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 "solver_private.h"
  22 #include "bitmap.h"
  23 #include "pool.h"
  24 #include "util.h"
  25 #include "policy.h"
  26 #include "poolarch.h"
  27 #include "solverdebug.h"
  28
  29 #define RULES_BLOCK 63
  30
  31 /********************************************************************
  32  *
  33  * dependency check helpers
  34  *
  35  */
  36
  37 /*-------------------------------------------------------------------
  38  * handle split provides
  39  *
  40  * a splitprovides dep looks like
  41  *     namespace:splitprovides(pkg REL_WITH path)
  42  * and is only true if pkg is installed and contains the specified path.
  43  * we also make sure that pkg is selected for an update, otherwise the
  44  * update would always be forced onto the user.
  45  */
  46 int
  47 solver_splitprovides(Solver *solv, Id dep)
  48 {
  49   Pool *pool = solv->pool;
  50   Id p, pp;
  51   Reldep *rd;
  52   Solvable *s;
  53
  54   if (!solv->dosplitprovides || !solv->installed || (!solv->updatemap_all && !solv->updatemap.size))
  55     return 0;
  56   if (!ISRELDEP(dep))
  57     return 0;
  58   rd = GETRELDEP(pool, dep);
  59   if (rd->flags != REL_WITH)
  60     return 0;
  61   FOR_PROVIDES(p, pp, dep)
  62     {
  63       /* here we have packages that provide the correct name and contain the path,
  64        * now do extra filtering */
  65       s = pool->solvables + p;
  66       if (s->repo == solv->installed && s->name == rd->name &&
  67           (solv->updatemap_all || (solv->updatemap.size && MAPTST(&solv->updatemap, p - solv->installed->start))))
  68         return 1;
  69     }
  70   return 0;
  71 }
  72
  73
  74 /*-------------------------------------------------------------------
  75  * solver_dep_installed
  76  */
  77
  78 int
  79 solver_dep_installed(Solver *solv, Id dep)
  80 {
  81 #if 0
  82   Pool *pool = solv->pool;
  83   Id p, pp;
  84
  85   if (ISRELDEP(dep))
  86     {
  87       Reldep *rd = GETRELDEP(pool, dep);
  88       if (rd->flags == REL_AND)
  89         {
  90           if (!solver_dep_installed(solv, rd->name))
  91             return 0;
  92           return solver_dep_installed(solv, rd->evr);
  93         }
  94       if (rd->flags == REL_NAMESPACE && rd->name == NAMESPACE_INSTALLED)
  95         return solver_dep_installed(solv, rd->evr);
  96     }
  97   FOR_PROVIDES(p, pp, dep)
  98     {
  99       if (p == SYSTEMSOLVABLE || (solv->installed && pool->solvables[p].repo == solv->installed))
 100         return 1;
 101     }
 102 #endif
 103   return 0;
 104 }
 105
 106
 107 static Id
 108 autouninstall(Solver *solv, Id *problem)
 109 {
 110   Pool *pool = solv->pool;
 111   int i;
 112   int lastfeature = 0, lastupdate = 0;
 113   Id v;
 114   Id extraflags = -1;
 115
 116   for (i = 0; (v = problem[i]) != 0; i++)
 117     {
 118       if (v < 0)
 119         extraflags &= solv->job.elements[-v - 1];
 120       if (v >= solv->featurerules && v < solv->featurerules_end)
 121         if (v > lastfeature)
 122           lastfeature = v;
 123       if (v >= solv->updaterules && v < solv->updaterules_end)
 124         {
 125           /* check if identical to feature rule */
 126           Id p = solv->rules[v].p;
 127           if (p <= 0)
 128             continue;
 129           Rule *r = solv->rules + solv->featurerules + (p - solv->installed->start);
 130           if (!r->p)
 131             {
 132               /* update rule == feature rule */
 133               if (v > lastfeature)
 134                 lastfeature = v;
 135               continue;
 136             }
 137           if (v > lastupdate)
 138             lastupdate = v;
 139         }
 140     }
 141   if (!lastupdate && !lastfeature)
 142     return 0;
 143   v = lastupdate ? lastupdate : lastfeature;
 144   POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "allowuninstall disabling ");
 145   solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + v);
 146   solver_disableproblem(solv, v);
 147   if (extraflags != -1 && (extraflags & SOLVER_CLEANDEPS) != 0 && solv->cleandepsmap.size)
 148     {
 149       /* add the package to the updatepkgs list, this will automatically turn
 150        * on cleandeps mode */
 151       Id p = solv->rules[v].p;
 152       if (!solv->cleandeps_updatepkgs)
 153         {
 154           solv->cleandeps_updatepkgs = solv_calloc(1, sizeof(Queue));
 155           queue_init(solv->cleandeps_updatepkgs);
 156         }
 157       if (p > 0)
 158         {
 159           int oldupdatepkgscnt = solv->cleandeps_updatepkgs->count;
 160           queue_pushunique(solv->cleandeps_updatepkgs, p);
 161           if (solv->cleandeps_updatepkgs->count != oldupdatepkgscnt)
 162             solver_disablepolicyrules(solv);
 163         }
 164     }
 165   return v;
 166 }
 167
 168 /************************************************************************/
 169
 170 /*
 171  * enable/disable learnt rules
 172  *
 173  * we have enabled or disabled some of our rules. We now reenable all
 174  * of our learnt rules except the ones that were learnt from rules that
 175  * are now disabled.
 176  */
 177 static void
 178 enabledisablelearntrules(Solver *solv)
 179 {
 180   Pool *pool = solv->pool;
 181   Rule *r;
 182   Id why, *whyp;
 183   int i;
 184
 185   POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "enabledisablelearntrules called\n");
 186   for (i = solv->learntrules, r = solv->rules + i; i < solv->nrules; i++, r++)
 187     {
 188       whyp = solv->learnt_pool.elements + solv->learnt_why.elements[i - solv->learntrules];
 189       while ((why = *whyp++) != 0)
 190         {
 191           assert(why > 0 && why < i);
 192           if (solv->rules[why].d < 0)
 193             break;
 194         }
 195       /* why != 0: we found a disabled rule, disable the learnt rule */
 196       if (why && r->d >= 0)
 197         {
 198           IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
 199             {
 200               POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "disabling ");
 201               solver_printruleclass(solv, SOLV_DEBUG_SOLUTIONS, r);
 202             }
 203           solver_disablerule(solv, r);
 204         }
 205       else if (!why && r->d < 0)
 206         {
 207           IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
 208             {
 209               POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "re-enabling ");
 210               solver_printruleclass(solv, SOLV_DEBUG_SOLUTIONS, r);
 211             }
 212           solver_enablerule(solv, r);
 213         }
 214     }
 215 }
 216
 217
 218 /*
 219  * make assertion rules into decisions
 220  *
 221  * Go through rules and add direct assertions to the decisionqueue.
 222  * If we find a conflict, disable rules and add them to problem queue.
 223  */
 224
 225 static void
 226 makeruledecisions(Solver *solv)
 227 {
 228   Pool *pool = solv->pool;
 229   int i, ri, ii;
 230   Rule *r, *rr;
 231   Id v, vv;
 232   int decisionstart;
 233   int record_proof = 1;
 234   int oldproblemcount;
 235   int havedisabled = 0;
 236
 237   /* The system solvable is always installed first */
 238   assert(solv->decisionq.count == 0);
 239   queue_push(&solv->decisionq, SYSTEMSOLVABLE);
 240   queue_push(&solv->decisionq_why, 0);
 241   solv->decisionmap[SYSTEMSOLVABLE] = 1;        /* installed at level '1' */
 242
 243   decisionstart = solv->decisionq.count;
 244   for (;;)
 245     {
 246       /* if we needed to re-run, back up decisions to decisionstart */
 247       while (solv->decisionq.count > decisionstart)
 248         {
 249           v = solv->decisionq.elements[--solv->decisionq.count];
 250           --solv->decisionq_why.count;
 251           vv = v > 0 ? v : -v;
 252           solv->decisionmap[vv] = 0;
 253         }
 254
 255       /* note that the ruleassertions queue is ordered */
 256       for (ii = 0; ii < solv->ruleassertions.count; ii++)
 257         {
 258           ri = solv->ruleassertions.elements[ii];
 259           r = solv->rules + ri;
 260
 261           if (havedisabled && ri >= solv->learntrules)
 262             {
 263               /* just started with learnt rule assertions. If we have disabled
 264                * some rules, adapt the learnt rule status */
 265               enabledisablelearntrules(solv);
 266               havedisabled = 0;
 267             }
 268
 269           if (r->d < 0 || !r->p || r->w2)       /* disabled, dummy or no assertion */
 270             continue;
 271
 272           /* do weak rules in phase 2 */
 273           if (ri < solv->learntrules && MAPTST(&solv->weakrulemap, ri))
 274             continue;
 275
 276           v = r->p;
 277           vv = v > 0 ? v : -v;
 278
 279           if (!solv->decisionmap[vv])          /* if not yet decided */
 280             {
 281               queue_push(&solv->decisionq, v);
 282               queue_push(&solv->decisionq_why, r - solv->rules);
 283               solv->decisionmap[vv] = v > 0 ? 1 : -1;
 284               IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 285                 {
 286                   Solvable *s = solv->pool->solvables + vv;
 287                   if (v < 0)
 288                     POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "conflicting %s (assertion)\n", pool_solvable2str(solv->pool, s));
 289                   else
 290                     POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "installing  %s (assertion)\n", pool_solvable2str(solv->pool, s));
 291                 }
 292               continue;
 293             }
 294
 295           /* check against previous decision: is there a conflict? */
 296           if (v > 0 && solv->decisionmap[vv] > 0)    /* ok to install */
 297             continue;
 298           if (v < 0 && solv->decisionmap[vv] < 0)    /* ok to remove */
 299             continue;
 300
 301           /*
 302            * found a conflict!
 303            *
 304            * The rule (r) we're currently processing says something
 305            * different (v = r->p) than a previous decision (decisionmap[abs(v)])
 306            * on this literal
 307            */
 308
 309           if (ri >= solv->learntrules)
 310             {
 311               /* conflict with a learnt rule */
 312               /* can happen when packages cannot be installed for multiple reasons. */
 313               /* we disable the learnt rule in this case */
 314               /* (XXX: we should really call analyze_unsolvable_rule here!) */
 315               solver_disablerule(solv, r);
 316               continue;
 317             }
 318
 319           /*
 320            * find the decision which is the "opposite" of the rule
 321            */
 322           for (i = 0; i < solv->decisionq.count; i++)
 323             if (solv->decisionq.elements[i] == -v)
 324               break;
 325           assert(i < solv->decisionq.count);         /* assert that we found it */
 326           oldproblemcount = solv->problems.count;
 327
 328           /*
 329            * conflict with system solvable ?
 330            */
 331           if (v == -SYSTEMSOLVABLE)
 332             {
 333               if (record_proof)
 334                 {
 335                   queue_push(&solv->problems, solv->learnt_pool.count);
 336                   queue_push(&solv->learnt_pool, ri);
 337                   queue_push(&solv->learnt_pool, 0);
 338                 }
 339               else
 340                 queue_push(&solv->problems, 0);
 341               POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "conflict with system solvable, disabling rule #%d\n", ri);
 342               if  (ri >= solv->jobrules && ri < solv->jobrules_end)
 343                 v = -(solv->ruletojob.elements[ri - solv->jobrules] + 1);
 344               else
 345                 v = ri;
 346               queue_push(&solv->problems, v);
 347               queue_push(&solv->problems, 0);
 348               if (solv->allowuninstall && v >= solv->featurerules && v < solv->updaterules_end)
 349                 solv->problems.count = oldproblemcount;
 350               solver_disableproblem(solv, v);
 351               havedisabled = 1;
 352               break;    /* start over */
 353             }
 354
 355           assert(solv->decisionq_why.elements[i] > 0);
 356
 357           /*
 358            * conflict with an rpm rule ?
 359            */
 360           if (solv->decisionq_why.elements[i] < solv->rpmrules_end)
 361             {
 362               if (record_proof)
 363                 {
 364                   queue_push(&solv->problems, solv->learnt_pool.count);
 365                   queue_push(&solv->learnt_pool, ri);
 366                   queue_push(&solv->learnt_pool, solv->decisionq_why.elements[i]);
 367                   queue_push(&solv->learnt_pool, 0);
 368                 }
 369               else
 370                 queue_push(&solv->problems, 0);
 371               assert(v > 0 || v == -SYSTEMSOLVABLE);
 372               POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "conflict with rpm rule, disabling rule #%d\n", ri);
 373               if (ri >= solv->jobrules && ri < solv->jobrules_end)
 374                 v = -(solv->ruletojob.elements[ri - solv->jobrules] + 1);
 375               else
 376                 v = ri;
 377               queue_push(&solv->problems, v);
 378               queue_push(&solv->problems, 0);
 379               if (solv->allowuninstall && v >= solv->featurerules && v < solv->updaterules_end)
 380                 solv->problems.count = oldproblemcount;
 381               solver_disableproblem(solv, v);
 382               havedisabled = 1;
 383               break;    /* start over */
 384             }
 385
 386           /*
 387            * conflict with another job or update/feature rule
 388            */
 389
 390           /* record proof */
 391           if (record_proof)
 392             {
 393               queue_push(&solv->problems, solv->learnt_pool.count);
 394               queue_push(&solv->learnt_pool, ri);
 395               queue_push(&solv->learnt_pool, solv->decisionq_why.elements[i]);
 396               queue_push(&solv->learnt_pool, 0);
 397             }
 398           else
 399             queue_push(&solv->problems, 0);
 400
 401           POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "conflicting update/job assertions over literal %d\n", vv);
 402
 403           /*
 404            * push all of our rules (can only be feature or job rules)
 405            * asserting this literal on the problem stack
 406            */
 407           for (i = solv->featurerules, rr = solv->rules + i; i < solv->learntrules; i++, rr++)
 408             {
 409               if (rr->d < 0                          /* disabled */
 410                   || rr->w2)                         /*  or no assertion */
 411                 continue;
 412               if (rr->p != vv                        /* not affecting the literal */
 413                   && rr->p != -vv)
 414                 continue;
 415               if (MAPTST(&solv->weakrulemap, i))     /* weak: silently ignore */
 416                 continue;
 417
 418               POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, " - disabling rule #%d\n", i);
 419               solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + i);
 420
 421               v = i;
 422               if (i >= solv->jobrules && i < solv->jobrules_end)
 423                 v = -(solv->ruletojob.elements[i - solv->jobrules] + 1);
 424               queue_push(&solv->problems, v);
 425             }
 426           queue_push(&solv->problems, 0);
 427
 428           if (solv->allowuninstall && (v = autouninstall(solv, solv->problems.elements + oldproblemcount + 1)) != 0)
 429             solv->problems.count = oldproblemcount;
 430
 431           for (i = oldproblemcount + 1; i < solv->problems.count - 1; i++)
 432             solver_disableproblem(solv, solv->problems.elements[i]);
 433           havedisabled = 1;
 434           break;        /* start over */
 435         }
 436       if (ii < solv->ruleassertions.count)
 437         continue;
 438
 439       /*
 440        * phase 2: now do the weak assertions
 441        */
 442       for (ii = 0; ii < solv->ruleassertions.count; ii++)
 443         {
 444           ri = solv->ruleassertions.elements[ii];
 445           r = solv->rules + ri;
 446           if (r->d < 0 || r->w2)                         /* disabled or no assertion */
 447             continue;
 448           if (ri >= solv->learntrules || !MAPTST(&solv->weakrulemap, ri))       /* skip non-weak */
 449             continue;
 450           v = r->p;
 451           vv = v > 0 ? v : -v;
 452
 453           if (!solv->decisionmap[vv])          /* if not yet decided */
 454             {
 455               queue_push(&solv->decisionq, v);
 456               queue_push(&solv->decisionq_why, r - solv->rules);
 457               solv->decisionmap[vv] = v > 0 ? 1 : -1;
 458               IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 459                 {
 460                   Solvable *s = solv->pool->solvables + vv;
 461                   if (v < 0)
 462                     POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "conflicting %s (weak assertion)\n", pool_solvable2str(solv->pool, s));
 463                   else
 464                     POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "installing  %s (weak assertion)\n", pool_solvable2str(solv->pool, s));
 465                 }
 466               continue;
 467             }
 468           /* check against previous decision: is there a conflict? */
 469           if (v > 0 && solv->decisionmap[vv] > 0)
 470             continue;
 471           if (v < 0 && solv->decisionmap[vv] < 0)
 472             continue;
 473
 474           POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "assertion conflict, but I am weak, disabling ");
 475           solver_printrule(solv, SOLV_DEBUG_UNSOLVABLE, r);
 476
 477           if (ri >= solv->jobrules && ri < solv->jobrules_end)
 478             v = -(solv->ruletojob.elements[ri - solv->jobrules] + 1);
 479           else
 480             v = ri;
 481           solver_disableproblem(solv, v);
 482           if (v < 0)
 483             solver_reenablepolicyrules(solv, -v);
 484           havedisabled = 1;
 485           break;        /* start over */
 486         }
 487       if (ii == solv->ruleassertions.count)
 488         break;  /* finished! */
 489     }
 490 }
 491
 492
 493 /********************************************************************/
 494 /* watches */
 495
 496
 497 /*-------------------------------------------------------------------
 498  * makewatches
 499  *
 500  * initial setup for all watches
 501  */
 502
 503 static void
 504 makewatches(Solver *solv)
 505 {
 506   Rule *r;
 507   int i;
 508   int nsolvables = solv->pool->nsolvables;
 509
 510   solv_free(solv->watches);
 511                                        /* lower half for removals, upper half for installs */
 512   solv->watches = solv_calloc(2 * nsolvables, sizeof(Id));
 513 #if 1
 514   /* do it reverse so rpm rules get triggered first (XXX: obsolete?) */
 515   for (i = 1, r = solv->rules + solv->nrules - 1; i < solv->nrules; i++, r--)
 516 #else
 517   for (i = 1, r = solv->rules + 1; i < solv->nrules; i++, r++)
 518 #endif
 519     {
 520       if (!r->w2)               /* assertions do not need watches */
 521         continue;
 522
 523       /* see addwatches_rule(solv, r) */
 524       r->n1 = solv->watches[nsolvables + r->w1];
 525       solv->watches[nsolvables + r->w1] = r - solv->rules;
 526
 527       r->n2 = solv->watches[nsolvables + r->w2];
 528       solv->watches[nsolvables + r->w2] = r - solv->rules;
 529     }
 530 }
 531
 532
 533 /*-------------------------------------------------------------------
 534  *
 535  * add watches (for a new learned rule)
 536  * sets up watches for a single rule
 537  *
 538  * see also makewatches() above.
