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       /* disable last weak rule */
 979       solv->problems.count = oldproblemcount;
 980       solv->learnt_pool.count = oldlearntpoolcount;
 981       if (lastweak >= solv->jobrules && lastweak < solv->jobrules_end)
 982         v = -(solv->ruletojob.elements[lastweak - solv->jobrules] + 1);
 983       else
 984         v = lastweak;
 985       POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "disabling ");
 986       solver_printruleclass(solv, SAT_DEBUG_UNSOLVABLE, solv->rules + lastweak);
 987       if (lastweak >= solv->choicerules && lastweak < solv->choicerules_end)
 988         solver_disablechoicerules(solv, solv->rules + lastweak);
 989       solver_disableproblem(solv, v);
 990       if (v < 0)
 991         solver_reenablepolicyrules(solv, -(v + 1));
 992       solver_reset(solv);
 993       return 1;
 994     }
 995
 996   /* finish proof */
 997   queue_push(&solv->learnt_pool, 0);
 998   solv->problems.elements[oldproblemcount] = oldlearntpoolcount;
 999
1000   if (disablerules)
1001     {
1002       for (i = oldproblemcount + 1; i < solv->problems.count - 1; i++)
1003         solver_disableproblem(solv, solv->problems.elements[i]);
1004       /* XXX: might want to enable all weak rules again */
1005       solver_reset(solv);
1006       return 1;
1007     }
1008   POOL_DEBUG(SAT_DEBUG_UNSOLVABLE, "UNSOLVABLE\n");
1009   return 0;
1010 }
1011
1012
1013 /********************************************************************/
1014 /* Decision revert */
1015
1016 /*-------------------------------------------------------------------
1017  *
1018  * revert
1019  * revert decision at level
1020  */
1021
1022 static void
1023 revert(Solver *solv, int level)
1024 {
1025   Pool *pool = solv->pool;
1026   Id v, vv;
1027   while (solv->decisionq.count)
1028     {
1029       v = solv->decisionq.elements[solv->decisionq.count - 1];
1030       vv = v > 0 ? v : -v;
1031       if (solv->decisionmap[vv] <= level && solv->decisionmap[vv] >= -level)
1032         break;
1033       POOL_DEBUG(SAT_DEBUG_PROPAGATE, "reverting decision %d at %d\n", v, solv->decisionmap[vv]);
1034       if (v > 0 && solv->recommendations.count && v == solv->recommendations.elements[solv->recommendations.count - 1])
1035         solv->recommendations.count--;
1036       solv->decisionmap[vv] = 0;
1037       solv->decisionq.count--;
1038       solv->decisionq_why.count--;
1039       solv->propagate_index = solv->decisionq.count;
1040     }
1041   while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] <= -level)
1042     {
1043       solv->branches.count--;
1044       while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] >= 0)
1045         solv->branches.count--;
1046     }
1047   solv->recommends_index = -1;
1048 }
1049
1050
1051 /*-------------------------------------------------------------------
1052  *
1053  * watch2onhighest - put watch2 on literal with highest level
1054  */
1055
1056 static inline void
1057 watch2onhighest(Solver *solv, Rule *r)
1058 {
1059   int l, wl = 0;
1060   Id d, v, *dp;
1061
1062   d = r->d < 0 ? -r->d - 1 : r->d;
1063   if (!d)
1064     return;     /* binary rule, both watches are set */
1065   dp = solv->pool->whatprovidesdata + d;
1066   while ((v = *dp++) != 0)
1067     {
1068       l = solv->decisionmap[v < 0 ? -v : v];
1069       if (l < 0)
1070         l = -l;
1071       if (l > wl)
1072         {
1073           r->w2 = dp[-1];
1074           wl = l;
1075         }
1076     }
1077 }
1078
1079
1080 /*-------------------------------------------------------------------
1081  *
1082  * setpropagatelearn
1083  *
1084  * add free decision (solvable to install) to decisionq
1085  * increase level and propagate decision
1086  * return if no conflict.
1087  *
1088  * in conflict case, analyze conflict rule, add resulting
1089  * rule to learnt rule set, make decision from learnt
1090  * rule (always unit) and re-propagate.
1091  *
1092  * returns the new solver level or 0 if unsolvable
1093  *
1094  */
1095
1096 static int
1097 setpropagatelearn(Solver *solv, int level, Id decision, int disablerules, Id ruleid)
1098 {
1099   Pool *pool = solv->pool;
1100   Rule *r;
1101   Id p = 0, d = 0;
1102   int l, why;
1103
1104   assert(ruleid >= 0);
1105   if (decision)
1106     {
1107       level++;
1108       if (decision > 0)
1109         solv->decisionmap[decision] = level;
1110       else
1111         solv->decisionmap[-decision] = -level;
1112       queue_push(&solv->decisionq, decision);
1113       queue_push(&solv->decisionq_why, -ruleid);        /* <= 0 -> free decision */
1114     }
1115   for (;;)
1116     {
1117       r = propagate(solv, level);
1118       if (!r)
1119         break;
1120       if (level == 1)
1121         return analyze_unsolvable(solv, r, disablerules);
1122       POOL_DEBUG(SAT_DEBUG_ANALYZE, "conflict with rule #%d\n", (int)(r - solv->rules));
1123       l = analyze(solv, level, r, &p, &d, &why);        /* learnt rule in p and d */
1124       assert(l > 0 && l < level);
1125       POOL_DEBUG(SAT_DEBUG_ANALYZE, "reverting decisions (level %d -> %d)\n", level, l);
1126       level = l;
1127       revert(solv, level);
1128       r = solver_addrule(solv, p, d);
1129       assert(r);
1130       assert(solv->learnt_why.count == (r - solv->rules) - solv->learntrules);
1131       queue_push(&solv->learnt_why, why);
1132       if (d)
1133         {
1134           /* at least 2 literals, needs watches */
1135           watch2onhighest(solv, r);
1136           addwatches_rule(solv, r);
1137         }
1138       else
1139         {
1140           /* learnt rule is an assertion */
1141           queue_push(&solv->ruleassertions, r - solv->rules);
1142         }
1143       /* the new rule is unit by design */
1144       solv->decisionmap[p > 0 ? p : -p] = p > 0 ? level : -level;
1145       queue_push(&solv->decisionq, p);
1146       queue_push(&solv->decisionq_why, r - solv->rules);
1147       IF_POOLDEBUG (SAT_DEBUG_ANALYZE)
1148         {
1149           POOL_DEBUG(SAT_DEBUG_ANALYZE, "decision: ");
1150           solver_printruleelement(solv, SAT_DEBUG_ANALYZE, 0, p);
1151           POOL_DEBUG(SAT_DEBUG_ANALYZE, "new rule: ");
1152           solver_printrule(solv, SAT_DEBUG_ANALYZE, r);
1153         }
1154     }
1155   return level;
1156 }
1157
1158
1159 /*-------------------------------------------------------------------
1160  *
1161  * select and install
1162  *
1163  * install best package from the queue. We add an extra package, inst, if
1164  * provided. See comment in weak install section.
1165  *
1166  * returns the new solver level or 0 if unsolvable
1167  *
1168  */
1169
1170 static int
1171 selectandinstall(Solver *solv, int level, Queue *dq, int disablerules, Id ruleid)
1172 {
1173   Pool *pool = solv->pool;
1174   Id p;
1175   int i;
1176
1177   if (dq->count > 1)
1178     policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
1179   if (dq->count > 1)
1180     {
1181       /* XXX: didn't we already do that? */
1182       /* XXX: shouldn't we prefer installed packages? */
1183       /* XXX: move to policy.c? */
1184       /* choose the supplemented one */
1185       for (i = 0; i < dq->count; i++)
1186         if (solver_is_supplementing(solv, pool->solvables + dq->elements[i]))
1187           {
1188             dq->elements[0] = dq->elements[i];
1189             dq->count = 1;
1190             break;
1191           }
1192     }
1193   if (dq->count > 1)
1194     {
1195       /* multiple candidates, open a branch */
1196       for (i = 1; i < dq->count; i++)
1197         queue_push(&solv->branches, dq->elements[i]);
1198       queue_push(&solv->branches, -level);
1199     }
1200   p = dq->elements[0];
1201
1202   POOL_DEBUG(SAT_DEBUG_POLICY, "installing %s\n", solvid2str(pool, p));
1203
1204   return setpropagatelearn(solv, level, p, disablerules, ruleid);
1205 }
1206
1207
1208 /********************************************************************/
1209 /* Main solver interface */
1210
1211
1212 /*-------------------------------------------------------------------
1213  *
1214  * solver_create
1215  * create solver structure
1216  *
1217  * pool: all available solvables
1218  * installed: installed Solvables
1219  *
1220  *
1221  * Upon solving, rules are created to flag the Solvables
1222  * of the 'installed' Repo as installed.
