[platform/upstream/libsolv.git] / src / solver.c

/*
 * Copyright (c) 2007-2008, Novell Inc.
 *
 * This program is licensed under the BSD license, read LICENSE.BSD
 * for further information
 */

/*
 * solver.c
 *
 * SAT based dependency solver
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>

#include "solver.h"
#include "solver_private.h"
#include "bitmap.h"
#include "pool.h"
#include "util.h"
#include "policy.h"
#include "poolarch.h"
#include "solverdebug.h"
#include "cplxdeps.h"
#include "linkedpkg.h"

#define RULES_BLOCK 63


/************************************************************************/

/*
 * enable/disable learnt rules
 *
 * we have enabled or disabled some of our rules. We now reenable all
 * of our learnt rules except the ones that were learnt from rules that
 * are now disabled.
 */
static void
enabledisablelearntrules(Solver *solv)
{
  Pool *pool = solv->pool;
  Rule *r;
  Id why, *whyp;
  int i;

  POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "enabledisablelearntrules called\n");
  for (i = solv->learntrules, r = solv->rules + i; i < solv->nrules; i++, r++)
    {
      whyp = solv->learnt_pool.elements + solv->learnt_why.elements[i - solv->learntrules];
      while ((why = *whyp++) != 0)
        {
          assert(why > 0 && why < i);
          if (solv->rules[why].d < 0)
            break;
        }
      /* why != 0: we found a disabled rule, disable the learnt rule */
      if (why && r->d >= 0)
        {
          IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
            {
              POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "disabling ");
              solver_printruleclass(solv, SOLV_DEBUG_SOLUTIONS, r);
            }
          solver_disablerule(solv, r);
        }
      else if (!why && r->d < 0)
        {
          IF_POOLDEBUG (SOLV_DEBUG_SOLUTIONS)
            {
              POOL_DEBUG(SOLV_DEBUG_SOLUTIONS, "re-enabling ");
              solver_printruleclass(solv, SOLV_DEBUG_SOLUTIONS, r);
            }
          solver_enablerule(solv, r);
        }
    }
}


/*
 * make assertion rules into decisions
 *
 * Go through rules and add direct assertions to the decisionqueue.
 * If we find a conflict, disable rules and add them to problem queue.
 */

static int
makeruledecisions(Solver *solv, int disablerules)
{
  Pool *pool = solv->pool;
  int i, ri, ii, ori;
  Rule *r, *rr;
  Id v, vv;
  int decisionstart;
  int record_proof = 1;
  int oldproblemcount;
  int havedisabled = 0;
  int doautouninstall;

  /* The system solvable is always installed first */
  assert(solv->decisionq.count == 0);
  queue_push(&solv->decisionq, SYSTEMSOLVABLE);
  queue_push(&solv->decisionq_why, 0);
  queue_push2(&solv->decisionq_reason, 0, 0);
  solv->decisionmap[SYSTEMSOLVABLE] = 1;        /* installed at level '1' */

  decisionstart = solv->decisionq.count;
  for (;;)
    {
      /* if we needed to re-run, back up decisions to decisionstart */
      while (solv->decisionq.count > decisionstart)
        {
          v = solv->decisionq.elements[--solv->decisionq.count];
          --solv->decisionq_why.count;
          vv = v > 0 ? v : -v;
          solv->decisionmap[vv] = 0;
        }

      /* note that the ruleassertions queue is ordered */
      for (ii = 0; ii < solv->ruleassertions.count; ii++)
        {
          ri = solv->ruleassertions.elements[ii];
          r = solv->rules + ri;

          if (havedisabled && ri >= solv->learntrules)
            {
              /* just started with learnt rule assertions. If we have disabled
               * some rules, adapt the learnt rule status */
              enabledisablelearntrules(solv);
              havedisabled = 0;
            }

          if (r->d < 0 || !r->p || r->w2)       /* disabled, dummy or no assertion */
            continue;

          /* do weak rules in phase 2 */
          if (ri < solv->learntrules && solv->weakrulemap.size && MAPTST(&solv->weakrulemap, ri))
            continue;

          v = r->p;
          vv = v > 0 ? v : -v;

          if (!solv->decisionmap[vv])          /* if not yet decided */
            {
              queue_push(&solv->decisionq, v);
              queue_push(&solv->decisionq_why, ri);
              solv->decisionmap[vv] = v > 0 ? 1 : -1;
              IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
                {
                  Solvable *s = solv->pool->solvables + vv;
                  if (v < 0)
                    POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "conflicting %s (assertion)\n", pool_solvable2str(solv->pool, s));
                  else
                    POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "installing  %s (assertion)\n", pool_solvable2str(solv->pool, s));
                }
              continue;
            }

          /* check against previous decision: is there a conflict? */
          if (v > 0 && solv->decisionmap[vv] > 0)    /* ok to install */
            continue;
          if (v < 0 && solv->decisionmap[vv] < 0)    /* ok to remove */
            continue;

          /*
           * found a conflict!
           *
           * The rule (r) we're currently processing says something
           * different (v = r->p) than a previous decision (decisionmap[abs(v)])
           * on this literal
           */

          if (ri >= solv->learntrules)
            {
              /* conflict with a learnt rule */
              /* can happen when packages cannot be installed for multiple reasons. */
              /* we disable the learnt rule in this case */
              /* (XXX: we should really do something like analyze_unsolvable_rule here!) */
              solver_disablerule(solv, r);
              continue;
            }

          POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "ANALYZE UNSOLVABLE ASSERTION ----------------------\n");
          assert(ri >= solv->pkgrules_end);     /* must not have a conflict in the pkg rules! */

          /*
           * find the decision which is the "opposite" of the rule
           */
          for (i = 0; i < solv->decisionq.count; i++)
            if (solv->decisionq.elements[i] == -v)
              break;
          assert(i < solv->decisionq.count);         /* assert that we found it */
          if (v == -SYSTEMSOLVABLE)
            ori = 0;
          else
            {
              ori = solv->decisionq_why.elements[i];            /* the conflicting rule */
              assert(ori > 0);
            }