 539  */
 540
 541 static inline void
 542 addwatches_rule(Solver *solv, Rule *r)
 543 {
 544   int nsolvables = solv->pool->nsolvables;
 545
 546   r->n1 = solv->watches[nsolvables + r->w1];
 547   solv->watches[nsolvables + r->w1] = r - solv->rules;
 548
 549   r->n2 = solv->watches[nsolvables + r->w2];
 550   solv->watches[nsolvables + r->w2] = r - solv->rules;
 551 }
 552
 553
 554 /********************************************************************/
 555 /*
 556  * rule propagation
 557  */
 558
 559
 560 /* shortcuts to check if a literal (positive or negative) assignment
 561  * evaluates to 'true' or 'false'
 562  */
 563 #define DECISIONMAP_TRUE(p) ((p) > 0 ? (decisionmap[p] > 0) : (decisionmap[-p] < 0))
 564 #define DECISIONMAP_FALSE(p) ((p) > 0 ? (decisionmap[p] < 0) : (decisionmap[-p] > 0))
 565 #define DECISIONMAP_UNDEF(p) (decisionmap[(p) > 0 ? (p) : -(p)] == 0)
 566
 567 /*-------------------------------------------------------------------
 568  *
 569  * propagate
 570  *
 571  * make decision and propagate to all rules
 572  *
 573  * Evaluate each term affected by the decision (linked through watches).
 574  * If we find unit rules we make new decisions based on them.
 575  *
 576  * return : 0 = everything is OK
 577  *          rule = conflict found in this rule
 578  */
 579
 580 static Rule *
 581 propagate(Solver *solv, int level)
 582 {
 583   Pool *pool = solv->pool;
 584   Id *rp, *next_rp;           /* rule pointer, next rule pointer in linked list */
 585   Rule *r;                    /* rule */
 586   Id p, pkg, other_watch;
 587   Id *dp;
 588   Id *decisionmap = solv->decisionmap;
 589
 590   Id *watches = solv->watches + pool->nsolvables;   /* place ptr in middle */
 591
 592   POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "----- propagate -----\n");
 593
 594   /* foreach non-propagated decision */
 595   while (solv->propagate_index < solv->decisionq.count)
 596     {
 597         /*
 598          * 'pkg' was just decided
 599          * negate because our watches trigger if literal goes FALSE
 600          */
 601       pkg = -solv->decisionq.elements[solv->propagate_index++];
 602
 603       IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 604         {
 605           POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "propagate for decision %d level %d\n", -pkg, level);
 606           solver_printruleelement(solv, SOLV_DEBUG_PROPAGATE, 0, -pkg);
 607         }
 608
 609       /* foreach rule where 'pkg' is now FALSE */
 610       for (rp = watches + pkg; *rp; rp = next_rp)
 611         {
 612           r = solv->rules + *rp;
 613           if (r->d < 0)
 614             {
 615               /* rule is disabled, goto next */
 616               if (pkg == r->w1)
 617                 next_rp = &r->n1;
 618               else
 619                 next_rp = &r->n2;
 620               continue;
 621             }
 622
 623           IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 624             {
 625               POOL_DEBUG(SOLV_DEBUG_PROPAGATE,"  watch triggered ");
 626               solver_printrule(solv, SOLV_DEBUG_PROPAGATE, r);
 627             }
 628
 629             /* 'pkg' was just decided (was set to FALSE)
 630              *
 631              *  now find other literal watch, check clause
 632              *   and advance on linked list
 633              */
 634           if (pkg == r->w1)
 635             {
 636               other_watch = r->w2;
 637               next_rp = &r->n1;
 638             }
 639           else
 640             {
 641               other_watch = r->w1;
 642               next_rp = &r->n2;
 643             }
 644
 645             /*
 646              * This term is already true (through the other literal)
 647              * so we have nothing to do
 648              */
 649           if (DECISIONMAP_TRUE(other_watch))
 650             continue;
 651
 652             /*
 653              * The other literal is FALSE or UNDEF
 654              *
 655              */
 656
 657           if (r->d)
 658             {
 659               /* Not a binary clause, try to move our watch.
 660                *
 661                * Go over all literals and find one that is
 662                *   not other_watch
 663                *   and not FALSE
 664                *
 665                * (TRUE is also ok, in that case the rule is fulfilled)
 666                */
 667               if (r->p                                /* we have a 'p' */
 668                   && r->p != other_watch              /* which is not watched */
 669                   && !DECISIONMAP_FALSE(r->p))        /* and not FALSE */
 670                 {
 671                   p = r->p;
 672                 }
 673               else                                    /* go find a 'd' to make 'true' */
 674                 {
 675                   /* foreach p in 'd'
 676                      we just iterate sequentially, doing it in another order just changes the order of decisions, not the decisions itself
 677                    */
 678                   for (dp = pool->whatprovidesdata + r->d; (p = *dp++) != 0;)
 679                     {
 680                       if (p != other_watch              /* which is not watched */
 681                           && !DECISIONMAP_FALSE(p))     /* and not FALSE */
 682                         break;
 683                     }
 684                 }
 685
 686               if (p)
 687                 {
 688                   /*
 689                    * if we found some p that is UNDEF or TRUE, move
 690                    * watch to it
 691                    */
 692                   IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 693                     {
 694                       if (p > 0)
 695                         POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "    -> move w%d to %s\n", (pkg == r->w1 ? 1 : 2), pool_solvid2str(pool, p));
 696                       else
 697                         POOL_DEBUG(SOLV_DEBUG_PROPAGATE,"    -> move w%d to !%s\n", (pkg == r->w1 ? 1 : 2), pool_solvid2str(pool, -p));
 698                     }
 699
 700                   *rp = *next_rp;
 701                   next_rp = rp;
 702
 703                   if (pkg == r->w1)
 704                     {
 705                       r->w1 = p;
 706                       r->n1 = watches[p];
 707                     }
 708                   else
 709                     {
 710                       r->w2 = p;
 711                       r->n2 = watches[p];
 712                     }
 713                   watches[p] = r - solv->rules;
 714                   continue;
 715                 }
 716               /* search failed, thus all unwatched literals are FALSE */
 717
 718             } /* not binary */
 719
 720           /*
 721            * unit clause found, set literal other_watch to TRUE
 722            */
 723
 724           if (DECISIONMAP_FALSE(other_watch))      /* check if literal is FALSE */
 725             return r;                              /* eek, a conflict! */
 726
 727           IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 728             {
 729               POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "   unit ");
 730               solver_printrule(solv, SOLV_DEBUG_PROPAGATE, r);
 731             }
 732
 733           if (other_watch > 0)
 734             decisionmap[other_watch] = level;    /* install! */
 735           else
 736             decisionmap[-other_watch] = -level;  /* remove! */
 737
 738           queue_push(&solv->decisionq, other_watch);
 739           queue_push(&solv->decisionq_why, r - solv->rules);
 740
 741           IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
 742             {
 743               if (other_watch > 0)
 744                 POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "    -> decided to install %s\n", pool_solvid2str(pool, other_watch));
 745               else
 746                 POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "    -> decided to conflict %s\n", pool_solvid2str(pool, -other_watch));
 747             }
 748
 749         } /* foreach rule involving 'pkg' */
 750
 751     } /* while we have non-decided decisions */
 752
 753   POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "----- propagate end-----\n");
 754
 755   return 0;     /* all is well */
 756 }
 757
 758
 759 /********************************************************************/
 760 /* Analysis */
 761
 762 /*-------------------------------------------------------------------
 763  *
 764  * analyze
 765  *   and learn
 766  */
 767
 768 static int
 769 analyze(Solver *solv, int level, Rule *c, int *pr, int *dr, int *whyp)
 770 {
 771   Pool *pool = solv->pool;
 772   Queue r;
 773   Id r_buf[4];
 774   int rlevel = 1;
 775   Map seen;             /* global? */
 776   Id d, v, vv, *dp, why;
 777   int l, i, idx;
 778   int num = 0, l1num = 0;
 779   int learnt_why = solv->learnt_pool.count;
 780   Id *decisionmap = solv->decisionmap;
 781
 782   queue_init_buffer(&r, r_buf, sizeof(r_buf)/sizeof(*r_buf));
 783
 784   POOL_DEBUG(SOLV_DEBUG_ANALYZE, "ANALYZE at %d ----------------------\n", level);
 785   map_init(&seen, pool->nsolvables);
 786   idx = solv->decisionq.count;
 787   for (;;)
 788     {
 789       IF_POOLDEBUG (SOLV_DEBUG_ANALYZE)
 790         solver_printruleclass(solv, SOLV_DEBUG_ANALYZE, c);
 791       queue_push(&solv->learnt_pool, c - solv->rules);
 792       d = c->d < 0 ? -c->d - 1 : c->d;
 793       dp = d ? pool->whatprovidesdata + d : 0;
 794       /* go through all literals of the rule */
 795       for (i = -1; ; i++)
 796         {
 797           if (i == -1)
 798             v = c->p;
 799           else if (d == 0)
 800             v = i ? 0 : c->w2;
 801           else
 802             v = *dp++;
 803           if (v == 0)
 804             break;
 805
 806           if (DECISIONMAP_TRUE(v))      /* the one true literal */
 807             continue;
 808           vv = v > 0 ? v : -v;
 809           if (MAPTST(&seen, vv))
 810             continue;
 811           l = solv->decisionmap[vv];
 812           if (l < 0)
 813             l = -l;
 814           MAPSET(&seen, vv);            /* mark that we also need to look at this literal */
 815           if (l == 1)
 816             l1num++;                    /* need to do this one in level1 pass */
 817           else if (l == level)
 818             num++;                      /* need to do this one as well */
 819           else
 820             {
 821               queue_push(&r, v);        /* not level1 or conflict level, add to new rule */
 822               if (l > rlevel)
 823                 rlevel = l;
 824             }
 825         }
 826 l1retry:
 827       if (!num && !--l1num)
 828         break;  /* all level 1 literals done */
 829
 830       /* find the next literal to investigate */
 831       /* (as num + l1num > 0, we know that we'll always find one) */
 832       for (;;)
 833         {
 834           assert(idx > 0);
 835           v = solv->decisionq.elements[--idx];
 836           vv = v > 0 ? v : -v;
 837           if (MAPTST(&seen, vv))
 838             break;
 839         }
 840       MAPCLR(&seen, vv);
 841
 842       if (num && --num == 0)
 843         {
 844           *pr = -v;     /* so that v doesn't get lost */
 845           if (!l1num)
 846             break;
 847           POOL_DEBUG(SOLV_DEBUG_ANALYZE, "got %d involved level 1 decisions\n", l1num);
 848           /* clear non-l1 bits from seen map */
 849           for (i = 0; i < r.count; i++)
 850             {
 851               v = r.elements[i];
 852               MAPCLR(&seen, v > 0 ? v : -v);
 853             }
 854           /* only level 1 marks left in seen map */
 855           l1num++;      /* as l1retry decrements it */
 856           goto l1retry;
 857         }
 858
 859       why = solv->decisionq_why.elements[idx];
 860       if (why <= 0)     /* just in case, maybe for SYSTEMSOLVABLE */
 861         goto l1retry;
 862       c = solv->rules + why;
 863     }
 864   map_free(&seen);
 865
 866   if (r.count == 0)
 867     *dr = 0;
 868   else if (r.count == 1 && r.elements[0] < 0)
 869     *dr = r.elements[0];
 870   else
 871     *dr = pool_queuetowhatprovides(pool, &r);
 872   IF_POOLDEBUG (SOLV_DEBUG_ANALYZE)
 873     {
 874       POOL_DEBUG(SOLV_DEBUG_ANALYZE, "learned rule for level %d (am %d)\n", rlevel, level);
 875       solver_printruleelement(solv, SOLV_DEBUG_ANALYZE, 0, *pr);
 876       for (i = 0; i < r.count; i++)
 877         solver_printruleelement(solv, SOLV_DEBUG_ANALYZE, 0, r.elements[i]);
 878     }
 879   /* push end marker on learnt reasons stack */
 880   queue_push(&solv->learnt_pool, 0);
 881   if (whyp)
 882     *whyp = learnt_why;
 883   queue_free(&r);
 884   solv->stats_learned++;
 885   return rlevel;
 886 }
 887
 888
 889 /*-------------------------------------------------------------------
 890  *
 891  * solver_reset
 892  *
 893  * reset all solver decisions
 894  * called after rules have been enabled/disabled
 895  */
 896
 897 void
 898 solver_reset(Solver *solv)
 899 {
 900   Pool *pool = solv->pool;
 901   int i;
 902   Id v;
 903
 904   /* rewind all decisions */
 905   for (i = solv->decisionq.count - 1; i >= 0; i--)
 906     {
 907       v = solv->decisionq.elements[i];
 908       solv->decisionmap[v > 0 ? v : -v] = 0;
 909     }
 910   solv->decisionq_why.count = 0;
 911   solv->decisionq.count = 0;
 912   solv->recommends_index = -1;
 913   solv->propagate_index = 0;
 914   solv->branches.count = 0;
 915
 916   /* adapt learnt rule status to new set of enabled/disabled rules */
 917   enabledisablelearntrules(solv);
 918
 919   /* redo all assertion rule decisions */
 920   makeruledecisions(solv);
 921   POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "decisions so far: %d\n", solv->decisionq.count);
 922 }
 923
 924
 925 /*-------------------------------------------------------------------
 926  *
 927  * analyze_unsolvable_rule
 928  *
 929  * recursion helper used by analyze_unsolvable
 930  */
 931
 932 static void
 933 analyze_unsolvable_rule(Solver *solv, Rule *r, Id *lastweakp, Map *rseen)
 934 {
 935   Pool *pool = solv->pool;
 936   int i;
 937   Id why = r - solv->rules;
 938
 939   IF_POOLDEBUG (SOLV_DEBUG_UNSOLVABLE)
 940     solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, r);
 941   if (solv->learntrules && why >= solv->learntrules)
 942     {
 943       if (MAPTST(rseen, why - solv->learntrules))
 944         return;
 945       MAPSET(rseen, why - solv->learntrules);
 946       for (i = solv->learnt_why.elements[why - solv->learntrules]; solv->learnt_pool.elements[i]; i++)
 947         if (solv->learnt_pool.elements[i] > 0)
 948           analyze_unsolvable_rule(solv, solv->rules + solv->learnt_pool.elements[i], lastweakp, rseen);
 949       return;
 950     }
 951   if (MAPTST(&solv->weakrulemap, why))
 952     if (!*lastweakp || why > *lastweakp)
 953       *lastweakp = why;
 954   /* do not add rpm rules to problem */
 955   if (why < solv->rpmrules_end)
 956     return;
 957   /* turn rule into problem */
 958   if (why >= solv->jobrules && why < solv->jobrules_end)
 959     why = -(solv->ruletojob.elements[why - solv->jobrules] + 1);
 960   /* normalize dup/infarch rules */
 961   if (why > solv->infarchrules && why < solv->infarchrules_end)
 962     {
 963       Id name = pool->solvables[-solv->rules[why].p].name;
 964       while (why > solv->infarchrules && pool->solvables[-solv->rules[why - 1].p].name == name)
 965         why--;
 966     }
 967   if (why > solv->duprules && why < solv->duprules_end)
 968     {
 969       Id name = pool->solvables[-solv->rules[why].p].name;
 970       while (why > solv->duprules && pool->solvables[-solv->rules[why - 1].p].name == name)
 971         why--;
 972     }
 973
 974   /* return if problem already countains our rule */
 975   if (solv->problems.count)
 976     {
 977       for (i = solv->problems.count - 1; i >= 0; i--)
 978         if (solv->problems.elements[i] == 0)    /* end of last problem reached? */
 979           break;
 980         else if (solv->problems.elements[i] == why)
 981           return;
 982     }
 983   queue_push(&solv->problems, why);
 984 }
 985
 986
 987 /*-------------------------------------------------------------------
 988  *
 989  * analyze_unsolvable
 990  *
 991  * We know that the problem is not solvable. Record all involved
 992  * rules (i.e. the "proof") into solv->learnt_pool.
 993  * Record the learnt pool index and all non-rpm rules into
 994  * solv->problems. (Our solutions to fix the problems are to
 995  * disable those rules.)
 996  *
 997  * If the proof contains at least one weak rule, we disable the
 998  * last of them.
 999  *
1000  * Otherwise we return 0 if disablerules is not set or disable
1001  * _all_ of the problem rules and return 1.