1223  */
1224
1225 Solver *
1226 solver_create(Pool *pool)
1227 {
1228   Solver *solv;
1229   solv = (Solver *)sat_calloc(1, sizeof(Solver));
1230   solv->pool = pool;
1231   solv->installed = pool->installed;
1232
1233   transaction_init(&solv->trans, pool);
1234   queue_init(&solv->ruletojob);
1235   queue_init(&solv->decisionq);
1236   queue_init(&solv->decisionq_why);
1237   queue_init(&solv->problems);
1238   queue_init(&solv->suggestions);
1239   queue_init(&solv->recommendations);
1240   queue_init(&solv->orphaned);
1241   queue_init(&solv->learnt_why);
1242   queue_init(&solv->learnt_pool);
1243   queue_init(&solv->branches);
1244   queue_init(&solv->covenantq);
1245   queue_init(&solv->weakruleq);
1246   queue_init(&solv->ruleassertions);
1247
1248   map_init(&solv->recommendsmap, pool->nsolvables);
1249   map_init(&solv->suggestsmap, pool->nsolvables);
1250   map_init(&solv->noupdate, solv->installed ? solv->installed->end - solv->installed->start : 0);
1251   solv->recommends_index = 0;
1252
1253   solv->decisionmap = (Id *)sat_calloc(pool->nsolvables, sizeof(Id));
1254   solv->nrules = 1;
1255   solv->rules = sat_extend_resize(solv->rules, solv->nrules, sizeof(Rule), RULES_BLOCK);
1256   memset(solv->rules, 0, sizeof(Rule));
1257
1258   return solv;
1259 }
1260
1261
1262 /*-------------------------------------------------------------------
1263  *
1264  * solver_free
1265  */
1266
1267 void
1268 solver_free(Solver *solv)
1269 {
1270   transaction_free(&solv->trans);
1271   queue_free(&solv->job);
1272   queue_free(&solv->ruletojob);
1273   queue_free(&solv->decisionq);
1274   queue_free(&solv->decisionq_why);
1275   queue_free(&solv->learnt_why);
1276   queue_free(&solv->learnt_pool);
1277   queue_free(&solv->problems);
1278   queue_free(&solv->solutions);
1279   queue_free(&solv->suggestions);
1280   queue_free(&solv->recommendations);
1281   queue_free(&solv->orphaned);
1282   queue_free(&solv->branches);
1283   queue_free(&solv->covenantq);
1284   queue_free(&solv->weakruleq);
1285   queue_free(&solv->ruleassertions);
1286
1287   map_free(&solv->recommendsmap);
1288   map_free(&solv->suggestsmap);
1289   map_free(&solv->noupdate);
1290   map_free(&solv->weakrulemap);
1291   map_free(&solv->noobsoletes);
1292
1293   map_free(&solv->updatemap);
1294   map_free(&solv->fixmap);
1295   map_free(&solv->dupmap);
1296   map_free(&solv->dupinvolvedmap);
1297   map_free(&solv->droporphanedmap);
1298   map_free(&solv->cleandepsmap);
1299
1300   sat_free(solv->decisionmap);
1301   sat_free(solv->rules);
1302   sat_free(solv->watches);
1303   sat_free(solv->obsoletes);
1304   sat_free(solv->obsoletes_data);
1305   sat_free(solv->multiversionupdaters);
1306   sat_free(solv->choicerules_ref);
1307   sat_free(solv);
1308 }
1309
1310
1311 /*-------------------------------------------------------------------
1312  *
1313  * solver_run_sat
1314  *
1315  * all rules have been set up, now actually run the solver
1316  *
1317  */
1318
1319 void
1320 solver_run_sat(Solver *solv, int disablerules, int doweak)
1321 {
1322   Queue dq;             /* local decisionqueue */
1323   Queue dqs;            /* local decisionqueue for supplements */
1324   int systemlevel;
1325   int level, olevel;
1326   Rule *r;
1327   int i, j, n;
1328   Solvable *s;
1329   Pool *pool = solv->pool;
1330   Id p, *dp;
1331   int minimizationsteps;
1332   int installedpos = solv->installed ? solv->installed->start : 0;
1333
1334   IF_POOLDEBUG (SAT_DEBUG_RULE_CREATION)
1335     {
1336       POOL_DEBUG (SAT_DEBUG_RULE_CREATION, "number of rules: %d\n", solv->nrules);
1337       for (i = 1; i < solv->nrules; i++)
1338         solver_printruleclass(solv, SAT_DEBUG_RULE_CREATION, solv->rules + i);
1339     }
1340
1341   POOL_DEBUG(SAT_DEBUG_SOLVER, "initial decisions: %d\n", solv->decisionq.count);
1342
1343   IF_POOLDEBUG (SAT_DEBUG_SCHUBI)
1344     solver_printdecisions(solv);
1345
1346   /* start SAT algorithm */
1347   level = 1;
1348   systemlevel = level + 1;
1349   POOL_DEBUG(SAT_DEBUG_SOLVER, "solving...\n");
1350
1351   queue_init(&dq);
1352   queue_init(&dqs);
1353
1354   /*
1355    * here's the main loop:
1356    * 1) propagate new decisions (only needed once)
1357    * 2) fulfill jobs
1358    * 3) try to keep installed packages
1359    * 4) fulfill all unresolved rules
1360    * 5) install recommended packages
1361    * 6) minimalize solution if we had choices
1362    * if we encounter a problem, we rewind to a safe level and restart
1363    * with step 1
1364    */
1365
1366   minimizationsteps = 0;
1367   for (;;)
1368     {
1369       /*
1370        * initial propagation of the assertions
1371        */
1372       if (level == 1)
1373         {
1374           POOL_DEBUG(SAT_DEBUG_PROPAGATE, "propagating (propagate_index: %d;  size decisionq: %d)...\n", solv->propagate_index, solv->decisionq.count);
1375           if ((r = propagate(solv, level)) != 0)
1376             {
1377               if (analyze_unsolvable(solv, r, disablerules))
1378                 continue;
1379               queue_free(&dq);
1380               queue_free(&dqs);
1381               return;
1382             }
1383         }
1384
1385       /*
1386        * resolve jobs first
1387        */
1388      if (level < systemlevel)
1389         {
1390           POOL_DEBUG(SAT_DEBUG_SOLVER, "resolving job rules\n");
1391           for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
1392             {
1393               Id l;
1394               if (r->d < 0)             /* ignore disabled rules */
1395                 continue;
1396               queue_empty(&dq);
1397               FOR_RULELITERALS(l, dp, r)
1398                 {
1399                   if (l < 0)
1400                     {
1401                       if (solv->decisionmap[-l] <= 0)
1402                         break;
1403                     }
1404                   else
1405                     {
1406                       if (solv->decisionmap[l] > 0)
1407                         break;
1408                       if (solv->decisionmap[l] == 0)
1409                         queue_push(&dq, l);
1410                     }
1411                 }
1412               if (l || !dq.count)
1413                 continue;
1414               /* prune to installed if not updating */
1415               if (dq.count > 1 && solv->installed && !solv->updatemap_all)
1416                 {
1417                   int j, k;
1418                   for (j = k = 0; j < dq.count; j++)
1419                     {
1420                       Solvable *s = pool->solvables + dq.elements[j];
1421                       if (s->repo == solv->installed)
1422                         {
1423                           dq.elements[k++] = dq.elements[j];
1424                           if (solv->updatemap.size && MAPTST(&solv->updatemap, dq.elements[j] - solv->installed->start))
1425                             {
1426                               k = 0;    /* package wants to be updated, do not prune */
1427                               break;
1428                             }
1429                         }
1430                     }
1431                   if (k)
1432                     dq.count = k;
1433                 }
1434               olevel = level;
1435               level = selectandinstall(solv, level, &dq, disablerules, i);
1436               if (level == 0)
1437                 {
1438                   queue_free(&dq);
1439                   queue_free(&dqs);
1440                   return;
1441                 }
1442               if (level <= olevel)
1443                 break;
1444             }
1445           systemlevel = level + 1;
1446           if (i < solv->jobrules_end)
1447             continue;
1448         }
1449
1450
1451       /*
1452        * installed packages
1453        */
1454       if (level < systemlevel && solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
1455         {
1456           Repo *installed = solv->installed;
1457           int pass;
1458
1459           POOL_DEBUG(SAT_DEBUG_SOLVER, "resolving installed packages\n");
1460           /* we use two passes if we need to update packages
1461            * to create a better user experience */
1462           for (pass = solv->updatemap.size ? 0 : 1; pass < 2; pass++)
1463             {
1464               int passlevel = level;
1465               /* start with installedpos, the position that gave us problems last time */
1466               for (i = installedpos, n = installed->start; n < installed->end; i++, n++)
1467                 {
1468                   Rule *rr;
1469                   Id d;
1470
1471                   if (i == installed->end)
1472                     i = installed->start;
1473                   s = pool->solvables + i;
1474                   if (s->repo != installed)
1475                     continue;
1476
1477                   if (solv->decisionmap[i] > 0)
1478                     continue;
1479                   if (!pass && solv->updatemap.size && !MAPTST(&solv->updatemap, i - installed->start))
1480                     continue;           /* updates first */
1481                   r = solv->rules + solv->updaterules + (i - installed->start);
1482                   rr = r;
1483                   if (!rr->p || rr->d < 0)      /* disabled -> look at feature rule */
1484                     rr -= solv->installed->end - solv->installed->start;
1485                   if (!rr->p)           /* identical to update rule? */
1486                     rr = r;
1487                   if (!rr->p)
1488                     continue;           /* orpaned package */
1489
1490                   /* XXX: noupdate check is probably no longer needed, as all jobs should
1491                    * already be satisfied */
1492                   /* Actually we currently still need it because of erase jobs */
1493                   /* if noupdate is set we do not look at update candidates */
1494                   queue_empty(&dq);
1495                   if (!MAPTST(&solv->noupdate, i - installed->start) && (solv->decisionmap[i] < 0 || solv->updatemap_all || (solv->updatemap.size && MAPTST(&solv->updatemap, i - installed->start)) || rr->p != i))
1496                     {
1497                       if (solv->noobsoletes.size && solv->multiversionupdaters
1498                              && (d = solv->multiversionupdaters[i - installed->start]) != 0)
1499                         {
1500                           /* special multiversion handling, make sure best version is chosen */
1501                           queue_push(&dq, i);
1502                           while ((p = pool->whatprovidesdata[d++]) != 0)
1503                             if (solv->decisionmap[p] >= 0)
1504                               queue_push(&dq, p);
1505                           policy_filter_unwanted(solv, &dq, POLICY_MODE_CHOOSE);
1506                           p = dq.elements[0];
1507                           if (p != i && solv->decisionmap[p] == 0)
1508                             {
1509                               rr = solv->rules + solv->featurerules + (i - solv->installed->start);
1510                               if (!rr->p)               /* update rule == feature rule? */
1511                                 rr = rr - solv->featurerules + solv->updaterules;
1512                               dq.count = 1;
1513                             }
1514                           else
1515                             dq.count = 0;
1516                         }
1517                       else
1518                         {
1519                           /* update to best package */
1520                           FOR_RULELITERALS(p, dp, rr)
1521                             {
1522                               if (solv->decisionmap[p] > 0)
1523                                 {
1524                                   dq.count = 0;         /* already fulfilled */
1525                                   break;
1526                                 }
1527                               if (!solv->decisionmap[p])
1528                                 queue_push(&dq, p);
1529                             }
1530                         }
1531                     }
1532                   /* install best version */
1533                   if (dq.count)
1534                     {
1535                       olevel = level;