          /*
           * record the problem
           */
          doautouninstall = 0;
          oldproblemcount = solv->problems.count;
          queue_push(&solv->problems, 0);                       /* start problem */
          if (ori < solv->pkgrules_end)
            {
              /* easy: conflict with system solvable or pkg rule */
              assert(v > 0 || v == -SYSTEMSOLVABLE);
              IF_POOLDEBUG (SOLV_DEBUG_UNSOLVABLE)
                {
                  if (ori)
                    POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "conflict with pkg rule, disabling rule #%d\n", ri);
                  else
                    POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "conflict with system solvable, disabling rule #%d\n", ri);
                  solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + ri);
                  if (ori)
                    solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + ori);
                }
              solver_recordproblem(solv, ri);
              if (ri >= solv->featurerules && ri < solv->updaterules_end)
                doautouninstall = 1;
            }
          else
            {
              POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "conflicting update/job assertions over literal %d\n", vv);
              /*
               * push all of our rules (can only be feature or job rules)
               * asserting this literal on the problem stack
               */
              for (i = solv->pkgrules_end, rr = solv->rules + i; i < solv->learntrules; i++, rr++)
                {
                  if (rr->d < 0                          /* disabled */
                      || rr->w2)                         /*  or no assertion */
                    continue;
                  if (rr->p != vv                        /* not affecting the literal */
                      && rr->p != -vv)
                    continue;
                  if (solv->weakrulemap.size && MAPTST(&solv->weakrulemap, i))     /* weak: silently ignore */
                    continue;

                  POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, " - disabling rule #%d\n", i);
                  solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + i);
                  solver_recordproblem(solv, i);
                  if (i >= solv->featurerules && i < solv->updaterules_end)
                    doautouninstall = 1;
                }
            }
          queue_push(&solv->problems, 0);                       /* finish problem */

          /* try autouninstall if requested */
          if (doautouninstall)
            {
              if (solv->allowuninstall || solv->allowuninstall_all || solv->allowuninstallmap.size)
                if (solver_autouninstall(solv, oldproblemcount) != 0)
                  {
                    solv->problems.count = oldproblemcount;
                    havedisabled = 1;
                    break;      /* start over */
                  }
            }

          /* record the proof if requested */
          if (record_proof)
            {
              solv->problems.elements[oldproblemcount] = solv->learnt_pool.count;
              queue_push(&solv->learnt_pool, ri);
              if (ori)
                queue_push(&solv->learnt_pool, ori);
              queue_push(&solv->learnt_pool, 0);
            }

          if (!disablerules)
            {
              POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "UNSOLVABLE\n");
              return -1;
            }
          /* disable all problem rules */
          solver_disableproblemset(solv, oldproblemcount);
          havedisabled = 1;
          break;        /* start over */
        }
      if (ii < solv->ruleassertions.count)
        continue;

      /*
       * phase 2: now do the weak assertions
       */
      if (!solv->weakrulemap.size)
        break;                          /* no weak rules, no phase 2 */
      for (ii = 0; ii < solv->ruleassertions.count; ii++)
        {
          ri = solv->ruleassertions.elements[ii];
          r = solv->rules + ri;
          if (r->d < 0 || r->w2)                         /* disabled or no assertion */
            continue;
          if (ri >= solv->learntrules || !MAPTST(&solv->weakrulemap, ri))       /* skip non-weak */
            continue;
          v = r->p;
          vv = v > 0 ? v : -v;

          if (!solv->decisionmap[vv])          /* if not yet decided */
            {
              queue_push(&solv->decisionq, v);
              queue_push(&solv->decisionq_why, r - solv->rules);
              solv->decisionmap[vv] = v > 0 ? 1 : -1;
              IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
                {
                  Solvable *s = solv->pool->solvables + vv;
                  if (v < 0)
                    POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "conflicting %s (weak assertion)\n", pool_solvable2str(solv->pool, s));
                  else
                    POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "installing  %s (weak assertion)\n", pool_solvable2str(solv->pool, s));
                }
              continue;
            }
          /* check against previous decision: is there a conflict? */
          if (v > 0 && solv->decisionmap[vv] > 0)
            continue;
          if (v < 0 && solv->decisionmap[vv] < 0)
            continue;

          POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "assertion conflict, but I am weak, disabling ");
          solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, r);
          solver_fixproblem(solv, ri);
          havedisabled = 1;
          break;        /* start over */
        }
      if (ii == solv->ruleassertions.count)
        break;  /* finished! */
    }
  return 1;             /* the new level */
}


/********************************************************************/
/* watches */


/*-------------------------------------------------------------------
 * makewatches
 *
 * initial setup for all watches
 */

static void
makewatches(Solver *solv)
{
  Rule *r;
  int i;
  int nsolvables = solv->pool->nsolvables;

  solv_free(solv->watches);
  /* lower half for removals, upper half for installs */
  solv->watches = solv_calloc(2 * nsolvables, sizeof(Id));
  for (i = 1, r = solv->rules + solv->nrules - 1; i < solv->nrules; i++, r--)
    {
      if (!r->w2)               /* assertions do not need watches */
        continue;

      /* see addwatches_rule(solv, r) */
      r->n1 = solv->watches[nsolvables + r->w1];
      solv->watches[nsolvables + r->w1] = r - solv->rules;

      r->n2 = solv->watches[nsolvables + r->w2];
      solv->watches[nsolvables + r->w2] = r - solv->rules;
    }
}


/*-------------------------------------------------------------------
 *
 * add watches (for a new learned rule)
 * sets up watches for a single rule
 *
 * see also makewatches() above.
 */

static inline void
addwatches_rule(Solver *solv, Rule *r)
{
  int nsolvables = solv->pool->nsolvables;

  r->n1 = solv->watches[nsolvables + r->w1];
  solv->watches[nsolvables + r->w1] = r - solv->rules;

  r->n2 = solv->watches[nsolvables + r->w2];
  solv->watches[nsolvables + r->w2] = r - solv->rules;
}


/********************************************************************/
/*
 * rule propagation
 */


/* shortcuts to check if a literal (positive or negative) assignment
 * evaluates to 'true' or 'false'
 */
#define DECISIONMAP_TRUE(p) ((p) > 0 ? (decisionmap[p] > 0) : (decisionmap[-p] < 0))
#define DECISIONMAP_FALSE(p) ((p) > 0 ? (decisionmap[p] < 0) : (decisionmap[-p] > 0))
#define DECISIONMAP_UNDEF(p) (decisionmap[(p) > 0 ? (p) : -(p)] == 0)

/*-------------------------------------------------------------------
 *
 * propagate
 *
 * make decision and propagate to all rules
 *
 * Evaluate each term affected by the decision (linked through watches).
 * If we find unit rules we make new decisions based on them.
 *
 * return : 0 = everything is OK
 *          rule = conflict found in this rule
 */

static Rule *
propagate(Solver *solv, int level)
{
  Pool *pool = solv->pool;
  Id *rp, *next_rp;           /* rule pointer, next rule pointer in linked list */
  Rule *r;                    /* rule */
  Id p, pkg, other_watch;
  Id *dp;
  Id *decisionmap = solv->decisionmap;
  Id *watches = solv->watches + pool->nsolvables;   /* place ptr in middle */

  POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "----- propagate level %d -----\n", level);

  /* foreach non-propagated decision */
  while (solv->propagate_index < solv->decisionq.count)
    {
      /*
       * 'pkg' was just decided
       * negate because our watches trigger if literal goes FALSE
       */
      pkg = -solv->decisionq.elements[solv->propagate_index++];
        
      IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
        {
          POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "propagate decision %d:", -pkg);
          solver_printruleelement(solv, SOLV_DEBUG_PROPAGATE, 0, -pkg);
        }

      /* foreach rule where 'pkg' is now FALSE */
      for (rp = watches + pkg; *rp; rp = next_rp)
        {
          r = solv->rules + *rp;
          if (r->d < 0)
            {
              /* rule is disabled, goto next */
              if (pkg == r->w1)
                next_rp = &r->n1;
              else
                next_rp = &r->n2;
              continue;
            }

          IF_POOLDEBUG (SOLV_DEBUG_WATCHES)
            {
              POOL_DEBUG(SOLV_DEBUG_WATCHES, "  watch triggered ");
              solver_printrule(solv, SOLV_DEBUG_WATCHES, r);
            }

          /*
           * 'pkg' was just decided (was set to FALSE), so this rule
           * may now be unit.
           */
          /* find the other watch */
          if (pkg == r->w1)
            {
              other_watch = r->w2;
              next_rp = &r->n1;
            }
          else
            {
              other_watch = r->w1;
              next_rp = &r->n2;
            }

          /*
           * if the other watch is true we have nothing to do
           */
          if (DECISIONMAP_TRUE(other_watch))
            continue;

          /*
           * The other literal is FALSE or UNDEF
           *
           */

          if (r->d)
            {
              /* Not a binary clause, try to move our watch.
               *
               * Go over all literals and find one that is
               *   not other_watch
               *   and not FALSE
               *
               * (TRUE is also ok, in that case the rule is fulfilled)
               * As speed matters here we do not use the FOR_RULELITERALS
               * macro.
               */
              if (r->p                                /* we have a 'p' */
                  && r->p != other_watch              /* which is not watched */
                  && !DECISIONMAP_FALSE(r->p))        /* and not FALSE */
                {
                  p = r->p;
                }
              else                                    /* go find a 'd' to make 'true' */
                {
                  /* foreach p in 'd'
                     we just iterate sequentially, doing it in another order just changes the order of decisions, not the decisions itself
                   */
                  for (dp = pool->whatprovidesdata + r->d; (p = *dp++) != 0;)
                    {
                      if (p != other_watch              /* which is not watched */
                          && !DECISIONMAP_FALSE(p))     /* and not FALSE */
                        break;
                    }
                }

              if (p)
                {
                  /*
                   * if we found some p that is UNDEF or TRUE, move
                   * watch to it
                   */
                  IF_POOLDEBUG (SOLV_DEBUG_WATCHES)
                    {
                      if (p > 0)
                        POOL_DEBUG(SOLV_DEBUG_WATCHES, "    -> move w%d to %s\n", (pkg == r->w1 ? 1 : 2), pool_solvid2str(pool, p));
                      else
                        POOL_DEBUG(SOLV_DEBUG_WATCHES, "    -> move w%d to !%s\n", (pkg == r->w1 ? 1 : 2), pool_solvid2str(pool, -p));
                    }

                  *rp = *next_rp;
                  next_rp = rp;

                  if (pkg == r->w1)
                    {
                      r->w1 = p;
                      r->n1 = watches[p];
                    }
                  else
                    {
                      r->w2 = p;
                      r->n2 = watches[p];
                    }
                  watches[p] = r - solv->rules;
                  continue;
                }
              /* search failed, thus all unwatched literals are FALSE */
                
            } /* not binary */

          /*
           * unit clause found, set literal other_watch to TRUE
           */

          if (DECISIONMAP_FALSE(other_watch))      /* check if literal is FALSE */
            return r;                              /* eek, a conflict! */

          IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
            {
              POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "  unit ");
              solver_printrule(solv, SOLV_DEBUG_PROPAGATE, r);
            }

          if (other_watch > 0)
            decisionmap[other_watch] = level;    /* install! */
          else
            decisionmap[-other_watch] = -level;  /* remove! */

          queue_push(&solv->decisionq, other_watch);
          queue_push(&solv->decisionq_why, r - solv->rules);

          IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
            {
              if (other_watch > 0)
                POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "    -> decided to install %s\n", pool_solvid2str(pool, other_watch));
              else
                POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "    -> decided to conflict %s\n", pool_solvid2str(pool, -other_watch));
            }

        } /* foreach rule involving 'pkg' */
        
    } /* while we have non-decided decisions */

  POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "----- propagate end -----\n");

  return 0;     /* all is well */
}


/********************************************************************/
/* Analysis */

/*-------------------------------------------------------------------
 *
 * revert
 * revert decisionq to a level
 */

static void
revert(Solver *solv, int level)
{
  Pool *pool = solv->pool;
  Id v, vv;
  while (solv->decisionq.count)
    {
      v = solv->decisionq.elements[solv->decisionq.count - 1];
      vv = v > 0 ? v : -v;
      if (solv->decisionmap[vv] <= level && solv->decisionmap[vv] >= -level)
        break;
      POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "reverting decision %d at %d\n", v, solv->decisionmap[vv]);
      solv->decisionmap[vv] = 0;
      solv->decisionq.count--;
      solv->decisionq_why.count--;
      solv->propagate_index = solv->decisionq.count;
    }
  while (solv->branches.count && solv->branches.elements[solv->branches.count - 1] >= level)
    solv->branches.count -= solv->branches.elements[solv->branches.count - 2];
  if (solv->recommends_index > solv->decisionq.count)
    solv->recommends_index = -1;        /* rebuild recommends/suggests maps */
  solv->decisionq_reason.count = level + 1;
}

/*-------------------------------------------------------------------
 *
 * watch2onhighest - put watch2 on literal with highest level
 */

static inline void
watch2onhighest(Solver *solv, Rule *r)
{
  int l, wl = 0;
  Id d, v, *dp;

  d = r->d < 0 ? -r->d - 1 : r->d;
  if (!d)
    return;     /* binary rule, both watches are set */
  dp = solv->pool->whatprovidesdata + d;
  while ((v = *dp++) != 0)
    {
      l = solv->decisionmap[v < 0 ? -v : v];
      if (l < 0)
        l = -l;
      if (l > wl)
        {
          r->w2 = dp[-1];
          wl = l;
        }
    }
}


