, 0, -pkg);
 515         }
 516
 517       /* foreach rule where 'pkg' is now FALSE */
 518       for (rp = watches + pkg; *rp; rp = next_rp)
 519         {
 520           r = solv->rules + *rp;
 521           if (r->d < 0)
 522             {
 523               /* rule is disabled, goto next */
 524               if (pkg == r->w1)
 525                 next_rp = &r->n1;
 526               else
 527                 next_rp = &r->n2;
 528               continue;
 529             }
 530
 531           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 532             {
 533               POOL_DEBUG(SAT_DEBUG_PROPAGATE,"  watch triggered ");
 534               solver_printrule(solv, SAT_DEBUG_PROPAGATE, r);
 535             }
 536
 537             /* 'pkg' was just decided (was set to FALSE)
 538              *
 539              *  now find other literal watch, check clause
 540              *   and advance on linked list
 541              */
 542           if (pkg == r->w1)
 543             {
 544               other_watch = r->w2;
 545               next_rp = &r->n1;
 546             }
 547           else
 548             {
 549               other_watch = r->w1;
 550               next_rp = &r->n2;
 551             }
 552
 553             /*
 554              * This term is already true (through the other literal)
 555              * so we have nothing to do
 556              */
 557           if (DECISIONMAP_TRUE(other_watch))
 558             continue;
 559
 560             /*
 561              * The other literal is FALSE or UNDEF
 562              *
 563              */
 564
 565           if (r->d)
 566             {
 567               /* Not a binary clause, try to move our watch.
 568                *
 569                * Go over all literals and find one that is
 570                *   not other_watch
 571                *   and not FALSE
 572                *
 573                * (TRUE is also ok, in that case the rule is fulfilled)
 574                */
 575               if (r->p                                /* we have a 'p' */
 576                   && r->p != other_watch              /* which is not watched */
 577                   && !DECISIONMAP_FALSE(r->p))        /* and not FALSE */
 578                 {
 579                   p = r->p;
 580                 }
 581               else                                    /* go find a 'd' to make 'true' */
 582                 {
 583                   /* foreach p in 'd'
 584                      we just iterate sequentially, doing it in another order just changes the order of decisions, not the decisions itself
 585                    */
 586                   for (dp = pool->whatprovidesdata + r->d; (p = *dp++) != 0;)
 587                     {
 588                       if (p != other_watch              /* which is not watched */
 589                           && !DECISIONMAP_FALSE(p))     /* and not FALSE */
 590                         break;
 591                     }
 592                 }
 593
 594               if (p)
 595                 {
 596                   /*
 597                    * if we found some p that is UNDEF or TRUE, move
 598                    * watch to it
 599                    */
 600                   IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 601                     {
 602                       if (p > 0)
 603                         POOL_DEBUG(SAT_DEBUG_PROPAGATE, "    -> move w%d to %s\n", (pkg == r->w1 ? 1 : 2), solvid2str(pool, p));
 604                       else
 605                         POOL_DEBUG(SAT_DEBUG_PROPAGATE,"    -> move w%d to !%s\n", (pkg == r->w1 ? 1 : 2), solvid2str(pool, -p));
 606                     }
 607
 608                   *rp = *next_rp;
 609                   next_rp = rp;
 610
 611                   if (pkg == r->w1)
 612                     {
 613                       r->w1 = p;
 614                       r->n1 = watches[p];
 615                     }
 616                   else
 617                     {
 618                       r->w2 = p;
 619                       r->n2 = watches[p];
 620                     }
 621                   watches[p] = r - solv->rules;
 622                   continue;
 623                 }
 624               /* search failed, thus all unwatched literals are FALSE */
 625
 626             } /* not binary */
 627
 628             /*
 629              * unit clause found, set literal other_watch to TRUE
 630              */
 631
 632           if (DECISIONMAP_FALSE(other_watch))      /* check if literal is FALSE */
 633             return r;                              /* eek, a conflict! */
 634
 635           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 636             {
 637               POOL_DEBUG(SAT_DEBUG_PROPAGATE, "   unit ");
 638               solver_printrule(solv, SAT_DEBUG_PROPAGATE, r);
 639             }
 640
 641           if (other_watch > 0)
 642             decisionmap[other_watch] = level;    /* install! */
 643           else
 644             decisionmap[-other_watch] = -level;  /* remove! */
 645
 646           queue_push(&solv->decisionq, other_watch);
 647           queue_push(&solv->decisionq_why, r - solv->rules);
 648
 649           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
 650             {
 651               if (other_watch > 0)
 652                 POOL_DEBUG(SAT_DEBUG_PROPAGATE, "    -> decided to install %s\n", solvid2str(pool, other_watch));
 653               else
 654                 POOL_DEBUG(SAT_DEBUG_PROPAGATE, "    -> decided to conflict %s\n", solvid2str(pool, -other_watch));
 655             }
 656
 657         } /* foreach rule involving 'pkg' */
 658
 659     } /* while we have non-decided decisions */
 660
 661   POOL_DEBUG(SAT_DEBUG_PROPAGATE, "----- propagate end-----\n");
 662
 663   return 0;     /* all is well */
 664 }
 665
 666
 667 /********************************************************************/
 668 /* Analysis */
 669
 670 /*-------------------------------------------------------------------
 671  *
 672  * analyze
 673  *   and learn
 674  */
 675
 676 static int
 677 analyze(Solver *solv, int level, Rule *c, int *pr, int *dr, int *whyp)
 678 {
 679   Pool *pool = solv->pool;
 680   Queue r;
 681   int rlevel = 1;
 682   Map seen;             /* global? */
 683   Id d, v, vv, *dp, why;
 684   int l, i, idx;
 685   int num = 0, l1num = 0;
 686   int learnt_why = solv->learnt_pool.count;
 687   Id *decisionmap = solv->decisionmap;
 688
 689   queue_init(&r);
 690
 691   POOL_DEBUG(SAT_DEBUG_ANALYZE, "ANALYZE at %d ----------------------\n", level);
 692   map_init(&seen, pool->nsolvables);
 693   idx = solv->decisionq.count;
 694   for (;;)
 695     {
 696       IF_POOLDEBUG (SAT_DEBUG_ANALYZE)
 697         solver_printruleclass(solv, SAT_DEBUG_ANALYZE, c);
 698       queue_push(&solv->learnt_pool, c - solv->rules);
 699       d = c->d < 0 ? -c->d - 1 : c->d;
 700       dp = d ? pool->whatprovidesdata + d : 0;
 701       /* go through all literals of the rule */
 702       for (i = -1; ; i++)
 703         {
 704           if (i == -1)
 705             v = c->p;
 706           else if (d == 0)
 707             v = i ? 0 : c->w2;
 708           else
 709             v = *dp++;
 710           if (v == 0)
 711             break;
 712
 713           if (DECISIONMAP_TRUE(v))      /* the one true literal */
 714             continue;
 715           vv = v > 0 ? v : -v;
 716           if (MAPTST(&seen, vv))
 717             continue;
 718           l = solv->decisionmap[vv];
 719           if (l < 0)
 720             l = -l;
 721           MAPSET(&seen, vv);
 722           if (l == 1)
 723             l1num++;                    /* need to do this one in level1 pass */
 724           else if (l == level)
 725             num++;                      /* need to do this one as well */
 726           else
 727             {
 728               queue_push(&r, v);        /* not level1 or conflict level, add to new rule */
 729               if (l > rlevel)
 730                 rlevel = l;
 731             }
 732         }
 733 l1retry:
 734       if (!num && !--l1num)
 735         break;  /* all level 1 literals done */
 736       for (;;)
 737         {
 738           assert(idx > 0);
 739           v = solv->decisionq.elements[--idx];
 740           vv = v > 0 ? v : -v;
 741           if (MAPTST(&seen, vv))
 742             break;
 743         }
 744       MAPCLR(&seen, vv);
 745       if (num && --num == 0)
 746         {
 747           *pr = -v;     /* so that v doesn't get lost */
 748           if (!l1num)
 749             break;
 750           POOL_DEBUG(SAT_DEBUG_ANALYZE, "got %d involved level 1 decisions\n", l1num);
 751           for (i = 0; i < r.count; i++)
 752             {
 753               v = r.elements[i];
 754               MAPCLR(&seen, v > 0 ? v : -v);
 755             }
 756           /* only level 1 marks left */
 757           l1num++;
 758           goto l1retry;
 759         }
 760       why = solv->decisionq_why.elements[idx];
 761       if (why <= 0)     /* just in case, maybe for SYSTEMSOLVABLE */
 762         goto l1retry;
 763       c = solv->rules + why;
 764     }
 765   map_free(&seen);
 766
 767   if (r.count == 0)
 768     *dr = 0;
 769   else if (r.count == 1 && r.elements[0] < 0)
 770     *dr = r.elements[0];
 771   else
 772     *dr = pool_queuetowhatprovides(pool, &r);
 773   IF_POOLDEBUG (SAT_DEBUG_ANALYZE)
 774     {
 775       POOL_DEBUG(SAT_DEBUG_ANALYZE, "learned rule for level %d (am %d)\n", rlevel, level);
 776       solver_printruleelement(solv, SAT_DEBUG_ANALYZE, 0, *pr);
 777       for (i = 0; i < r.count; i++)
 778         solver_printruleelement(solv, SAT_DEBUG_ANALYZE, 0, r.elements[i]);
 779     }
 780   /* push end marker on learnt reasons stack */
 781   queue_push(&solv->learnt_pool, 0);
 782   if (whyp)
 783     *whyp = learnt_why;
 784   solv->stats_learned++;
 785   return rlevel;
 786 }
 787
 788
 789 /*-------------------------------------------------------------------
 790  *
 791  * solver_reset
 792  *
 793  * reset the solver decisions to right after the rpm rules.