1536                       level = selectandinstall(solv, level, &dq, disablerules, rr - solv->rules);
1537                       if (level == 0)
1538                         {
1539                           queue_free(&dq);
1540                           queue_free(&dqs);
1541                           return;
1542                         }
1543                       if (level <= olevel)
1544                         {
1545                           if (level == 1 || level < passlevel)
1546                             break;      /* trouble */
1547                           if (level < olevel)
1548                             n = installed->start;       /* redo all */
1549                           i--;
1550                           n--;
1551                           continue;
1552                         }
1553                     }
1554                   /* if still undecided keep package */
1555                   if (solv->decisionmap[i] == 0)
1556                     {
1557                       olevel = level;
1558                       if (solv->cleandepsmap.size && MAPTST(&solv->cleandepsmap, i - installed->start))
1559                         {
1560                           POOL_DEBUG(SAT_DEBUG_POLICY, "cleandeps erasing %s\n", solvid2str(pool, i));
1561                           level = setpropagatelearn(solv, level, -i, disablerules, 0);
1562                         }
1563                       else
1564                         {
1565                           POOL_DEBUG(SAT_DEBUG_POLICY, "keeping %s\n", solvid2str(pool, i));
1566                           level = setpropagatelearn(solv, level, i, disablerules, r - solv->rules);
1567                         }
1568                       if (level == 0)
1569                         {
1570                           queue_free(&dq);
1571                           queue_free(&dqs);
1572                           return;
1573                         }
1574                       if (level <= olevel)
1575                         {
1576                           if (level == 1 || level < passlevel)
1577                             break;      /* trouble */
1578                           if (level < olevel)
1579                             n = installed->start;       /* redo all */
1580                           i--;
1581                           n--;
1582                           continue; /* retry with learnt rule */
1583                         }
1584                     }
1585                 }
1586               if (n < installed->end)
1587                 {
1588                   installedpos = i;     /* retry problem solvable next time */
1589                   break;                /* ran into trouble */
1590                 }
1591               installedpos = installed->start;  /* reset installedpos */
1592             }
1593           systemlevel = level + 1;
1594           if (pass < 2)
1595             continue;           /* had trouble, retry */
1596         }
1597
1598       if (level < systemlevel)
1599         systemlevel = level;
1600
1601       /*
1602        * decide
1603        */
1604       POOL_DEBUG(SAT_DEBUG_POLICY, "deciding unresolved rules\n");
1605       for (i = 1, n = 1; n < solv->nrules; i++, n++)
1606         {
1607           if (i == solv->nrules)
1608             i = 1;
1609           r = solv->rules + i;
1610           if (r->d < 0)         /* ignore disabled rules */
1611             continue;
1612           queue_empty(&dq);
1613           if (r->d == 0)
1614             {
1615               /* binary or unary rule */
1616               /* need two positive undecided literals */
1617               if (r->p < 0 || r->w2 <= 0)
1618                 continue;
1619               if (solv->decisionmap[r->p] || solv->decisionmap[r->w2])
1620                 continue;
1621               queue_push(&dq, r->p);
1622               queue_push(&dq, r->w2);
1623             }
1624           else
1625             {
1626               /* make sure that
1627                * all negative literals are installed
1628                * no positive literal is installed
1629                * i.e. the rule is not fulfilled and we
1630                * just need to decide on the positive literals
1631                */
1632               if (r->p < 0)
1633                 {
1634                   if (solv->decisionmap[-r->p] <= 0)
1635                     continue;
1636                 }
1637               else
1638                 {
1639                   if (solv->decisionmap[r->p] > 0)
1640                     continue;
1641                   if (solv->decisionmap[r->p] == 0)
1642                     queue_push(&dq, r->p);
1643                 }
1644               dp = pool->whatprovidesdata + r->d;
1645               while ((p = *dp++) != 0)
1646                 {
1647                   if (p < 0)
1648                     {
1649                       if (solv->decisionmap[-p] <= 0)
1650                         break;
1651                     }
1652                   else
1653                     {
1654                       if (solv->decisionmap[p] > 0)
1655                         break;
1656                       if (solv->decisionmap[p] == 0)
1657                         queue_push(&dq, p);
1658                     }
1659                 }
1660               if (p)
1661                 continue;
1662             }
1663           IF_POOLDEBUG (SAT_DEBUG_PROPAGATE)
1664             {
1665               POOL_DEBUG(SAT_DEBUG_PROPAGATE, "unfulfilled ");
1666               solver_printruleclass(solv, SAT_DEBUG_PROPAGATE, r);
1667             }
1668           /* dq.count < 2 cannot happen as this means that
1669            * the rule is unit */
1670           assert(dq.count > 1);
1671
1672           olevel = level;
1673           level = selectandinstall(solv, level, &dq, disablerules, r - solv->rules);
1674           if (level == 0)
1675             {
1676               queue_free(&dq);
1677               queue_free(&dqs);
1678               return;
1679             }
1680           if (level < systemlevel || level == 1)
1681             break;              /* trouble */
1682           /* something changed, so look at all rules again */
1683           n = 0;
1684         }
1685
1686       if (n != solv->nrules)    /* ran into trouble, restart */
1687         continue;
1688
1689       /* at this point we have a consistent system. now do the extras... */
1690
1691       if (doweak)
1692         {
1693           int qcount;
1694
1695           POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended packages\n");
1696           queue_empty(&dq);     /* recommended packages */
1697           queue_empty(&dqs);    /* supplemented packages */
1698           for (i = 1; i < pool->nsolvables; i++)
1699             {
1700               if (solv->decisionmap[i] < 0)
1701                 continue;
1702               if (solv->decisionmap[i] > 0)
1703                 {
1704                   /* installed, check for recommends */
1705                   Id *recp, rec, pp, p;
1706                   s = pool->solvables + i;
1707                   if (solv->ignorealreadyrecommended && s->repo == solv->installed)
1708                     continue;
1709                   /* XXX need to special case AND ? */
1710                   if (s->recommends)
1711                     {
1712                       recp = s->repo->idarraydata + s->recommends;
1713                       while ((rec = *recp++) != 0)
1714                         {
1715                           qcount = dq.count;
1716                           FOR_PROVIDES(p, pp, rec)
1717                             {
1718                               if (solv->decisionmap[p] > 0)
1719                                 {
1720                                   dq.count = qcount;
1721                                   break;
1722                                 }
1723                               else if (solv->decisionmap[p] == 0)
1724                                 {
1725                                   if (solv->dupmap_all && solv->installed && pool->solvables[p].repo == solv->installed && (solv->droporphanedmap_all || (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))))
1726                                     continue;
1727                                   queue_pushunique(&dq, p);
1728                                 }
1729                             }
1730                         }
1731                     }
1732                 }
1733               else
1734                 {
1735                   s = pool->solvables + i;
1736                   if (!s->supplements)
1737                     continue;
1738                   if (!pool_installable(pool, s))
1739                     continue;
1740                   if (!solver_is_supplementing(solv, s))
1741                     continue;
1742                   if (solv->dupmap_all && solv->installed && s->repo == solv->installed && (solv->droporphanedmap_all || (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, i - solv->installed->start))))
1743                     continue;
1744                   queue_push(&dqs, i);
1745                 }
1746             }
1747
1748           /* filter out all packages obsoleted by installed packages */
1749           /* this is no longer needed if we have reverse obsoletes */
1750           if ((dqs.count || dq.count) && solv->installed)
1751             {
1752               Map obsmap;
1753               Id obs, *obsp, po, ppo;
1754
1755               map_init(&obsmap, pool->nsolvables);
1756               for (p = solv->installed->start; p < solv->installed->end; p++)
1757                 {
1758                   s = pool->solvables + p;
1759                   if (s->repo != solv->installed || !s->obsoletes)
1760                     continue;
1761                   if (solv->decisionmap[p] <= 0)
1762                     continue;
1763                   if (solv->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
1764                     continue;
1765                   obsp = s->repo->idarraydata + s->obsoletes;
1766                   /* foreach obsoletes */
1767                   while ((obs = *obsp++) != 0)
1768                     FOR_PROVIDES(po, ppo, obs)
1769                       MAPSET(&obsmap, po);
1770                 }
1771               for (i = j = 0; i < dqs.count; i++)
1772                 if (!MAPTST(&obsmap, dqs.elements[i]))
1773                   dqs.elements[j++] = dqs.elements[i];
1774               dqs.count = j;
1775               for (i = j = 0; i < dq.count; i++)
1776                 if (!MAPTST(&obsmap, dq.elements[i]))
1777                   dq.elements[j++] = dq.elements[i];
1778               dq.count = j;
1779               map_free(&obsmap);
1780             }
1781
1782           /* filter out all already supplemented packages if requested */
1783           if (solv->ignorealreadyrecommended && dqs.count)
1784             {
1785               /* turn off all new packages */
1786               for (i = 0; i < solv->decisionq.count; i++)
1787                 {
1788                   p = solv->decisionq.elements[i];
1789                   if (p < 0)
1790                     continue;
1791                   s = pool->solvables + p;
1792                   if (s->repo && s->repo != solv->installed)
1793                     solv->decisionmap[p] = -solv->decisionmap[p];
1794                 }
1795               /* filter out old supplements */
1796               for (i = j = 0; i < dqs.count; i++)
1797                 {
1798                   p = dqs.elements[i];
1799                   s = pool->solvables + p;
1800                   if (!s->supplements)
1801                     continue;
1802                   if (!solver_is_supplementing(solv, s))
1803                     dqs.elements[j++] = p;
1804                 }
1805               dqs.count = j;
1806               /* undo turning off */
1807               for (i = 0; i < solv->decisionq.count; i++)
1808                 {
1809                   p = solv->decisionq.elements[i];
1810                   if (p < 0)
1811                     continue;
1812                   s = pool->solvables + p;
1813                   if (s->repo && s->repo != solv->installed)
1814                     solv->decisionmap[p] = -solv->decisionmap[p];
1815                 }
1816             }
1817
1818           /* multiversion doesn't mix well with supplements.