/*-------------------------------------------------------------------
 *
 * analyze
 *   and learn
 */

static int
analyze(Solver *solv, int level, Rule *c, Rule **lrp)
{
  Pool *pool = solv->pool;
  Queue q;
  Rule *r;
  Id q_buf[8];
  int rlevel = 1;
  Map seen;             /* global? */
  Id p = 0, pp, v, vv, why;
  int l, i, idx;
  int num = 0, l1num = 0;
  int learnt_why = solv->learnt_pool.count;
  Id *decisionmap = solv->decisionmap;

  queue_init_buffer(&q, q_buf, sizeof(q_buf)/sizeof(*q_buf));

  POOL_DEBUG(SOLV_DEBUG_ANALYZE, "ANALYZE at %d ----------------------\n", level);
  map_init(&seen, pool->nsolvables);
  idx = solv->decisionq.count;
  for (;;)
    {
      IF_POOLDEBUG (SOLV_DEBUG_ANALYZE)
        solver_printruleclass(solv, SOLV_DEBUG_ANALYZE, c);
      queue_push(&solv->learnt_pool, c - solv->rules);
      FOR_RULELITERALS(v, pp, c)
        {
          if (DECISIONMAP_TRUE(v))      /* the one true literal */
            continue;
          vv = v > 0 ? v : -v;
          if (MAPTST(&seen, vv))
            continue;
          MAPSET(&seen, vv);            /* mark that we also need to look at this literal */
          l = solv->decisionmap[vv];
          if (l < 0)
            l = -l;
          if (l == 1)
            l1num++;                    /* need to do this one in level1 pass */
          else if (l == level)
            num++;                      /* need to do this one as well */
          else
            {
              queue_push(&q, v);        /* not level1 or conflict level, add to new rule */
              if (l > rlevel)
                rlevel = l;
            }
        }
l1retry:
      if (!num && !--l1num)
        break;  /* all literals done */

      /* find the next literal to investigate */
      /* (as num + l1num > 0, we know that we'll always find one) */
      for (;;)
        {
          assert(idx > 0);
          v = solv->decisionq.elements[--idx];
          vv = v > 0 ? v : -v;
          if (MAPTST(&seen, vv))
            break;
        }
      MAPCLR(&seen, vv);

      if (num && --num == 0)
        {
          /* done with normal literals, now start level 1 literal processing */
          p = -v;       /* so that v doesn't get lost */
          if (!l1num)
            break;
          POOL_DEBUG(SOLV_DEBUG_ANALYZE, "got %d involved level 1 decisions\n", l1num);
          /* clear non-l1 bits from seen map */
          for (i = 0; i < q.count; i++)
            {
              v = q.elements[i];
              MAPCLR(&seen, v > 0 ? v : -v);
            }
          /* only level 1 marks left in seen map */
          l1num++;      /* as l1retry decrements it */
          goto l1retry;
        }

      why = solv->decisionq_why.elements[idx];
      if (why <= 0)     /* just in case, maybe for SYSTEMSOLVABLE */
        goto l1retry;
      c = solv->rules + why;
    }
  map_free(&seen);
  assert(p != 0);
  assert(rlevel > 0 && rlevel < level);
  IF_POOLDEBUG (SOLV_DEBUG_ANALYZE)
    {
      POOL_DEBUG(SOLV_DEBUG_ANALYZE, "learned rule for level %d (am %d)\n", rlevel, level);
      solver_printruleelement(solv, SOLV_DEBUG_ANALYZE, 0, p);
      for (i = 0; i < q.count; i++)
        solver_printruleelement(solv, SOLV_DEBUG_ANALYZE, 0, q.elements[i]);
    }
  /* push end marker on learnt reasons stack */
  queue_push(&solv->learnt_pool, 0);
  solv->stats_learned++;

  POOL_DEBUG(SOLV_DEBUG_ANALYZE, "reverting decisions (level %d -> %d)\n", level, rlevel);
  level = rlevel;
  revert(solv, level);
  if (q.count < 2)
    {
      Id d = q.count ? q.elements[0] : 0;
      queue_free(&q);
      r = solver_addrule(solv, p, d, 0);
    }
  else
    {
      Id d = pool_queuetowhatprovides(pool, &q);
      queue_free(&q);
      r = solver_addrule(solv, p, 0, d);
    }
  assert(solv->learnt_why.count == (r - solv->rules) - solv->learntrules);
  queue_push(&solv->learnt_why, learnt_why);
  if (r->w2)
    {
      /* needs watches */
      watch2onhighest(solv, r);
      addwatches_rule(solv, r);
    }
  else
    {
      /* rule is an assertion */
      queue_push(&solv->ruleassertions, r - solv->rules);
    }
  *lrp = r;
  return level;
}


/*-------------------------------------------------------------------
 *
 * solver_reset
 *
 * reset all solver decisions
 * called after rules have been enabled/disabled
 */

void
solver_reset(Solver *solv)
{
  int i;
  Id v;

  /* rewind all decisions */
  for (i = solv->decisionq.count - 1; i >= 0; i--)
    {
      v = solv->decisionq.elements[i];
      solv->decisionmap[v > 0 ? v : -v] = 0;
    }
  queue_empty(&solv->decisionq_why);
  queue_empty(&solv->decisionq);
  queue_empty(&solv->decisionq_reason);
  solv->recommends_index = -1;
  solv->propagate_index = 0;
  queue_empty(&solv->branches);

  /* adapt learnt rule status to new set of enabled/disabled rules */
  enabledisablelearntrules(solv);
}

static inline int
queue_contains(Queue *q, Id id)
{
  int i;
  for (i = 0; i < q->count; i++)
    if (q->elements[i] == id)
      return 1;
  return 0;
}

static void
disable_recommendsrules(Solver *solv, Queue *weakq)
{
  Pool *pool = solv->pool;
  int i, rid;
  for (i = 0; i < weakq->count; i++)
    {
      rid = weakq->elements[i];
      if ((rid >= solv->recommendsrules && rid < solv->recommendsrules_end) || queue_contains(solv->recommendsruleq, rid))
        {
          Rule *r = solv->rules + rid;
          if (r->d >= 0)
            {
              POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "disabling ");
              solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, r);
              solver_disablerule(solv, r);
            }
        }
    }
}