 794  * called after rules have been enabled/disabled
 795  */
 796
 797 void
 798 solver_reset(Solver *solv)
 799 {
 800   Pool *pool = solv->pool;
 801   int i;
 802   Id v;
 803
 804   /* rewind all decisions */
 805   for (i = solv->decisionq.count - 1; i >= 0; i--)
 806     {
 807       v = solv->decisionq.elements[i];
 808       solv->decisionmap[v > 0 ? v : -v] = 0;
 809     }
 810   solv->decisionq_why.count = 0;
 811   solv->decisionq.count = 0;
 812   solv->recommends_index = -1;
 813   solv->propagate_index = 0;
 814   solv->recommendations.count = 0;
 815   solv->branches.count = 0;
 816
 817   /* adapt learnt rule status to new set of enabled/disabled rules */
 818   enabledisablelearntrules(solv);
 819
 820   /* redo all job/update decisions */
 821   makeruledecisions(solv);
 822   POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "decisions so far: %d\n", solv->decisionq.count);
 823 }
 824
 825
 826 /*-------------------------------------------------------------------
 827  *
 828  * analyze_unsolvable_rule
 829  */
 830
 831 static void
 832 analyze_unsolvable_rule(Solver *solv, Rule *r, Id *lastweakp)
 833 {
 834   Pool *pool = solv->pool;
 835   int i;
 836   Id why = r - solv->rules;
 837
 838   IF_POOLDEBUG (SAT_DEBUG_UNSOLVABLE)
 839     solver_printruleclass(solv, SAT_DEBUG_UNSOLVABLE, r);
 840   if (solv->learntrules && why >= solv->learntrules)
 841     {
 842       for (i = solv->learnt_why.elements[why - solv->learntrules]; solv->learnt_pool.elements[i]; i++)
 843         if (solv->learnt_pool.elements[i] > 0)
 844           analyze_unsolvable_rule(solv, solv->rules + solv->learnt_pool.elements[i], lastweakp);
 845       return;
 846     }
 847   if (MAPTST(&solv->weakrulemap, why))
 848     if (!*lastweakp || why > *lastweakp)
 849       *lastweakp = why;
 850   /* do not add rpm rules to problem */
 851   if (why < solv->rpmrules_end)
 852     return;
 853   /* turn rule into problem */
 854   if (why >= solv->jobrules && why < solv->jobrules_end)
 855     why = -(solv->ruletojob.elements[why - solv->jobrules] + 1);
 856   /* normalize dup/infarch rules */
 857   if (why > solv->infarchrules && why < solv->infarchrules_end)
 858     {
 859       Id name = pool->solvables[-solv->rules[why].p].name;
 860       while (why > solv->infarchrules && pool->solvables[-solv->rules[why - 1].p].name == name)
 861         why--;
 862     }
 863   if (why > solv->duprules && why < solv->duprules_end)
 864     {
 865       Id name = pool->solvables[-solv->rules[why].p].name;
 866       while (why > solv->duprules && pool->solvables[-solv->rules[why - 1].p].name == name)
 867         why--;
 868     }
 869
 870   /* return if problem already countains our rule */
 871   if (solv->problems.count)
 872     {
 873       for (i = solv->problems.count - 1; i >= 0; i--)
 874         if (solv->problems.elements[i] == 0)    /* end of last problem reached? */
 875           break;
 876         else if (solv->problems.elements[i] == why)
 877           return;
 878     }
 879   queue_push(&solv->problems, why);
 880 }
 881
 882
 883 /*-------------------------------------------------------------------
 884  *
 885  * analyze_unsolvable
 886  *
 887  * return: 1 - disabled some rules, try again
 888  *         0 - hopeless
 889  */
 890
 891 static int
 892 analyze_unsolvable(Solver *solv, Rule *cr, int disablerules)
 893 {
 894   Pool *pool = solv->pool;
 895   Rule *r;
 896   Map seen;             /* global to speed things up? */
 897   Id d, v, vv, *dp, why;
 898   int l, i, idx;
 899   Id *decisionmap = solv->decisionmap;
 900   int oldproblemcount;
 901   int oldlearntpoolcount;
 902   Id lastweak;
 903
 904   POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "ANALYZE UNSOLVABLE ----------------------\n");
 905   solv->stats_unsolvable++;
 906   oldproblemcount = solv->problems.count;
 907   oldlearntpoolcount = solv->learnt_pool.count;
 908
 909   /* make room for proof index */
 910   /* must update it later, as analyze_unsolvable_rule would confuse
 911    * it with a rule index if we put the real value in already */
 912   queue_push(&solv->problems, 0);
 913
 914   r = cr;
 915   map_init(&seen, pool->nsolvables);
 916   queue_push(&solv->learnt_pool, r - solv->rules);
 917   lastweak = 0;
 918   analyze_unsolvable_rule(solv, r, &lastweak);
 919   d = r->d < 0 ? -r->d - 1 : r->d;
 920   dp = d ? pool->whatprovidesdata + d : 0;
 921   for (i = -1; ; i++)
 922     {
 923       if (i == -1)
 924         v = r->p;
 925       else if (d == 0)
 926         v = i ? 0 : r->w2;
 927       else
 928         v = *dp++;
 929       if (v == 0)
 930         break;
 931       if (DECISIONMAP_TRUE(v))  /* the one true literal */
 932           continue;
 933       vv = v > 0 ? v : -v;
 934       l = solv->decisionmap[vv];
 935       if (l < 0)
 936         l = -l;
 937       MAPSET(&seen, vv);
 938     }
 939   idx = solv->decisionq.count;
 940   while (idx > 0)
 941     {
 942       v = solv->decisionq.elements[--idx];
 943       vv = v > 0 ? v : -v;
 944       if (!MAPTST(&seen, vv))
 945         continue;
 946       why = solv->decisionq_why.elements[idx];
 947       assert(why > 0);
 948       queue_push(&solv->learnt_pool, why);
 949       r = solv->rules + why;
 950       analyze_unsolvable_rule(solv, r, &lastweak);
 951       d = r->d < 0 ? -r->d - 1 : r->d;
 952       dp = d ? pool->whatprovidesdata + d : 0;
 953       for (i = -1; ; i++)
 954         {
 955           if (i == -1)
 956             v = r->p;
 957           else if (d == 0)
 958             v = i ? 0 : r->w2;
 959           else
 960             v = *dp++;
 961           if (v == 0)
 962             break;
 963           if (DECISIONMAP_TRUE(v))      /* the one true literal */
 964               continue;
 965           vv = v > 0 ? v : -v;
 966           l = solv->decisionmap[vv];
 967           if (l < 0)
 968             l = -l;
 969           MAPSET(&seen, vv);
 970         }
 971     }
 972   map_free(&seen);
 973   queue_push(&solv->problems, 0);       /* mark end of this problem */
 974
 975   if (lastweak)
 976     {
 977       Id v;
 978       extern void disablechoicerules(Solver *solv, Rule *r);
 979       /* disable last weak rule */
 980       solv->problems.count = oldproblemcount;
 981       solv->learnt_pool.count = oldlearntpoolcount;
 982       if (lastweak >= solv->jobrules && lastweak < solv->jobrules_end)
 983         v = -(solv->ruletojob.elements[lastweak - solv->jobrules] + 1);
 984       else
 985         v = lastweak;
 986       POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "disabling ");
 987       solver_printruleclass(solv, SAT_DEBUG_UNSOLVABLE, solv->rules + lastweak);
 988       if (lastweak >= solv->choicerules && lastweak < solv->choicerules_end)
 989         disablechoicerules(solv, solv->rules + lastweak);
 990       solver_disableproblem(solv, v);
 991       if (v < 0)
 992         solver_reenablepolicyrules(solv, -(v + 1));
 993       solver_reset(solv);
 994       return 1;
 995     }
 996
 997   /* finish proof */
 998   queue_push(&solv->learnt_pool, 0);
 999   solv->problems.elements[oldproblemcount] = oldlearntpoolcount;
1000
1001   if (disablerules)
1002     {
1003       for (i = oldproblemcount + 1; i < solv->problems.count - 1; i++)
1004         solver_disableproblem(solv, solv->problems.elements[i]);
1005       /* XXX: might want to enable all weak rules again */
1006       solver_reset(solv);
1007       return 1;
1008     }
1009   POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "UNSOLVABLE\n");
1010   return 0;
1011 }
1012
1013
1014 /********************************************************************/
1015 /* Decision revert */
1016
1017 /*-------------------------------------------------------------------
1018  *
1019  * revert
1020  * revert decision at level
1021  */
1022
1023 static void
1024 revert(Solver *solv, int level)
1025 {
1026   Pool *pool = solv->pool;
1027   Id v, vv;
1028   while (solv->decisionq.count)
1029     {
1030       v = solv->decisionq.elements[solv->decisionq.count - 1];
1031       vv = v > 0 ? v : -v;
1032       if (solv->decisionmap[vv] <= level && solv->decisionmap[vv] >= -level)
1033         break;
1034       POOL_DEBUG(SAT_DEBUG_PROPAGATE, "reverting decision %d at %d\n", v, solv->decisionmap[vv]);
1035       if (v > 0 && solv->recommendations.count && v == solv->recommendations.elements[solv->recommendations.count - 1])
1036         solv->recommendations.count--;
1037       solv->decisionmap[vv] = 0;
1038       solv->decisionq.count--;
1039       solv->decisionq_why.count--;
1040       solv->propagate_index = solv->decisionq.count;
1041     }
1042   while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] <= -level)
1043     {
1044       solv->branches.count--;
1045       while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] >= 0)
1046         solv->branches.count--;
1047     }
1048   solv->recommends_index = -1;
1049 }
1050
1051
1052 /*-------------------------------------------------------------------
1053  *
1054  * watch2onhighest - put watch2 on literal with highest level
1055  */
1056
1057 static inline void
1058 watch2onhighest(Solver *solv, Rule *r)
1059 {
1060   int l, wl = 0;
1061   Id d, v, *dp;
1062
1063   d = r->d < 0 ? -r->d - 1 : r->d;
1064   if (!d)
1065     return;     /* binary rule, both watches are set */
1066   dp = solv->pool->whatprovidesdata + d;
1067   while ((v = *dp++) != 0)
1068     {
1069       l = solv->decisionmap[v < 0 ? -v : v];
1070       if (l < 0)
1071         l = -l;
1072       if (l > wl)
1073         {
1074           r->w2 = dp[-1];
1075           wl = l;
1076         }
1077     }
1078 }
1079
1080
1081 /*-------------------------------------------------------------------
1082  *
1083  * setpropagatelearn
1084  *
1085  * add free decision (solvable to install) to decisionq
1086  * increase level and propagate decision
1087  * return if no conflict.
1088  *
1089  * in conflict case, analyze conflict rule, add resulting
1090  * rule to learnt rule set, make decision from learnt
1091  * rule (always unit) and re-propagate.
1092  *
1093  * returns the new solver level or 0 if unsolvable
1094  *
1095  */
1096
1097 static int
1098 setpropagatelearn(Solver *solv, int level, Id decision, int disablerules, Id ruleid)
1099 {
1100   Pool *pool = solv->pool;
1101   Rule *r;
1102   Id p = 0, d = 0;
1103   int l, why;
1104
1105   assert(ruleid >= 0);
1106   if (decision)
1107     {
1108       level++;
1109       if (decision > 0)
1110         solv->decisionmap[decision] = level;
1111       else
1112         solv->decisionmap[-decision] = -level;
1113       queue_push(&solv->decisionq, decision);
1114       queue_push(&solv->decisionq_why, -ruleid);        /* <= 0 -> free decision */
1115     }
1116   for (;;)
1117     {
1118       r = propagate(solv, level);
1119       if (!r)
1120         break;
1121       if (level == 1)
1122         return analyze_unsolvable(solv, r, disablerules);
1123       POOL_DEBUG(SAT_DEBUG_ANALYZE, "conflict with rule #%d\n", (int)(r - solv->rules));
1124       l = analyze(solv, level, r, &p, &d, &why);        /* learnt rule in p and d */
1125       assert(l > 0 && l < level);
1126       POOL_DEBUG(SAT_DEBUG_ANALYZE, "reverting decisions (level %d -> %d)\n", level, l);
1127       level = l;
1128       revert(solv, level);
1129       r = solver_addrule(solv, p, d);
1130       assert(r);
1131       assert(solv->learnt_why.count == (r - solv->rules) - solv->learntrules);
1132       queue_push(&solv->learnt_why, why);
1133       if (d)
1134         {
1135           /* at least 2 literals, needs watches */
1136           watch2onhighest(solv, r);
1137           addwatches_rule(solv, r);
1138         }
1139       else
1140         {
1141           /* learnt rule is an assertion */
1142           queue_push(&solv->ruleassertions, r - solv->rules);
1143         }
1144       /* the new rule is unit by design */
1145       solv->decisionmap[p > 0 ? p : -p] = p > 0 ? level : -level;
1146       queue_push(&solv->decisionq, p);
1147       queue_push(&solv->decisionq_why, r - solv->rules);
1148       IF_POOLDEBUG (SAT_DEBUG_ANALYZE)
1149         {
1150           POOL_DEBUG(SAT_DEBUG_ANALYZE, "decision: ");
1151           solver_printruleelement(solv, SAT_DEBUG_ANALYZE, 0, p);
1152           POOL_DEBUG(SAT_DEBUG_ANALYZE, "new rule: ");
1153           solver_printrule(solv, SAT_DEBUG_ANALYZE, r);
1154         }
1155     }
1156   return level;
1157 }
1158
1159
1160 /*-------------------------------------------------------------------
1161  *
1162  * select and install
1163  *
1164  * install best package from the queue. We add an extra package, inst, if
1165  * provided. See comment in weak install section.