1819            * filter supplemented packages where we already decided
1820            * to install a different version (see bnc#501088) */
1821           if (dqs.count && solv->noobsoletes.size)
1822             {
1823               for (i = j = 0; i < dqs.count; i++)
1824                 {
1825                   p = dqs.elements[i];
1826                   if (MAPTST(&solv->noobsoletes, p))
1827                     {
1828                       Id p2, pp2;
1829                       s = pool->solvables + p;
1830                       FOR_PROVIDES(p2, pp2, s->name)
1831                         if (solv->decisionmap[p2] > 0 && pool->solvables[p2].name == s->name)
1832                           break;
1833                       if (p2)
1834                         continue;       /* ignore this package */
1835                     }
1836                   dqs.elements[j++] = p;
1837                 }
1838               dqs.count = j;
1839             }
1840
1841           /* make dq contain both recommended and supplemented pkgs */
1842           if (dqs.count)
1843             {
1844               for (i = 0; i < dqs.count; i++)
1845                 queue_pushunique(&dq, dqs.elements[i]);
1846             }
1847
1848           if (dq.count)
1849             {
1850               Map dqmap;
1851               int decisioncount = solv->decisionq.count;
1852
1853               if (dq.count == 1)
1854                 {
1855                   /* simple case, just one package. no need to choose  */
1856                   p = dq.elements[0];
1857                   if (dqs.count)
1858                     POOL_DEBUG(SAT_DEBUG_POLICY, "installing supplemented %s\n", solvid2str(pool, p));
1859                   else
1860                     POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended %s\n", solvid2str(pool, p));
1861                   queue_push(&solv->recommendations, p);
1862                   level = setpropagatelearn(solv, level, p, 0, 0);
1863                   continue;     /* back to main loop */
1864                 }
1865
1866               /* filter packages, this gives us the best versions */
1867               policy_filter_unwanted(solv, &dq, POLICY_MODE_RECOMMEND);
1868
1869               /* create map of result */
1870               map_init(&dqmap, pool->nsolvables);
1871               for (i = 0; i < dq.count; i++)
1872                 MAPSET(&dqmap, dq.elements[i]);
1873
1874               /* install all supplemented packages */
1875               for (i = 0; i < dqs.count; i++)
1876                 {
1877                   p = dqs.elements[i];
1878                   if (solv->decisionmap[p] || !MAPTST(&dqmap, p))
1879                     continue;
1880                   POOL_DEBUG(SAT_DEBUG_POLICY, "installing supplemented %s\n", solvid2str(pool, p));
1881                   queue_push(&solv->recommendations, p);
1882                   olevel = level;
1883                   level = setpropagatelearn(solv, level, p, 0, 0);
1884                   if (level <= olevel)
1885                     break;
1886                 }
1887               if (i < dqs.count || solv->decisionq.count < decisioncount)
1888                 {
1889                   map_free(&dqmap);
1890                   continue;
1891                 }
1892
1893               /* install all recommended packages */
1894               /* more work as we want to created branches if multiple
1895                * choices are valid */
1896               for (i = 0; i < decisioncount; i++)
1897                 {
1898                   Id rec, *recp, pp;
1899                   p = solv->decisionq.elements[i];
1900                   if (p < 0)
1901                     continue;
1902                   s = pool->solvables + p;
1903                   if (!s->repo || (solv->ignorealreadyrecommended && s->repo == solv->installed))
1904                     continue;
1905                   if (!s->recommends)
1906                     continue;
1907                   recp = s->repo->idarraydata + s->recommends;
1908                   while ((rec = *recp++) != 0)
1909                     {
1910                       queue_empty(&dq);
1911                       FOR_PROVIDES(p, pp, rec)
1912                         {
1913                           if (solv->decisionmap[p] > 0)
1914                             {
1915                               dq.count = 0;
1916                               break;
1917                             }
1918                           else if (solv->decisionmap[p] == 0 && MAPTST(&dqmap, p))
1919                             queue_pushunique(&dq, p);
1920                         }
1921                       if (!dq.count)
1922                         continue;
1923                       if (dq.count > 1)
1924                         {
1925                           /* multiple candidates, open a branch */
1926                           for (i = 1; i < dq.count; i++)
1927                             queue_push(&solv->branches, dq.elements[i]);
1928                           queue_push(&solv->branches, -level);
1929                         }
1930                       p = dq.elements[0];
1931                       POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended %s\n", solvid2str(pool, p));
1932                       queue_push(&solv->recommendations, p);
1933                       olevel = level;
1934                       level = setpropagatelearn(solv, level, p, 0, 0);
1935                       if (level <= olevel || solv->decisionq.count < decisioncount)
1936                         break;  /* we had to revert some decisions */
1937                     }
1938                   if (rec)
1939                     break;      /* had a problem above, quit loop */
1940                 }
1941               map_free(&dqmap);
1942
1943               continue;         /* back to main loop so that all deps are checked */
1944             }
1945         }
1946
1947      if (solv->dupmap_all && solv->installed)
1948         {
1949           int installedone = 0;
1950
1951           /* let's see if we can install some unsupported package */
1952           POOL_DEBUG(SAT_DEBUG_SOLVER, "deciding orphaned packages\n");
1953           for (i = 0; i < solv->orphaned.count; i++)
1954             {
1955               p = solv->orphaned.elements[i];
1956               if (solv->decisionmap[p])
1957                 continue;       /* already decided */
1958               olevel = level;
1959               if (solv->droporphanedmap_all)
1960                 continue;
1961               if (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))
1962                 continue;
1963               POOL_DEBUG(SAT_DEBUG_SOLVER, "keeping orphaned %s\n", solvid2str(pool, p));
1964               level = setpropagatelearn(solv, level, p, 0, 0);
1965               installedone = 1;
1966               if (level < olevel)
1967                 break;
1968             }
1969           if (installedone || i < solv->orphaned.count)
1970             continue;           /* back to main loop */
1971           for (i = 0; i < solv->orphaned.count; i++)
1972             {
1973               p = solv->orphaned.elements[i];
1974               if (solv->decisionmap[p])
1975                 continue;       /* already decided */
1976               POOL_DEBUG(SAT_DEBUG_SOLVER, "removing orphaned %s\n", solvid2str(pool, p));
1977               olevel = level;
1978               level = setpropagatelearn(solv, level, -p, 0, 0);
1979               if (level < olevel)
1980                 break;
1981             }
1982           if (i < solv->orphaned.count)
1983             continue;           /* back to main loop */
1984         }
1985
1986      if (solv->solution_callback)
1987         {
1988           solv->solution_callback(solv, solv->solution_callback_data);
1989           if (solv->branches.count)
1990             {
1991               int i = solv->branches.count - 1;
1992               int l = -solv->branches.elements[i];
1993               Id why;
1994
1995               for (; i > 0; i--)
1996                 if (solv->branches.elements[i - 1] < 0)
1997                   break;
1998               p = solv->branches.elements[i];
1999               POOL_DEBUG(SAT_DEBUG_SOLVER, "branching with %s\n", solvid2str(pool, p));
2000               queue_empty(&dq);
2001               for (j = i + 1; j < solv->branches.count; j++)
2002                 queue_push(&dq, solv->branches.elements[j]);
2003               solv->branches.count = i;
2004               level = l;
2005               revert(solv, level);
2006               if (dq.count > 1)
2007                 for (j = 0; j < dq.count; j++)
2008                   queue_push(&solv->branches, dq.elements[j]);
2009               olevel = level;
2010               why = -solv->decisionq_why.elements[solv->decisionq_why.count];
2011               assert(why >= 0);
2012               level = setpropagatelearn(solv, level, p, disablerules, why);
2013               if (level == 0)
2014                 {
2015                   queue_free(&dq);
2016                   queue_free(&dqs);
2017                   return;
2018                 }
2019               continue;
2020             }
2021           /* all branches done, we're finally finished */
2022           break;
2023         }
2024
2025       /* minimization step */
2026      if (solv->branches.count)
2027         {
2028           int l = 0, lasti = -1, lastl = -1;
2029           Id why;
2030
2031           p = 0;
2032           for (i = solv->branches.count - 1; i >= 0; i--)
2033             {
2034               p = solv->branches.elements[i];
2035               if (p < 0)
2036                 l = -p;
2037               else if (p > 0 && solv->decisionmap[p] > l + 1)
2038                 {
2039                   lasti = i;
2040                   lastl = l;
2041                 }
2042             }
2043           if (lasti >= 0)
2044             {
2045               /* kill old solvable so that we do not loop */
2046               p = solv->branches.elements[lasti];
2047               solv->branches.elements[lasti] = 0;
2048               POOL_DEBUG(SAT_DEBUG_SOLVER, "minimizing %d -> %d with %s\n", solv->decisionmap[p], lastl, solvid2str(pool, p));
2049               minimizationsteps++;
2050
2051               level = lastl;
2052               revert(solv, level);
2053               why = -solv->decisionq_why.elements[solv->decisionq_why.count];
2054               assert(why >= 0);
2055               olevel = level;
2056               level = setpropagatelearn(solv, level, p, disablerules, why);
2057               if (level == 0)
2058                 {
2059                   queue_free(&dq);
2060                   queue_free(&dqs);
2061                   return;
2062                 }
2063               continue;         /* back to main loop */
2064             }
2065         }
2066       /* no minimization found, we're finally finished! */
2067       break;
2068     }
2069
2070   POOL_DEBUG(SAT_DEBUG_STATS, "solver statistics: %d learned rules, %d unsolvable, %d minimization steps\n", solv->stats_learned, solv->stats_unsolvable, minimizationsteps);
2071
2072   POOL_DEBUG(SAT_DEBUG_STATS, "done solving.\n\n");
2073   queue_free(&dq);
2074   queue_free(&dqs);
2075 #if 0
2076   solver_printdecisionq(solv, SAT_DEBUG_RESULT);
2077 #endif
2078 }
2079
2080
2081 /*-------------------------------------------------------------------
2082  *
2083  * remove disabled conflicts
2084  *
2085  * purpose: update the decisionmap after some rules were disabled.