1002  *
1003  * return: 1 - disabled some rules, try again
1004  *         0 - hopeless
1005  */
1006
1007 static int
1008 analyze_unsolvable(Solver *solv, Rule *cr, int disablerules)
1009 {
1010   Pool *pool = solv->pool;
1011   Rule *r;
1012   Map seen;             /* global to speed things up? */
1013   Map rseen;
1014   Id d, v, vv, *dp, why;
1015   int l, i, idx;
1016   Id *decisionmap = solv->decisionmap;
1017   int oldproblemcount;
1018   int oldlearntpoolcount;
1019   Id lastweak;
1020   int record_proof = 1;
1021
1022   POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "ANALYZE UNSOLVABLE ----------------------\n");
1023   solv->stats_unsolvable++;
1024   oldproblemcount = solv->problems.count;
1025   oldlearntpoolcount = solv->learnt_pool.count;
1026
1027   /* make room for proof index */
1028   /* must update it later, as analyze_unsolvable_rule would confuse
1029    * it with a rule index if we put the real value in already */
1030   queue_push(&solv->problems, 0);
1031
1032   r = cr;
1033   map_init(&seen, pool->nsolvables);
1034   map_init(&rseen, solv->learntrules ? solv->nrules - solv->learntrules : 0);
1035   if (record_proof)
1036     queue_push(&solv->learnt_pool, r - solv->rules);
1037   lastweak = 0;
1038   analyze_unsolvable_rule(solv, r, &lastweak, &rseen);
1039   d = r->d < 0 ? -r->d - 1 : r->d;
1040   dp = d ? pool->whatprovidesdata + d : 0;
1041   for (i = -1; ; i++)
1042     {
1043       if (i == -1)
1044         v = r->p;
1045       else if (d == 0)
1046         v = i ? 0 : r->w2;
1047       else
1048         v = *dp++;
1049       if (v == 0)
1050         break;
1051       if (DECISIONMAP_TRUE(v))  /* the one true literal */
1052           continue;
1053       vv = v > 0 ? v : -v;
1054       l = solv->decisionmap[vv];
1055       if (l < 0)
1056         l = -l;
1057       MAPSET(&seen, vv);
1058     }
1059   idx = solv->decisionq.count;
1060   while (idx > 0)
1061     {
1062       v = solv->decisionq.elements[--idx];
1063       vv = v > 0 ? v : -v;
1064       if (!MAPTST(&seen, vv))
1065         continue;
1066       why = solv->decisionq_why.elements[idx];
1067       assert(why > 0);
1068       if (record_proof)
1069         queue_push(&solv->learnt_pool, why);
1070       r = solv->rules + why;
1071       analyze_unsolvable_rule(solv, r, &lastweak, &rseen);
1072       d = r->d < 0 ? -r->d - 1 : r->d;
1073       dp = d ? pool->whatprovidesdata + d : 0;
1074       for (i = -1; ; i++)
1075         {
1076           if (i == -1)
1077             v = r->p;
1078           else if (d == 0)
1079             v = i ? 0 : r->w2;
1080           else
1081             v = *dp++;
1082           if (v == 0)
1083             break;
1084           if (DECISIONMAP_TRUE(v))      /* the one true literal */
1085               continue;
1086           vv = v > 0 ? v : -v;
1087           l = solv->decisionmap[vv];
1088           if (l < 0)
1089             l = -l;
1090           MAPSET(&seen, vv);
1091         }
1092     }
1093   map_free(&seen);
1094   map_free(&rseen);
1095   queue_push(&solv->problems, 0);       /* mark end of this problem */
1096
1097   if (lastweak)
1098     {
1099       /* disable last weak rule */
1100       solv->problems.count = oldproblemcount;
1101       solv->learnt_pool.count = oldlearntpoolcount;
1102       if (lastweak >= solv->jobrules && lastweak < solv->jobrules_end)
1103         v = -(solv->ruletojob.elements[lastweak - solv->jobrules] + 1);
1104       else
1105         v = lastweak;
1106       POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "disabling ");
1107       solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + lastweak);
1108       if (lastweak >= solv->choicerules && lastweak < solv->choicerules_end)
1109         solver_disablechoicerules(solv, solv->rules + lastweak);
1110       solver_disableproblem(solv, v);
1111       if (v < 0)
1112         solver_reenablepolicyrules(solv, -v);
1113       solver_reset(solv);
1114       return 1;
1115     }
1116
1117   if (solv->allowuninstall && (v = autouninstall(solv, solv->problems.elements + oldproblemcount + 1)) != 0)
1118     {
1119       solv->problems.count = oldproblemcount;
1120       solv->learnt_pool.count = oldlearntpoolcount;
1121       solver_reset(solv);
1122       return 1;
1123     }
1124
1125   /* finish proof */
1126   if (record_proof)
1127     {
1128       queue_push(&solv->learnt_pool, 0);
1129       solv->problems.elements[oldproblemcount] = oldlearntpoolcount;
1130     }
1131
1132   /* + 2: index + trailing zero */
1133   if (disablerules && oldproblemcount + 2 < solv->problems.count)
1134     {
1135       for (i = oldproblemcount + 1; i < solv->problems.count - 1; i++)
1136         solver_disableproblem(solv, solv->problems.elements[i]);
1137       /* XXX: might want to enable all weak rules again */
1138       solver_reset(solv);
1139       return 1;
1140     }
1141   POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "UNSOLVABLE\n");
1142   return 0;
1143 }
1144
1145
1146 /********************************************************************/
1147 /* Decision revert */
1148
1149 /*-------------------------------------------------------------------
1150  *
1151  * revert
1152  * revert decisionq to a level
1153  */
1154
1155 static void
1156 revert(Solver *solv, int level)
1157 {
1158   Pool *pool = solv->pool;
1159   Id v, vv;
1160   while (solv->decisionq.count)
1161     {
1162       v = solv->decisionq.elements[solv->decisionq.count - 1];
1163       vv = v > 0 ? v : -v;
1164       if (solv->decisionmap[vv] <= level && solv->decisionmap[vv] >= -level)
1165         break;
1166       POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "reverting decision %d at %d\n", v, solv->decisionmap[vv]);
1167       solv->decisionmap[vv] = 0;
1168       solv->decisionq.count--;
1169       solv->decisionq_why.count--;
1170       solv->propagate_index = solv->decisionq.count;
1171     }
1172   while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] <= -level)
1173     {
1174       solv->branches.count--;
1175       while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] >= 0)
1176         solv->branches.count--;
1177     }
1178   solv->recommends_index = -1;
1179 }
1180
1181
1182 /*-------------------------------------------------------------------
1183  *
1184  * watch2onhighest - put watch2 on literal with highest level
1185  */
1186
1187 static inline void
1188 watch2onhighest(Solver *solv, Rule *r)
1189 {
1190   int l, wl = 0;
1191   Id d, v, *dp;
1192
1193   d = r->d < 0 ? -r->d - 1 : r->d;
1194   if (!d)
1195     return;     /* binary rule, both watches are set */
1196   dp = solv->pool->whatprovidesdata + d;
1197   while ((v = *dp++) != 0)
1198     {
1199       l = solv->decisionmap[v < 0 ? -v : v];
1200       if (l < 0)
1201         l = -l;
1202       if (l > wl)
1203         {
1204           r->w2 = dp[-1];
1205           wl = l;
1206         }
1207     }
1208 }
1209
1210
1211 /*-------------------------------------------------------------------
1212  *
1213  * setpropagatelearn
1214  *
1215  * add free decision (solvable to install) to decisionq
1216  * increase level and propagate decision
1217  * return if no conflict.
1218  *
1219  * in conflict case, analyze conflict rule, add resulting
1220  * rule to learnt rule set, make decision from learnt
1221  * rule (always unit) and re-propagate.
1222  *
1223  * returns the new solver level or 0 if unsolvable
1224  *
1225  */
1226
1227 static int
1228 setpropagatelearn(Solver *solv, int level, Id decision, int disablerules, Id ruleid)
1229 {
1230   Pool *pool = solv->pool;
1231   Rule *r;
1232   Id p = 0, d = 0;
1233   int l, why;
1234
1235   assert(ruleid >= 0);
1236   if (decision)
1237     {
1238       level++;
1239       if (decision > 0)
1240         solv->decisionmap[decision] = level;
1241       else
1242         solv->decisionmap[-decision] = -level;
1243       queue_push(&solv->decisionq, decision);
1244       queue_push(&solv->decisionq_why, -ruleid);        /* <= 0 -> free decision */
1245     }
1246   for (;;)
1247     {
1248       r = propagate(solv, level);
1249       if (!r)
1250         break;
1251       if (level == 1)
1252         return analyze_unsolvable(solv, r, disablerules);
1253       POOL_DEBUG(SOLV_DEBUG_ANALYZE, "conflict with rule #%d\n", (int)(r - solv->rules));
1254       l = analyze(solv, level, r, &p, &d, &why);        /* learnt rule in p and d */
1255       assert(l > 0 && l < level);
1256       POOL_DEBUG(SOLV_DEBUG_ANALYZE, "reverting decisions (level %d -> %d)\n", level, l);
1257       level = l;
1258       revert(solv, level);
1259       r = solver_addrule(solv, p, d);
1260       assert(r);
1261       assert(solv->learnt_why.count == (r - solv->rules) - solv->learntrules);
1262       queue_push(&solv->learnt_why, why);
1263       if (d)
1264         {
1265           /* at least 2 literals, needs watches */
1266           watch2onhighest(solv, r);
1267           addwatches_rule(solv, r);
1268         }
1269       else
1270         {
1271           /* learnt rule is an assertion */
1272           queue_push(&solv->ruleassertions, r - solv->rules);
1273         }
1274       /* the new rule is unit by design */
1275       solv->decisionmap[p > 0 ? p : -p] = p > 0 ? level : -level;
1276       queue_push(&solv->decisionq, p);
1277       queue_push(&solv->decisionq_why, r - solv->rules);
1278       IF_POOLDEBUG (SOLV_DEBUG_ANALYZE)
1279         {
1280           POOL_DEBUG(SOLV_DEBUG_ANALYZE, "decision: ");
1281           solver_printruleelement(solv, SOLV_DEBUG_ANALYZE, 0, p);
1282           POOL_DEBUG(SOLV_DEBUG_ANALYZE, "new rule: ");
1283           solver_printrule(solv, SOLV_DEBUG_ANALYZE, r);
1284         }
1285     }
1286   return level;
1287 }
1288
1289
1290 /*-------------------------------------------------------------------
1291  *
1292  * select and install
1293  *
1294  * install best package from the queue. We add an extra package, inst, if
1295  * provided. See comment in weak install section.
1296  *
1297  * returns the new solver level or 0 if unsolvable
1298  *
1299  */
1300
1301 static int
1302 selectandinstall(Solver *solv, int level, Queue *dq, int disablerules, Id ruleid)
1303 {
1304   Pool *pool = solv->pool;
1305   Id p;
1306   int i;
1307
1308   if (dq->count > 1)
1309     policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
1310   if (dq->count > 1)
1311     {
1312       /* XXX: didn't we already do that? */
1313       /* XXX: shouldn't we prefer installed packages? */
1314       /* XXX: move to policy.c? */
1315       /* choose the supplemented one */
1316       for (i = 0; i < dq->count; i++)
1317         if (solver_is_supplementing(solv, pool->solvables + dq->elements[i]))
1318           {
1319             dq->elements[0] = dq->elements[i];
1320             dq->count = 1;
1321             break;
1322           }
1323     }
1324   if (dq->count > 1)
1325     {
1326       /* multiple candidates, open a branch */
1327       for (i = 1; i < dq->count; i++)
1328         queue_push(&solv->branches, dq->elements[i]);
1329       queue_push(&solv->branches, -level);
1330     }
1331   p = dq->elements[0];
1332
1333   POOL_DEBUG(SOLV_DEBUG_POLICY, "installing %s\n", pool_solvid2str(pool, p));
1334
1335   return setpropagatelearn(solv, level, p, disablerules, ruleid);
1336 }
1337
1338
1339 /********************************************************************/
1340 /* Main solver interface */
1341
1342
1343 /*-------------------------------------------------------------------
1344  *
1345  * solver_create
1346  * create solver structure
1347  *
1348  * pool: all available solvables
1349  * installed: installed Solvables
1350  *
1351  *
1352  * Upon solving, rules are created to flag the Solvables
1353  * of the 'installed' Repo as installed.