/*-------------------------------------------------------------------
 *
 * analyze_unsolvable_rule
 *
 * recursion helper used by analyze_unsolvable
 */

static void
analyze_unsolvable_rule(Solver *solv, Rule *r, Queue *weakq, Map *rseen)
{
  Pool *pool = solv->pool;
  int i;
  Id why = r - solv->rules;

  IF_POOLDEBUG (SOLV_DEBUG_UNSOLVABLE)
    solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, r);
  if (solv->learntrules && why >= solv->learntrules)
    {
      if (MAPTST(rseen, why - solv->learntrules))
        return;
      MAPSET(rseen, why - solv->learntrules);
      for (i = solv->learnt_why.elements[why - solv->learntrules]; solv->learnt_pool.elements[i]; i++)
        if (solv->learnt_pool.elements[i] > 0)
          analyze_unsolvable_rule(solv, solv->rules + solv->learnt_pool.elements[i], weakq, rseen);
      return;
    }
  if (solv->weakrulemap.size && MAPTST(&solv->weakrulemap, why) && weakq)
    queue_push(weakq, why);
  /* add non-pkg rules to problem and disable */
  if (why >= solv->pkgrules_end)
    solver_recordproblem(solv, why);
}

/* fix a problem by disabling one or more weak rules */
static void
disable_weakrules(Solver *solv, Queue *weakq)
{
  Pool *pool = solv->pool;
  int i;
  Id lastweak = 0;
  for (i = 0; i < weakq->count; i++)
    if (weakq->elements[i] > lastweak)
      lastweak = weakq->elements[i];
  if (lastweak >= solv->recommendsrules && lastweak < solv->recommendsrules_end)
    {
      lastweak = 0;
      for (i = 0; i < weakq->count; i++)
        if (weakq->elements[i] < solv->recommendsrules && weakq->elements[i] > lastweak)
          lastweak = weakq->elements[i];
      if (lastweak < solv->pkgrules_end)
        {
          disable_recommendsrules(solv, weakq);
          return;
        }
    }
  if (lastweak < solv->pkgrules_end && solv->strongrecommends && solv->recommendsruleq && queue_contains(solv->recommendsruleq, lastweak))
    {
      disable_recommendsrules(solv, weakq);
      return;
    }
  POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "disabling ");
  solver_printruleclass(solv, SOLV_DEBUG_UNSOLVABLE, solv->rules + lastweak);
  /* choice rules need special handling */
  if (lastweak >= solv->choicerules && lastweak < solv->choicerules_end)
    solver_disablechoicerules(solv, solv->rules + lastweak);
  else
    solver_fixproblem(solv, lastweak);
}

/*-------------------------------------------------------------------
 *
 * analyze_unsolvable (called from setpropagatelearn)
 *
 * We know that the problem is not solvable. Record all involved
 * rules (i.e. the "proof") into solv->learnt_pool.
 * Record the learnt pool index and all non-pkg rules into
 * solv->problems. (Our solutions to fix the problems are to
 * disable those rules.)
 *
 * If the proof contains at least one weak rule, we disable the
 * last of them.
 *
 * Otherwise we return -1 if disablerules is not set or disable
 * _all_ of the problem rules and return 0.
 *
 * return:  0 - disabled some rules, try again
 *         -1 - hopeless
 */

static int
analyze_unsolvable(Solver *solv, Rule *cr, int disablerules)
{
  Pool *pool = solv->pool;
  Rule *r;
  Map involved;         /* global to speed things up? */
  Map rseen;
  Queue weakq;
  Id pp, v, vv, why;
  int idx;
  Id *decisionmap = solv->decisionmap;
  int oldproblemcount;
  int oldlearntpoolcount;
  int record_proof = 1;

  POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "ANALYZE UNSOLVABLE ----------------------\n");
  solv->stats_unsolvable++;
  oldproblemcount = solv->problems.count;
  oldlearntpoolcount = solv->learnt_pool.count;

  /* make room for proof index */
  /* must update it later, as analyze_unsolvable_rule would confuse
   * it with a rule index if we put the real value in already */
  queue_push(&solv->problems, 0);

  r = cr;
  map_init(&involved, pool->nsolvables);
  map_init(&rseen, solv->learntrules ? solv->nrules - solv->learntrules : 0);
  queue_init(&weakq);
  if (record_proof)
    queue_push(&solv->learnt_pool, r - solv->rules);
  analyze_unsolvable_rule(solv, r, &weakq, &rseen);
  FOR_RULELITERALS(v, pp, r)
    {
      if (DECISIONMAP_TRUE(v))  /* the one true literal */
          continue;
      vv = v > 0 ? v : -v;
      MAPSET(&involved, vv);
    }
  idx = solv->decisionq.count;
  while (idx > 0)
    {
      v = solv->decisionq.elements[--idx];
      vv = v > 0 ? v : -v;
      if (!MAPTST(&involved, vv) || vv == SYSTEMSOLVABLE)
        continue;
      why = solv->decisionq_why.elements[idx];
      assert(why > 0);
      if (record_proof)
        queue_push(&solv->learnt_pool, why);
      r = solv->rules + why;
      analyze_unsolvable_rule(solv, r, &weakq, &rseen);
      FOR_RULELITERALS(v, pp, r)
        {
          if (DECISIONMAP_TRUE(v))      /* the one true literal */
              continue;
          vv = v > 0 ? v : -v;
          MAPSET(&involved, vv);
        }
    }
  map_free(&involved);
  map_free(&rseen);
  queue_push(&solv->problems, 0);       /* mark end of this problem */

  if (weakq.count)
    {
      /* revert problems */
      solv->problems.count = oldproblemcount;
      solv->learnt_pool.count = oldlearntpoolcount;
      /* disable some weak rules */
      disable_weakrules(solv, &weakq);
      queue_free(&weakq);
      solver_reset(solv);
      return 0;
    }
  queue_free(&weakq);

  if (solv->allowuninstall || solv->allowuninstall_all || solv->allowuninstallmap.size)
    if (solver_autouninstall(solv, oldproblemcount) != 0)
      {
        solv->problems.count = oldproblemcount;
        solv->learnt_pool.count = oldlearntpoolcount;
        solver_reset(solv);
        return 0;
      }

  /* finish proof */
  if (record_proof)
    {
      queue_push(&solv->learnt_pool, 0);
      solv->problems.elements[oldproblemcount] = oldlearntpoolcount;
    }

  /* + 2: index + trailing zero */
  if (disablerules && oldproblemcount + 2 < solv->problems.count)
    {
      solver_disableproblemset(solv, oldproblemcount);
      /* XXX: might want to enable all weak rules again */
      solver_reset(solv);
      return 0;
    }
  POOL_DEBUG(SOLV_DEBUG_UNSOLVABLE, "UNSOLVABLE\n");
  return -1;
}