2086  * this is used to calculate the suggested/recommended package list.
2087  * Also returns a "removed" list to undo the discisionmap changes.
2088  */
2089
2090 static void
2091 removedisabledconflicts(Solver *solv, Queue *removed)
2092 {
2093   Pool *pool = solv->pool;
2094   int i, n;
2095   Id p, why, *dp;
2096   Id new;
2097   Rule *r;
2098   Id *decisionmap = solv->decisionmap;
2099
2100   POOL_DEBUG(SAT_DEBUG_SCHUBI, "removedisabledconflicts\n");
2101   queue_empty(removed);
2102   for (i = 0; i < solv->decisionq.count; i++)
2103     {
2104       p = solv->decisionq.elements[i];
2105       if (p > 0)
2106         continue;       /* conflicts only, please */
2107       why = solv->decisionq_why.elements[i];
2108       if (why == 0)
2109         {
2110           /* no rule involved, must be a orphan package drop */
2111           continue;
2112         }
2113       /* we never do conflicts on free decisions, so there
2114        * must have been an unit rule */
2115       assert(why > 0);
2116       r = solv->rules + why;
2117       if (r->d < 0 && decisionmap[-p])
2118         {
2119           /* rule is now disabled, remove from decisionmap */
2120           POOL_DEBUG(SAT_DEBUG_SCHUBI, "removing conflict for package %s[%d]\n", solvid2str(pool, -p), -p);
2121           queue_push(removed, -p);
2122           queue_push(removed, decisionmap[-p]);
2123           decisionmap[-p] = 0;
2124         }
2125     }
2126   if (!removed->count)
2127     return;
2128   /* we removed some confliced packages. some of them might still
2129    * be in conflict, so search for unit rules and re-conflict */
2130   new = 0;
2131   for (i = n = 1, r = solv->rules + i; n < solv->nrules; i++, r++, n++)
2132     {
2133       if (i == solv->nrules)
2134         {
2135           i = 1;
2136           r = solv->rules + i;
2137         }
2138       if (r->d < 0)
2139         continue;
2140       if (!r->w2)
2141         {
2142           if (r->p < 0 && !decisionmap[-r->p])
2143             new = r->p;
2144         }
2145       else if (!r->d)
2146         {
2147           /* binary rule */
2148           if (r->p < 0 && decisionmap[-r->p] == 0 && DECISIONMAP_FALSE(r->w2))
2149             new = r->p;
2150           else if (r->w2 < 0 && decisionmap[-r->w2] == 0 && DECISIONMAP_FALSE(r->p))
2151             new = r->w2;
2152         }
2153       else
2154         {
2155           if (r->p < 0 && decisionmap[-r->p] == 0)
2156             new = r->p;
2157           if (new || DECISIONMAP_FALSE(r->p))
2158             {
2159               dp = pool->whatprovidesdata + r->d;
2160               while ((p = *dp++) != 0)
2161                 {
2162                   if (new && p == new)
2163                     continue;
2164                   if (p < 0 && decisionmap[-p] == 0)
2165                     {
2166                       if (new)
2167                         {
2168                           new = 0;
2169                           break;
2170                         }
2171                       new = p;
2172                     }
2173                   else if (!DECISIONMAP_FALSE(p))
2174                     {
2175                       new = 0;
2176                       break;
2177                     }
2178                 }
2179             }
2180         }
2181       if (new)
2182         {
2183           POOL_DEBUG(SAT_DEBUG_SCHUBI, "re-conflicting package %s[%d]\n", solvid2str(pool, -new), -new);
2184           decisionmap[-new] = -1;
2185           new = 0;
2186           n = 0;        /* redo all rules */
2187         }
2188     }
2189 }
2190
2191 static inline void
2192 undo_removedisabledconflicts(Solver *solv, Queue *removed)
2193 {
2194   int i;
2195   for (i = 0; i < removed->count; i += 2)
2196     solv->decisionmap[removed->elements[i]] = removed->elements[i + 1];
2197 }
2198
2199
2200 /*-------------------------------------------------------------------
2201  *
2202  * weaken solvable dependencies
2203  */
2204
2205 static void
2206 weaken_solvable_deps(Solver *solv, Id p)
2207 {
2208   int i;
2209   Rule *r;
2210
2211   for (i = 1, r = solv->rules + i; i < solv->rpmrules_end; i++, r++)
2212     {
2213       if (r->p != -p)
2214         continue;
2215       if ((r->d == 0 || r->d == -1) && r->w2 < 0)
2216         continue;       /* conflict */
2217       queue_push(&solv->weakruleq, i);
2218     }
2219 }
2220
2221
2222 /********************************************************************/
2223 /* main() */
2224
2225
2226 static void
2227 findrecommendedsuggested(Solver *solv)
2228 {
2229   Pool *pool = solv->pool;
2230   Queue redoq, disabledq;
2231   int goterase, i;
2232   Solvable *s;
2233   Rule *r;
2234   Map obsmap;
2235
2236   map_init(&obsmap, pool->nsolvables);
2237   if (solv->installed)
2238     {
2239       Id obs, *obsp, p, po, ppo;
2240       for (p = solv->installed->start; p < solv->installed->end; p++)
2241         {
2242           s = pool->solvables + p;
2243           if (s->repo != solv->installed || !s->obsoletes)
2244             continue;
2245           if (solv->decisionmap[p] <= 0)
2246             continue;
2247           if (solv->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
2248             continue;
2249           obsp = s->repo->idarraydata + s->obsoletes;
2250           /* foreach obsoletes */
2251           while ((obs = *obsp++) != 0)
2252             FOR_PROVIDES(po, ppo, obs)
2253               MAPSET(&obsmap, po);
2254         }
2255     }
2256
2257   queue_init(&redoq);
2258   queue_init(&disabledq);
2259   goterase = 0;
2260   /* disable all erase jobs (including weak "keep uninstalled" rules) */
2261   for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
2262     {
2263       if (r->d < 0)     /* disabled ? */
2264         continue;
2265       if (r->p >= 0)    /* install job? */
2266         continue;
2267       queue_push(&disabledq, i);
2268       solver_disablerule(solv, r);
2269       goterase++;
2270     }
2271
2272   if (goterase)
2273     {
2274       enabledisablelearntrules(solv);
2275       removedisabledconflicts(solv, &redoq);
2276     }
2277
2278   /*
2279    * find recommended packages
2280    */
2281
2282   /* if redoq.count == 0 we already found all recommended in the
2283    * solver run */
2284   if (redoq.count || solv->dontinstallrecommended || !solv->dontshowinstalledrecommended || solv->ignorealreadyrecommended)
2285     {
2286       Id rec, *recp, p, pp;
2287
2288       /* create map of all recommened packages */
2289       solv->recommends_index = -1;
2290       MAPZERO(&solv->recommendsmap);
2291       for (i = 0; i < solv->decisionq.count; i++)
2292         {
2293           p = solv->decisionq.elements[i];
2294           if (p < 0)
2295             continue;
2296           s = pool->solvables + p;
2297           if (s->recommends)
2298             {
2299               recp = s->repo->idarraydata + s->recommends;
2300               while ((rec = *recp++) != 0)
2301                 {
2302                   FOR_PROVIDES(p, pp, rec)
2303                     if (solv->decisionmap[p] > 0)
2304                       break;
2305                   if (p)
2306                     {
2307                       if (!solv->dontshowinstalledrecommended)
2308                         {
2309                           FOR_PROVIDES(p, pp, rec)
2310                             if (solv->decisionmap[p] > 0)
2311                               MAPSET(&solv->recommendsmap, p);
2312                         }
2313                       continue; /* p != 0: already fulfilled */
2314                     }
2315                   FOR_PROVIDES(p, pp, rec)
2316                     MAPSET(&solv->recommendsmap, p);
2317                 }
2318             }
2319         }
2320       for (i = 1; i < pool->nsolvables; i++)
2321         {
2322           if (solv->decisionmap[i] < 0)
2323             continue;
2324           if (solv->decisionmap[i] > 0 && solv->dontshowinstalledrecommended)
2325             continue;
2326           if (MAPTST(&obsmap, i))
2327             continue;
2328           s = pool->solvables + i;
2329           if (!MAPTST(&solv->recommendsmap, i))
2330             {
2331               if (!s->supplements)
2332                 continue;
2333               if (!pool_installable(pool, s))
2334                 continue;
2335               if (!solver_is_supplementing(solv, s))
2336                 continue;
2337             }
2338           if (solv->dontinstallrecommended)
2339             queue_push(&solv->recommendations, i);
2340           else
2341             queue_pushunique(&solv->recommendations, i);
2342         }
2343       /* we use MODE_SUGGEST here so that repo prio is ignored */
2344       policy_filter_unwanted(solv, &solv->recommendations, POLICY_MODE_SUGGEST);
2345     }
2346
2347   /*