1354  */
1355
1356 Solver *
1357 solver_create(Pool *pool)
1358 {
1359   Solver *solv;
1360   solv = (Solver *)solv_calloc(1, sizeof(Solver));
1361   solv->pool = pool;
1362   solv->installed = pool->installed;
1363
1364   solv->allownamechange = 1;
1365
1366   solv->dup_allowdowngrade = 1;
1367   solv->dup_allownamechange = 1;
1368   solv->dup_allowarchchange = 1;
1369   solv->dup_allowvendorchange = 1;
1370
1371   queue_init(&solv->ruletojob);
1372   queue_init(&solv->decisionq);
1373   queue_init(&solv->decisionq_why);
1374   queue_init(&solv->problems);
1375   queue_init(&solv->orphaned);
1376   queue_init(&solv->learnt_why);
1377   queue_init(&solv->learnt_pool);
1378   queue_init(&solv->branches);
1379   queue_init(&solv->weakruleq);
1380   queue_init(&solv->ruleassertions);
1381
1382   queue_push(&solv->learnt_pool, 0);    /* so that 0 does not describe a proof */
1383
1384   map_init(&solv->recommendsmap, pool->nsolvables);
1385   map_init(&solv->suggestsmap, pool->nsolvables);
1386   map_init(&solv->noupdate, solv->installed ? solv->installed->end - solv->installed->start : 0);
1387   solv->recommends_index = 0;
1388
1389   solv->decisionmap = (Id *)solv_calloc(pool->nsolvables, sizeof(Id));
1390   solv->nrules = 1;
1391   solv->rules = solv_extend_resize(solv->rules, solv->nrules, sizeof(Rule), RULES_BLOCK);
1392   memset(solv->rules, 0, sizeof(Rule));
1393
1394   return solv;
1395 }
1396
1397
1398 /*-------------------------------------------------------------------
1399  *
1400  * solver_free
1401  */
1402
1403 void
1404 solver_free(Solver *solv)
1405 {
1406   queue_free(&solv->job);
1407   queue_free(&solv->ruletojob);
1408   queue_free(&solv->decisionq);
1409   queue_free(&solv->decisionq_why);
1410   queue_free(&solv->learnt_why);
1411   queue_free(&solv->learnt_pool);
1412   queue_free(&solv->problems);
1413   queue_free(&solv->solutions);
1414   queue_free(&solv->orphaned);
1415   queue_free(&solv->branches);
1416   queue_free(&solv->weakruleq);
1417   queue_free(&solv->ruleassertions);
1418   if (solv->cleandeps_updatepkgs)
1419     {
1420       queue_free(solv->cleandeps_updatepkgs);
1421       solv->cleandeps_updatepkgs = solv_free(solv->cleandeps_updatepkgs);
1422     }
1423   if (solv->cleandeps_mistakes)
1424     {
1425       queue_free(solv->cleandeps_mistakes);
1426       solv->cleandeps_mistakes = solv_free(solv->cleandeps_mistakes);
1427     }
1428   if (solv->update_targets)
1429     {
1430       queue_free(solv->update_targets);
1431       solv->update_targets = solv_free(solv->update_targets);
1432     }
1433
1434   map_free(&solv->recommendsmap);
1435   map_free(&solv->suggestsmap);
1436   map_free(&solv->noupdate);
1437   map_free(&solv->weakrulemap);
1438   map_free(&solv->noobsoletes);
1439
1440   map_free(&solv->updatemap);
1441   map_free(&solv->fixmap);
1442   map_free(&solv->dupmap);
1443   map_free(&solv->dupinvolvedmap);
1444   map_free(&solv->droporphanedmap);
1445   map_free(&solv->cleandepsmap);
1446
1447   solv_free(solv->decisionmap);
1448   solv_free(solv->rules);
1449   solv_free(solv->watches);
1450   solv_free(solv->obsoletes);
1451   solv_free(solv->obsoletes_data);
1452   solv_free(solv->multiversionupdaters);
1453   solv_free(solv->choicerules_ref);
1454   solv_free(solv);
1455 }
1456
1457 int
1458 solver_get_flag(Solver *solv, int flag)
1459 {
1460   switch (flag)
1461   {
1462   case SOLVER_FLAG_ALLOW_DOWNGRADE:
1463     return solv->allowdowngrade;
1464   case SOLVER_FLAG_ALLOW_NAMECHANGE:
1465     return solv->allownamechange;
1466   case SOLVER_FLAG_ALLOW_ARCHCHANGE:
1467     return solv->allowarchchange;
1468   case SOLVER_FLAG_ALLOW_VENDORCHANGE:
1469     return solv->allowvendorchange;
1470   case SOLVER_FLAG_ALLOW_UNINSTALL:
1471     return solv->allowuninstall;
1472   case SOLVER_FLAG_NO_UPDATEPROVIDE:
1473     return solv->noupdateprovide;
1474   case SOLVER_FLAG_SPLITPROVIDES:
1475     return solv->dosplitprovides;
1476   case SOLVER_FLAG_IGNORE_RECOMMENDED:
1477     return solv->dontinstallrecommended;
1478   case SOLVER_FLAG_ADD_ALREADY_RECOMMENDED:
1479     return solv->addalreadyrecommended;
1480   case SOLVER_FLAG_NO_INFARCHCHECK:
1481     return solv->noinfarchcheck;
1482   case SOLVER_FLAG_KEEP_EXPLICIT_OBSOLETES:
1483     return solv->keepexplicitobsoletes;
1484   default:
1485     break;
1486   }
1487   return -1;
1488 }
1489
1490 int
1491 solver_set_flag(Solver *solv, int flag, int value)
1492 {
1493   int old = solver_get_flag(solv, flag);
1494   switch (flag)
1495   {
1496   case SOLVER_FLAG_ALLOW_DOWNGRADE:
1497     solv->allowdowngrade = value;
1498     break;
1499   case SOLVER_FLAG_ALLOW_NAMECHANGE:
1500     solv->allownamechange = value;
1501     break;
1502   case SOLVER_FLAG_ALLOW_ARCHCHANGE:
1503     solv->allowarchchange = value;
1504     break;
1505   case SOLVER_FLAG_ALLOW_VENDORCHANGE:
1506     solv->allowvendorchange = value;
1507     break;
1508   case SOLVER_FLAG_ALLOW_UNINSTALL:
1509     solv->allowuninstall = value;
1510     break;
1511   case SOLVER_FLAG_NO_UPDATEPROVIDE:
1512     solv->noupdateprovide = value;
1513     break;
1514   case SOLVER_FLAG_SPLITPROVIDES:
1515     solv->dosplitprovides = value;
1516     break;
1517   case SOLVER_FLAG_IGNORE_RECOMMENDED:
1518     solv->dontinstallrecommended = value;
1519     break;
1520   case SOLVER_FLAG_ADD_ALREADY_RECOMMENDED:
1521     solv->addalreadyrecommended = value;
1522     break;
1523   case SOLVER_FLAG_NO_INFARCHCHECK:
1524     solv->noinfarchcheck = value;
1525     break;
1526   case SOLVER_FLAG_KEEP_EXPLICIT_OBSOLETES:
1527     solv->keepexplicitobsoletes = value;
1528     break;
1529   default:
1530     break;
1531   }
1532   return old;
1533 }
1534
1535 int
1536 cleandeps_check_mistakes(Solver *solv, int level)
1537 {
1538   Pool *pool = solv->pool;
1539   Rule *r;
1540   Id p, *dp;
1541   int i;
1542   int mademistake = 0;
1543
1544   if (!solv->cleandepsmap.size)
1545     return 0;
1546   /* check for mistakes */
1547   for (i = solv->installed->start; i < solv->installed->end; i++)
1548     {
1549       if (!MAPTST(&solv->cleandepsmap, i - solv->installed->start))
1550         continue;
1551       r = solv->rules + solv->featurerules + (i - solv->installed->start);
1552       /* a mistake is when the featurerule is true but the updaterule is false */
1553       if (r->p)
1554         {
1555           FOR_RULELITERALS(p, dp, r)
1556             if (p > 0 && solv->decisionmap[p] > 0)
1557               break;
1558           if (p)
1559             {
1560               r = solv->rules + solv->updaterules + (i - solv->installed->start);
1561               if (!r->p)
1562                 continue;
1563               FOR_RULELITERALS(p, dp, r)
1564                 if (p > 0 && solv->decisionmap[p] > 0)
1565                   break;
1566               if (!p)
1567                 {
1568                   POOL_DEBUG(SOLV_DEBUG_SOLVER, "cleandeps mistake: ");
1569                   solver_printruleclass(solv, SOLV_DEBUG_SOLVER, r);
1570                   POOL_DEBUG(SOLV_DEBUG_SOLVER, "feature rule: ");
1571                   solver_printruleclass(solv, SOLV_DEBUG_SOLVER, solv->rules + solv->featurerules + (i - solv->installed->start));
1572                   if (!solv->cleandeps_mistakes)
1573                     {
1574                       solv->cleandeps_mistakes = solv_calloc(1, sizeof(Queue));
1575                       queue_init(solv->cleandeps_mistakes);
1576                     }
1577                   queue_push(solv->cleandeps_mistakes, i);
1578                   MAPCLR(&solv->cleandepsmap, i - solv->installed->start);
1579                   solver_reenablepolicyrules_cleandeps(solv, i);
1580                   mademistake = 1;
1581                 }
1582             }
1583         }
1584     }
1585   if (mademistake)
1586     solver_reset(solv);
1587   return mademistake;
1588 }
1589
1590 static void
1591 prune_to_update_targets(Solver *solv, Id *cp, Queue *q)
1592 {
1593   int i, j;
1594   Id p, *cp2;
1595   for (i = j = 0; i < q->count; i++)
1596     {
1597       p = q->elements[i];
1598       for (cp2 = cp; *cp2; cp2++)
1599         if (*cp2 == p)
1600           {
1601             q->elements[j++] = p;
1602             break;
1603           }
1604     }
1605   queue_truncate(q, j);
1606 }
1607
1608 /*-------------------------------------------------------------------
1609  *
1610  * solver_run_sat
1611  *
1612  * all rules have been set up, now actually run the solver
1613  *
1614  */
1615
1616 void
1617 solver_run_sat(Solver *solv, int disablerules, int doweak)
1618 {
1619   Queue dq;             /* local decisionqueue */
1620   Queue dqs;            /* local decisionqueue for supplements */
1621   int systemlevel;
1622   int level, olevel;
1623   Rule *r;
1624   int i, j, n;
1625   Solvable *s;
1626   Pool *pool = solv->pool;
1627   Id p, *dp;
1628   int minimizationsteps;
1629   int installedpos = solv->installed ? solv->installed->start : 0;
1630
1631   IF_POOLDEBUG (SOLV_DEBUG_RULE_CREATION)
1632     {
1633       POOL_DEBUG (SOLV_DEBUG_RULE_CREATION, "number of rules: %d\n", solv->nrules);
1634       for (i = 1; i < solv->nrules; i++)
1635         solver_printruleclass(solv, SOLV_DEBUG_RULE_CREATION, solv->rules + i);
1636     }
1637
1638   POOL_DEBUG(SOLV_DEBUG_SOLVER, "initial decisions: %d\n", solv->decisionq.count);
1639
1640   /* start SAT algorithm */
1641   level = 1;
1642   systemlevel = level + 1;
1643   POOL_DEBUG(SOLV_DEBUG_SOLVER, "solving...\n");
1644
1645   queue_init(&dq);
1646   queue_init(&dqs);
1647
1648   /*
1649    * here's the main loop:
1650    * 1) propagate new decisions (only needed once)
1651    * 2) fulfill jobs
1652    * 3) try to keep installed packages
1653    * 4) fulfill all unresolved rules
1654    * 5) install recommended packages
1655    * 6) minimalize solution if we had choices
1656    * if we encounter a problem, we rewind to a safe level and restart
1657    * with step 1
1658    */
1659
1660   minimizationsteps = 0;
1661   for (;;)
1662     {
1663       /*
1664        * initial propagation of the assertions
1665        */
1666       if (level == 1)
1667         {
1668           POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "propagating (propagate_index: %d;  size decisionq: %d)...\n", solv->propagate_index, solv->decisionq.count);
1669           if ((r = propagate(solv, level)) != 0)
1670             {
1671               if (analyze_unsolvable(solv, r, disablerules))
1672                 continue;
1673               level = 0;
1674               break;    /* unsolvable */
1675             }
1676         }
1677
1678       /*
1679        * resolve jobs first
1680        */
1681      if (level < systemlevel)
1682         {
1683           POOL_DEBUG(SOLV_DEBUG_SOLVER, "resolving job rules\n");
1684           for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
1685             {
1686               Id l;
1687               if (r->d < 0)             /* ignore disabled rules */
1688                 continue;
1689               queue_empty(&dq);
1690               FOR_RULELITERALS(l, dp, r)
1691                 {
1692                   if (l < 0)
1693                     {
1694                       if (solv->decisionmap[-l] <= 0)
1695                         break;
1696                     }
1697                   else
1698                     {
1699                       if (solv->decisionmap[l] > 0)
1700                         break;
1701                       if (solv->decisionmap[l] == 0)
1702                         queue_push(&dq, l);
1703                     }
1704                 }
1705               if (l || !dq.count)
1706                 continue;
1707               /* prune to installed if not updating */
1708               if (dq.count > 1 && solv->installed && !solv->updatemap_all &&
1709                   !(solv->job.elements[solv->ruletojob.elements[i - solv->jobrules]] & SOLVER_ORUPDATE))
1710                 {
1711                   int j, k;
1712                   for (j = k = 0; j < dq.count; j++)
1713                     {
1714                       Solvable *s = pool->solvables + dq.elements[j];
1715                       if (s->repo == solv->installed)
1716                         {
1717                           dq.elements[k++] = dq.elements[j];
1718                           if (solv->updatemap.size && MAPTST(&solv->updatemap, dq.elements[j] - solv->installed->start))
1719                             {
1720                               k = 0;    /* package wants to be updated, do not prune */
1721                               break;
1722                             }
1723                         }
1724                     }
1725                   if (k)
1726                     dq.count = k;
1727                 }
1728               olevel = level;
1729               level = selectandinstall(solv, level, &dq, disablerules, i);
1730               if (level == 0)
1731                 break;
1732               if (level <= olevel)
1733                 break;
1734             }
1735           if (level == 0)
1736             break;      /* unsolvable */
1737           systemlevel = level + 1;
1738           if (i < solv->jobrules_end)
1739             continue;
1740           solv->decisioncnt_update = solv->decisionq.count;
1741           solv->decisioncnt_keep = solv->decisionq.count;
1742         }
1743
1744       /*
1745        * installed packages
1746        */
1747       if (level < systemlevel && solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
1748         {
1749           Repo *installed = solv->installed;
1750           int pass;
1751
1752           POOL_DEBUG(SOLV_DEBUG_SOLVER, "resolving installed packages\n");
1753           /* we use two passes if we need to update packages
1754            * to create a better user experience */
1755           for (pass = solv->updatemap.size ? 0 : 1; pass < 2; pass++)
1756             {
1757               int passlevel = level;
1758               if (pass == 1)
1759                 solv->decisioncnt_keep = solv->decisionq.count;
1760               /* start with installedpos, the position that gave us problems last time */
1761               for (i = installedpos, n = installed->start; n < installed->end; i++, n++)
1762                 {
1763                   Rule *rr;
1764                   Id d;
1765
1766                   if (i == installed->end)
1767                     i = installed->start;
1768                   s = pool->solvables + i;
1769                   if (s->repo != installed)
1770                     continue;
1771
1772                   if (solv->decisionmap[i] > 0)
1773                     continue;
1774                   if (!pass && solv->updatemap.size && !MAPTST(&solv->updatemap, i - installed->start))
1775                     continue;           /* updates first */
1776                   r = solv->rules + solv->updaterules + (i - installed->start);
1777                   rr = r;
1778                   if (!rr->p || rr->d < 0)      /* disabled -> look at feature rule */
1779                     rr -= solv->installed->end - solv->installed->start;
1780                   if (!rr->p)           /* identical to update rule? */
1781                     rr = r;
1782                   if (!rr->p)
1783                     continue;           /* orpaned package */
1784
1785                   /* XXX: noupdate check is probably no longer needed, as all jobs should
1786                    * already be satisfied */
1787                   /* Actually we currently still need it because of erase jobs */
1788                   /* if noupdate is set we do not look at update candidates */
1789                   queue_empty(&dq);
1790                   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))
1791                     {
1792                       if (solv->noobsoletes.size && solv->multiversionupdaters
1793                              && (d = solv->multiversionupdaters[i - installed->start]) != 0)
1794                         {
1795                           /* special multiversion handling, make sure best version is chosen */
1796                           queue_push(&dq, i);
1797                           while ((p = pool->whatprovidesdata[d++]) != 0)
1798                             if (solv->decisionmap[p] >= 0)
1799                               queue_push(&dq, p);
1800                           if (dq.count && solv->update_targets && solv->update_targets->elements[i - installed->start])
1801                             prune_to_update_targets(solv, solv->update_targets->elements + solv->update_targets->elements[i - installed->start], &dq);
1802                           if (dq.count)
1803                             {
1804                               policy_filter_unwanted(solv, &dq, POLICY_MODE_CHOOSE);
1805                               p = dq.elements[0];
1806                               if (p != i && solv->decisionmap[p] == 0)
1807                                 {
1808                                   rr = solv->rules + solv->featurerules + (i - solv->installed->start);
1809                                   if (!rr->p)           /* update rule == feature rule? */
1810                                     rr = rr - solv->featurerules + solv->updaterules;
1811                                   dq.count = 1;
1812                                 }
1813                               else
1814                                 dq.count = 0;
1815                             }
1816                         }
1817                       else
1818                         {
1819                           /* update to best package */
1820                           FOR_RULELITERALS(p, dp, rr)
1821                             {
1822                               if (solv->decisionmap[p] > 0)
1823                                 {
1824                                   dq.count = 0;         /* already fulfilled */
1825                                   break;
1826                                 }
1827                               if (!solv->decisionmap[p])
1828                                 queue_push(&dq, p);
1829                             }
1830                         }
1831                     }
1832                   if (dq.count && solv->update_targets && solv->update_targets->elements[i - installed->start])
1833                     prune_to_update_targets(solv, solv->update_targets->elements + solv->update_targets->elements[i - installed->start], &dq);
1834                   /* install best version */
1835                   if (dq.count)
1836                     {
1837                       olevel = level;
1838                       level = selectandinstall(solv, level, &dq, disablerules, rr - solv->rules);
1839                       if (level == 0)
1840                         {
1841                           queue_free(&dq);
1842                           queue_free(&dqs);
1843                           return;
1844                         }
1845                       if (level <= olevel)
1846                         {
1847                           if (level == 1 || level < passlevel)
1848                             break;      /* trouble */
1849                           if (level < olevel)
1850                             n = installed->start;       /* redo all */
1851                           i--;
1852                           n--;
1853                           continue;
1854                         }
1855                     }
1856                   /* if still undecided keep package */
1857                   if (solv->decisionmap[i] == 0)
1858                     {
1859                       olevel = level;
1860                       if (solv->cleandepsmap.size && MAPTST(&solv->cleandepsmap, i - installed->start))
1861                         {
1862                           POOL_DEBUG(SOLV_DEBUG_POLICY, "cleandeps erasing %s\n", pool_solvid2str(pool, i));
1863                           level = setpropagatelearn(solv, level, -i, disablerules, 0);
1864                         }
1865                       else
1866                         {
1867                           POOL_DEBUG(SOLV_DEBUG_POLICY, "keeping %s\n", pool_solvid2str(pool, i));
1868                           level = setpropagatelearn(solv, level, i, disablerules, r - solv->rules);
1869                         }
1870                       if (level == 0)
1871                         break;
1872                       if (level <= olevel)
1873                         {
1874                           if (level == 1 || level < passlevel)
1875                             break;      /* trouble */
1876                           if (level < olevel)
1877                             n = installed->start;       /* redo all */
1878                           i--;
1879                           n--;
1880                           continue;     /* retry with learnt rule */
1881                         }
1882                     }
1883                 }
1884               if (n < installed->end)
1885                 {
1886                   installedpos = i;     /* retry problem solvable next time */
1887                   break;                /* ran into trouble */
1888                 }
1889               installedpos = installed->start;  /* reset installedpos */
1890             }
1891           if (level == 0)
1892             break;              /* unsolvable */
1893           systemlevel = level + 1;
1894           if (pass < 2)
1895             continue;           /* had trouble, retry */
1896         }
1897
1898       if (level < systemlevel)
1899         systemlevel = level;
1900
1901       /*
1902        * decide
1903        */
1904       solv->decisioncnt_resolve = solv->decisionq.count;
1905       POOL_DEBUG(SOLV_DEBUG_POLICY, "deciding unresolved rules\n");