/*-------------------------------------------------------------------
 *
 * setpropagatelearn
 *
 * add free decision (solvable to install) to decisionq
 * increase level and propagate decision
 * return if no conflict.
 *
 * in conflict case, analyze conflict rule, add resulting
 * rule to learnt rule set, make decision from learnt
 * rule (always unit) and re-propagate.
 *
 * returns the new solver level or -1 if unsolvable
 *
 */

static int
setpropagatelearn(Solver *solv, int level, Id decision, int disablerules, Id ruleid, Id reason)
{
  Pool *pool = solv->pool;
  Rule *r, *lr;

  if (decision)
    {
      level++;
      if (decision > 0)
        solv->decisionmap[decision] = level;
      else
        solv->decisionmap[-decision] = -level;
      queue_push(&solv->decisionq, decision);
      queue_push(&solv->decisionq_why, -ruleid);        /* <= 0 -> free decision */
      queue_push(&solv->decisionq_reason, reason);
    }
  assert(ruleid >= 0 && level > 0);
  for (;;)
    {
      r = propagate(solv, level);
      if (!r)
        break;
      if (level == 1)
        return analyze_unsolvable(solv, r, disablerules);
      POOL_DEBUG(SOLV_DEBUG_ANALYZE, "conflict with rule #%d\n", (int)(r - solv->rules));
      level = analyze(solv, level, r, &lr);
      /* the new rule is unit by design */
      decision = lr->p;
      solv->decisionmap[decision > 0 ? decision : -decision] = decision > 0 ? level : -level;
      queue_push(&solv->decisionq, decision);
      queue_push(&solv->decisionq_why, lr - solv->rules);
      IF_POOLDEBUG (SOLV_DEBUG_ANALYZE)
        {
          POOL_DEBUG(SOLV_DEBUG_ANALYZE, "decision: ");
          solver_printruleelement(solv, SOLV_DEBUG_ANALYZE, 0, decision);
          POOL_DEBUG(SOLV_DEBUG_ANALYZE, "new rule: ");
          solver_printrule(solv, SOLV_DEBUG_ANALYZE, lr);
        }
    }
  return level;
}

static void
reorder_dq_for_future_installed(Solver *solv, int level, Queue *dq)
{
  Pool *pool = solv->pool;
  int i, j, haveone = 0, dqcount = dq->count;
  int decisionqcount = solv->decisionq.count;
  Id p;
  Solvable *s;

  /* at the time we process jobrules the installed packages are not kept yet */
  /* reorder so that "future-supplemented" packages come first */
  FOR_REPO_SOLVABLES(solv->installed, p, s)
    {
      if (MAPTST(&solv->noupdate, p - solv->installed->start))
        continue;
      if (solv->decisionmap[p] == 0)
        {
          if (s->recommends || s->suggests)
            queue_push(&solv->decisionq, p);
          solv->decisionmap[p] = level + 1;
          haveone = 1;
        }
    }
  if (!haveone)
    return;
  policy_update_recommendsmap(solv);
  for (i = 0; i < dqcount; i++)
    {
      p = dq->elements[i];
      if (!(pool->solvables[p].repo == solv->installed || MAPTST(&solv->suggestsmap, p) || solver_is_enhancing(solv, pool->solvables + p)))
        {
          queue_push(dq, p);
          dq->elements[i] = 0;
        }
    }
  dqcount = dq->count;
  for (i = 0; i < dqcount; i++)
    {
      p = dq->elements[i];
      if (p && !(pool->solvables[p].repo == solv->installed || MAPTST(&solv->recommendsmap, p) || solver_is_supplementing(solv, pool->solvables + p)))
        {
          queue_push(dq, p);
          dq->elements[i] = 0;
        }
    }
  for (i = j = 0; i < dq->count; i++)
    if (dq->elements[i])
      dq->elements[j++] = dq->elements[i];
  queue_truncate(dq, j);
  FOR_REPO_SOLVABLES(solv->installed, p, s)
    if (solv->decisionmap[p] == level + 1)
      solv->decisionmap[p] = 0;
  if (solv->decisionq.count != decisionqcount)
    {
      solv->recommends_index = -1;
      queue_truncate(&solv->decisionq, decisionqcount);
    }
  /* but obey favored maps */
  policy_prefer_favored(solv, dq);
}

/*-------------------------------------------------------------------
 *
 * branch handling
 *
 * format is:
 *   [ -p1 p2 p3 .. pn  opt_pkg opt_data size level ]
 *
 * pkgs are negative if we tried them (to prevent inifinite recursion)
 * opt_pkg:  recommends: package with the recommends
 *           rule: 0
 * opt_data: recommends: depid
 *           rule: ruleid
 */

static void
createbranch(Solver *solv, int level, Queue *dq, Id p, Id data)
{
  Pool *pool = solv->pool;
  int i;
  IF_POOLDEBUG (SOLV_DEBUG_POLICY)
    {
      POOL_DEBUG (SOLV_DEBUG_POLICY, "creating a branch:\n");
      for (i = 0; i < dq->count; i++)
        POOL_DEBUG (SOLV_DEBUG_POLICY, "  - %s\n", pool_solvid2str(pool, dq->elements[i]));
    }
  queue_push(&solv->branches, -dq->elements[0]);
  for (i = 1; i < dq->count; i++)
    queue_push(&solv->branches, dq->elements[i]);
  queue_push2(&solv->branches, p, data);
  queue_push2(&solv->branches, dq->count + 4, level);
}

static int
takebranch(Solver *solv, int pos, int end, const char *msg, int disablerules)
{
  Pool *pool = solv->pool;
  int level;
  Id p, why, reason;
#if 0
  {
    int i;
    printf("branch group level %d [%d-%d] %d %d:\n", solv->branches.elements[end - 1], start, end, solv->branches.elements[end - 4], solv->branches.elements[end - 3]);
    for (i = end - solv->branches.elements[end - 2]; i < end - 4; i++)
      printf("%c %c%s\n", i == pos ? 'x' : ' ', solv->branches.elements[i] >= 0 ? ' ' : '-', pool_solvid2str(pool, solv->branches.elements[i] >= 0 ? solv->branches.elements[i] : -solv->branches.elements[i]));
  }
#endif
  level = solv->branches.elements[end - 1];
  p = solv->branches.elements[pos];
  solv->branches.elements[pos] = -p;
  POOL_DEBUG(SOLV_DEBUG_SOLVER, "%s %d -> %d with %s\n", msg, solv->decisionmap[p], level, pool_solvid2str(pool, p));
  /* hack: set level to zero so that revert does not remove the branch */
  solv->branches.elements[end - 1] = 0;
  revert(solv, level);
  solv->branches.elements[end - 1] = level;
  /* hack: revert simply sets the count, so we can still access the reverted elements */
  why = -solv->decisionq_why.elements[solv->decisionq_why.count];
  assert(why >= 0);
  reason = solv->decisionq_reason.elements[level + 1];
  return setpropagatelearn(solv, level, p, disablerules, why, reason);
}