2348    * find suggested packages
2349    */
2350
2351   if (1)
2352     {
2353       Id sug, *sugp, p, pp;
2354
2355       /* create map of all suggests that are still open */
2356       solv->recommends_index = -1;
2357       MAPZERO(&solv->suggestsmap);
2358       for (i = 0; i < solv->decisionq.count; i++)
2359         {
2360           p = solv->decisionq.elements[i];
2361           if (p < 0)
2362             continue;
2363           s = pool->solvables + p;
2364           if (s->suggests)
2365             {
2366               sugp = s->repo->idarraydata + s->suggests;
2367               while ((sug = *sugp++) != 0)
2368                 {
2369                   FOR_PROVIDES(p, pp, sug)
2370                     if (solv->decisionmap[p] > 0)
2371                       break;
2372                   if (p)
2373                     {
2374                       if (!solv->dontshowinstalledrecommended)
2375                         {
2376                           FOR_PROVIDES(p, pp, sug)
2377                             if (solv->decisionmap[p] > 0)
2378                               MAPSET(&solv->suggestsmap, p);
2379                         }
2380                       continue; /* already fulfilled */
2381                     }
2382                   FOR_PROVIDES(p, pp, sug)
2383                     MAPSET(&solv->suggestsmap, p);
2384                 }
2385             }
2386         }
2387       for (i = 1; i < pool->nsolvables; i++)
2388         {
2389           if (solv->decisionmap[i] < 0)
2390             continue;
2391           if (solv->decisionmap[i] > 0 && solv->dontshowinstalledrecommended)
2392             continue;
2393           if (MAPTST(&obsmap, i))
2394             continue;
2395           s = pool->solvables + i;
2396           if (!MAPTST(&solv->suggestsmap, i))
2397             {
2398               if (!s->enhances)
2399                 continue;
2400               if (!pool_installable(pool, s))
2401                 continue;
2402               if (!solver_is_enhancing(solv, s))
2403                 continue;
2404             }
2405           queue_push(&solv->suggestions, i);
2406         }
2407       policy_filter_unwanted(solv, &solv->suggestions, POLICY_MODE_SUGGEST);
2408     }
2409
2410   /* undo removedisabledconflicts */
2411   if (redoq.count)
2412     undo_removedisabledconflicts(solv, &redoq);
2413   queue_free(&redoq);
2414
2415   /* undo job rule disabling */
2416   for (i = 0; i < disabledq.count; i++)
2417     solver_enablerule(solv, solv->rules + disabledq.elements[i]);
2418   queue_free(&disabledq);
2419   map_free(&obsmap);
2420 }
2421
2422 void
2423 solver_calculate_noobsmap(Pool *pool, Queue *job, Map *noobsmap)
2424 {
2425   int i;
2426   Id how, what, select;
2427   Id p, pp;
2428   for (i = 0; i < job->count; i += 2)
2429     {
2430       how = job->elements[i];
2431       if ((how & SOLVER_JOBMASK) != SOLVER_NOOBSOLETES)
2432         continue;
2433       what = job->elements[i + 1];
2434       select = how & SOLVER_SELECTMASK;
2435       if (!noobsmap->size)
2436         map_grow(noobsmap, pool->nsolvables);
2437       FOR_JOB_SELECT(p, pp, select, what)
2438         MAPSET(noobsmap, p);
2439     }
2440 }
2441
2442 /*
2443  * add a rule created by a job, record job number and weak flag
2444  */
2445 static inline void
2446 solver_addjobrule(Solver *solv, Id p, Id d, Id job, int weak)
2447 {
2448   solver_addrule(solv, p, d);
2449   queue_push(&solv->ruletojob, job);
2450   if (weak)
2451     queue_push(&solv->weakruleq, solv->nrules - 1);
2452 }
2453
2454 /*
2455  *
2456  * solve job queue
2457  *
2458  */
2459
2460 void
2461 solver_solve(Solver *solv, Queue *job)
2462 {
2463   Pool *pool = solv->pool;
2464   Repo *installed = solv->installed;
2465   int i;
2466   int oldnrules;
2467   Map addedmap;                /* '1' == have rpm-rules for solvable */
2468   Map installcandidatemap;
2469   Id how, what, select, name, weak, p, pp, d;
2470   Queue q;
2471   Solvable *s;
2472   Rule *r;
2473   int now, solve_start;
2474   int hasdupjob = 0;
2475
2476   solve_start = sat_timems(0);
2477
2478   /* log solver options */
2479   POOL_DEBUG(SAT_DEBUG_STATS, "solver started\n");
2480   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);
2481   POOL_DEBUG(SAT_DEBUG_STATS, "distupgrade=%d distupgrade_removeunsupported=%d\n", solv->distupgrade, solv->distupgrade_removeunsupported);
2482   POOL_DEBUG(SAT_DEBUG_STATS, "allowuninstall=%d, allowdowngrade=%d, allowarchchange=%d, allowvendorchange=%d\n", solv->allowuninstall, solv->allowdowngrade, solv->allowarchchange, solv->allowvendorchange);
2483   POOL_DEBUG(SAT_DEBUG_STATS, "promoteepoch=%d, novirtualconflicts=%d, allowselfconflicts=%d\n", pool->promoteepoch, pool->novirtualconflicts, pool->allowselfconflicts);
2484   POOL_DEBUG(SAT_DEBUG_STATS, "obsoleteusesprovides=%d, implicitobsoleteusesprovides=%d, obsoleteusescolors=%d\n", pool->obsoleteusesprovides, pool->implicitobsoleteusesprovides, pool->obsoleteusescolors);
2485   POOL_DEBUG(SAT_DEBUG_STATS, "dontinstallrecommended=%d, ignorealreadyrecommended=%d, dontshowinstalledrecommended=%d\n", solv->dontinstallrecommended, solv->ignorealreadyrecommended, solv->dontshowinstalledrecommended);
2486
2487   /* create whatprovides if not already there */
2488   if (!pool->whatprovides)
2489     pool_createwhatprovides(pool);
2490
2491   /* create obsolete index */
2492   policy_create_obsolete_index(solv);
2493
2494   /* remember job */
2495   queue_free(&solv->job);
2496   queue_init_clone(&solv->job, job);
2497
2498   /* initialize with legacy values */
2499   solv->fixmap_all = solv->fixsystem;
2500   solv->updatemap_all = solv->updatesystem;
2501   solv->droporphanedmap_all = solv->distupgrade_removeunsupported;
2502   solv->dupmap_all = solv->distupgrade;
2503
2504   /*
2505    * create basic rule set of all involved packages
2506    * use addedmap bitmap to make sure we don't create rules twice
2507    */
2508
2509   /* create noobsolete map if needed */
2510   solver_calculate_noobsmap(pool, job, &solv->noobsoletes);
2511
2512   map_init(&addedmap, pool->nsolvables);
2513   MAPSET(&addedmap, SYSTEMSOLVABLE);
2514
2515   map_init(&installcandidatemap, pool->nsolvables);
2516   queue_init(&q);
2517
2518   now = sat_timems(0);
2519   /*
2520    * create rules for all package that could be involved with the solving
2521    * so called: rpm rules
2522    *
2523    */
2524   if (installed)
2525     {
2526       /* check for update/verify jobs as they need to be known early */
2527       for (i = 0; i < job->count; i += 2)
2528         {
2529           how = job->elements[i];
2530           what = job->elements[i + 1];
2531           select = how & SOLVER_SELECTMASK;
2532           switch (how & SOLVER_JOBMASK)
2533             {
2534             case SOLVER_VERIFY:
2535               if (select == SOLVER_SOLVABLE_ALL)
2536                 solv->fixmap_all = 1;
2537               FOR_JOB_SELECT(p, pp, select, what)
2538                 {
2539                   s = pool->solvables + p;
2540                   if (!solv->installed || s->repo != solv->installed)
2541                     continue;
2542                   if (!solv->fixmap.size)
2543                     map_grow(&solv->fixmap, solv->installed->end - solv->installed->start);
2544                   MAPSET(&solv->fixmap, p - solv->installed->start);
2545                 }
2546               break;
2547             case SOLVER_UPDATE:
2548               if (select == SOLVER_SOLVABLE_ALL)
2549                 solv->updatemap_all = 1;
2550               FOR_JOB_SELECT(p, pp, select, what)
2551                 {
2552                   s = pool->solvables + p;
2553                   if (!solv->installed || s->repo != solv->installed)
2554                     continue;
2555                   if (!solv->updatemap.size)
2556                     map_grow(&solv->updatemap, solv->installed->end - solv->installed->start);
2557                   MAPSET(&solv->updatemap, p - solv->installed->start);
2558                 }
2559               break;
2560             default:
2561               break;
2562             }
2563         }
2564
2565       oldnrules = solv->nrules;
2566       POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for installed solvables ***\n");
2567       FOR_REPO_SOLVABLES(installed, p, s)
2568         solver_addrpmrulesforsolvable(solv, s, &addedmap);
2569       POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules for installed solvables\n", solv->nrules - oldnrules);
2570       POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for updaters of installed solvables ***\n");
2571       oldnrules = solv->nrules;
2572       FOR_REPO_SOLVABLES(installed, p, s)
2573         solver_addrpmrulesforupdaters(solv, s, &addedmap, 1);