1906       for (i = 1, n = 1; n < solv->nrules; i++, n++)
1907         {
1908           if (i == solv->nrules)
1909             i = 1;
1910           r = solv->rules + i;
1911           if (r->d < 0)         /* ignore disabled rules */
1912             continue;
1913           queue_empty(&dq);
1914           if (r->d == 0)
1915             {
1916               /* binary or unary rule */
1917               /* need two positive undecided literals */
1918               if (r->p < 0 || r->w2 <= 0)
1919                 continue;
1920               if (solv->decisionmap[r->p] || solv->decisionmap[r->w2])
1921                 continue;
1922               queue_push(&dq, r->p);
1923               queue_push(&dq, r->w2);
1924             }
1925           else
1926             {
1927               /* make sure that
1928                * all negative literals are installed
1929                * no positive literal is installed
1930                * i.e. the rule is not fulfilled and we
1931                * just need to decide on the positive literals
1932                */
1933               if (r->p < 0)
1934                 {
1935                   if (solv->decisionmap[-r->p] <= 0)
1936                     continue;
1937                 }
1938               else
1939                 {
1940                   if (solv->decisionmap[r->p] > 0)
1941                     continue;
1942                   if (solv->decisionmap[r->p] == 0)
1943                     queue_push(&dq, r->p);
1944                 }
1945               dp = pool->whatprovidesdata + r->d;
1946               while ((p = *dp++) != 0)
1947                 {
1948                   if (p < 0)
1949                     {
1950                       if (solv->decisionmap[-p] <= 0)
1951                         break;
1952                     }
1953                   else
1954                     {
1955                       if (solv->decisionmap[p] > 0)
1956                         break;
1957                       if (solv->decisionmap[p] == 0)
1958                         queue_push(&dq, p);
1959                     }
1960                 }
1961               if (p)
1962                 continue;
1963             }
1964           IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
1965             {
1966               POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "unfulfilled ");
1967               solver_printruleclass(solv, SOLV_DEBUG_PROPAGATE, r);
1968             }
1969           /* dq.count < 2 cannot happen as this means that
1970            * the rule is unit */
1971           assert(dq.count > 1);
1972
1973           olevel = level;
1974           level = selectandinstall(solv, level, &dq, disablerules, r - solv->rules);
1975           if (level == 0)
1976             break;              /* unsolvable */
1977           if (level < systemlevel || level == 1)
1978             break;              /* trouble */
1979           /* something changed, so look at all rules again */
1980           n = 0;
1981         }
1982
1983       if (n != solv->nrules)    /* ran into trouble? */
1984         {
1985           if (level == 0)
1986             break;              /* unsolvable */
1987           continue;             /* start over */
1988         }
1989
1990       /* at this point we have a consistent system. now do the extras... */
1991
1992       solv->decisioncnt_weak = solv->decisionq.count;
1993       if (doweak)
1994         {
1995           int qcount;
1996
1997           POOL_DEBUG(SOLV_DEBUG_POLICY, "installing recommended packages\n");
1998           queue_empty(&dq);     /* recommended packages */
1999           queue_empty(&dqs);    /* supplemented packages */
2000           for (i = 1; i < pool->nsolvables; i++)
2001             {
2002               if (solv->decisionmap[i] < 0)
2003                 continue;
2004               if (solv->decisionmap[i] > 0)
2005                 {
2006                   /* installed, check for recommends */
2007                   Id *recp, rec, pp, p;
2008                   s = pool->solvables + i;
2009                   if (!solv->addalreadyrecommended && s->repo == solv->installed)
2010                     continue;
2011                   /* XXX need to special case AND ? */
2012                   if (s->recommends)
2013                     {
2014                       recp = s->repo->idarraydata + s->recommends;
2015                       while ((rec = *recp++) != 0)
2016                         {
2017                           qcount = dq.count;
2018                           FOR_PROVIDES(p, pp, rec)
2019                             {
2020                               if (solv->decisionmap[p] > 0)
2021                                 {
2022                                   dq.count = qcount;
2023                                   break;
2024                                 }
2025                               else if (solv->decisionmap[p] == 0)
2026                                 {
2027                                   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))))
2028                                     continue;
2029                                   queue_pushunique(&dq, p);
2030                                 }
2031                             }
2032                         }
2033                     }
2034                 }
2035               else
2036                 {
2037                   s = pool->solvables + i;
2038                   if (!s->supplements)
2039                     continue;
2040                   if (!pool_installable(pool, s))
2041                     continue;
2042                   if (!solver_is_supplementing(solv, s))
2043                     continue;
2044                   if (solv->dupmap_all && solv->installed && s->repo == solv->installed && (solv->droporphanedmap_all || (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, i - solv->installed->start))))
2045                     continue;
2046                   queue_push(&dqs, i);
2047                 }
2048             }
2049
2050           /* filter out all packages obsoleted by installed packages */
2051           /* this is no longer needed if we have reverse obsoletes */
2052           if ((dqs.count || dq.count) && solv->installed)
2053             {
2054               Map obsmap;
2055               Id obs, *obsp, po, ppo;
2056
2057               map_init(&obsmap, pool->nsolvables);
2058               for (p = solv->installed->start; p < solv->installed->end; p++)
2059                 {
2060                   s = pool->solvables + p;
2061                   if (s->repo != solv->installed || !s->obsoletes)
2062                     continue;
2063                   if (solv->decisionmap[p] <= 0)
2064                     continue;
2065                   if (solv->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
2066                     continue;
2067                   obsp = s->repo->idarraydata + s->obsoletes;
2068                   /* foreach obsoletes */
2069                   while ((obs = *obsp++) != 0)
2070                     FOR_PROVIDES(po, ppo, obs)
2071                       MAPSET(&obsmap, po);
2072                 }
2073               for (i = j = 0; i < dqs.count; i++)
2074                 if (!MAPTST(&obsmap, dqs.elements[i]))
2075                   dqs.elements[j++] = dqs.elements[i];
2076               dqs.count = j;
2077               for (i = j = 0; i < dq.count; i++)
2078                 if (!MAPTST(&obsmap, dq.elements[i]))
2079                   dq.elements[j++] = dq.elements[i];
2080               dq.count = j;
2081               map_free(&obsmap);
2082             }
2083
2084           /* filter out all already supplemented packages if requested */
2085           if (!solv->addalreadyrecommended && dqs.count)
2086             {
2087               /* turn off all new packages */
2088               for (i = 0; i < solv->decisionq.count; i++)
2089                 {
2090                   p = solv->decisionq.elements[i];
2091                   if (p < 0)
2092                     continue;
2093                   s = pool->solvables + p;
2094                   if (s->repo && s->repo != solv->installed)
2095                     solv->decisionmap[p] = -solv->decisionmap[p];
2096                 }
2097               /* filter out old supplements */
2098               for (i = j = 0; i < dqs.count; i++)
2099                 {
2100                   p = dqs.elements[i];
2101                   s = pool->solvables + p;
2102                   if (!s->supplements)
2103                     continue;
2104                   if (!solver_is_supplementing(solv, s))
2105                     dqs.elements[j++] = p;
2106                 }
2107               dqs.count = j;
2108               /* undo turning off */
2109               for (i = 0; i < solv->decisionq.count; i++)
2110                 {
2111                   p = solv->decisionq.elements[i];
2112                   if (p < 0)
2113                     continue;
2114                   s = pool->solvables + p;
2115                   if (s->repo && s->repo != solv->installed)
2116                     solv->decisionmap[p] = -solv->decisionmap[p];
2117                 }
2118             }
2119
2120           /* multiversion doesn't mix well with supplements.
2121            * filter supplemented packages where we already decided
2122            * to install a different version (see bnc#501088) */
2123           if (dqs.count && solv->noobsoletes.size)
2124             {
2125               for (i = j = 0; i < dqs.count; i++)
2126                 {
2127                   p = dqs.elements[i];
2128                   if (MAPTST(&solv->noobsoletes, p))
2129                     {
2130                       Id p2, pp2;
2131                       s = pool->solvables + p;
2132                       FOR_PROVIDES(p2, pp2, s->name)
2133                         if (solv->decisionmap[p2] > 0 && pool->solvables[p2].name == s->name)
2134                           break;
2135                       if (p2)
2136                         continue;       /* ignore this package */
2137                     }
2138                   dqs.elements[j++] = p;
2139                 }
2140               dqs.count = j;
2141             }
2142
2143           /* make dq contain both recommended and supplemented pkgs */
2144           if (dqs.count)
2145             {
2146               for (i = 0; i < dqs.count; i++)
2147                 queue_pushunique(&dq, dqs.elements[i]);
2148             }
2149
2150           if (dq.count)
2151             {
2152               Map dqmap;
2153               int decisioncount = solv->decisionq.count;
2154
2155               if (dq.count == 1)
2156                 {
2157                   /* simple case, just one package. no need to choose to best version */
2158                   p = dq.elements[0];
2159                   if (dqs.count)
2160                     POOL_DEBUG(SOLV_DEBUG_POLICY, "installing supplemented %s\n", pool_solvid2str(pool, p));
2161                   else
2162                     POOL_DEBUG(SOLV_DEBUG_POLICY, "installing recommended %s\n", pool_solvid2str(pool, p));
2163                   level = setpropagatelearn(solv, level, p, 0, 0);
2164                   if (level == 0)
2165                     break;
2166                   continue;     /* back to main loop */
2167                 }
2168
2169               /* filter packages, this gives us the best versions */
2170               policy_filter_unwanted(solv, &dq, POLICY_MODE_RECOMMEND);
2171
2172               /* create map of result */
2173               map_init(&dqmap, pool->nsolvables);
2174               for (i = 0; i < dq.count; i++)
2175                 MAPSET(&dqmap, dq.elements[i]);
2176
2177               /* install all supplemented packages */
2178               for (i = 0; i < dqs.count; i++)
2179                 {
2180                   p = dqs.elements[i];
2181                   if (solv->decisionmap[p] || !MAPTST(&dqmap, p))
2182                     continue;
2183                   POOL_DEBUG(SOLV_DEBUG_POLICY, "installing supplemented %s\n", pool_solvid2str(pool, p));
2184                   olevel = level;
2185                   level = setpropagatelearn(solv, level, p, 0, 0);
2186                   if (level <= olevel)
2187                     break;
2188                 }
2189               if (i < dqs.count || solv->decisionq.count < decisioncount)
2190                 {
2191                   map_free(&dqmap);
2192                   if (level == 0)
2193                     break;
2194                   continue;
2195                 }
2196
2197               /* install all recommended packages */
2198               /* more work as we want to created branches if multiple
2199                * choices are valid */
2200               for (i = 0; i < decisioncount; i++)
2201                 {
2202                   Id rec, *recp, pp;
2203                   p = solv->decisionq.elements[i];
2204                   if (p < 0)
2205                     continue;
2206                   s = pool->solvables + p;
2207                   if (!s->repo || (!solv->addalreadyrecommended && s->repo == solv->installed))
2208                     continue;
2209                   if (!s->recommends)
2210                     continue;
2211                   recp = s->repo->idarraydata + s->recommends;
2212                   while ((rec = *recp++) != 0)
2213                     {
2214                       queue_empty(&dq);
2215                       FOR_PROVIDES(p, pp, rec)
2216                         {
2217                           if (solv->decisionmap[p] > 0)
2218                             {
2219                               dq.count = 0;
2220                               break;
2221                             }
2222                           else if (solv->decisionmap[p] == 0 && MAPTST(&dqmap, p))
2223                             queue_pushunique(&dq, p);
2224                         }
2225                       if (!dq.count)
2226                         continue;
2227                       if (dq.count > 1)
2228                         {
2229                           /* multiple candidates, open a branch */
2230                           for (i = 1; i < dq.count; i++)
2231                             queue_push(&solv->branches, dq.elements[i]);
2232                           queue_push(&solv->branches, -level);
2233                         }
2234                       p = dq.elements[0];
2235                       POOL_DEBUG(SOLV_DEBUG_POLICY, "installing recommended %s\n", pool_solvid2str(pool, p));
2236                       olevel = level;
2237                       level = setpropagatelearn(solv, level, p, 0, 0);
2238                       if (level <= olevel || solv->decisionq.count < decisioncount)
2239                         break;  /* we had to revert some decisions */
2240                     }
2241                   if (rec)
2242                     break;      /* had a problem above, quit loop */
2243                 }
2244               map_free(&dqmap);
2245               if (level == 0)
2246                 break;
2247               continue;         /* back to main loop so that all deps are checked */
2248             }
2249         }
2250
2251       solv->decisioncnt_orphan = solv->decisionq.count;
2252       if (solv->dupmap_all && solv->installed)
2253         {
2254           int installedone = 0;
2255
2256           /* let's see if we can install some unsupported package */
2257           POOL_DEBUG(SOLV_DEBUG_SOLVER, "deciding orphaned packages\n");
2258           for (i = 0; i < solv->orphaned.count; i++)
2259             {
2260               p = solv->orphaned.elements[i];
2261               if (solv->decisionmap[p])
2262                 continue;       /* already decided */
2263               if (solv->droporphanedmap_all)
2264                 continue;
2265               if (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))
2266                 continue;
2267               POOL_DEBUG(SOLV_DEBUG_SOLVER, "keeping orphaned %s\n", pool_solvid2str(pool, p));
2268               olevel = level;
2269               level = setpropagatelearn(solv, level, p, 0, 0);
2270               installedone = 1;
2271               if (level < olevel)
2272                 break;
2273             }
2274           if (installedone || i < solv->orphaned.count)
2275             {
2276               if (level == 0)
2277                 break;
2278               continue;         /* back to main loop */
2279             }
2280           for (i = 0; i < solv->orphaned.count; i++)
2281             {
2282               p = solv->orphaned.elements[i];
2283               if (solv->decisionmap[p])
2284                 continue;       /* already decided */
2285               POOL_DEBUG(SOLV_DEBUG_SOLVER, "removing orphaned %s\n", pool_solvid2str(pool, p));
2286               olevel = level;
2287               level = setpropagatelearn(solv, level, -p, 0, 0);
2288               if (level < olevel)
2289                 break;
2290             }
2291           if (i < solv->orphaned.count)
2292             {
2293               if (level == 0)
2294                 break;
2295               continue;         /* back to main loop */
2296             }
2297         }
2298
2299      if (solv->installed && solv->cleandepsmap.size)
2300         {
2301           if (cleandeps_check_mistakes(solv, level))
2302             {
2303               level = 1;        /* restart from scratch */
2304               continue;
2305             }
2306         }
2307
2308      if (solv->solution_callback)
2309         {
2310           solv->solution_callback(solv, solv->solution_callback_data);
2311           if (solv->branches.count)
2312             {
2313               int i = solv->branches.count - 1;
2314               int l = -solv->branches.elements[i];
2315               Id why;
2316
2317               for (; i > 0; i--)
2318                 if (solv->branches.elements[i - 1] < 0)
2319                   break;
2320               p = solv->branches.elements[i];
2321               POOL_DEBUG(SOLV_DEBUG_SOLVER, "branching with %s\n", pool_solvid2str(pool, p));
2322               queue_empty(&dq);
2323               for (j = i + 1; j < solv->branches.count; j++)
2324                 queue_push(&dq, solv->branches.elements[j]);
2325               solv->branches.count = i;
2326               level = l;
2327               revert(solv, level);
2328               if (dq.count > 1)
2329                 for (j = 0; j < dq.count; j++)
2330                   queue_push(&solv->branches, dq.elements[j]);
2331               olevel = level;
2332               why = -solv->decisionq_why.elements[solv->decisionq_why.count];
2333               assert(why >= 0);
2334               level = setpropagatelearn(solv, level, p, disablerules, why);
2335               if (level == 0)
2336                 break;
2337               continue;
2338             }
2339           /* all branches done, we're finally finished */
2340           break;
2341         }
2342
2343       /* auto-minimization step */
2344      if (solv->branches.count)
2345         {
2346           int l = 0, lasti = -1, lastl = -1;
2347           Id why;
2348
2349           p = 0;
2350           for (i = solv->branches.count - 1; i >= 0; i--)
2351             {
2352               p = solv->branches.elements[i];
2353               if (p < 0)
2354                 l = -p;
2355               else if (p > 0 && solv->decisionmap[p] > l + 1)
2356                 {
2357                   lasti = i;
2358                   lastl = l;
2359                 }
2360             }
2361           if (lasti >= 0)
2362             {
2363               /* kill old solvable so that we do not loop */
2364               p = solv->branches.elements[lasti];
2365               solv->branches.elements[lasti] = 0;
2366               POOL_DEBUG(SOLV_DEBUG_SOLVER, "minimizing %d -> %d with %s\n", solv->decisionmap[p], lastl, pool_solvid2str(pool, p));
2367               minimizationsteps++;
2368
2369               level = lastl;
2370               revert(solv, level);
2371               why = -solv->decisionq_why.elements[solv->decisionq_why.count];
2372               assert(why >= 0);
2373               olevel = level;
2374               level = setpropagatelearn(solv, level, p, disablerules, why);
2375               if (level == 0)
2376                 break;
2377               continue;         /* back to main loop */
2378             }
2379         }
2380       /* no minimization found, we're finally finished! */
2381       break;
2382     }
2383
2384   POOL_DEBUG(SOLV_DEBUG_STATS, "solver statistics: %d learned rules, %d unsolvable, %d minimization steps\n", solv->stats_learned, solv->stats_unsolvable, minimizationsteps);
2385
2386   POOL_DEBUG(SOLV_DEBUG_STATS, "done solving.\n\n");
2387   queue_free(&dq);
2388   queue_free(&dqs);
2389   if (level == 0)
2390     {
2391       /* unsolvable */
2392       solv->decisioncnt_update = solv->decisionq.count;
2393       solv->decisioncnt_keep = solv->decisionq.count;
2394       solv->decisioncnt_resolve = solv->decisionq.count;
2395       solv->decisioncnt_weak = solv->decisionq.count;
2396       solv->decisioncnt_orphan = solv->decisionq.count;
2397     }
2398 #if 0
2399   solver_printdecisionq(solv, SOLV_DEBUG_RESULT);
2400 #endif
2401 }
2402
2403
2404 /*-------------------------------------------------------------------
2405  *
2406  * remove disabled conflicts
2407  *
2408  * purpose: update the decisionmap after some rules were disabled.
2409  * this is used to calculate the suggested/recommended package list.
2410  * Also returns a "removed" list to undo the discisionmap changes.