1166  *
1167  * returns the new solver level or 0 if unsolvable
1168  *
1169  */
1170
1171 static int
1172 selectandinstall(Solver *solv, int level, Queue *dq, int disablerules, Id ruleid)
1173 {
1174   Pool *pool = solv->pool;
1175   Id p;
1176   int i;
1177
1178   if (dq->count > 1)
1179     policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
1180   if (dq->count > 1)
1181     {
1182       /* XXX: didn't we already do that? */
1183       /* XXX: shouldn't we prefer installed packages? */
1184       /* XXX: move to policy.c? */
1185       /* choose the supplemented one */
1186       for (i = 0; i < dq->count; i++)
1187         if (solver_is_supplementing(solv, pool->solvables + dq->elements[i]))
1188           {
1189             dq->elements[0] = dq->elements[i];
1190             dq->count = 1;
1191             break;
1192           }
1193     }
1194   if (dq->count > 1)
1195     {
1196       /* multiple candidates, open a branch */
1197       for (i = 1; i < dq->count; i++)
1198         queue_push(&solv->branches, dq->elements[i]);
1199       queue_push(&solv->branches, -level);
1200     }
1201   p = dq->elements[0];
1202
1203   POOL_DEBUG(SAT_DEBUG_POLICY, "installing %s\n", solvid2str(pool, p));
1204
1205   return setpropagatelearn(solv, level, p, disablerules, ruleid);
1206 }
1207
1208
1209 /********************************************************************/
1210 /* Main solver interface */
1211
1212
1213 /*-------------------------------------------------------------------
1214  *
1215  * solver_create
1216  * create solver structure
1217  *
1218  * pool: all available solvables
1219  * installed: installed Solvables
1220  *
1221  *
1222  * Upon solving, rules are created to flag the Solvables
1223  * of the 'installed' Repo as installed.
1224  */
1225
1226 Solver *
1227 solver_create(Pool *pool)
1228 {
1229   Solver *solv;
1230   solv = (Solver *)sat_calloc(1, sizeof(Solver));
1231   solv->pool = pool;
1232   solv->installed = pool->installed;
1233
1234   transaction_init(&solv->trans, pool);
1235   queue_init(&solv->ruletojob);
1236   queue_init(&solv->decisionq);
1237   queue_init(&solv->decisionq_why);
1238   queue_init(&solv->problems);
1239   queue_init(&solv->suggestions);
1240   queue_init(&solv->recommendations);
1241   queue_init(&solv->orphaned);
1242   queue_init(&solv->learnt_why);
1243   queue_init(&solv->learnt_pool);
1244   queue_init(&solv->branches);
1245   queue_init(&solv->covenantq);
1246   queue_init(&solv->weakruleq);
1247   queue_init(&solv->ruleassertions);
1248
1249   map_init(&solv->recommendsmap, pool->nsolvables);
1250   map_init(&solv->suggestsmap, pool->nsolvables);
1251   map_init(&solv->noupdate, solv->installed ? solv->installed->end - solv->installed->start : 0);
1252   solv->recommends_index = 0;
1253
1254   solv->decisionmap = (Id *)sat_calloc(pool->nsolvables, sizeof(Id));
1255   solv->nrules = 1;
1256   solv->rules = sat_extend_resize(solv->rules, solv->nrules, sizeof(Rule), RULES_BLOCK);
1257   memset(solv->rules, 0, sizeof(Rule));
1258
1259   return solv;
1260 }
1261
1262
1263 /*-------------------------------------------------------------------
1264  *
1265  * solver_free
1266  */
1267
1268 void
1269 solver_free(Solver *solv)
1270 {
1271   transaction_free(&solv->trans);
1272   queue_free(&solv->job);
1273   queue_free(&solv->ruletojob);
1274   queue_free(&solv->decisionq);
1275   queue_free(&solv->decisionq_why);
1276   queue_free(&solv->learnt_why);
1277   queue_free(&solv->learnt_pool);
1278   queue_free(&solv->problems);
1279   queue_free(&solv->solutions);
1280   queue_free(&solv->suggestions);
1281   queue_free(&solv->recommendations);
1282   queue_free(&solv->orphaned);
1283   queue_free(&solv->branches);
1284   queue_free(&solv->covenantq);
1285   queue_free(&solv->weakruleq);
1286   queue_free(&solv->ruleassertions);
1287
1288   map_free(&solv->recommendsmap);
1289   map_free(&solv->suggestsmap);
1290   map_free(&solv->noupdate);
1291   map_free(&solv->weakrulemap);
1292   map_free(&solv->noobsoletes);
1293
1294   map_free(&solv->updatemap);
1295   map_free(&solv->fixmap);
1296   map_free(&solv->dupmap);
1297   map_free(&solv->dupinvolvedmap);
1298
1299   sat_free(solv->decisionmap);
1300   sat_free(solv->rules);
1301   sat_free(solv->watches);
1302   sat_free(solv->obsoletes);
1303   sat_free(solv->obsoletes_data);
1304   sat_free(solv->multiversionupdaters);
1305   sat_free(solv->choicerules_ref);
1306   sat_free(solv);
1307 }
1308
1309
1310 /*-------------------------------------------------------------------
1311  *
1312  * solver_run_sat
1313  *
1314  * all rules have been set up, now actually run the solver
1315  *
1316  */
1317
1318 void
1319 solver_run_sat(Solver *solv, int disablerules, int doweak)
1320 {
1321   Queue dq;             /* local decisionqueue */
1322   Queue dqs;            /* local decisionqueue for supplements */
1323   int systemlevel;
1324   int level, olevel;
1325   Rule *r;
1326   int i, j, n;
1327   Solvable *s;
1328   Pool *pool = solv->pool;
1329   Id p, *dp;
1330   int minimizationsteps;
1331   int installedpos = solv->installed ? solv->installed->start : 0;
1332
1333   IF_POOLDEBUG (SAT_DEBUG_RULE_CREATION)
1334     {
1335       POOL_DEBUG (SAT_DEBUG_RULE_CREATION, "number of rules: %d\n", solv->nrules);
1336       for (i = 1; i < solv->nrules; i++)
1337         solver_printruleclass(solv, SAT_DEBUG_RULE_CREATION, solv->rules + i);
1338     }
1339
1340   POOL_DEBUG(SAT_DEBUG_SOLVER, "initial decisions: %d\n", solv->decisionq.count);
1341
1342   IF_POOLDEBUG (SAT_DEBUG_SCHUBI)
1343     solver_printdecisions(solv);
1344
1345   /* start SAT algorithm */
1346   level = 1;
1347   systemlevel = level + 1;
1348   POOL_DEBUG(SAT_DEBUG_SOLVER, "solving...\n");
1349
1350   queue_init(&dq);
1351   queue_init(&dqs);
1352
1353   /*
1354    * here's the main loop:
1355    * 1) propagate new decisions (only needed for level 1)
1356    * 2) try to keep installed packages
1357    * 3) fulfill all unresolved rules
1358    * 4) install recommended packages
1359    * 5) minimalize solution if we had choices
1360    * if we encounter a problem, we rewind to a safe level and restart
1361    * with step 1
1362    */
1363
1364   minimizationsteps = 0;
1365   for (;;)
1366     {
1367       /*
1368        * propagate
1369        */
1370       if (level == 1)
1371         {
1372           POOL_DEBUG(SAT_DEBUG_PROPAGATE, "propagating (propagate_index: %d;  size decisionq: %d)...\n", solv->propagate_index, solv->decisionq.count);
1373           if ((r = propagate(solv, level)) != 0)
1374             {
1375               if (analyze_unsolvable(solv, r, disablerules))
1376                 continue;
1377               queue_free(&dq);
1378               queue_free(&dqs);
1379               return;
1380             }
1381         }
1382
1383      if (level < systemlevel)
1384         {
1385           POOL_DEBUG(SAT_DEBUG_SOLVER, "resolving job rules\n");
1386           for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
1387             {
1388               Id l;
1389               if (r->d < 0)             /* ignore disabled rules */
1390                 continue;
1391               queue_empty(&dq);
1392               FOR_RULELITERALS(l, dp, r)
1393                 {
1394                   if (l < 0)
1395                     {
1396                       if (solv->decisionmap[-l] <= 0)
1397                         break;
1398                     }
1399                   else
1400                     {
1401                       if (solv->decisionmap[l] > 0)
1402                         break;
1403                       if (solv->decisionmap[l] == 0)
1404                         queue_push(&dq, l);
1405                     }
1406                 }
1407               if (l || !dq.count)
1408                 continue;
1409               /* prune to installed if not updating */
1410               if (!solv->updatesystem && solv->installed && dq.count > 1)
1411                 {
1412                   int j, k;
1413                   for (j = k = 0; j < dq.count; j++)
1414                     {
1415                       Solvable *s = pool->solvables + dq.elements[j];
1416                       if (s->repo == solv->installed)
1417                         dq.elements[k++] = dq.elements[j];
1418                     }
1419                   if (k)
1420                     dq.count = k;
1421                 }
1422               olevel = level;
1423               level = selectandinstall(solv, level, &dq, disablerules, i);
1424               if (level == 0)
1425                 {
1426                   queue_free(&dq);
1427                   queue_free(&dqs);
1428                   return;
1429                 }
1430               if (level <= olevel)
1431                 break;
1432             }
1433           systemlevel = level + 1;
1434           if (i < solv->jobrules_end)
1435             continue;
1436         }
1437
1438
1439       /*
1440        * installed packages
1441        */
1442
1443       if (level < systemlevel && solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
1444         {
1445           Repo *installed = solv->installed;
1446           int pass;
1447
1448           POOL_DEBUG(SAT_DEBUG_SOLVER, "resolving installed packages\n");
1449           /* we use two passes if we need to update packages
1450            * to create a better user experience */
1451           for (pass = solv->updatemap.size ? 0 : 1; pass < 2; pass++)
1452             {
1453               int passlevel = level;
1454               /* start with installedpos, the position that gave us problems last time */
1455               for (i = installedpos, n = installed->start; n < installed->end; i++, n++)
1456                 {
1457                   Rule *rr;
1458                   Id d;
1459
1460                   if (i == installed->end)
1461                     i = installed->start;
1462                   s = pool->solvables + i;
1463                   if (s->repo != installed)
1464                     continue;
1465
1466                   if (solv->decisionmap[i] > 0)
1467                     continue;
1468                   /* XXX: noupdate check is probably no longer needed, as all jobs should
1469                    * already be satisfied */
1470                   if (MAPTST(&solv->noupdate, i - installed->start))
1471                     continue;
1472                   if (!pass && solv->updatemap.size && !MAPTST(&solv->updatemap, i - installed->start))
1473                     continue;           /* updates first */
1474                   r = solv->rules + solv->updaterules + (i - installed->start);
1475                   rr = r;
1476                   if (!rr->p || rr->d < 0)      /* disabled -> look at feature rule */
1477                     rr -= solv->installed->end - solv->installed->start;
1478                   if (!rr->p)           /* identical to update rule? */
1479                     rr = r;
1480                   if (!rr->p)
1481                     continue;           /* orpaned package */
1482
1483                   queue_empty(&dq);
1484                   if (solv->decisionmap[i] < 0 || solv->updatesystem || (solv->updatemap.size && MAPTST(&solv->updatemap, i - installed->start)) || rr->p != i)
1485                     {
1486                       if (solv->noobsoletes.size && solv->multiversionupdaters
1487                              && (d = solv->multiversionupdaters[i - installed->start]) != 0)
1488                         {
1489                           /* special multiversion handling, make sure best version is chosen */
1490                           queue_push(&dq, i);
1491                           while ((p = pool->whatprovidesdata[d++]) != 0)
1492                             if (solv->decisionmap[p] >= 0)
1493                               queue_push(&dq, p);
1494                           policy_filter_unwanted(solv, &dq, POLICY_MODE_CHOOSE);
1495                           p = dq.elements[0];
1496                           if (p != i && solv->decisionmap[p] == 0)
1497                             {
1498                               rr = solv->rules + solv->featurerules + (i - solv->installed->start);
1499                               if (!rr->p)               /* update rule == feature rule? */
1500                                 rr = rr - solv->featurerules + solv->updaterules;