/*-------------------------------------------------------------------
 *
 * select and install
 *
 * install best package from the queue. We add an extra package, inst, if
 * provided. See comment in weak install section.
 *
 * returns the new solver level or -1 if unsolvable
 *
 */

static int
selectandinstall(Solver *solv, int level, Queue *dq, int disablerules, Id ruleid, Id reason)
{
  Pool *pool = solv->pool;
  Id p;

  if (dq->count > 1)
    policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
  /* if we're resolving rules and didn't resolve the installed packages yet,
   * do some special supplements ordering */
  if (dq->count > 1 && solv->do_extra_reordering)
    reorder_dq_for_future_installed(solv, level, dq);
  /* if we have multiple candidates we open a branch */
  if (dq->count > 1)
    createbranch(solv, level, dq, 0, ruleid);
  p = dq->elements[0];
  POOL_DEBUG(SOLV_DEBUG_POLICY, "installing %s\n", pool_solvid2str(pool, p));
  return setpropagatelearn(solv, level, p, disablerules, ruleid, reason);
}


/********************************************************************/
/* Main solver interface */


/*-------------------------------------------------------------------
 *
 * solver_create
 * create solver structure
 *
 * pool: all available solvables
 * installed: installed Solvables
 *
 *
 * Upon solving, rules are created to flag the Solvables
 * of the 'installed' Repo as installed.
 */

Solver *
solver_create(Pool *pool)
{
  Solver *solv;
  solv = (Solver *)solv_calloc(1, sizeof(Solver));
  solv->pool = pool;
  solv->installed = pool->installed;

  solv->allownamechange = 1;

  solv->dup_allowdowngrade = 1;
  solv->dup_allownamechange = 1;
  solv->dup_allowarchchange = 1;
  solv->dup_allowvendorchange = 1;

  solv->keepexplicitobsoletes = pool->noobsoletesmultiversion ? 0 : 1;

  queue_init(&solv->ruletojob);
  queue_init(&solv->decisionq);
  queue_init(&solv->decisionq_why);
  queue_init(&solv->decisionq_reason);
  queue_init(&solv->problems);
  queue_init(&solv->orphaned);
  queue_init(&solv->learnt_why);
  queue_init(&solv->learnt_pool);
  queue_init(&solv->branches);
  queue_init(&solv->weakruleq);
  queue_init(&solv->ruleassertions);
  queue_init(&solv->addedmap_deduceq);

  queue_push(&solv->learnt_pool, 0);    /* so that 0 does not describe a proof */

  map_init(&solv->recommendsmap, pool->nsolvables);
  map_init(&solv->suggestsmap, pool->nsolvables);
  map_init(&solv->noupdate, solv->installed ? solv->installed->end - solv->installed->start : 0);
  solv->recommends_index = 0;

  solv->decisionmap = (Id *)solv_calloc(pool->nsolvables, sizeof(Id));
  solv->nrules = 1;
  solv->rules = solv_extend_resize(solv->rules, solv->nrules, sizeof(Rule), RULES_BLOCK);
  memset(solv->rules, 0, sizeof(Rule));

  return solv;
}



/*-------------------------------------------------------------------
 *
 * solver_free
 */

static inline void
queuep_free(Queue **qp)
{
  if (!*qp)
    return;
  queue_free(*qp);
  *qp = solv_free(*qp);
}

static inline void
map_zerosize(Map *m)
{
  if (m->size)
    {
      map_free(m);
      map_init(m, 0);
    }
}

void
solver_free(Solver *solv)
{
  queue_free(&solv->job);
  queue_free(&solv->ruletojob);
  queue_free(&solv->decisionq);
  queue_free(&solv->decisionq_why);
  queue_free(&solv->decisionq_reason);
  queue_free(&solv->learnt_why);
  queue_free(&solv->learnt_pool);
  queue_free(&solv->problems);
  queue_free(&solv->solutions);
  queue_free(&solv->orphaned);
  queue_free(&solv->branches);
  queue_free(&solv->weakruleq);
  queue_free(&solv->ruleassertions);
  queue_free(&solv->addedmap_deduceq);
  queuep_free(&solv->cleandeps_updatepkgs);
  queuep_free(&solv->cleandeps_mistakes);
  queuep_free(&solv->update_targets);
  queuep_free(&solv->installsuppdepq);
  queuep_free(&solv->recommendscplxq);
  queuep_free(&solv->suggestscplxq);
  queuep_free(&solv->brokenorphanrules);
  queuep_free(&solv->recommendsruleq);

  map_free(&solv->recommendsmap);
  map_free(&solv->suggestsmap);
  map_free(&solv->noupdate);
  map_free(&solv->weakrulemap);
  map_free(&solv->multiversion);

  map_free(&solv->updatemap);
  map_free(&solv->bestupdatemap);
  map_free(&solv->fixmap);
  map_free(&solv->dupmap);
  map_free(&solv->dupinvolvedmap);
  map_free(&solv->droporphanedmap);
  map_free(&solv->cleandepsmap);
  map_free(&solv->allowuninstallmap);

  solv_free(solv->favormap);
  solv_free(solv->decisionmap);
  solv_free(solv->rules);
  solv_free(solv->watches);
  solv_free(solv->obsoletes);
  solv_free(solv->obsoletes_data);
  solv_free(solv->specialupdaters);
  solv_free(solv->choicerules_info);
  solv_free(solv->bestrules_info);
  solv_free(solv->yumobsrules_info);
  solv_free(solv->recommendsrules_info);
  solv_free(solv->instbuddy);
  solv_free(solv);
}