2411  */
2412
2413 static void
2414 removedisabledconflicts(Solver *solv, Queue *removed)
2415 {
2416   Pool *pool = solv->pool;
2417   int i, n;
2418   Id p, why, *dp;
2419   Id new;
2420   Rule *r;
2421   Id *decisionmap = solv->decisionmap;
2422
2423   queue_empty(removed);
2424   for (i = 0; i < solv->decisionq.count; i++)
2425     {
2426       p = solv->decisionq.elements[i];
2427       if (p > 0)
2428         continue;       /* conflicts only, please */
2429       why = solv->decisionq_why.elements[i];
2430       if (why == 0)
2431         {
2432           /* no rule involved, must be a orphan package drop */
2433           continue;
2434         }
2435       /* we never do conflicts on free decisions, so there
2436        * must have been an unit rule */
2437       assert(why > 0);
2438       r = solv->rules + why;
2439       if (r->d < 0 && decisionmap[-p])
2440         {
2441           /* rule is now disabled, remove from decisionmap */
2442           POOL_DEBUG(SOLV_DEBUG_SOLVER, "removing conflict for package %s[%d]\n", pool_solvid2str(pool, -p), -p);
2443           queue_push(removed, -p);
2444           queue_push(removed, decisionmap[-p]);
2445           decisionmap[-p] = 0;
2446         }
2447     }
2448   if (!removed->count)
2449     return;
2450   /* we removed some confliced packages. some of them might still
2451    * be in conflict, so search for unit rules and re-conflict */
2452   new = 0;
2453   for (i = n = 1, r = solv->rules + i; n < solv->nrules; i++, r++, n++)
2454     {
2455       if (i == solv->nrules)
2456         {
2457           i = 1;
2458           r = solv->rules + i;
2459         }
2460       if (r->d < 0)
2461         continue;
2462       if (!r->w2)
2463         {
2464           if (r->p < 0 && !decisionmap[-r->p])
2465             new = r->p;
2466         }
2467       else if (!r->d)
2468         {
2469           /* binary rule */
2470           if (r->p < 0 && decisionmap[-r->p] == 0 && DECISIONMAP_FALSE(r->w2))
2471             new = r->p;
2472           else if (r->w2 < 0 && decisionmap[-r->w2] == 0 && DECISIONMAP_FALSE(r->p))
2473             new = r->w2;
2474         }
2475       else
2476         {
2477           if (r->p < 0 && decisionmap[-r->p] == 0)
2478             new = r->p;
2479           if (new || DECISIONMAP_FALSE(r->p))
2480             {
2481               dp = pool->whatprovidesdata + r->d;
2482               while ((p = *dp++) != 0)
2483                 {
2484                   if (new && p == new)
2485                     continue;
2486                   if (p < 0 && decisionmap[-p] == 0)
2487                     {
2488                       if (new)
2489                         {
2490                           new = 0;
2491                           break;
2492                         }
2493                       new = p;
2494                     }
2495                   else if (!DECISIONMAP_FALSE(p))
2496                     {
2497                       new = 0;
2498                       break;
2499                     }
2500                 }
2501             }
2502         }
2503       if (new)
2504         {
2505           POOL_DEBUG(SOLV_DEBUG_SOLVER, "re-conflicting package %s[%d]\n", pool_solvid2str(pool, -new), -new);
2506           decisionmap[-new] = -1;
2507           new = 0;
2508           n = 0;        /* redo all rules */
2509         }
2510     }
2511 }
2512
2513 static inline void
2514 undo_removedisabledconflicts(Solver *solv, Queue *removed)
2515 {
2516   int i;
2517   for (i = 0; i < removed->count; i += 2)
2518     solv->decisionmap[removed->elements[i]] = removed->elements[i + 1];
2519 }
2520
2521
2522 /*-------------------------------------------------------------------
2523  *
2524  * weaken solvable dependencies
2525  */
2526
2527 static void
2528 weaken_solvable_deps(Solver *solv, Id p)
2529 {
2530   int i;
2531   Rule *r;
2532
2533   for (i = 1, r = solv->rules + i; i < solv->rpmrules_end; i++, r++)
2534     {
2535       if (r->p != -p)
2536         continue;
2537       if ((r->d == 0 || r->d == -1) && r->w2 < 0)
2538         continue;       /* conflict */
2539       queue_push(&solv->weakruleq, i);
2540     }
2541 }
2542
2543
2544 /********************************************************************/
2545 /* main() */
2546
2547
2548 void
2549 solver_calculate_noobsmap(Pool *pool, Queue *job, Map *noobsmap)
2550 {
2551   int i;
2552   Id how, what, select;
2553   Id p, pp;
2554   for (i = 0; i < job->count; i += 2)
2555     {
2556       how = job->elements[i];
2557       if ((how & SOLVER_JOBMASK) != SOLVER_NOOBSOLETES)
2558         continue;
2559       what = job->elements[i + 1];
2560       select = how & SOLVER_SELECTMASK;
2561       if (!noobsmap->size)
2562         map_grow(noobsmap, pool->nsolvables);
2563       if (select == SOLVER_SOLVABLE_ALL)
2564         {
2565           FOR_POOL_SOLVABLES(p)
2566             MAPSET(noobsmap, p);
2567         }
2568       else if (select == SOLVER_SOLVABLE_REPO)
2569         {
2570           Solvable *s;
2571           Repo *repo = pool_id2repo(pool, what);
2572           if (repo)
2573             FOR_REPO_SOLVABLES(repo, p, s)
2574               MAPSET(noobsmap, p);
2575         }
2576       FOR_JOB_SELECT(p, pp, select, what)
2577         MAPSET(noobsmap, p);
2578     }
2579 }
2580
2581 /*
2582  * add a rule created by a job, record job number and weak flag
2583  */
2584 static inline void
2585 solver_addjobrule(Solver *solv, Id p, Id d, Id job, int weak)
2586 {
2587   solver_addrule(solv, p, d);
2588   queue_push(&solv->ruletojob, job);
2589   if (weak)
2590     queue_push(&solv->weakruleq, solv->nrules - 1);
2591 }
2592
2593 static void
2594 add_update_target(Solver *solv, Id p)
2595 {
2596   Pool *pool = solv->pool;
2597   Solvable *s = pool->solvables + p;
2598   Repo *installed = solv->installed;
2599   Id pi, pip;
2600   if (!solv->update_targets)
2601     {
2602       solv->update_targets = solv_calloc(1, sizeof(Queue));
2603       queue_init(solv->update_targets);
2604     }
2605   FOR_PROVIDES(pi, pip, s->name)
2606     {
2607       Solvable *si = pool->solvables + pi;
2608       if (si->name != s->name || si->repo != installed)
2609         continue;
2610       queue_push2(solv->update_targets, pi, p);
2611     }
2612   if (s->obsoletes)
2613     {
2614       Id obs, *obsp = s->repo->idarraydata + s->obsoletes;
2615       while ((obs = *obsp++) != 0)
2616         {
2617           FOR_PROVIDES(pi, pip, obs)
2618             {
2619               Solvable *si = pool->solvables + pi;
2620               if (si->repo != installed)
2621                 continue;
2622               if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, si, obs))
2623                 continue;
2624               if (pool->obsoleteusescolors && !pool_colormatch(pool, s, si))
2625                 continue;
2626               queue_push2(solv->update_targets, pi, p);
2627             }
2628         }
2629     }
2630 }
2631
2632 static int
2633 transform_update_targets_sortfn(const void *ap, const void *bp, void *dp)
2634 {
2635   const Id *a = ap;
2636   const Id *b = bp;
2637   if (a[0] - b[0])
2638     return a[0] - b[0];
2639   return a[1] - b[1];
2640 }
2641
2642 static void
2643 transform_update_targets(Solver *solv)
2644 {
2645   Repo *installed = solv->installed;
2646   Queue *update_targets = solv->update_targets;
2647   int i, j;
2648   Id p, lastp;
2649
2650   if (!update_targets->count)
2651     {
2652       queue_free(update_targets);
2653       solv->update_targets = solv_free(update_targets);
2654       return;
2655     }
2656   if (update_targets->count > 2)
2657     solv_sort(update_targets->elements, update_targets->count >> 1, 2 * sizeof(Id), transform_update_targets_sortfn, solv);
2658   queue_insertn(update_targets, 0, installed->end - installed->start);
2659   lastp = 0;
2660   for (i = j = installed->end - installed->start; i < update_targets->count; i += 2)
2661     {
2662       p = update_targets->elements[i];
2663       if (p != lastp)
2664         {
2665           if (!solv->updatemap.size)
2666             map_grow(&solv->updatemap, installed->end - installed->start);
2667           MAPSET(&solv->updatemap, p - installed->start);
2668           update_targets->elements[j++] = 0;
2669           update_targets->elements[p - installed->start] = j;
2670           lastp = p;
2671         }
2672       update_targets->elements[j++] = update_targets->elements[i + 1];
2673     }
2674   queue_truncate(update_targets, j);
2675   queue_push(update_targets, 0);
2676 }
2677
2678
2679 /*
2680  *
2681  * solve job queue
2682  *
2683  */
2684
2685 int
2686 solver_solve(Solver *solv, Queue *job)
2687 {
2688   Pool *pool = solv->pool;
2689   Repo *installed = solv->installed;
2690   int i;
2691   int oldnrules;
2692   Map addedmap;                /* '1' == have rpm-rules for solvable */
2693   Map installcandidatemap;
2694   Id how, what, select, name, weak, p, pp, d;
2695   Queue q;
2696   Solvable *s;
2697   Rule *r;
2698   int now, solve_start;
2699   int hasdupjob = 0;
2700
2701   solve_start = solv_timems(0);
2702
2703   /* log solver options */
2704   POOL_DEBUG(SOLV_DEBUG_STATS, "solver started\n");
2705   POOL_DEBUG(SOLV_DEBUG_STATS, "dosplitprovides=%d, noupdateprovide=%d, noinfarchcheck=%d\n", solv->dosplitprovides, solv->noupdateprovide, solv->noinfarchcheck);
2706   POOL_DEBUG(SOLV_DEBUG_STATS, "allowuninstall=%d, allowdowngrade=%d, allownamechange=%d, allowarchchange=%d, allowvendorchange=%d\n", solv->allowuninstall, solv->allowdowngrade, solv->allownamechange, solv->allowarchchange, solv->allowvendorchange);
2707   POOL_DEBUG(SOLV_DEBUG_STATS, "promoteepoch=%d, forbidselfconflicts=%d\n", pool->promoteepoch, pool->forbidselfconflicts);
2708   POOL_DEBUG(SOLV_DEBUG_STATS, "obsoleteusesprovides=%d, implicitobsoleteusesprovides=%d, obsoleteusescolors=%d\n", pool->obsoleteusesprovides, pool->implicitobsoleteusesprovides, pool->obsoleteusescolors);
2709   POOL_DEBUG(SOLV_DEBUG_STATS, "dontinstallrecommended=%d, addalreadyrecommended=%d\n", solv->dontinstallrecommended, solv->addalreadyrecommended);
2710
2711   /* create whatprovides if not already there */
2712   if (!pool->whatprovides)
2713     pool_createwhatprovides(pool);
2714
2715   /* create obsolete index */
2716   policy_create_obsolete_index(solv);
2717
2718   /* remember job */
2719   queue_free(&solv->job);
2720   queue_init_clone(&solv->job, job);
2721
2722   if (solv->update_targets)
2723     {
2724       queue_free(solv->update_targets);
2725       solv->update_targets = solv_free(solv->update_targets);
2726     }
2727   /*
2728    * create basic rule set of all involved packages
2729    * use addedmap bitmap to make sure we don't create rules twice
2730    */
2731
2732   /* create noobsolete map if needed */
2733   solver_calculate_noobsmap(pool, job, &solv->noobsoletes);
2734
2735   map_init(&addedmap, pool->nsolvables);
2736   MAPSET(&addedmap, SYSTEMSOLVABLE);
2737
2738   map_init(&installcandidatemap, pool->nsolvables);
2739   queue_init(&q);
2740
2741   now = solv_timems(0);
2742   /*
2743    * create rules for all package that could be involved with the solving
2744    * so called: rpm rules
2745    *
2746    */
2747   if (installed)
2748     {
2749       /* check for update/verify jobs as they need to be known early */
2750       for (i = 0; i < job->count; i += 2)
2751         {
2752           how = job->elements[i];
2753           what = job->elements[i + 1];
2754           select = how & SOLVER_SELECTMASK;
2755           switch (how & SOLVER_JOBMASK)
2756             {
2757             case SOLVER_VERIFY:
2758               if (select == SOLVER_SOLVABLE_ALL || (select == SOLVER_SOLVABLE_REPO && installed && what == installed->repoid))
2759                 solv->fixmap_all = 1;
2760               FOR_JOB_SELECT(p, pp, select, what)
2761                 {
2762                   s = pool->solvables + p;
2763                   if (s->repo != installed)
2764                     continue;
2765                   if (!solv->fixmap.size)
2766                     map_grow(&solv->fixmap, installed->end - installed->start);
2767                   MAPSET(&solv->fixmap, p - installed->start);
2768                 }
2769               break;
2770             case SOLVER_UPDATE:
2771               if (select == SOLVER_SOLVABLE_ALL || (select == SOLVER_SOLVABLE_REPO && installed && what == installed->repoid))
2772                 solv->updatemap_all = 1;
2773               else if (select == SOLVER_SOLVABLE_REPO && what != installed->repoid)
2774                 {
2775                   Repo *repo = pool_id2repo(pool, what);
2776                   if (!repo)
2777                     break;
2778                   /* targeted update */
2779                   FOR_REPO_SOLVABLES(repo, p, s)
2780                     add_update_target(solv, p);
2781                 }
2782               else
2783                 {
2784                   int targeted = 1;
2785                   FOR_JOB_SELECT(p, pp, select, what)
2786                     {
2787                       s = pool->solvables + p;
2788                       if (s->repo != installed)
2789                         continue;
2790                       if (!solv->updatemap.size)
2791                         map_grow(&solv->updatemap, installed->end - installed->start);
2792                       MAPSET(&solv->updatemap, p - installed->start);
2793                       targeted = 0;
2794                     }
2795                   if (targeted)
2796                     {
2797                       FOR_JOB_SELECT(p, pp, select, what)
2798                         add_update_target(solv, p);
2799                     }
2800                 }
2801               break;
2802             default:
2803               break;
2804             }
2805         }
2806
2807       if (solv->update_targets)
2808         transform_update_targets(solv);
2809
2810       oldnrules = solv->nrules;
2811       FOR_REPO_SOLVABLES(installed, p, s)
2812         solver_addrpmrulesforsolvable(solv, s, &addedmap);
2813       POOL_DEBUG(SOLV_DEBUG_STATS, "added %d rpm rules for installed solvables\n", solv->nrules - oldnrules);
2814       oldnrules = solv->nrules;
2815       FOR_REPO_SOLVABLES(installed, p, s)
2816         solver_addrpmrulesforupdaters(solv, s, &addedmap, 1);
2817       POOL_DEBUG(SOLV_DEBUG_STATS, "added %d rpm rules for updaters of installed solvables\n", solv->nrules - oldnrules);
2818     }
2819
2820   /*
2821    * create rules for all packages involved in the job
2822    * (to be installed or removed)
2823    */
2824
2825   oldnrules = solv->nrules;
2826   for (i = 0; i < job->count; i += 2)
2827     {
2828       how = job->elements[i];
2829       what = job->elements[i + 1];
2830       select = how & SOLVER_SELECTMASK;
2831
2832       switch (how & SOLVER_JOBMASK)
2833         {
2834         case SOLVER_INSTALL:
2835           FOR_JOB_SELECT(p, pp, select, what)
2836             {
2837               MAPSET(&installcandidatemap, p);
2838               solver_addrpmrulesforsolvable(solv, pool->solvables + p, &addedmap);
2839             }
2840           break;
2841         case SOLVER_DISTUPGRADE:
2842           if (select == SOLVER_SOLVABLE_ALL)
2843             {
2844               solv->dupmap_all = 1;
2845               solv->updatemap_all = 1;
2846             }
2847           if (!solv->dupmap_all)
2848             hasdupjob = 1;
2849           break;
2850         default:
2851           break;
2852         }
2853     }
2854   POOL_DEBUG(SOLV_DEBUG_STATS, "added %d rpm rules for packages involved in a job\n", solv->nrules - oldnrules);
2855
2856
2857   /*
2858    * add rules for suggests, enhances
2859    */
2860   oldnrules = solv->nrules;
2861   solver_addrpmrulesforweak(solv, &addedmap);
2862   POOL_DEBUG(SOLV_DEBUG_STATS, "added %d rpm rules because of weak dependencies\n", solv->nrules - oldnrules);
2863
2864   /*
2865    * first pass done, we now have all the rpm rules we need.
2866    * unify existing rules before going over all job rules and
2867    * policy rules.
2868    * at this point the system is always solvable,
2869    * as an empty system (remove all packages) is a valid solution
2870    */
2871
2872   IF_POOLDEBUG (SOLV_DEBUG_STATS)
2873     {
2874       int possible = 0, installable = 0;
2875       for (i = 1; i < pool->nsolvables; i++)
2876         {
2877           if (pool_installable(pool, pool->solvables + i))
2878             installable++;
2879           if (MAPTST(&addedmap, i))
2880             possible++;
2881         }
2882       POOL_DEBUG(SOLV_DEBUG_STATS, "%d of %d installable solvables considered for solving\n", possible, installable);
2883     }
2884
2885   solver_unifyrules(solv);                          /* remove duplicate rpm rules */
2886   solv->rpmrules_end = solv->nrules;              /* mark end of rpm rules */
2887
2888   POOL_DEBUG(SOLV_DEBUG_STATS, "rpm rule memory used: %d K\n", solv->nrules * (int)sizeof(Rule) / 1024);
2889   POOL_DEBUG(SOLV_DEBUG_STATS, "rpm rule creation took %d ms\n", solv_timems(now));
2890
2891   /* create dup maps if needed. We need the maps early to create our
2892    * update rules */
2893   if (hasdupjob)
2894     solver_createdupmaps(solv);
2895
2896   /*
2897    * create feature rules
2898    *
2899    * foreach installed:
2900    *   create assertion (keep installed, if no update available)
2901    *   or
2902    *   create update rule (A|update1(A)|update2(A)|...)