1501                               dq.count = 1;
1502                             }
1503                           else
1504                             dq.count = 0;
1505                         }
1506                       else
1507                         {
1508                           /* update to best package */
1509                           FOR_RULELITERALS(p, dp, rr)
1510                             {
1511                               if (solv->decisionmap[p] > 0)
1512                                 {
1513                                   dq.count = 0;         /* already fulfilled */
1514                                   break;
1515                                 }
1516                               if (!solv->decisionmap[p])
1517                                 queue_push(&dq, p);
1518                             }
1519                         }
1520                     }
1521                   /* install best version */
1522                   if (dq.count)
1523                     {
1524                       olevel = level;
1525                       level = selectandinstall(solv, level, &dq, disablerules, rr - solv->rules);
1526                       if (level == 0)
1527                         {
1528                           queue_free(&dq);
1529                           queue_free(&dqs);
1530                           return;
1531                         }
1532                       if (level <= olevel)
1533                         {
1534                           if (level < passlevel)
1535                             break;      /* trouble */
1536                           if (level < olevel)
1537                             n = installed->start;       /* redo all */
1538                           i--;
1539                           n--;
1540                           continue;
1541                         }
1542                     }
1543                   /* if still undecided keep package */
1544                   if (solv->decisionmap[i] == 0)
1545                     {
1546                       olevel = level;
1547                       POOL_DEBUG(SAT_DEBUG_POLICY, "keeping %s\n", solvid2str(pool, i));
1548                       level = setpropagatelearn(solv, level, i, disablerules, r - solv->rules);
1549                       if (level == 0)
1550                         {
1551                           queue_free(&dq);
1552                           queue_free(&dqs);
1553                           return;
1554                         }
1555                       if (level <= olevel)
1556                         {
1557                           if (level < passlevel)
1558                             break;      /* trouble */
1559                           if (level < olevel)
1560                             n = installed->start;       /* redo all */
1561                           i--;
1562                           n--;
1563                           continue; /* retry with learnt rule */
1564                         }
1565                     }
1566                 }
1567               if (n < installed->end)
1568                 {
1569                   installedpos = i;     /* retry problem solvable next time */
1570                   break;                /* ran into trouble */
1571                 }
1572               installedpos = installed->start;  /* reset installedpos */
1573             }
1574           systemlevel = level + 1;
1575           if (pass < 2)
1576             continue;           /* had trouble, retry */
1577         }
1578
1579       if (level < systemlevel)
1580         systemlevel = level;
1581
1582       /*
1583        * decide
1584        */
1585
1586       POOL_DEBUG(SAT_DEBUG_POLICY, "deciding unresolved rules\n");
1587       for (i = 1, n = 1; n < solv->nrules; i++, n++)
1588         {
1589           if (i == solv->nrules)
1590             i = 1;
1591           r = solv->rules + i;
1592           if (r->d < 0)         /* ignore disabled rules */
1593             continue;
1594           queue_empty(&dq);
1595           if (r->d == 0)
1596             {
1597               /* binary or unary rule */
1598               /* need two positive undecided literals */
1599               if (r->p < 0 || r->w2 <= 0)
1600                 continue;
1601               if (solv->decisionmap[r->p] || solv->decisionmap[r->w2])
1602                 continue;
1603               queue_push(&dq, r->p);
1604               queue_push(&dq, r->w2);
1605             }
1606           else
1607             {
1608               /* make sure that
1609                * all negative literals are installed
1610                * no positive literal is installed
1611                * i.e. the rule is not fulfilled and we
1612                * just need to decide on the positive literals
1613                */
1614               if (r->p < 0)
1615                 {
1616                   if (solv->decisionmap[-r->p] <= 0)
1617                     continue;
1618                 }
1619               else
1620                 {
1621                   if (solv->decisionmap[r->p] > 0)
1622                     continue;
1623                   if (solv->decisionmap[r->p] == 0)
1624                     queue_push(&dq, r->p);
1625                 }
1626               dp = pool->whatprovidesdata + r->d;
1627               while ((p = *dp++) != 0)
1628                 {
1629                   if (p < 0)
1630                     {
1631                       if (solv->decisionmap[-p] <= 0)
1632                         break;
1633                     }
1634                   else
1635                     {
1636                       if (solv->decisionmap[p] > 0)
1637                         break;
1638                       if (solv->decisionmap[p] == 0)
1639                         queue_push(&dq, p);
1640                     }
1641                 }
1642               if (p)
1643                 continue;
1644             }
1645           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
1646             {
1647               POOL_DEBUG(SAT_DEBUG_PROPAGATE, "unfulfilled ");
1648               solver_printruleclass(solv, SAT_DEBUG_PROPAGATE, r);
1649             }
1650           /* dq.count < 2 cannot happen as this means that
1651            * the rule is unit */
1652           assert(dq.count > 1);
1653
1654           olevel = level;
1655           level = selectandinstall(solv, level, &dq, disablerules, r - solv->rules);
1656           if (level == 0)
1657             {
1658               queue_free(&dq);
1659               queue_free(&dqs);
1660               return;
1661             }
1662           if (level < systemlevel || level == 1)
1663             break;              /* trouble */
1664           /* something changed, so look at all rules again */
1665           n = 0;
1666         }
1667
1668       if (n != solv->nrules)    /* ran into trouble, restart */
1669         continue;
1670
1671       if (doweak)
1672         {
1673           int qcount;
1674
1675           POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended packages\n");
1676           queue_empty(&dq);     /* recommended packages */
1677           queue_empty(&dqs);    /* supplemented packages */
1678           for (i = 1; i < pool->nsolvables; i++)
1679             {
1680               if (solv->decisionmap[i] < 0)
1681                 continue;
1682               if (solv->decisionmap[i] > 0)
1683                 {
1684                   /* installed, check for recommends */
1685                   Id *recp, rec, pp, p;
1686                   s = pool->solvables + i;
1687                   if (solv->ignorealreadyrecommended && s->repo == solv->installed)
1688                     continue;
1689                   /* XXX need to special case AND ? */
1690                   if (s->recommends)
1691                     {
1692                       recp = s->repo->idarraydata + s->recommends;
1693                       while ((rec = *recp++) != 0)
1694                         {
1695                           qcount = dq.count;
1696                           FOR_PROVIDES(p, pp, rec)
1697                             {
1698                               if (solv->decisionmap[p] > 0)
1699                                 {
1700                                   dq.count = qcount;
1701                                   break;
1702                                 }
1703                               else if (solv->decisionmap[p] == 0)
1704                                 {
1705                                   queue_pushunique(&dq, p);
1706                                 }
1707                             }
1708                         }
1709                     }
1710                 }
1711               else
1712                 {
1713                   s = pool->solvables + i;
1714                   if (!s->supplements)
1715                     continue;
1716                   if (!pool_installable(pool, s))
1717                     continue;
1718                   if (!solver_is_supplementing(solv, s))
1719                     continue;
1720                   queue_push(&dqs, i);
1721                 }
1722             }
1723
1724           /* filter out all packages obsoleted by installed packages */
1725           /* this is no longer needed if we have reverse obsoletes */
1726           if ((dqs.count || dq.count) && solv->installed)
1727             {
1728               Map obsmap;
1729               Id obs, *obsp, po, ppo;
1730
1731               map_init(&obsmap, pool->nsolvables);
1732               for (p = solv->installed->start; p < solv->installed->end; p++)
1733                 {
1734                   s = pool->solvables + p;
1735                   if (s->repo != solv->installed || !s->obsoletes)
1736                     continue;
1737                   if (solv->decisionmap[p] <= 0)
1738                     continue;
1739                   if (solv->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
1740                     continue;
1741                   obsp = s->repo->idarraydata + s->obsoletes;
1742                   /* foreach obsoletes */
1743                   while ((obs = *obsp++) != 0)
1744                     FOR_PROVIDES(po, ppo, obs)
1745                       MAPSET(&obsmap, po);
1746                 }
1747               for (i = j = 0; i < dqs.count; i++)
1748                 if (!MAPTST(&obsmap, dqs.elements[i]))
1749                   dqs.elements[j++] = dqs.elements[i];
1750               dqs.count = j;
1751               for (i = j = 0; i < dq.count; i++)
1752                 if (!MAPTST(&obsmap, dq.elements[i]))
1753                   dq.elements[j++] = dq.elements[i];
1754               dq.count = j;
1755               map_free(&obsmap);
1756             }
1757
1758           /* filter out all already supplemented packages if requested */
1759           if (solv->ignorealreadyrecommended && dqs.count)
1760             {
1761               /* turn off all new packages */
1762               for (i = 0; i < solv->decisionq.count; i++)
1763                 {
1764                   p = solv->decisionq.elements[i];
1765                   if (p < 0)
1766                     continue;
1767                   s = pool->solvables + p;
1768                   if (s->repo && s->repo != solv->installed)
1769                     solv->decisionmap[p] = -solv->decisionmap[p];
1770                 }
1771               /* filter out old supplements */
1772               for (i = j = 0; i < dqs.count; i++)
1773                 {
1774                   p = dqs.elements[i];
1775                   s = pool->solvables + p;
1776                   if (!s->supplements)
1777                     continue;
1778                   if (!solver_is_supplementing(solv, s))
1779                     dqs.elements[j++] = p;
1780                 }
1781               dqs.count = j;
1782               /* undo turning off */
1783               for (i = 0; i < solv->decisionq.count; i++)
1784                 {
1785                   p = solv->decisionq.elements[i];
1786                   if (p < 0)
1787                     continue;
1788                   s = pool->solvables + p;
1789                   if (s->repo && s->repo != solv->installed)
1790                     solv->decisionmap[p] = -solv->decisionmap[p];
1791                 }
1792             }
1793
1794           /* multiversion doesn't mix well with supplements.