2574       POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules for updaters of installed solvables\n", solv->nrules - oldnrules);
2575     }
2576
2577   /*
2578    * create rules for all packages involved in the job
2579    * (to be installed or removed)
2580    */
2581
2582   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for packages involved with a job ***\n");
2583   oldnrules = solv->nrules;
2584   for (i = 0; i < job->count; i += 2)
2585     {
2586       how = job->elements[i];
2587       what = job->elements[i + 1];
2588       select = how & SOLVER_SELECTMASK;
2589
2590       switch (how & SOLVER_JOBMASK)
2591         {
2592         case SOLVER_INSTALL:
2593           FOR_JOB_SELECT(p, pp, select, what)
2594             {
2595               MAPSET(&installcandidatemap, p);
2596               solver_addrpmrulesforsolvable(solv, pool->solvables + p, &addedmap);
2597             }
2598           break;
2599         case SOLVER_DISTUPGRADE:
2600           if (select == SOLVER_SOLVABLE_ALL)
2601             {
2602               solv->dupmap_all = 1;
2603               solv->updatemap_all = 1;
2604             }
2605           if (!solv->dupmap_all)
2606             hasdupjob = 1;
2607           break;
2608         default:
2609           break;
2610         }
2611     }
2612   POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules for packages involved in a job\n", solv->nrules - oldnrules);
2613
2614
2615   /*
2616    * add rules for suggests, enhances
2617    */
2618   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** create rpm rules for suggested/enhanced packages ***\n");
2619   oldnrules = solv->nrules;
2620   solver_addrpmrulesforweak(solv, &addedmap);
2621   POOL_DEBUG(SAT_DEBUG_STATS, "added %d rpm rules because of weak dependencies\n", solv->nrules - oldnrules);
2622
2623   /*
2624    * first pass done, we now have all the rpm rules we need.
2625    * unify existing rules before going over all job rules and
2626    * policy rules.
2627    * at this point the system is always solvable,
2628    * as an empty system (remove all packages) is a valid solution
2629    */
2630
2631   IF_POOLDEBUG (SAT_DEBUG_STATS)
2632     {
2633       int possible = 0, installable = 0;
2634       for (i = 1; i < pool->nsolvables; i++)
2635         {
2636           if (pool_installable(pool, pool->solvables + i))
2637             installable++;
2638           if (MAPTST(&addedmap, i))
2639             possible++;
2640         }
2641       POOL_DEBUG(SAT_DEBUG_STATS, "%d of %d installable solvables considered for solving\n", possible, installable);
2642     }
2643
2644   solver_unifyrules(solv);                          /* remove duplicate rpm rules */
2645   solv->rpmrules_end = solv->nrules;              /* mark end of rpm rules */
2646
2647   POOL_DEBUG(SAT_DEBUG_STATS, "rpm rule memory usage: %d K\n", solv->nrules * (int)sizeof(Rule) / 1024);
2648   POOL_DEBUG(SAT_DEBUG_STATS, "rpm rule creation took %d ms\n", sat_timems(now));
2649
2650   /* create dup maps if needed. We need the maps early to create our
2651    * update rules */
2652   if (hasdupjob)
2653     solver_createdupmaps(solv);
2654
2655   /*
2656    * create feature rules
2657    *
2658    * foreach installed:
2659    *   create assertion (keep installed, if no update available)
2660    *   or
2661    *   create update rule (A|update1(A)|update2(A)|...)
2662    *
2663    * those are used later on to keep a version of the installed packages in
2664    * best effort mode
2665    */
2666
2667   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** Add feature rules ***\n");
2668   solv->featurerules = solv->nrules;              /* mark start of feature rules */
2669   if (installed)
2670     {
2671       /* foreach possibly installed solvable */
2672       for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
2673         {
2674           if (s->repo != installed)
2675             {
2676               solver_addrule(solv, 0, 0);       /* create dummy rule */
2677               continue;
2678             }
2679           solver_addupdaterule(solv, s, 1);    /* allow s to be updated */
2680         }
2681       /* make sure we accounted for all rules */
2682       assert(solv->nrules - solv->featurerules == installed->end - installed->start);
2683     }
2684   solv->featurerules_end = solv->nrules;
2685
2686     /*
2687      * Add update rules for installed solvables
2688      *
2689      * almost identical to feature rules
2690      * except that downgrades/archchanges/vendorchanges are not allowed
2691      */
2692
2693   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** Add update rules ***\n");
2694   solv->updaterules = solv->nrules;
2695
2696   if (installed)
2697     { /* foreach installed solvables */
2698       /* we create all update rules, but disable some later on depending on the job */
2699       for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
2700         {
2701           Rule *sr;
2702
2703           if (s->repo != installed)
2704             {
2705               solver_addrule(solv, 0, 0);       /* create dummy rule */
2706               continue;
2707             }
2708           solver_addupdaterule(solv, s, 0);     /* allowall = 0: downgrades not allowed */
2709           /*
2710            * check for and remove duplicate
2711            */
2712           r = solv->rules + solv->nrules - 1;           /* r: update rule */
2713           sr = r - (installed->end - installed->start); /* sr: feature rule */
2714           /* it's orphaned if there is no feature rule or the feature rule
2715            * consists just of the installed package */
2716           if (!sr->p || (sr->p == i && !sr->d && !sr->w2))
2717             queue_push(&solv->orphaned, i);
2718           if (!r->p)
2719             {
2720               assert(solv->dupmap_all && !sr->p);
2721               continue;
2722             }
2723           if (!solver_samerule(solv, r, sr))
2724             {
2725               /* identical rule, kill unneeded one */
2726               if (solv->allowuninstall)
2727                 {
2728                   /* keep feature rule, make it weak */
2729                   memset(r, 0, sizeof(*r));
2730                   queue_push(&solv->weakruleq, sr - solv->rules);
2731                 }
2732               else
2733                 {
2734                   /* keep update rule */
2735                   memset(sr, 0, sizeof(*sr));
2736                 }
2737             }
2738           else if (solv->allowuninstall)
2739             {
2740               /* make both feature and update rule weak */
2741               queue_push(&solv->weakruleq, r - solv->rules);
2742               queue_push(&solv->weakruleq, sr - solv->rules);
2743             }
2744           else
2745             solver_disablerule(solv, sr);
2746         }
2747       /* consistency check: we added a rule for _every_ installed solvable */
2748       assert(solv->nrules - solv->updaterules == installed->end - installed->start);
2749     }
2750   solv->updaterules_end = solv->nrules;
2751
2752
2753   /*
2754    * now add all job rules
2755    */
2756
2757   POOL_DEBUG(SAT_DEBUG_SCHUBI, "*** Add JOB rules ***\n");
2758
2759   solv->jobrules = solv->nrules;
2760   for (i = 0; i < job->count; i += 2)
2761     {
2762       oldnrules = solv->nrules;
2763
2764       how = job->elements[i];
2765       what = job->elements[i + 1];
2766       weak = how & SOLVER_WEAK;
2767       select = how & SOLVER_SELECTMASK;
2768       switch (how & SOLVER_JOBMASK)
2769         {
2770         case SOLVER_INSTALL:
2771           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sinstall %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2772           if (select == SOLVER_SOLVABLE)
2773             {
2774               p = what;
2775               d = 0;
2776             }
2777           else
2778             {
2779               queue_empty(&q);
2780               FOR_JOB_SELECT(p, pp, select, what)
2781                 queue_push(&q, p);
2782               if (!q.count)
2783                 {
2784                   /* no candidate found, make this an impossible rule */
2785                   queue_push(&q, -SYSTEMSOLVABLE);
2786                 }
2787               p = queue_shift(&q);      /* get first candidate */
2788               d = !q.count ? 0 : pool_queuetowhatprovides(pool, &q);    /* internalize */
2789             }
2790           solver_addjobrule(solv, p, d, i, weak);
2791           break;
2792         case SOLVER_ERASE:
2793           POOL_DEBUG(SAT_DEBUG_JOB, "job: %s%serase %s\n", weak ? "weak " : "", how & SOLVER_CLEANDEPS ? "clean deps " : "", solver_select2str(pool, select, what));
2794           if ((how & SOLVER_CLEANDEPS) != 0 && !solv->cleandepsmap.size && solv->installed)
2795             map_grow(&solv->cleandepsmap, solv->installed->end - solv->installed->start);