2903    *
2904    * those are used later on to keep a version of the installed packages in
2905    * best effort mode
2906    */
2907
2908   solv->featurerules = solv->nrules;              /* mark start of feature rules */
2909   if (installed)
2910     {
2911       /* foreach possibly installed solvable */
2912       for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
2913         {
2914           if (s->repo != installed)
2915             {
2916               solver_addrule(solv, 0, 0);       /* create dummy rule */
2917               continue;
2918             }
2919           solver_addupdaterule(solv, s, 1);    /* allow s to be updated */
2920         }
2921       /* make sure we accounted for all rules */
2922       assert(solv->nrules - solv->featurerules == installed->end - installed->start);
2923     }
2924   solv->featurerules_end = solv->nrules;
2925
2926     /*
2927      * Add update rules for installed solvables
2928      *
2929      * almost identical to feature rules
2930      * except that downgrades/archchanges/vendorchanges are not allowed
2931      */
2932
2933   solv->updaterules = solv->nrules;
2934
2935   if (installed)
2936     { /* foreach installed solvables */
2937       /* we create all update rules, but disable some later on depending on the job */
2938       for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
2939         {
2940           Rule *sr;
2941
2942           if (s->repo != installed)
2943             {
2944               solver_addrule(solv, 0, 0);       /* create dummy rule */
2945               continue;
2946             }
2947           solver_addupdaterule(solv, s, 0);     /* allowall = 0: downgrades not allowed */
2948           /*
2949            * check for and remove duplicate
2950            */
2951           r = solv->rules + solv->nrules - 1;           /* r: update rule */
2952           sr = r - (installed->end - installed->start); /* sr: feature rule */
2953           /* it's orphaned if there is no feature rule or the feature rule
2954            * consists just of the installed package */
2955           if (!sr->p || (sr->p == i && !sr->d && !sr->w2))
2956             queue_push(&solv->orphaned, i);
2957           if (!r->p)
2958             {
2959               assert(solv->dupmap_all && !sr->p);
2960               continue;
2961             }
2962           if (!solver_samerule(solv, r, sr))
2963             memset(sr, 0, sizeof(*sr));         /* delete unneeded feature rule */
2964           else
2965             solver_disablerule(solv, sr);       /* disable feature rule */
2966         }
2967       /* consistency check: we added a rule for _every_ installed solvable */
2968       assert(solv->nrules - solv->updaterules == installed->end - installed->start);
2969     }
2970   solv->updaterules_end = solv->nrules;
2971
2972
2973   /*
2974    * now add all job rules
2975    */
2976
2977   solv->jobrules = solv->nrules;
2978   if (solv->cleandeps_updatepkgs)
2979     {
2980       queue_free(solv->cleandeps_updatepkgs);
2981       solv->cleandeps_updatepkgs = solv_free(solv->cleandeps_updatepkgs);
2982     }
2983   for (i = 0; i < job->count; i += 2)
2984     {
2985       oldnrules = solv->nrules;
2986
2987       how = job->elements[i];
2988       what = job->elements[i + 1];
2989       weak = how & SOLVER_WEAK;
2990       select = how & SOLVER_SELECTMASK;
2991       switch (how & SOLVER_JOBMASK)
2992         {
2993         case SOLVER_INSTALL:
2994           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sinstall %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
2995           if ((how & SOLVER_CLEANDEPS) != 0 && !solv->cleandepsmap.size && installed)
2996             map_grow(&solv->cleandepsmap, installed->end - installed->start);
2997           if (select == SOLVER_SOLVABLE)
2998             {
2999               p = what;
3000               d = 0;
3001             }
3002           else
3003             {
3004               queue_empty(&q);
3005               FOR_JOB_SELECT(p, pp, select, what)
3006                 queue_push(&q, p);
3007               if (!q.count)
3008                 {
3009                   /* no candidate found, make this an impossible rule */
3010                   queue_push(&q, -SYSTEMSOLVABLE);
3011                 }
3012               p = queue_shift(&q);      /* get first candidate */
3013               d = !q.count ? 0 : pool_queuetowhatprovides(pool, &q);    /* internalize */
3014             }
3015           solver_addjobrule(solv, p, d, i, weak);
3016           break;
3017         case SOLVER_ERASE:
3018           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %s%serase %s\n", weak ? "weak " : "", how & SOLVER_CLEANDEPS ? "clean deps " : "", solver_select2str(pool, select, what));
3019           if ((how & SOLVER_CLEANDEPS) != 0 && !solv->cleandepsmap.size && installed)
3020             map_grow(&solv->cleandepsmap, installed->end - installed->start);
3021           /* specific solvable: by id or by nevra */
3022           name = (select == SOLVER_SOLVABLE || (select == SOLVER_SOLVABLE_NAME && ISRELDEP(what))) ? 0 : -1;
3023           if (select == SOLVER_SOLVABLE_ALL)    /* hmmm ;) */
3024             {
3025               FOR_POOL_SOLVABLES(p)
3026                 solver_addjobrule(solv, -p, 0, i, weak);
3027             }
3028           else if (select == SOLVER_SOLVABLE_REPO)
3029             {
3030               Repo *repo = pool_id2repo(pool, what);
3031               if (repo)
3032                 FOR_REPO_SOLVABLES(repo, p, s)
3033                   solver_addjobrule(solv, -p, 0, i, weak);
3034             }
3035           FOR_JOB_SELECT(p, pp, select, what)
3036             {
3037               s = pool->solvables + p;
3038               if (installed && s->repo == installed)
3039                 name = !name ? s->name : -1;
3040               solver_addjobrule(solv, -p, 0, i, weak);
3041             }
3042           /* special case for "erase a specific solvable": we also
3043            * erase all other solvables with that name, so that they
3044            * don't get picked up as replacement.
3045            * name is > 0 if exactly one installed solvable matched.
3046            */
3047           /* XXX: look also at packages that obsolete this package? */
3048           if (name > 0)
3049             {
3050               int j, k;
3051               k = solv->nrules;
3052               FOR_PROVIDES(p, pp, name)
3053                 {
3054                   s = pool->solvables + p;
3055                   if (s->name != name)
3056                     continue;
3057                   /* keep other versions installed */
3058                   if (s->repo == installed)
3059                     continue;
3060                   /* keep installcandidates of other jobs */
3061                   if (MAPTST(&installcandidatemap, p))
3062                     continue;
3063                   /* don't add the same rule twice */
3064                   for (j = oldnrules; j < k; j++)
3065                     if (solv->rules[j].p == -p)
3066                       break;
3067                   if (j == k)
3068                     solver_addjobrule(solv, -p, 0, i, weak);    /* remove by id */
3069                 }
3070             }
3071           break;
3072
3073         case SOLVER_UPDATE:
3074           if ((how & SOLVER_CLEANDEPS) != 0 && installed)
3075             {
3076               if (how == SOLVER_SOLVABLE_ALL || (how == SOLVER_SOLVABLE_REPO && what == installed->repoid))
3077                 {
3078                   FOR_REPO_SOLVABLES(installed, p, s)
3079                     {
3080                       if (!solv->cleandeps_updatepkgs)
3081                         {
3082                           solv->cleandeps_updatepkgs = solv_calloc(1, sizeof(Queue));
3083                           queue_init(solv->cleandeps_updatepkgs);
3084                         }
3085                       queue_pushunique(solv->cleandeps_updatepkgs, p);
3086                       if (!solv->cleandepsmap.size)
3087                         map_grow(&solv->cleandepsmap, installed->end - installed->start);
3088                     }
3089                 }
3090               FOR_JOB_SELECT(p, pp, select, what)
3091                 {
3092                   s = pool->solvables + p;
3093                   if (s->repo != installed)
3094                     continue;
3095                   if (!solv->cleandeps_updatepkgs)
3096                     {
3097                       solv->cleandeps_updatepkgs = solv_calloc(1, sizeof(Queue));
3098                       queue_init(solv->cleandeps_updatepkgs);
3099                     }
3100                   queue_pushunique(solv->cleandeps_updatepkgs, p);
3101                   if (!solv->cleandepsmap.size)
3102                     map_grow(&solv->cleandepsmap, installed->end - installed->start);
3103                 }
3104             }
3105           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %supdate %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
3106           break;
3107         case SOLVER_VERIFY:
3108           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sverify %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
3109           break;
3110         case SOLVER_WEAKENDEPS:
3111           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sweaken deps %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
3112           if (select != SOLVER_SOLVABLE)
3113             break;
3114           s = pool->solvables + what;
3115           weaken_solvable_deps(solv, what);
3116           break;
3117         case SOLVER_NOOBSOLETES:
3118           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sno obsolete %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
3119           break;
3120         case SOLVER_LOCK:
3121           POOL_DEBUG(SOLV_DEBUG_JOB, "job: %slock %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
3122           if (select == SOLVER_SOLVABLE_ALL)
3123             {
3124               FOR_POOL_SOLVABLES(p)
3125                 solver_addjobrule(solv, installed && pool->solvables[p].repo == installed ? p : -p, 0, i, weak);
3126             }
3127           else if (select == SOLVER_SOLVABLE_REPO)
3128             {
3129               Repo *repo = pool_id2repo(pool, what);
3130               if (repo)
3131                 FOR_REPO_SOLVABLES(repo, p, s)
3132                   solver_addjobrule(solv, installed && pool->solvables[p].repo == installed ? p : -p, 0, i, weak);
3133             }
3134           FOR_JOB_SELECT(p, pp, select, what)
3135             solver_addjobrule(solv, installed && pool->solvables[p].repo == installed ? p : -p, 0, i, weak);
3136           break;
3137         case SOLVER_DISTUPGRADE:
3138           POOL_DEBUG(SOLV_DEBUG_JOB, "job: distupgrade %s\n", solver_select2str(pool, select, what));
3139           break;
3140         case SOLVER_DROP_ORPHANED:
3141           POOL_DEBUG(SOLV_DEBUG_JOB, "job: drop orphaned %s\n", solver_select2str(pool, select, what));
3142           if (select == SOLVER_SOLVABLE_ALL || (select == SOLVER_SOLVABLE_REPO && installed && what == installed->repoid))
3143             solv->droporphanedmap_all = 1;
3144           FOR_JOB_SELECT(p, pp, select, what)
3145             {
3146               s = pool->solvables + p;
3147               if (!installed || s->repo != installed)
3148                 continue;
3149               if (!solv->droporphanedmap.size)
3150                 map_grow(&solv->droporphanedmap, installed->end - installed->start);
3151               MAPSET(&solv->droporphanedmap, p - installed->start);
3152             }
3153           break;
3154         case SOLVER_USERINSTALLED:
3155           POOL_DEBUG(SOLV_DEBUG_JOB, "job: user installed %s\n", solver_select2str(pool, select, what));
3156           break;
3157         default:
3158           POOL_DEBUG(SOLV_DEBUG_JOB, "job: unknown job\n");
3159           break;
3160         }
3161
3162         /*
3163          * debug
3164          */
3165
3166       IF_POOLDEBUG (SOLV_DEBUG_JOB)
3167         {
3168           int j;
3169           if (solv->nrules == oldnrules)
3170             POOL_DEBUG(SOLV_DEBUG_JOB, " - no rule created\n");
3171           for (j = oldnrules; j < solv->nrules; j++)
3172             {
3173               POOL_DEBUG(SOLV_DEBUG_JOB, " - job ");
3174               solver_printrule(solv, SOLV_DEBUG_JOB, solv->rules + j);
3175             }
3176         }
3177     }
3178   assert(solv->ruletojob.count == solv->nrules - solv->jobrules);
3179   solv->jobrules_end = solv->nrules;
3180
3181   /* now create infarch and dup rules */
3182   if (!solv->noinfarchcheck)
3183     {
3184       solver_addinfarchrules(solv, &addedmap);
3185       if (pool->obsoleteusescolors)
3186         {
3187           /* currently doesn't work well with infarch rules, so make
3188            * them weak */
3189           for (i = solv->infarchrules; i < solv->infarchrules_end; i++)
3190             queue_push(&solv->weakruleq, i);
3191         }
3192     }
3193   else
3194     solv->infarchrules = solv->infarchrules_end = solv->nrules;
3195
3196   if (hasdupjob)
3197     {
3198       solver_addduprules(solv, &addedmap);
3199       solver_freedupmaps(solv); /* no longer needed */
3200     }
3201   else
3202     solv->duprules = solv->duprules_end = solv->nrules;
3203
3204   if (1)
3205     solver_addchoicerules(solv);
3206   else
3207     solv->choicerules = solv->choicerules_end = solv->nrules;
3208
3209   /* all rules created
3210    * --------------------------------------------------------------
3211    * prepare for solving
3212    */
3213
3214   /* free unneeded memory */
3215   map_free(&addedmap);
3216   map_free(&installcandidatemap);
3217   queue_free(&q);
3218
3219   POOL_DEBUG(SOLV_DEBUG_STATS, "%d rpm rules, 2 * %d update rules, %d job rules, %d infarch rules, %d dup rules, %d choice rules\n", solv->rpmrules_end - 1, solv->updaterules_end - solv->updaterules, solv->jobrules_end - solv->jobrules, solv->infarchrules_end - solv->infarchrules, solv->duprules_end - solv->duprules, solv->choicerules_end - solv->choicerules);
3220   POOL_DEBUG(SOLV_DEBUG_STATS, "overall rule memory used: %d K\n", solv->nrules * (int)sizeof(Rule) / 1024);
3221
3222   /* create weak map */
3223   map_init(&solv->weakrulemap, solv->nrules);
3224   for (i = 0; i < solv->weakruleq.count; i++)
3225     {
3226       p = solv->weakruleq.elements[i];
3227       MAPSET(&solv->weakrulemap, p);
3228     }
3229
3230   /* all new rules are learnt after this point */
3231   solv->learntrules = solv->nrules;
3232
3233   /* create watches chains */
3234   makewatches(solv);
3235
3236   /* create assertion index. it is only used to speed up
3237    * makeruledecsions() a bit */
3238   for (i = 1, r = solv->rules + i; i < solv->nrules; i++, r++)
3239     if (r->p && !r->w2 && (r->d == 0 || r->d == -1))
3240       queue_push(&solv->ruleassertions, i);
3241
3242   /* disable update rules that conflict with our job */
3243   solver_disablepolicyrules(solv);
3244
3245   /* make initial decisions based on assertion rules */
3246   makeruledecisions(solv);
3247   POOL_DEBUG(SOLV_DEBUG_SOLVER, "problems so far: %d\n", solv->problems.count);
3248
3249   /* no mistakes */
3250   if (solv->cleandeps_mistakes)
3251     {
3252       queue_free(solv->cleandeps_mistakes);
3253       solv->cleandeps_mistakes = solv_free(solv->cleandeps_mistakes);
3254     }
3255
3256   /*
3257    * ********************************************
3258    * solve!