1795            * filter supplemented packages where we already decided
1796            * to install a different version (see bnc#501088) */
1797           if (dqs.count && solv->noobsoletes.size)
1798             {
1799               for (i = j = 0; i < dqs.count; i++)
1800                 {
1801                   p = dqs.elements[i];
1802                   if (MAPTST(&solv->noobsoletes, p))
1803                     {
1804                       Id p2, pp2;
1805                       s = pool->solvables + p;
1806                       FOR_PROVIDES(p2, pp2, s->name)
1807                         if (solv->decisionmap[p2] > 0 && pool->solvables[p2].name == s->name)
1808                           break;
1809                       if (p2)
1810                         continue;       /* ignore this package */
1811                     }
1812                   dqs.elements[j++] = p;
1813                 }
1814               dqs.count = j;
1815             }
1816
1817           /* make dq contain both recommended and supplemented pkgs */
1818           if (dqs.count)
1819             {
1820               for (i = 0; i < dqs.count; i++)
1821                 queue_pushunique(&dq, dqs.elements[i]);
1822             }
1823
1824           if (dq.count)
1825             {
1826               Map dqmap;
1827               int decisioncount = solv->decisionq.count;
1828
1829               if (dq.count == 1)
1830                 {
1831                   /* simple case, just one package. no need to choose  */
1832                   p = dq.elements[0];
1833                   if (dqs.count)
1834                     POOL_DEBUG(SAT_DEBUG_POLICY, "installing supplemented %s\n", solvid2str(pool, p));
1835                   else
1836                     POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended %s\n", solvid2str(pool, p));
1837                   queue_push(&solv->recommendations, p);
1838                   level = setpropagatelearn(solv, level, p, 0, 0);
1839                   continue;     /* back to main loop */
1840                 }
1841
1842               /* filter packages, this gives us the best versions */
1843               policy_filter_unwanted(solv, &dq, POLICY_MODE_RECOMMEND);
1844
1845               /* create map of result */
1846               map_init(&dqmap, pool->nsolvables);
1847               for (i = 0; i < dq.count; i++)
1848                 MAPSET(&dqmap, dq.elements[i]);
1849
1850               /* install all supplemented packages */
1851               for (i = 0; i < dqs.count; i++)
1852                 {
1853                   p = dqs.elements[i];
1854                   if (solv->decisionmap[p] || !MAPTST(&dqmap, p))
1855                     continue;
1856                   POOL_DEBUG(SAT_DEBUG_POLICY, "installing supplemented %s\n", solvid2str(pool, p));
1857                   queue_push(&solv->recommendations, p);
1858                   olevel = level;
1859                   level = setpropagatelearn(solv, level, p, 0, 0);
1860                   if (level <= olevel)
1861                     break;
1862                 }
1863               if (i < dqs.count || solv->decisionq.count < decisioncount)
1864                 {
1865                   map_free(&dqmap);
1866                   continue;
1867                 }
1868
1869               /* install all recommended packages */
1870               /* more work as we want to created branches if multiple
1871                * choices are valid */
1872               for (i = 0; i < decisioncount; i++)
1873                 {
1874                   Id rec, *recp, pp;
1875                   p = solv->decisionq.elements[i];
1876                   if (p < 0)
1877                     continue;
1878                   s = pool->solvables + p;
1879                   if (!s->repo || (solv->ignorealreadyrecommended && s->repo == solv->installed))
1880                     continue;
1881                   if (!s->recommends)
1882                     continue;
1883                   recp = s->repo->idarraydata + s->recommends;
1884                   while ((rec = *recp++) != 0)
1885                     {
1886                       queue_empty(&dq);
1887                       FOR_PROVIDES(p, pp, rec)
1888                         {
1889                           if (solv->decisionmap[p] > 0)
1890                             {
1891                               dq.count = 0;
1892                               break;
1893                             }
1894                           else if (solv->decisionmap[p] == 0 && MAPTST(&dqmap, p))
1895                             queue_pushunique(&dq, p);
1896                         }
1897                       if (!dq.count)
1898                         continue;
1899                       if (dq.count > 1)
1900                         {
1901                           /* multiple candidates, open a branch */
1902                           for (i = 1; i < dq.count; i++)
1903                             queue_push(&solv->branches, dq.elements[i]);
1904                           queue_push(&solv->branches, -level);
1905                         }
1906                       p = dq.elements[0];
1907                       POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended %s\n", solvid2str(pool, p));
1908                       queue_push(&solv->recommendations, p);
1909                       olevel = level;
1910                       level = setpropagatelearn(solv, level, p, 0, 0);
1911                       if (level <= olevel || solv->decisionq.count < decisioncount)
1912                         break;  /* we had to revert some decisions */
1913                     }
1914                   if (rec)
1915                     break;      /* had a problem above, quit loop */
1916                 }
1917               map_free(&dqmap);
1918
1919               continue;         /* back to main loop */
1920             }
1921         }
1922
1923      if (solv->distupgrade && solv->installed)
1924         {
1925           int installedone = 0;
1926
1927           /* let's see if we can install some unsupported package */
1928           POOL_DEBUG(SAT_DEBUG_SOLVER, "deciding unsupported packages\n");
1929           for (i = 0; i < solv->orphaned.count; i++)
1930             {
1931               p = solv->orphaned.elements[i];
1932               if (solv->decisionmap[p])
1933                 continue;       /* already decided */
1934               olevel = level;
1935               if (solv->distupgrade_removeunsupported)
1936                 {
1937                   POOL_DEBUG(SAT_DEBUG_SOLVER, "removing unsupported %s\n", solvid2str(pool, p));
1938                   level = setpropagatelearn(solv, level, -p, 0, 0);
1939                 }
1940               else
1941                 {
1942                   POOL_DEBUG(SAT_DEBUG_SOLVER, "keeping unsupported %s\n", solvid2str(pool, p));
1943                   level = setpropagatelearn(solv, level, p, 0, 0);
1944                   installedone = 1;
1945                 }
1946               if (level < olevel)
1947                 break;
1948             }
1949           if (installedone || i < solv->orphaned.count)
1950             continue;
1951         }
1952
1953      if (solv->solution_callback)
1954         {
1955           solv->solution_callback(solv, solv->solution_callback_data);
1956           if (solv->branches.count)
1957             {
1958               int i = solv->branches.count - 1;
1959               int l = -solv->branches.elements[i];
1960               Id why;
1961
1962               for (; i > 0; i--)
1963                 if (solv->branches.elements[i - 1] < 0)
1964                   break;
1965               p = solv->branches.elements[i];
1966               POOL_DEBUG(SAT_DEBUG_SOLVER, "branching with %s\n", solvid2str(pool, p));
1967               queue_empty(&dq);
1968               for (j = i + 1; j < solv->branches.count; j++)
1969                 queue_push(&dq, solv->branches.elements[j]);
1970               solv->branches.count = i;
1971               level = l;
1972               revert(solv, level);
1973               if (dq.count > 1)
1974                 for (j = 0; j < dq.count; j++)
1975                   queue_push(&solv->branches, dq.elements[j]);
1976               olevel = level;
1977               why = -solv->decisionq_why.elements[solv->decisionq_why.count];
1978               assert(why >= 0);
1979               level = setpropagatelearn(solv, level, p, disablerules, why);
1980               if (level == 0)
1981                 {
1982                   queue_free(&dq);
1983                   queue_free(&dqs);
1984                   return;
1985                 }
1986               continue;
1987             }
1988           /* all branches done, we're finally finished */
1989           break;
1990         }
1991
1992       /* minimization step */
1993      if (solv->branches.count)
1994         {
1995           int l = 0, lasti = -1, lastl = -1;
1996           Id why;
1997
1998           p = 0;
1999           for (i = solv->branches.count - 1; i >= 0; i--)
2000             {
2001               p = solv->branches.elements[i];
2002               if (p < 0)
2003                 l = -p;
2004               else if (p > 0 && solv->decisionmap[p] > l + 1)
2005                 {
2006                   lasti = i;
2007                   lastl = l;
2008                 }
2009             }
2010           if (lasti >= 0)
2011             {
2012               /* kill old solvable so that we do not loop */
2013               p = solv->branches.elements[lasti];
2014               solv->branches.elements[lasti] = 0;
2015               POOL_DEBUG(SAT_DEBUG_SOLVER, "minimizing %d -> %d with %s\n", solv->decisionmap[p], lastl, solvid2str(pool, p));
2016               minimizationsteps++;
2017
2018               level = lastl;
2019               revert(solv, level);
2020               why = -solv->decisionq_why.elements[solv->decisionq_why.count];
2021               assert(why >= 0);
2022               olevel = level;
2023               level = setpropagatelearn(solv, level, p, disablerules, why);
2024               if (level == 0)
2025                 {
2026                   queue_free(&dq);
2027                   queue_free(&dqs);
2028                   return;
2029                 }
2030               continue;
2031             }
2032         }
2033       /* no minimization found, we're finally finished! */
2034       break;
2035     }
2036   POOL_DEBUG(SAT_DEBUG_STATS, "solver statistics: %d learned rules, %d unsolvable, %d minimization steps\n", solv->stats_learned, solv->stats_unsolvable, minimizationsteps);
2037
2038   POOL_DEBUG(SAT_DEBUG_STATS, "done solving.\n\n");
2039   queue_free(&dq);
2040   queue_free(&dqs);
2041 #if 0
2042   solver_printdecisionq(solv, SAT_DEBUG_RESULT);
2043 #endif
2044 }
2045
2046
2047 /*-------------------------------------------------------------------
2048  *
2049  * remove disabled conflicts
2050  *
2051  * purpose: update the decisionmap after some rules were disabled.
2052  * this is used to calculate the suggested/recommended package list.
2053  * Also returns a "removed" list to undo the discisionmap changes.
2054  */
2055
2056 static void
2057 removedisabledconflicts(Solver *solv, Queue *removed)
2058 {
2059   Pool *pool = solv->pool;
2060   int i, n;
2061   Id p, why, *dp;
2062   Id new;
2063   Rule *r;
2064   Id *decisionmap = solv->decisionmap;
2065
2066   POOL_DEBUG(SAT_DEBUG_SCHUBI, "removedisabledconflicts\n");
2067   queue_empty(removed);
2068   for (i = 0; i < solv->decisionq.count; i++)
2069     {
2070       p = solv->decisionq.elements[i];
2071       if (p > 0)
2072         continue;
2073       /* a conflict. we never do conflicts on free decisions, so there
2074        * must have been an unit rule */
2075       why = solv->decisionq_why.elements[i];
2076       assert(why > 0);
2077       r = solv->rules + why;
2078       if (r->d < 0 && decisionmap[-p])
2079         {
2080           /* rule is now disabled, remove from decisionmap */
2081           POOL_DEBUG(SAT_DEBUG_SCHUBI, "removing conflict for package %s[%d]\n", solvid2str(pool, -p), -p);
2082           queue_push(removed, -p);
2083           queue_push(removed, decisionmap[-p]);
2084           decisionmap[-p] = 0;
2085         }
2086     }
2087   if (!removed->count)
2088     return;
2089   /* we removed some confliced packages. some of them might still
2090    * be in conflict, so search for unit rules and re-conflict */
2091   new = 0;
2092   for (i = n = 1, r = solv->rules + i; n < solv->nrules; i++, r++, n++)
2093     {
2094       if (i == solv->nrules)
2095         {
2096           i = 1;
2097           r = solv->rules + i;
2098         }
2099       if (r->d < 0)
2100         continue;
2101       if (!r->w2)
2102         {
2103           if (r->p < 0 && !decisionmap[-r->p])
2104             new = r->p;
2105         }
2106       else if (!r->d)
2107         {
2108           /* binary rule */
2109           if (r->p < 0 && decisionmap[-r->p] == 0 && DECISIONMAP_FALSE(r->w2))
2110             new = r->p;
2111           else if (r->w2 < 0 && decisionmap[-r->w2] == 0 && DECISIONMAP_FALSE(r->p))
2112             new = r->w2;
2113         }
2114       else
2115         {
2116           if (r->p < 0 && decisionmap[-r->p] == 0)
2117             new = r->p;
2118           if (new || DECISIONMAP_FALSE(r->p))
2119             {
2120               dp = pool->whatprovidesdata + r->d;
2121               while ((p = *dp++) != 0)
2122                 {
2123                   if (new && p == new)
2124                     continue;
2125                   if (p < 0 && decisionmap[-p] == 0)
2126                     {
2127                       if (new)
2128                         {
2129                           new = 0;
2130                           break;
2131                         }
2132                       new = p;
2133                     }
2134                   else if (!DECISIONMAP_FALSE(p))
2135                     {
2136                       new = 0;
2137                       break;
2138                     }
2139                 }
2140             }
2141         }
2142       if (new)
2143         {
2144           POOL_DEBUG(SAT_DEBUG_SCHUBI, "re-conflicting package %s[%d]\n", solvid2str(pool, -new), -new);
2145           decisionmap[-new] = -1;
2146           new = 0;
2147           n = 0;        /* redo all rules */
2148         }
2149     }
2150 }
2151
2152 static inline void