2796           if (select == SOLVER_SOLVABLE && solv->installed && pool->solvables[what].repo == solv->installed)
2797             {
2798               /* special case for "erase a specific solvable": we also
2799                * erase all other solvables with that name, so that they
2800                * don't get picked up as replacement */
2801               /* XXX: look also at packages that obsolete this package? */
2802               name = pool->solvables[what].name;
2803               FOR_PROVIDES(p, pp, name)
2804                 {
2805                   if (p == what)
2806                     continue;
2807                   s = pool->solvables + p;
2808                   if (s->name != name)
2809                     continue;
2810                   /* keep other versions installed */
2811                   if (s->repo == solv->installed)
2812                     continue;
2813                   /* keep installcandidates of other jobs */
2814                   if (MAPTST(&installcandidatemap, p))
2815                     continue;
2816                   solver_addjobrule(solv, -p, 0, i, weak);      /* remove by id */
2817                 }
2818             }
2819           FOR_JOB_SELECT(p, pp, select, what)
2820             solver_addjobrule(solv, -p, 0, i, weak);
2821           break;
2822
2823         case SOLVER_UPDATE:
2824           POOL_DEBUG(SAT_DEBUG_JOB, "job: %supdate %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2825           break;
2826         case SOLVER_VERIFY:
2827           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sverify %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2828           break;
2829         case SOLVER_WEAKENDEPS:
2830           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sweaken deps %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2831           if (select != SOLVER_SOLVABLE)
2832             break;
2833           s = pool->solvables + what;
2834           weaken_solvable_deps(solv, what);
2835           break;
2836         case SOLVER_NOOBSOLETES:
2837           POOL_DEBUG(SAT_DEBUG_JOB, "job: %sno obsolete %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2838           break;
2839         case SOLVER_LOCK:
2840           POOL_DEBUG(SAT_DEBUG_JOB, "job: %slock %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2841           FOR_JOB_SELECT(p, pp, select, what)
2842             {
2843               s = pool->solvables + p;
2844               solver_addjobrule(solv, installed && s->repo == installed ? p : -p, 0, i, weak);
2845             }
2846           break;
2847         case SOLVER_DISTUPGRADE:
2848           POOL_DEBUG(SAT_DEBUG_JOB, "job: distupgrade %s\n", solver_select2str(pool, select, what));
2849           break;
2850         case SOLVER_DROP_ORPHANED:
2851           POOL_DEBUG(SAT_DEBUG_JOB, "job: drop orphaned %s\n", solver_select2str(pool, select, what));
2852           if (select == SOLVER_SOLVABLE_ALL)
2853             solv->droporphanedmap_all = 1;
2854           FOR_JOB_SELECT(p, pp, select, what)
2855             {
2856               s = pool->solvables + p;
2857               if (!installed || s->repo != installed)
2858                 continue;
2859               if (!solv->droporphanedmap.size)
2860                 map_grow(&solv->droporphanedmap, installed->end - installed->start);
2861               MAPSET(&solv->droporphanedmap, p - installed->start);
2862             }
2863           break;
2864         case SOLVER_USERINSTALLED:
2865           POOL_DEBUG(SAT_DEBUG_JOB, "job: user installed %s\n", solver_select2str(pool, select, what));
2866           break;
2867         default:
2868           POOL_DEBUG(SAT_DEBUG_JOB, "job: unknown job\n");
2869           break;
2870         }
2871
2872         /*
2873          * debug
2874          */
2875
2876       IF_POOLDEBUG (SAT_DEBUG_JOB)
2877         {
2878           int j;
2879           if (solv->nrules == oldnrules)
2880             POOL_DEBUG(SAT_DEBUG_JOB, " - no rule created\n");
2881           for (j = oldnrules; j < solv->nrules; j++)
2882             {
2883               POOL_DEBUG(SAT_DEBUG_JOB, " - job ");
2884               solver_printrule(solv, SAT_DEBUG_JOB, solv->rules + j);
2885             }
2886         }
2887     }
2888   assert(solv->ruletojob.count == solv->nrules - solv->jobrules);
2889   solv->jobrules_end = solv->nrules;
2890
2891   /* now create infarch and dup rules */
2892   if (!solv->noinfarchcheck)
2893     {
2894       solver_addinfarchrules(solv, &addedmap);
2895       if (pool->obsoleteusescolors)
2896         {
2897           /* currently doesn't work well with infarch rules, so make
2898            * them weak */
2899           for (i = solv->infarchrules; i < solv->infarchrules_end; i++)
2900             queue_push(&solv->weakruleq, i);
2901         }
2902     }
2903   else
2904     solv->infarchrules = solv->infarchrules_end = solv->nrules;
2905
2906   if (hasdupjob)
2907     {
2908       solver_addduprules(solv, &addedmap);
2909       solver_freedupmaps(solv); /* no longer needed */
2910     }
2911   else
2912     solv->duprules = solv->duprules_end = solv->nrules;
2913
2914   if (1)
2915     solver_addchoicerules(solv);
2916   else
2917     solv->choicerules = solv->choicerules_end = solv->nrules;
2918
2919   /* all rules created
2920    * --------------------------------------------------------------
2921    * prepare for solving
2922    */
2923
2924   /* free unneeded memory */
2925   map_free(&addedmap);
2926   map_free(&installcandidatemap);
2927   queue_free(&q);
2928
2929   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);
2930
2931   /* create weak map */
2932   map_init(&solv->weakrulemap, solv->nrules);
2933   for (i = 0; i < solv->weakruleq.count; i++)
2934     {
2935       p = solv->weakruleq.elements[i];
2936       MAPSET(&solv->weakrulemap, p);
2937     }
2938
2939   /* all new rules are learnt after this point */
2940   solv->learntrules = solv->nrules;
2941
2942   /* create watches chains */
2943   makewatches(solv);
2944
2945   /* create assertion index. it is only used to speed up
2946    * makeruledecsions() a bit */
2947   for (i = 1, r = solv->rules + i; i < solv->nrules; i++, r++)
2948     if (r->p && !r->w2 && (r->d == 0 || r->d == -1))
2949       queue_push(&solv->ruleassertions, i);
2950
2951   /* disable update rules that conflict with our job */
2952   solver_disablepolicyrules(solv);
2953
2954   /* make decisions based on job/update assertions */
2955   makeruledecisions(solv);
2956   POOL_DEBUG(SAT_DEBUG_SOLVER, "problems so far: %d\n", solv->problems.count);
2957
2958   /*
2959    * ********************************************
2960    * solve!
2961    * ********************************************
2962    */
2963
2964   now = sat_timems(0);
2965   solver_run_sat(solv, 1, solv->dontinstallrecommended ? 0 : 1);
2966   POOL_DEBUG(SAT_DEBUG_STATS, "solver took %d ms\n", sat_timems(now));
2967
2968   /*
2969    * calculate recommended/suggested packages
2970    */
2971   findrecommendedsuggested(solv);
2972
2973   /*
2974    * prepare solution queue if there were problems
2975    */
2976   solver_prepare_solutions(solv);
2977
2978   /*
2979    * finally prepare transaction info
2980    */
2981   transaction_calculate(&solv->trans, &solv->decisionq, &solv->noobsoletes);
2982
2983   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);
2984   POOL_DEBUG(SAT_DEBUG_STATS, "solver_solve took %d ms\n", sat_timems(solve_start));
2985 }
2986
2987 /***********************************************************************/
2988 /* disk usage computations */
2989
2990 /*-------------------------------------------------------------------
2991  *
2992  * calculate DU changes
2993  */
2994
2995 void
2996 solver_calc_duchanges(Solver *solv, DUChanges *mps, int nmps)
2997 {
2998   Map installedmap;
2999
3000   solver_create_state_maps(solv, &installedmap, 0);
3001   pool_calc_duchanges(solv->pool, &installedmap, mps, nmps);
3002   map_free(&installedmap);
3003 }
3004
3005
3006 /*-------------------------------------------------------------------
3007  *
3008  * calculate changes in install size
3009  */
3010
3011 int
3012 solver_calc_installsizechange(Solver *solv)
3013 {
3014   Map installedmap;
3015   int change;
3016
3017   solver_create_state_maps(solv, &installedmap, 0);
3018   change = pool_calc_installsizechange(solv->pool, &installedmap);
3019   map_free(&installedmap);
3020   return change;
3021 }
3022
3023 void
3024 solver_trivial_installable(Solver *solv, Queue *pkgs, Queue *res)
3025 {
3026   Map installedmap;
3027   solver_create_state_maps(solv, &installedmap, 0);
3028   pool_trivial_installable_noobsoletesmap(solv->pool, &installedmap, pkgs, res, solv->noobsoletes.size ? &solv->noobsoletes : 0);
3029   map_free(&installedmap);
3030 }
3031