3259    * ********************************************
3260    */
3261
3262   now = solv_timems(0);
3263   solver_run_sat(solv, 1, solv->dontinstallrecommended ? 0 : 1);
3264   POOL_DEBUG(SOLV_DEBUG_STATS, "solver took %d ms\n", solv_timems(now));
3265
3266   /*
3267    * prepare solution queue if there were problems
3268    */
3269   solver_prepare_solutions(solv);
3270
3271   POOL_DEBUG(SOLV_DEBUG_STATS, "final solver statistics: %d problems, %d learned rules, %d unsolvable\n", solv->problems.count / 2, solv->stats_learned, solv->stats_unsolvable);
3272   POOL_DEBUG(SOLV_DEBUG_STATS, "solver_solve took %d ms\n", solv_timems(solve_start));
3273
3274   /* return number of problems */
3275   return solv->problems.count ? solv->problems.count / 2 : 0;
3276 }
3277
3278 Transaction *
3279 solver_create_transaction(Solver *solv)
3280 {
3281   return transaction_create_decisionq(solv->pool, &solv->decisionq, &solv->noobsoletes);
3282 }
3283
3284 void solver_get_orphaned(Solver *solv, Queue *orphanedq)
3285 {
3286   queue_free(orphanedq);
3287   queue_init_clone(orphanedq, &solv->orphaned);
3288 }
3289
3290 void solver_get_recommendations(Solver *solv, Queue *recommendationsq, Queue *suggestionsq, int noselected)
3291 {
3292   Pool *pool = solv->pool;
3293   Queue redoq, disabledq;
3294   int goterase, i;
3295   Solvable *s;
3296   Rule *r;
3297   Map obsmap;
3298
3299   if (!recommendationsq && !suggestionsq)
3300     return;
3301
3302   map_init(&obsmap, pool->nsolvables);
3303   if (solv->installed)
3304     {
3305       Id obs, *obsp, p, po, ppo;
3306       for (p = solv->installed->start; p < solv->installed->end; p++)
3307         {
3308           s = pool->solvables + p;
3309           if (s->repo != solv->installed || !s->obsoletes)
3310             continue;
3311           if (solv->decisionmap[p] <= 0)
3312             continue;
3313           if (solv->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
3314             continue;
3315           obsp = s->repo->idarraydata + s->obsoletes;
3316           /* foreach obsoletes */
3317           while ((obs = *obsp++) != 0)
3318             FOR_PROVIDES(po, ppo, obs)
3319               MAPSET(&obsmap, po);
3320         }
3321     }
3322
3323   queue_init(&redoq);
3324   queue_init(&disabledq);
3325   goterase = 0;
3326   /* disable all erase jobs (including weak "keep uninstalled" rules) */
3327   for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
3328     {
3329       if (r->d < 0)     /* disabled ? */
3330         continue;
3331       if (r->p >= 0)    /* install job? */
3332         continue;
3333       queue_push(&disabledq, i);
3334       solver_disablerule(solv, r);
3335       goterase++;
3336     }
3337
3338   if (goterase)
3339     {
3340       enabledisablelearntrules(solv);
3341       removedisabledconflicts(solv, &redoq);
3342     }
3343
3344   /*
3345    * find recommended packages
3346    */
3347   if (recommendationsq)
3348     {
3349       Id rec, *recp, p, pp;
3350
3351       queue_empty(recommendationsq);
3352       /* create map of all recommened packages */
3353       solv->recommends_index = -1;
3354       MAPZERO(&solv->recommendsmap);
3355
3356       /* put all packages the solver already chose in the map */
3357       if (solv->decisioncnt_weak)
3358         {
3359           for (i = solv->decisioncnt_weak; i < solv->decisioncnt_orphan; i++)
3360             {
3361               Id why;
3362               why = solv->decisionq_why.elements[i];
3363               if (why)
3364                 continue;       /* forced by unit rule */
3365               p = solv->decisionq.elements[i];
3366               if (p < 0)
3367                 continue;
3368               MAPSET(&solv->recommendsmap, p);
3369             }
3370         }
3371
3372       for (i = 0; i < solv->decisionq.count; i++)
3373         {
3374           p = solv->decisionq.elements[i];
3375           if (p < 0)
3376             continue;
3377           s = pool->solvables + p;
3378           if (s->recommends)
3379             {
3380               recp = s->repo->idarraydata + s->recommends;
3381               while ((rec = *recp++) != 0)
3382                 {
3383                   FOR_PROVIDES(p, pp, rec)
3384                     if (solv->decisionmap[p] > 0)
3385                       break;
3386                   if (p)
3387                     {
3388                       if (!noselected)
3389                         {
3390                           FOR_PROVIDES(p, pp, rec)
3391                             if (solv->decisionmap[p] > 0)
3392                               MAPSET(&solv->recommendsmap, p);
3393                         }
3394                       continue; /* p != 0: already fulfilled */
3395                     }
3396                   FOR_PROVIDES(p, pp, rec)
3397                     MAPSET(&solv->recommendsmap, p);
3398                 }
3399             }
3400         }
3401       for (i = 1; i < pool->nsolvables; i++)
3402         {
3403           if (solv->decisionmap[i] < 0)
3404             continue;
3405           if (solv->decisionmap[i] > 0 && noselected)
3406             continue;
3407           if (MAPTST(&obsmap, i))
3408             continue;
3409           s = pool->solvables + i;
3410           if (!MAPTST(&solv->recommendsmap, i))
3411             {
3412               if (!s->supplements)
3413                 continue;
3414               if (!pool_installable(pool, s))
3415                 continue;
3416               if (!solver_is_supplementing(solv, s))
3417                 continue;
3418             }
3419           queue_push(recommendationsq, i);
3420         }
3421       /* we use MODE_SUGGEST here so that repo prio is ignored */
3422       policy_filter_unwanted(solv, recommendationsq, POLICY_MODE_SUGGEST);
3423     }
3424
3425   /*
3426    * find suggested packages
3427    */
3428
3429   if (suggestionsq)
3430     {
3431       Id sug, *sugp, p, pp;
3432
3433       queue_empty(suggestionsq);
3434       /* create map of all suggests that are still open */
3435       solv->recommends_index = -1;
3436       MAPZERO(&solv->suggestsmap);
3437       for (i = 0; i < solv->decisionq.count; i++)
3438         {
3439           p = solv->decisionq.elements[i];
3440           if (p < 0)
3441             continue;
3442           s = pool->solvables + p;
3443           if (s->suggests)
3444             {
3445               sugp = s->repo->idarraydata + s->suggests;
3446               while ((sug = *sugp++) != 0)
3447                 {
3448                   FOR_PROVIDES(p, pp, sug)
3449                     if (solv->decisionmap[p] > 0)
3450                       break;
3451                   if (p)
3452                     {
3453                       if (!noselected)
3454                         {
3455                           FOR_PROVIDES(p, pp, sug)
3456                             if (solv->decisionmap[p] > 0)
3457                               MAPSET(&solv->suggestsmap, p);
3458                         }
3459                       continue; /* already fulfilled */
3460                     }
3461                   FOR_PROVIDES(p, pp, sug)
3462                     MAPSET(&solv->suggestsmap, p);
3463                 }
3464             }
3465         }
3466       for (i = 1; i < pool->nsolvables; i++)
3467         {
3468           if (solv->decisionmap[i] < 0)
3469             continue;
3470           if (solv->decisionmap[i] > 0 && noselected)
3471             continue;
3472           if (MAPTST(&obsmap, i))
3473             continue;
3474           s = pool->solvables + i;
3475           if (!MAPTST(&solv->suggestsmap, i))
3476             {
3477               if (!s->enhances)
3478                 continue;
3479               if (!pool_installable(pool, s))
3480                 continue;
3481               if (!solver_is_enhancing(solv, s))
3482                 continue;
3483             }
3484           queue_push(suggestionsq, i);
3485         }
3486       policy_filter_unwanted(solv, suggestionsq, POLICY_MODE_SUGGEST);
3487     }
3488
3489   /* undo removedisabledconflicts */
3490   if (redoq.count)
3491     undo_removedisabledconflicts(solv, &redoq);
3492   queue_free(&redoq);
3493
3494   /* undo job rule disabling */
3495   for (i = 0; i < disabledq.count; i++)
3496     solver_enablerule(solv, solv->rules + disabledq.elements[i]);
3497   queue_free(&disabledq);
3498   map_free(&obsmap);
3499 }
3500
3501
3502 /***********************************************************************/
3503 /* disk usage computations */
3504
3505 /*-------------------------------------------------------------------
3506  *
3507  * calculate DU changes
3508  */
3509
3510 void
3511 solver_calc_duchanges(Solver *solv, DUChanges *mps, int nmps)
3512 {
3513   Map installedmap;
3514
3515   solver_create_state_maps(solv, &installedmap, 0);
3516   pool_calc_duchanges(solv->pool, &installedmap, mps, nmps);
3517   map_free(&installedmap);
3518 }
3519
3520
3521 /*-------------------------------------------------------------------
3522  *
3523  * calculate changes in install size
3524  */
3525
3526 int
3527 solver_calc_installsizechange(Solver *solv)
3528 {
3529   Map installedmap;
3530   int change;
3531
3532   solver_create_state_maps(solv, &installedmap, 0);
3533   change = pool_calc_installsizechange(solv->pool, &installedmap);
3534   map_free(&installedmap);
3535   return change;
3536 }
3537
3538 void
3539 solver_create_state_maps(Solver *solv, Map *installedmap, Map *conflictsmap)
3540 {
3541   pool_create_state_maps(solv->pool, &solv->decisionq, installedmap, conflictsmap);
3542 }
3543
3544 void
3545 solver_trivial_installable(Solver *solv, Queue *pkgs, Queue *res)
3546 {
3547   Map installedmap;
3548   pool_create_state_maps(solv->pool,  &solv->decisionq, &installedmap, 0);
3549   pool_trivial_installable_noobsoletesmap(solv->pool, &installedmap, pkgs, res, solv->noobsoletes.size ? &solv->noobsoletes : 0);
3550   map_free(&installedmap);
3551 }
3552
3553 /*-------------------------------------------------------------------
3554  *
3555  * decision introspection
3556  */
3557
3558 int
3559 solver_get_decisionlevel(Solver *solv, Id p)
3560 {
3561   return solv->decisionmap[p];
3562 }
3563
3564 void
3565 solver_get_decisionqueue(Solver *solv, Queue *decisionq)
3566 {
3567   queue_free(decisionq);
3568   queue_init_clone(decisionq, &solv->decisionq);
3569 }
3570
3571 int
3572 solver_get_lastdecisionblocklevel(Solver *solv)
3573 {
3574   Id p;
3575   if (solv->decisionq.count == 0)
3576     return 0;
3577   p = solv->decisionq.elements[solv->decisionq.count - 1];
3578   if (p < 0)
3579     p = -p;
3580   return solv->decisionmap[p] < 0 ? -solv->decisionmap[p] : solv->decisionmap[p];
3581 }
3582
3583 void
3584 solver_get_decisionblock(Solver *solv, int level, Queue *decisionq)
3585 {
3586   Id p;
3587   int i;
3588
3589   queue_empty(decisionq);
3590   for (i = 0; i < solv->decisionq.count; i++)
3591     {
3592       p = solv->decisionq.elements[i];
3593       if (p < 0)
3594         p = -p;
3595       if (solv->decisionmap[p] == level || solv->decisionmap[p] == -level)
3596         break;
3597     }
3598   if (i == solv->decisionq.count)
3599     return;
3600   for (i = 0; i < solv->decisionq.count; i++)
3601     {
3602       p = solv->decisionq.elements[i];
3603       if (p < 0)
3604         p = -p;
3605       if (solv->decisionmap[p] == level || solv->decisionmap[p] == -level)
3606         queue_push(decisionq, p);
3607       else
3608         break;
3609     }
3610 }
3611
3612 int
3613 solver_describe_decision(Solver *solv, Id p, Id *infop)
3614 {
3615   int i;
3616   Id pp, why;
3617
3618   if (infop)
3619     *infop = 0;
3620   if (!solv->decisionmap[p])
3621     return SOLVER_REASON_UNRELATED;
3622   pp = solv->decisionmap[p] < 0 ? -p : p;
3623   for (i = 0; i < solv->decisionq.count; i++)
3624     if (solv->decisionq.elements[i] == pp)
3625       break;
3626   if (i == solv->decisionq.count)       /* just in case... */
3627     return SOLVER_REASON_UNRELATED;
3628   why = solv->decisionq_why.elements[i];
3629   if (why > 0)
3630     {
3631       if (infop)
3632         *infop = why;
3633       return SOLVER_REASON_UNIT_RULE;
3634     }
3635   why = -why;
3636   if (i < solv->decisioncnt_update)
3637     {
3638       if (i == 0)
3639         {
3640           if (infop)
3641             *infop = SYSTEMSOLVABLE;
3642           return SOLVER_REASON_KEEP_INSTALLED;
3643         }
3644       if (infop)
3645         *infop = why;
3646       return SOLVER_REASON_RESOLVE_JOB;
3647     }
3648   if (i < solv->decisioncnt_keep)
3649     {
3650       if (why == 0 && pp < 0)
3651         return SOLVER_REASON_CLEANDEPS_ERASE;
3652       if (infop)
3653         {
3654           if (why >= solv->updaterules && why < solv->updaterules_end)
3655             *infop = why - solv->updaterules;
3656           else if (why >= solv->featurerules && why < solv->featurerules_end)
3657             *infop = why - solv->featurerules;
3658         }
3659       return SOLVER_REASON_UPDATE_INSTALLED;
3660     }
3661   if (i < solv->decisioncnt_resolve)
3662     {
3663       if (why == 0 && pp < 0)
3664         return SOLVER_REASON_CLEANDEPS_ERASE;
3665       if (infop)
3666         {
3667           if (why >= solv->updaterules && why < solv->updaterules_end)
3668             *infop = why - solv->updaterules;
3669           else if (why >= solv->featurerules && why < solv->featurerules_end)
3670             *infop = why - solv->featurerules;
3671         }
3672       return SOLVER_REASON_KEEP_INSTALLED;
3673     }
3674   if (i < solv->decisioncnt_weak)
3675     {
3676       if (infop)
3677         *infop = why;
3678       return SOLVER_REASON_RESOLVE;
3679     }
3680   if (solv->decisionq.count < solv->decisioncnt_orphan)
3681     return SOLVER_REASON_WEAKDEP;
3682   return SOLVER_REASON_RESOLVE_ORPHAN;
3683 }
3684
3685
3686 void
3687 solver_describe_weakdep_decision(Solver *solv, Id p, Queue *whyq)
3688 {
3689   Pool *pool = solv->pool;
3690   int i;
3691   int level = solv->decisionmap[p];
3692   int decisionno;
3693   Solvable *s;
3694
3695   queue_empty(whyq);
3696   if (level < 0)
3697     return;     /* huh? */
3698   for (decisionno = 0; decisionno < solv->decisionq.count; decisionno++)
3699     if (solv->decisionq.elements[decisionno] == p)
3700       break;
3701   if (decisionno == solv->decisionq.count)
3702     return;     /* huh? */
3703   if (decisionno < solv->decisioncnt_weak || decisionno >= solv->decisioncnt_orphan)
3704     return;     /* huh? */
3705
3706   /* 1) list all packages that recommend us */
3707   for (i = 1; i < pool->nsolvables; i++)
3708     {
3709       Id *recp, rec, pp2, p2;
3710       if (solv->decisionmap[i] < 0 || solv->decisionmap[i] >= level)
3711         continue;
3712       s = pool->solvables + i;
3713       if (!s->recommends)
3714         continue;
3715       if (!solv->addalreadyrecommended && s->repo == solv->installed)
3716         continue;
3717       recp = s->repo->idarraydata + s->recommends;
3718       while ((rec = *recp++) != 0)
3719         {
3720           int found = 0;
3721           FOR_PROVIDES(p2, pp2, rec)
3722             {
3723               if (p2 == p)
3724                 found = 1;
3725               else
3726                 {
3727                   /* if p2 is already installed, this recommends is ignored */
3728                   if (solv->decisionmap[p2] > 0 && solv->decisionmap[p2] < level)
3729                     break;
3730                 }
3731             }
3732           if (!p2 && found)
3733             {
3734               queue_push(whyq, SOLVER_REASON_RECOMMENDED);
3735               queue_push2(whyq, p2, rec);
3736             }
3737         }
3738     }
3739   /* 2) list all supplements */
3740   s = pool->solvables + p;
3741   if (s->supplements && level > 0)
3742     {
3743       Id *supp, sup, pp2, p2;
3744       /* this is a hack. to use solver_dep_fulfilled we temporarily clear
3745        * everything above our level in the decisionmap */
3746       for (i = decisionno; i < solv->decisionq.count; i++ )
3747         {
3748           p2 = solv->decisionq.elements[i];
3749           if (p2 > 0)
3750             solv->decisionmap[p2] = -solv->decisionmap[p2];
3751         }
3752       supp = s->repo->idarraydata + s->supplements;
3753       while ((sup = *supp++) != 0)
3754         if (solver_dep_fulfilled(solv, sup))
3755           {
3756             int found = 0;
3757             /* let's see if this is an easy supp */
3758             FOR_PROVIDES(p2, pp2, sup)
3759               {
3760                 if (!solv->addalreadyrecommended && solv->installed)
3761                   {
3762                     if (pool->solvables[p2].repo == solv->installed)
3763                       continue;
3764                   }
3765                 if (solv->decisionmap[p2] > 0 && solv->decisionmap[p2] < level)
3766                   {
3767                     queue_push(whyq, SOLVER_REASON_SUPPLEMENTED);
3768                     queue_push2(whyq, p2, sup);
3769                     found = 1;
3770                   }
3771               }
3772             if (!found)
3773               {
3774                 /* hard case, just note dependency with no package */
3775                 queue_push(whyq, SOLVER_REASON_SUPPLEMENTED);
3776                 queue_push2(whyq, 0, sup);
3777               }
3778           }
3779       for (i = decisionno; i < solv->decisionq.count; i++)
3780         {
3781           p2 = solv->decisionq.elements[i];
3782           if (p2 > 0)
3783             solv->decisionmap[p2] = -solv->decisionmap[p2];
3784         }
3785     }
3786 }
3787
3788 void
3789 pool_job2solvables(Pool *pool, Queue *pkgs, Id how, Id what)
3790 {
3791   Id p, pp;
3792   how &= SOLVER_SELECTMASK;
3793   queue_empty(pkgs);
3794   if (how == SOLVER_SOLVABLE_ALL)
3795     {
3796       FOR_POOL_SOLVABLES(p)
3797         queue_push(pkgs, p);
3798     }
3799   else if (how == SOLVER_SOLVABLE_REPO)
3800     {
3801       Repo *repo = pool_id2repo(pool, what);
3802       Solvable *s;
3803       if (repo)
3804         FOR_REPO_SOLVABLES(repo, p, s)
3805           queue_push(pkgs, p);
3806     }
3807   else
3808     {
3809       FOR_JOB_SELECT(p, pp, how, what)
3810         queue_push(pkgs, p);
3811     }
3812 }
3813
3814 int
3815 pool_isemptyupdatejob(Pool *pool, Id how, Id what)
3816 {
3817   Id p, pp, pi, pip;
3818   Id select = how & SOLVER_SELECTMASK;
3819   if ((how & SOLVER_JOBMASK) != SOLVER_UPDATE)
3820     return 0;
3821   if (select == SOLVER_SOLVABLE_ALL || select == SOLVER_SOLVABLE_REPO)
3822     return 0;
3823   if (!pool->installed)
3824     return 1;
3825   FOR_JOB_SELECT(p, pp, select, what)
3826     if (pool->solvables[p].repo == pool->installed)
3827       return 0;
3828   /* hard work */
3829   FOR_JOB_SELECT(p, pp, select, what)
3830     {
3831       Solvable *s = pool->solvables + p;
3832       FOR_PROVIDES(pi, pip, s->name)
3833         if (pool->solvables[pi].name == s->name && pool->solvables[pi].repo == pool->installed)
3834           return 0;
3835       if (s->obsoletes)
3836         {
3837           Id obs, *obsp = s->repo->idarraydata + s->obsoletes;
3838           while ((obs = *obsp++) != 0)
3839             {
3840               FOR_PROVIDES(pi, pip, obs)
3841                 {
3842                   Solvable *si = pool->solvables + pi;
3843                   if (si->repo != pool->installed)
3844                     continue;
3845                   if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, si, obs))
3846                     continue;
3847                   if (pool->obsoleteusescolors && !pool_colormatch(pool, s, si))
3848                     continue;
3849                   return 0;
3850                 }
3851             }
3852         }
3853     }
3854   return 1;
3855 }