2153 undo_removedisabledconflicts(Solver *solv, Queue *removed)
2154 {
2155   int i;
2156   for (i = 0; i < removed->count; i += 2)
2157     solv->decisionmap[removed->elements[i]] = removed->elements[i + 1];
2158 }
2159
2160
2161 /*-------------------------------------------------------------------
2162  *
2163  * weaken solvable dependencies
2164  */
2165
2166 static void
2167 weaken_solvable_deps(Solver *solv, Id p)
2168 {
2169   int i;
2170   Rule *r;
2171
2172   for (i = 1, r = solv->rules + i; i < solv->rpmrules_end; i++, r++)
2173     {
2174       if (r->p != -p)
2175         continue;
2176       if ((r->d == 0 || r->d == -1) && r->w2 < 0)
2177         continue;       /* conflict */
2178       queue_push(&solv->weakruleq, i);
2179     }
2180 }
2181
2182
2183 /********************************************************************/
2184 /* main() */
2185
2186
2187 static void
2188 findrecommendedsuggested(Solver *solv)
2189 {
2190   Pool *pool = solv->pool;
2191   Queue redoq, disabledq;
2192   int goterase, i;
2193   Solvable *s;
2194   Rule *r;
2195   Map obsmap;
2196
2197   map_init(&obsmap, pool->nsolvables);
2198   if (solv->installed)
2199     {
2200       Id obs, *obsp, p, po, ppo;
2201       for (p = solv->installed->start; p < solv->installed->end; p++)
2202         {
2203           s = pool->solvables + p;
2204           if (s->repo != solv->installed || !s->obsoletes)
2205             continue;
2206           if (solv->decisionmap[p] <= 0)
2207             continue;
2208           if (solv->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
2209             continue;
2210           obsp = s->repo->idarraydata + s->obsoletes;
2211           /* foreach obsoletes */
2212           while ((obs = *obsp++) != 0)
2213             FOR_PROVIDES(po, ppo, obs)
2214               MAPSET(&obsmap, po);
2215         }
2216     }
2217
2218   queue_init(&redoq);
2219   queue_init(&disabledq);
2220   goterase = 0;
2221   /* disable all erase jobs (including weak "keep uninstalled" rules) */
2222   for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
2223     {
2224       if (r->d < 0)     /* disabled ? */
2225         continue;
2226       if (r->p >= 0)    /* install job? */
2227         continue;
2228       queue_push(&disabledq, i);
2229       solver_disablerule(solv, r);
2230       goterase++;
2231     }
2232
2233   if (goterase)
2234     {
2235       enabledisablelearntrules(solv);
2236       removedisabledconflicts(solv, &redoq);
2237     }
2238
2239   /*
2240    * find recommended packages
2241    */
2242
2243   /* if redoq.count == 0 we already found all recommended in the
2244    * solver run */
2245   if (redoq.count || solv->dontinstallrecommended || !solv->dontshowinstalledrecommended || solv->ignorealreadyrecommended)
2246     {
2247       Id rec, *recp, p, pp;
2248
2249       /* create map of all recommened packages */
2250       solv->recommends_index = -1;
2251       MAPZERO(&solv->recommendsmap);
2252       for (i = 0; i < solv->decisionq.count; i++)
2253         {
2254           p = solv->decisionq.elements[i];
2255           if (p < 0)
2256             continue;
2257           s = pool->solvables + p;
2258           if (s->recommends)
2259             {
2260               recp = s->repo->idarraydata + s->recommends;
2261               while ((rec = *recp++) != 0)
2262                 {
2263                   FOR_PROVIDES(p, pp, rec)
2264                     if (solv->decisionmap[p] > 0)
2265                       break;
2266                   if (p)
2267                     {
2268                       if (!solv->dontshowinstalledrecommended)
2269                         {
2270                           FOR_PROVIDES(p, pp, rec)
2271                             if (solv->decisionmap[p] > 0)
2272                               MAPSET(&solv->recommendsmap, p);
2273                         }
2274                       continue; /* p != 0: already fulfilled */
2275                     }
2276                   FOR_PROVIDES(p, pp, rec)
2277                     MAPSET(&solv->recommendsmap, p);
2278                 }
2279             }
2280         }
2281       for (i = 1; i < pool->nsolvables; i++)
2282         {
2283           if (solv->decisionmap[i] < 0)
2284             continue;
2285           if (solv->decisionmap[i] > 0 && solv->dontshowinstalledrecommended)
2286             continue;
2287           if (MAPTST(&obsmap, i))
2288             continue;
2289           s = pool->solvables + i;
2290           if (!MAPTST(&solv->recommendsmap, i))
2291             {
2292               if (!s->supplements)
2293                 continue;
2294               if (!pool_installable(pool, s))
2295                 continue;
2296               if (!solver_is_supplementing(solv, s))
2297                 continue;
2298             }
2299           if (solv->dontinstallrecommended)
2300             queue_push(&solv->recommendations, i);
2301           else
2302             queue_pushunique(&solv->recommendations, i);
2303         }
2304       /* we use MODE_SUGGEST here so that repo prio is ignored */
2305       policy_filter_unwanted(solv, &solv->recommendations, POLICY_MODE_SUGGEST);
2306     }
2307
2308   /*
2309    * find suggested packages
2310    */
2311
2312   if (1)
2313     {
2314       Id sug, *sugp, p, pp;
2315
2316       /* create map of all suggests that are still open */
2317       solv->recommends_index = -1;
2318       MAPZERO(&solv->suggestsmap);
2319       for (i = 0; i < solv->decisionq.count; i++)
2320         {
2321           p = solv->decisionq.elements[i];
2322           if (p < 0)
2323             continue;
2324           s = pool->solvables + p;
2325           if (s->suggests)
2326             {
2327               sugp = s->repo->idarraydata + s->suggests;
2328               while ((sug = *sugp++) != 0)
2329                 {
2330                   FOR_PROVIDES(p, pp, sug)
2331                     if (solv->decisionmap[p] > 0)
2332                       break;
2333                   if (p)
2334                     {
2335                       if (!solv->dontshowinstalledrecommended)
2336                         {
2337                           FOR_PROVIDES(p, pp, sug)
2338                             if (solv->decisionmap[p] > 0)
2339                               MAPSET(&solv->suggestsmap, p);
2340                         }
2341                       continue; /* already fulfilled */
2342                     }
2343                   FOR_PROVIDES(p, pp, sug)
2344                     MAPSET(&solv->suggestsmap, p);
2345                 }
2346             }
2347         }
2348       for (i = 1; i < pool->nsolvables; i++)
2349         {
2350           if (solv->decisionmap[i] < 0)
2351             continue;
2352           if (solv->decisionmap[i] > 0 && solv->dontshowinstalledrecommended)
2353             continue;
2354           if (MAPTST(&obsmap, i))
2355             continue;
2356           s = pool->solvables + i;
2357           if (!MAPTST(&solv->suggestsmap, i))
2358             {
2359               if (!s->enhances)
2360                 continue;
2361               if (!pool_installable(pool, s))
2362                 continue;
2363               if (!solver_is_enhancing(solv, s))
2364                 continue;
2365             }
2366           queue_push(&solv->suggestions, i);
2367         }
2368       policy_filter_unwanted(solv, &solv->suggestions, POLICY_MODE_SUGGEST);
2369     }
2370
2371   /* undo removedisabledconflicts */
2372   if (redoq.count)
2373     undo_removedisabledconflicts(solv, &redoq);
2374   queue_free(&redoq);
2375
2376   /* undo job rule disabling */
2377   for (i = 0; i < disabledq.count; i++)
2378     solver_enablerule(solv, solv->rules + disabledq.elements[i]);
2379   queue_free(&disabledq);
2380   map_free(&obsmap);
2381 }
2382
2383 void
2384 solver_calculate_noobsmap(Pool *pool, Queue *job, Map *noobsmap)
2385 {
2386   int i;
2387   Id how, what, select;
2388   Id p, pp;
2389   for (i = 0; i < job->count; i += 2)
2390     {
2391       how = job->elements[i];
2392       if ((how & SOLVER_JOBMASK) != SOLVER_NOOBSOLETES)
2393         continue;
2394       what = job->elements[i + 1];
2395       select = how & SOLVER_SELECTMASK;
2396       if (!noobsmap->size)
2397         map_grow(noobsmap, pool->nsolvables);
2398       FOR_JOB_SELECT(p, pp, select, what)
2399         MAPSET(noobsmap, p);
2400     }
2401 }
2402
2403 /*
2404  *
2405  * solve job queue
2406  *
2407  */
2408
2409 void
2410 solver_solve(Solver *solv, Queue *job)
2411 {
2412   Pool *pool = solv->pool;
2413   Repo *installed = solv->installed;
2414   int i;
2415   int oldnrules;
2416   Map addedmap;                /* '1' == have rpm-rules for solvable */
2417   Map installcandidatemap;
2418   Id how, what, select, name, weak, p, pp, d;
2419   Queue q;
2420   Solvable *s;
2421   Rule *r;
2422   int now, solve_start;
2423   int hasdupjob = 0;
2424
2425   solve_start = sat_timems(0);
2426
2427   /* log solver options */
2428   POOL_DEBUG(SAT_DEBUG_STATS, "solver started\n");
2429   POOL_DEBUG(SAT_DEBUG_STATS, "fixsystem=%d updatesystem=%d dosplitprovides=%d, noupdateprovide=%d noinfarchcheck=%d\n", solv->fixsystem, solv->updatesystem, solv->dosplitprovides, solv->noupdateprovide, solv->noinfarchcheck);
2430   POOL_DEBUG(SAT_DEBUG_STATS, "distupgrade=%d distupgrade_removeunsupported=%d\n", solv->distupgrade, solv->distupgrade_removeunsupported);
2431   POOL_DEBUG(SAT_DEBUG_STATS, "allowuninstall=%d, allowdowngrade=%d, allowarchchange=%d, allowvendorchange=%d\n", solv->allowuninstall, solv->allowdowngrade, solv->allowarchchange, solv->allowvendorchange);
2432   POOL_DEBUG(SAT_DEBUG_STATS, "promoteepoch=%d, novirtualconflicts=%d, allowselfconflicts=%d\n", pool->promoteepoch, pool->novirtualconflicts, pool->allowselfconflicts);
2433   POOL_DEBUG(SAT_DEBUG_STATS, "obsoleteusesprovides=%d, implicitobsoleteusesprovides=%d, obsoleteusescolors=%d\n", pool->obsoleteusesprovides, pool->implicitobsoleteusesprovides, pool->obsoleteusescolors);
2434   POOL_DEBUG(SAT_DEBUG_STATS, "dontinstallrecommended=%d, ignorealreadyrecommended=%d, dontshowinstalledrecommended=%d\n", solv->dontinstallrecommended, solv->ignorealreadyrecommended, solv->dontshowinstalledrecommended);
2435
2436   /* create whatprovides if not already there */
2437   if (!pool->whatprovides)
2438     pool_createwhatprovides(pool);
2439
2440   /* create obsolete index */
2441   policy_create_obsolete_index(solv);
2442
2443   /* remember job */
2444   queue_free(&solv->job);
2445   queue_init_clone(&solv->job, job);
2446
2447   /*
2448    * create basic rule set of all involved packages
2449    * use addedmap bitmap to make sure we don't create rules twice
2450    */
2451
2452   /* create noobsolete map if needed */
2453   solver_calculate_noobsmap(pool, job, &solv->noobsoletes);
2454
2455   map_init(&addedmap, pool->nsolvables);
2456   MAPSET(&addedmap, SYSTEMSOLVABLE);
2457
2458   map_init(&installcandidatemap, pool->nsolvables);
2459   queue_init(&q);
2460
2461   now = sat_timems(0);
2462   /*
2463    * create rules for all package that could be involved with the solving
2464    * so called: rpm rules
2465    *
2466    */
2467   if (installed)
2468     {
2469       /* check for verify jobs */
2470       for (i = 0; i < job->count; i += 2)
2471         {
2472           how = job->elements[i];
2473           what = job->elements[i + 1];
2474           select = how & SOLVER_SELECTMASK;
2475           switch (how & SOLVER_JOBMASK)
2476             {
2477             case SOLVER_VERIFY:
2478               FOR_JOB_SELECT(p, pp, select, what)
2479                 {
2480                   s = pool->solvables + p;
2481                   if (!solv->installed || s->repo != solv->installed)
2482                     continue;
2483                   if (!solv->fixmap.size)
2484                     map_grow(&solv->fixmap, solv->installed->end - solv->installed->start);
2485                   MAPSET(&solv->fixmap, p - solv->installed->start);
2486                 }
2487               break;
2488             default:
2489               break;
2490             }
2491         }
2492
2493       oldnrules = solv->nrules;
2494       POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for installed solvables ***\n");
2495       FOR_REPO_SOLVABLES(installed, p, s)
2496         solver_addrpmrulesforsolvable(solv, s, &addedmap);
2497       POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules for installed solvables\n", solv->nrules - oldnrules);
2498       POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for updaters of installed solvables ***\n");
2499       oldnrules = solv->nrules;
2500       FOR_REPO_SOLVABLES(installed, p, s)
2501         solver_addrpmrulesforupdaters(solv, s, &addedmap, 1);
2502       POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules for updaters of installed solvables\n", solv->nrules - oldnrules);
2503     }
2504
2505   /*
2506    * create rules for all packages involved in the job
2507    * (to be installed or removed)
2508    */
2509
2510   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for packages involved with a job ***\n");
2511   oldnrules = solv->nrules;
2512   for (i = 0; i < job->count; i += 2)
2513     {
2514       how = job->elements[i];
2515       what = job->elements[i + 1];
2516       select = how & SOLVER_SELECTMASK;
2517
2518       switch (how & SOLVER_JOBMASK)
2519         {
2520         case SOLVER_INSTALL:
2521           FOR_JOB_SELECT(p, pp, select, what)
2522             {
2523               MAPSET(&installcandidatemap, p);
2524               solver_addrpmrulesforsolvable(solv, pool->solvables + p, &addedmap);
2525             }
2526           break;
2527         case SOLVER_DISTUPGRADE:
2528           if (!solv->distupgrade)
2529             hasdupjob = 1;
2530           break;
2531         default:
2532           break;
2533         }
2534     }
2535   POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules for packages involved in a job\n", solv->nrules - oldnrules);
2536
2537
2538   /*
2539    * add rules for suggests, enhances
2540    */
2541   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for suggested/enhanced packages ***\n");
2542   oldnrules = solv->nrules;
2543   solver_addrpmrulesforweak(solv, &addedmap);
2544   POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules because of weak dependencies\n", solv->nrules - oldnrules);
2545
2546   /*
2547    * first pass done, we now have all the rpm rules we need.
2548    * unify existing rules before going over all job rules and
2549    * policy rules.
2550    * at this point the system is always solvable,
2551    * as an empty system (remove all packages) is a valid solution
2552    */
2553
2554   IF_POOLDEBUG (SAT_DEBUG_STATS)
2555     {
2556       int possible = 0, installable = 0;
2557       for (i = 1; i < pool->nsolvables; i++)
2558         {
2559           if (pool_installable(pool, pool->solvables + i))
2560             installable++;
2561           if (MAPTST(&addedmap, i))
2562             possible++;
2563         }
2564       POOL_DEBUG(SAT_DEBUG_STATS, "%d of %d installable solvables considered for solving\n", possible, installable);
2565     }
2566
2567   solver_unifyrules(solv);                          /* remove duplicate rpm rules */
2568   solv->rpmrules_end = solv->nrules;              /* mark end of rpm rules */
2569
2570   POOL_DEBUG(SAT_DEBUG_STATS, "rpm rule memory usage: %d K\n", solv->nrules * (int)sizeof(Rule) / 1024);
2571   POOL_DEBUG(SAT_DEBUG_STATS, "rpm rule creation took %d ms\n", sat_timems(now));
2572
2573   /* create dup maps if needed. We need the maps early to create our
2574    * update rules */
2575   if (hasdupjob)
2576     solver_createdupmaps(solv);
2577
2578   /*
2579    * create feature rules
2580    *
2581    * foreach installed:
2582    *   create assertion (keep installed, if no update available)
2583    *   or
2584    *   create update rule (A|update1(A)|update2(A)|...)
2585    *
2586    * those are used later on to keep a version of the installed packages in
2587    * best effort mode
2588    */
2589
2590   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** Add feature rules ***\n");
2591   solv->featurerules = solv->nrules;              /* mark start of feature rules */
2592   if (installed)
2593     {
2594       /* foreach possibly installed solvable */
2595       for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
2596         {
2597           if (s->repo != installed)
2598             {
2599               solver_addrule(solv, 0, 0);       /* create dummy rule */
2600               continue;
2601             }
2602           solver_addupdaterule(solv, s, 1);    /* allow s to be updated */
2603         }
2604       /* make sure we accounted for all rules */
2605       assert(solv->nrules - solv->featurerules == installed->end - installed->start);
2606     }
2607   solv->featurerules_end = solv->nrules;
2608
2609     /*
2610      * Add update rules for installed solvables
2611      *
2612      * almost identical to feature rules
2613      * except that downgrades/archchanges/vendorchanges are not allowed
2614      */
2615
2616   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** Add update rules ***\n");
2617   solv->updaterules = solv->nrules;
2618
2619   if (installed)
2620     { /* foreach installed solvables */
2621       /* we create all update rules, but disable some later on depending on the job */
2622       for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
2623         {
2624           Rule *sr;
2625
2626           if (s->repo != installed)
2627             {
2628               solver_addrule(solv, 0, 0);       /* create dummy rule */
2629               continue;
2630             }
2631           solver_addupdaterule(solv, s, 0);     /* allowall = 0: downgrades not allowed */
2632           /*
2633            * check for and remove duplicate
2634            */
2635           r = solv->rules + solv->nrules - 1;           /* r: update rule */
2636           sr = r - (installed->end - installed->start); /* sr: feature rule */
2637           /* it's orphaned if there is no feature rule or the feature rule
2638            * consists just of the installed package */
2639           if (!sr->p || (sr->p == i && !sr->d && !sr->w2))
2640             queue_push(&solv->orphaned, i);
2641           if (!r->p)
2642             {
2643               assert(solv->distupgrade && !sr->p);
2644               continue;
2645             }
2646           if (!solver_samerule(solv, r, sr))
2647             {
2648               /* identical rule, kill unneeded one */
2649               if (solv->allowuninstall)
2650                 {
2651                   /* keep feature rule, make it weak */
2652                   memset(r, 0, sizeof(*r));
2653                   queue_push(&solv->weakruleq, sr - solv->rules);
2654                 }
2655               else
2656                 {
2657                   /* keep update rule */
2658                   memset(sr, 0, sizeof(*sr));
2659                 }
2660             }
2661           else if (solv->allowuninstall)
2662             {
2663               /* make both feature and update rule weak */
2664               queue_push(&solv->weakruleq, r - solv->rules);
2665               queue_push(&solv->weakruleq, sr - solv->rules);
2666             }
2667           else
2668             solver_disablerule(solv, sr);
2669         }
2670       /* consistency check: we added a rule for _every_ installed solvable */
2671       assert(solv->nrules - solv->updaterules == installed->end - installed->start);
2672     }
2673   solv->updaterules_end = solv->nrules;
2674
2675
2676   /*
2677    * now add all job rules
2678    */
2679
2680   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** Add JOB rules ***\n");
2681
2682   solv->jobrules = solv->nrules;
2683   for (i = 0; i < job->count; i += 2)
2684     {
2685       oldnrules = solv->nrules;
2686
2687       how = job->elements[i];
2688       what = job->elements[i + 1];
2689       weak = how & SOLVER_WEAK;
2690       select = how & SOLVER_SELECTMASK;
2691       switch (how & SOLVER_JOBMASK)
2692         {
2693         case SOLVER_INSTALL:
2694           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sinstall %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2695           if (select == SOLVER_SOLVABLE)
2696             {
2697               p = what;
2698               d = 0;
2699             }
2700           else
2701             {
2702               queue_empty(&q);
2703               FOR_JOB_SELECT(p, pp, select, what)
2704                 queue_push(&q, p);
2705               if (!q.count)
2706                 {
2707                   /* no candidate found, make this an impossible rule */
2708                   queue_push(&q, -SYSTEMSOLVABLE);
2709                 }
2710               p = queue_shift(&q);      /* get first candidate */
2711               d = !q.count ? 0 : pool_queuetowhatprovides(pool, &q);    /* internalize */
2712             }
2713           solver_addrule(solv, p, d);           /* add install rule */
2714           queue_push(&solv->ruletojob, i);
2715           if (weak)
2716             queue_push(&solv->weakruleq, solv->nrules - 1);
2717           break;
2718         case SOLVER_ERASE:
2719           POOL_DEBUG(SAT_DEBUG_JOB, "job: %serase %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2720           if (select == SOLVER_SOLVABLE && solv->installed && pool->solvables[what].repo == solv->installed)
2721             {
2722               /* special case for "erase a specific solvable": we also
2723                * erase all other solvables with that name, so that they
2724                * don't get picked up as replacement */
2725               name = pool->solvables[what].name;
2726               FOR_PROVIDES(p, pp, name)
2727                 {
2728                   if (p == what)
2729                     continue;
2730                   s = pool->solvables + p;
2731                   if (s->name != name)
2732                     continue;
2733                   /* keep other versions installed */
2734                   if (s->repo == solv->installed)
2735                     continue;
2736                   /* keep installcandidates of other jobs */
2737                   if (MAPTST(&installcandidatemap, p))
2738                     continue;
2739                   solver_addrule(solv, -p, 0);                  /* remove by Id */
2740                   queue_push(&solv->ruletojob, i);
2741                   if (weak)
2742                     queue_push(&solv->weakruleq, solv->nrules - 1);
2743                 }
2744             }
2745           FOR_JOB_SELECT(p, pp, select, what)
2746             {
2747               solver_addrule(solv, -p, 0);
2748               queue_push(&solv->ruletojob, i);
2749               if (weak)
2750                 queue_push(&solv->weakruleq, solv->nrules - 1);
2751             }
2752           break;
2753
2754         case SOLVER_UPDATE:
2755           POOL_DEBUG(SAT_DEBUG_JOB, "job: %supdate %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2756           FOR_JOB_SELECT(p, pp, select, what)
2757             {
2758               s = pool->solvables + p;
2759               if (!solv->installed || s->repo != solv->installed)
2760                 continue;
2761               if (!solv->updatemap.size)
2762                 map_grow(&solv->updatemap, solv->installed->end - solv->installed->start);
2763               MAPSET(&solv->updatemap, p - solv->installed->start);
2764             }
2765           break;
2766         case SOLVER_VERIFY:
2767           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sverify %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2768           break;
2769         case SOLVER_WEAKENDEPS:
2770           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sweaken deps %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2771           if (select != SOLVER_SOLVABLE)
2772             break;
2773           s = pool->solvables + what;
2774           weaken_solvable_deps(solv, what);
2775           break;
2776         case SOLVER_NOOBSOLETES:
2777           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sno obsolete %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2778           break;
2779         case SOLVER_LOCK:
2780           POOL_DEBUG(SAT_DEBUG_JOB, "job: %slock %s\n", weak ? "weak " : "", solver_select2str(solv, select, what));
2781           FOR_JOB_SELECT(p, pp, select, what)
2782             {
2783               s = pool->solvables + p;
2784               if (installed && s->repo == installed)
2785                 solver_addrule(solv, p, 0);
2786               else
2787                 solver_addrule(solv, -p, 0);
2788               queue_push(&solv->ruletojob, i);
2789               if (weak)
2790                 queue_push(&solv->weakruleq, solv->nrules - 1);
2791             }
2792           break;
2793         case SOLVER_DISTUPGRADE:
2794           POOL_DEBUG(SAT_DEBUG_JOB, "job: distupgrade repo #%d\n", what);
2795           break;
2796         default:
2797           POOL_DEBUG(SAT_DEBUG_JOB, "job: unknown job\n");
2798           break;
2799         }
2800
2801         /*
2802          * debug
2803          */
2804
2805       IF_POOLDEBUG (SAT_DEBUG_JOB)
2806         {
2807           int j;
2808           if (solv->nrules == oldnrules)
2809             POOL_DEBUG(SAT_DEBUG_JOB, " - no rule created\n");
2810           for (j = oldnrules; j < solv->nrules; j++)
2811             {
2812               POOL_DEBUG(SAT_DEBUG_JOB, " - job ");
2813               solver_printrule(solv, SAT_DEBUG_JOB, solv->rules + j);
2814             }
2815         }
2816     }
2817   assert(solv->ruletojob.count == solv->nrules - solv->jobrules);
2818   solv->jobrules_end = solv->nrules;
2819
2820   /* now create infarch and dup rules */
2821   if (!solv->noinfarchcheck)
2822     {
2823       solver_addinfarchrules(solv, &addedmap);
2824       if (pool->obsoleteusescolors)
2825         {
2826           /* currently doesn't work well with infarch rules, so make
2827            * them weak */
2828           for (i = solv->infarchrules; i < solv->infarchrules_end; i++)
2829             queue_push(&solv->weakruleq, i);
2830         }
2831     }
2832   else
2833     solv->infarchrules = solv->infarchrules_end = solv->nrules;
2834
2835   if (hasdupjob)
2836     {
2837       solver_addduprules(solv, &addedmap);
2838       solver_freedupmaps(solv); /* no longer needed */
2839     }
2840   else
2841     solv->duprules = solv->duprules_end = solv->nrules;
2842
2843   if (1)
2844     {
2845       extern void addchoicerules(Solver *solv);
2846       addchoicerules(solv);
2847     }
2848   else
2849     solv->choicerules = solv->choicerules_end = solv->nrules;
2850
2851   /* all rules created
2852    * --------------------------------------------------------------
2853    * prepare for solving
2854    */
2855
2856   /* free unneeded memory */
2857   map_free(&addedmap);
2858   map_free(&installcandidatemap);
2859   queue_free(&q);
2860
2861   POOL_DEBUG(SAT_DEBUG_STATS, "%d rpm rules, %d job rules, %d infarch rules, %d dup rules, %d choice rules\n", solv->rpmrules_end - 1, solv->jobrules_end - solv->jobrules, solv->infarchrules_end - solv->infarchrules, solv->duprules_end - solv->duprules, solv->choicerules_end - solv->choicerules);
2862
2863   /* create weak map */
2864   map_init(&solv->weakrulemap, solv->nrules);
2865   for (i = 0; i < solv->weakruleq.count; i++)
2866     {
2867       p = solv->weakruleq.elements[i];
2868       MAPSET(&solv->weakrulemap, p);
2869     }
2870
2871   /* all new rules are learnt after this point */
2872   solv->learntrules = solv->nrules;
2873
2874   /* create watches chains */
2875   makewatches(solv);
2876
2877   /* create assertion index. it is only used to speed up
2878    * makeruledecsions() a bit */
2879   for (i = 1, r = solv->rules + i; i < solv->nrules; i++, r++)
2880     if (r->p && !r->w2 && (r->d == 0 || r->d == -1))
2881       queue_push(&solv->ruleassertions, i);
2882
2883   /* disable update rules that conflict with our job */
2884   solver_disablepolicyrules(solv);
2885
2886   /* make decisions based on job/update assertions */
2887   makeruledecisions(solv);
2888   POOL_DEBUG(SAT_DEBUG_SOLVER, "problems so far: %d\n", solv->problems.count);
2889
2890   /*
2891    * ********************************************
2892    * solve!
2893    * ********************************************
2894    */
2895
2896   now = sat_timems(0);
2897   solver_run_sat(solv, 1, solv->dontinstallrecommended ? 0 : 1);
2898   POOL_DEBUG(SAT_DEBUG_STATS, "solver took %d ms\n", sat_timems(now));
2899
2900   /*
2901    * calculate recommended/suggested packages
2902    */
2903   findrecommendedsuggested(solv);
2904
2905   /*
2906    * prepare solution queue if there were problems
2907    */
2908   solver_prepare_solutions(solv);
2909
2910   /*
2911    * finally prepare transaction info
2912    */
2913   transaction_calculate(&solv->trans, &solv->decisionq, &solv->noobsoletes);
2914
2915   POOL_DEBUG(SAT_DEBUG_STATS, "final solver statistics: %d problems, %d learned rules, %d unsolvable\n", solv->problems.count / 2, solv->stats_learned, solv->stats_unsolvable);
2916   POOL_DEBUG(SAT_DEBUG_STATS, "solver_solve took %d ms\n", sat_timems(solve_start));
2917 }
2918
2919 /***********************************************************************/
2920 /* disk usage computations */
2921
2922 /*-------------------------------------------------------------------
2923  *
2924  * calculate DU changes
2925  */
2926
2927 void
2928 solver_calc_duchanges(Solver *solv, DUChanges *mps, int nmps)
2929 {
2930   Map installedmap;
2931
2932   solver_create_state_maps(solv, &installedmap, 0);
2933   pool_calc_duchanges(solv->pool, &installedmap, mps, nmps);
2934   map_free(&installedmap);
2935 }
2936
2937
2938 /*-------------------------------------------------------------------
2939  *
2940  * calculate changes in install size
2941  */
2942
2943 int
2944 solver_calc_installsizechange(Solver *solv)
2945 {
2946   Map installedmap;
2947   int change;
2948
2949   solver_create_state_maps(solv, &installedmap, 0);
2950   change = pool_calc_installsizechange(solv->pool, &installedmap);
2951   map_free(&installedmap);
2952   return change;
2953 }
2954
2955 void
2956 solver_trivial_installable(Solver *solv, Queue *pkgs, Queue *res)
2957 {
2958   Map installedmap;
2959   solver_create_state_maps(solv, &installedmap, 0);
2960   pool_trivial_installable_noobsoletesmap(solv->pool, &installedmap, pkgs, res, solv->noobsoletes.size ? &solv->noobsoletes : 0);
2961   map_free(&installedmap);
2962 }
2963
2964
2965 #if 0
2966 #define FIND_INVOLVED_DEBUG 0
2967 void
2968 solver_find_involved(Solver *solv, Queue *installedq, Solvable *ts, Queue *q)
2969 {
2970   Pool *pool = solv->pool;
2971   Map im;
2972   Map installedm;
2973   Solvable *s;
2974   Queue iq;
2975   Queue installedq_internal;
2976   Id tp, ip, p, pp, req, *reqp, sup, *supp;
2977   int i, count;
2978
2979   tp = ts - pool->solvables;
2980   queue_init(&iq);
2981   queue_init(&installedq_internal);
2982   map_init(&im, pool->nsolvables);
2983   map_init(&installedm, pool->nsolvables);
2984
2985   if (!installedq)
2986     {
2987       installedq = &installedq_internal;
2988       if (solv->installed)
2989         {
2990           for (ip = solv->installed->start; ip < solv->installed->end; ip++)
2991             {
2992               s = pool->solvables + ip;
2993               if (s->repo != solv->installed)
2994                 continue;
2995               queue_push(installedq, ip);
2996             }
2997         }
2998     }
2999   for (i = 0; i < installedq->count; i++)
3000     {
3001       ip = installedq->elements[i];
3002       MAPSET(&installedm, ip);
3003       MAPSET(&im, ip);
3004     }
3005
3006   queue_push(&iq, ts - pool->solvables);
3007   while (iq.count)
3008     {
3009       ip = queue_shift(&iq);
3010       if (!MAPTST(&im, ip))
3011         continue;
3012       if (!MAPTST(&installedm, ip))
3013         continue;
3014       MAPCLR(&im, ip);
3015       s = pool->solvables + ip;
3016 #if FIND_INVOLVED_DEBUG
3017       printf("hello %s\n", solvable2str(pool, s));
3018 #endif
3019       if (s->requires)
3020         {
3021           reqp = s->repo->idarraydata + s->requires;
3022           while ((req = *reqp++) != 0)
3023             {
3024               if (req == SOLVABLE_PREREQMARKER)
3025                 continue;
3026               /* count number of installed packages that match */
3027               count = 0;
3028               FOR_PROVIDES(p, pp, req)
3029                 if (MAPTST(&installedm, p))
3030                   count++;
3031               if (count > 1)
3032                 continue;
3033               FOR_PROVIDES(p, pp, req)
3034                 {
3035                   if (MAPTST(&im, p))
3036                     {
3037 #if FIND_INVOLVED_DEBUG
3038                       printf("%s requires %s\n", solvid2str(pool, ip), solvid2str(pool, p));
3039 #endif
3040                       queue_push(&iq, p);
3041                     }
3042                 }
3043             }
3044         }
3045       if (s->recommends)
3046         {
3047           reqp = s->repo->idarraydata + s->recommends;
3048           while ((req = *reqp++) != 0)
3049             {
3050               count = 0;
3051               FOR_PROVIDES(p, pp, req)
3052                 if (MAPTST(&installedm, p))
3053                   count++;
3054               if (count > 1)
3055                 continue;
3056               FOR_PROVIDES(p, pp, req)
3057                 {
3058                   if (MAPTST(&im, p))
3059                     {
3060 #if FIND_INVOLVED_DEBUG
3061                       printf("%s recommends %s\n", solvid2str(pool, ip), solvid2str(pool, p));
3062 #endif
3063                       queue_push(&iq, p);
3064                     }
3065                 }
3066             }
3067         }
3068       if (!iq.count)
3069         {
3070           /* supplements pass */
3071           for (i = 0; i < installedq->count; i++)
3072             {
3073               ip = installedq->elements[i];
3074               s = pool->solvables + ip;
3075               if (!s->supplements)
3076                 continue;
3077               if (!MAPTST(&im, ip))
3078                 continue;
3079               supp = s->repo->idarraydata + s->supplements;
3080               while ((sup = *supp++) != 0)
3081                 if (!dep_possible(solv, sup, &im) && dep_possible(solv, sup, &installedm))
3082                   break;
3083               /* no longer supplemented, also erase */
3084               if (sup)
3085                 {
3086 #if FIND_INVOLVED_DEBUG
3087                   printf("%s supplemented\n", solvid2str(pool, ip));
3088 #endif
3089                   queue_push(&iq, ip);
3090                 }
3091             }
3092         }
3093     }
3094
3095   for (i = 0; i < installedq->count; i++)
3096     {
3097       ip = installedq->elements[i];
3098       if (MAPTST(&im, ip))
3099         queue_push(&iq, ip);
3100     }
3101
3102   while (iq.count)
3103     {
3104       ip = queue_shift(&iq);
3105       if (!MAPTST(&installedm, ip))
3106         continue;
3107       s = pool->solvables + ip;
3108 #if FIND_INVOLVED_DEBUG
3109       printf("bye %s\n", solvable2str(pool, s));
3110 #endif
3111       if (s->requires)
3112         {
3113           reqp = s->repo->idarraydata + s->requires;
3114           while ((req = *reqp++) != 0)
3115             {
3116               FOR_PROVIDES(p, pp, req)
3117                 {
3118                   if (!MAPTST(&im, p))
3119                     {
3120                       if (p == tp)
3121                         continue;
3122 #if FIND_INVOLVED_DEBUG
3123                       printf("%s requires %s\n", solvid2str(pool, ip), solvid2str(pool, p));
3124 #endif
3125                       MAPSET(&im, p);
3126                       queue_push(&iq, p);
3127                     }
3128                 }
3129             }
3130         }
3131       if (s->recommends)
3132         {
3133           reqp = s->repo->idarraydata + s->recommends;
3134           while ((req = *reqp++) != 0)
3135             {
3136               FOR_PROVIDES(p, pp, req)
3137                 {
3138                   if (!MAPTST(&im, p))
3139                     {
3140                       if (p == tp)
3141                         continue;
3142 #if FIND_INVOLVED_DEBUG
3143                       printf("%s recommends %s\n", solvid2str(pool, ip), solvid2str(pool, p));
3144 #endif
3145                       MAPSET(&im, p);
3146                       queue_push(&iq, p);
3147                     }
3148                 }
3149             }
3150         }
3151       if (!iq.count)
3152         {
3153           /* supplements pass */
3154           for (i = 0; i < installedq->count; i++)
3155             {
3156               ip = installedq->elements[i];
3157               if (ip == tp)
3158                 continue;
3159               s = pool->solvables + ip;
3160               if (!s->supplements)
3161                 continue;
3162               if (MAPTST(&im, ip))
3163                 continue;
3164               supp = s->repo->idarraydata + s->supplements;
3165               while ((sup = *supp++) != 0)
3166                 if (dep_possible(solv, sup, &im))
3167                   break;
3168               if (sup)
3169                 {
3170 #if FIND_INVOLVED_DEBUG
3171                   printf("%s supplemented\n", solvid2str(pool, ip));
3172 #endif
3173                   MAPSET(&im, ip);
3174                   queue_push(&iq, ip);
3175                 }
3176             }
3177         }
3178     }
3179
3180   queue_free(&iq);
3181
3182   /* convert map into result */
3183   for (i = 0; i < installedq->count; i++)
3184     {
3185       ip = installedq->elements[i];
3186       if (MAPTST(&im, ip))
3187         continue;
3188       if (ip == ts - pool->solvables)
3189         continue;
3190       queue_push(q, ip);
3191     }
3192   map_free(&im);
3193   map_free(&installedm);
3194   queue_free(&installedq_internal);
3195 }
3196 #endif
3197