int
solver_get_flag(Solver *solv, int flag)
{
  switch (flag)
  {
  case SOLVER_FLAG_ALLOW_DOWNGRADE:
    return solv->allowdowngrade;
  case SOLVER_FLAG_ALLOW_NAMECHANGE:
    return solv->allownamechange;
  case SOLVER_FLAG_ALLOW_ARCHCHANGE:
    return solv->allowarchchange;
  case SOLVER_FLAG_ALLOW_VENDORCHANGE:
    return solv->allowvendorchange;
  case SOLVER_FLAG_ALLOW_UNINSTALL:
    return solv->allowuninstall;
  case SOLVER_FLAG_NO_UPDATEPROVIDE:
    return solv->noupdateprovide;
  case SOLVER_FLAG_SPLITPROVIDES:
    return solv->dosplitprovides;
  case SOLVER_FLAG_IGNORE_RECOMMENDED:
    return solv->dontinstallrecommended;
  case SOLVER_FLAG_ADD_ALREADY_RECOMMENDED:
    return solv->addalreadyrecommended;
  case SOLVER_FLAG_NO_INFARCHCHECK:
    return solv->noinfarchcheck;
  case SOLVER_FLAG_KEEP_EXPLICIT_OBSOLETES:
    return solv->keepexplicitobsoletes;
  case SOLVER_FLAG_BEST_OBEY_POLICY:
    return solv->bestobeypolicy;
  case SOLVER_FLAG_NO_AUTOTARGET:
    return solv->noautotarget;
  case SOLVER_FLAG_DUP_ALLOW_DOWNGRADE:
    return solv->dup_allowdowngrade;
  case SOLVER_FLAG_DUP_ALLOW_NAMECHANGE:
    return solv->dup_allownamechange;
  case SOLVER_FLAG_DUP_ALLOW_ARCHCHANGE:
    return solv->dup_allowarchchange;
  case SOLVER_FLAG_DUP_ALLOW_VENDORCHANGE:
    return solv->dup_allowvendorchange;
  case SOLVER_FLAG_KEEP_ORPHANS:
    return solv->keep_orphans;
  case SOLVER_FLAG_BREAK_ORPHANS:
    return solv->break_orphans;
  case SOLVER_FLAG_FOCUS_INSTALLED:
    return solv->focus_installed;
  case SOLVER_FLAG_FOCUS_BEST:
    return solv->focus_best;
  case SOLVER_FLAG_YUM_OBSOLETES:
    return solv->do_yum_obsoletes;
  case SOLVER_FLAG_NEED_UPDATEPROVIDE:
    return solv->needupdateprovide;
  case SOLVER_FLAG_URPM_REORDER:
    return solv->urpmreorder;
  case SOLVER_FLAG_STRONG_RECOMMENDS:
    return solv->strongrecommends;
  case SOLVER_FLAG_INSTALL_ALSO_UPDATES:
    return solv->install_also_updates;
  case SOLVER_FLAG_ONLY_NAMESPACE_RECOMMENDED:
    return solv->only_namespace_recommended;
  default:
    break;
  }
  return -1;
}

int
solver_set_flag(Solver *solv, int flag, int value)
{
  int old = solver_get_flag(solv, flag);
  switch (flag)
  {
  case SOLVER_FLAG_ALLOW_DOWNGRADE:
    solv->allowdowngrade = value;
    break;
  case SOLVER_FLAG_ALLOW_NAMECHANGE:
    solv->allownamechange = value;
    break;
  case SOLVER_FLAG_ALLOW_ARCHCHANGE:
    solv->allowarchchange = value;
    break;
  case SOLVER_FLAG_ALLOW_VENDORCHANGE:
    solv->allowvendorchange = value;
    break;
  case SOLVER_FLAG_ALLOW_UNINSTALL:
    solv->allowuninstall = value;
    break;
  case SOLVER_FLAG_NO_UPDATEPROVIDE:
    solv->noupdateprovide = value;
    break;
  case SOLVER_FLAG_SPLITPROVIDES:
    solv->dosplitprovides = value;
    break;
  case SOLVER_FLAG_IGNORE_RECOMMENDED:
    solv->dontinstallrecommended = value;
    break;
  case SOLVER_FLAG_ADD_ALREADY_RECOMMENDED:
    solv->addalreadyrecommended = value;
    break;
  case SOLVER_FLAG_NO_INFARCHCHECK:
    solv->noinfarchcheck = value;
    break;
  case SOLVER_FLAG_KEEP_EXPLICIT_OBSOLETES:
    solv->keepexplicitobsoletes = value;
    break;
  case SOLVER_FLAG_BEST_OBEY_POLICY:
    solv->bestobeypolicy = value;
    break;
  case SOLVER_FLAG_NO_AUTOTARGET:
    solv->noautotarget = value;
    break;
  case SOLVER_FLAG_DUP_ALLOW_DOWNGRADE:
    solv->dup_allowdowngrade = value;
    break;
  case SOLVER_FLAG_DUP_ALLOW_NAMECHANGE:
    solv->dup_allownamechange = value;
    break;
  case SOLVER_FLAG_DUP_ALLOW_ARCHCHANGE:
    solv->dup_allowarchchange = value;
    break;
  case SOLVER_FLAG_DUP_ALLOW_VENDORCHANGE:
    solv->dup_allowvendorchange = value;
    break;
  case SOLVER_FLAG_KEEP_ORPHANS:
    solv->keep_orphans = value;
    break;
  case SOLVER_FLAG_BREAK_ORPHANS:
    solv->break_orphans = value;
    break;
  case SOLVER_FLAG_FOCUS_INSTALLED:
    solv->focus_installed = value;
    break;
  case SOLVER_FLAG_FOCUS_BEST:
    solv->focus_best = value;
    break;
  case SOLVER_FLAG_YUM_OBSOLETES:
    solv->do_yum_obsoletes = value;
    break;
  case SOLVER_FLAG_NEED_UPDATEPROVIDE:
    solv->needupdateprovide = value;
    break;
  case SOLVER_FLAG_URPM_REORDER:
    solv->urpmreorder = value;
    break;
  case SOLVER_FLAG_STRONG_RECOMMENDS:
    solv->strongrecommends = value;
    break;
  case SOLVER_FLAG_INSTALL_ALSO_UPDATES:
    solv->install_also_updates = value;
    break;
  case SOLVER_FLAG_ONLY_NAMESPACE_RECOMMENDED:
    solv->only_namespace_recommended = value;
    break;
  default:
    break;
  }
  return old;
}

static int
resolve_jobrules(Solver *solv, int level, int disablerules, Queue *dq)
{
  Pool *pool = solv->pool;
  int oldlevel = level;
  int i, olevel;
  Rule *r;

  POOL_DEBUG(SOLV_DEBUG_SOLVER, "resolving job rules\n");
  for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
    {
      Id l, pp;
      if (r->d < 0)             /* ignore disabled rules */
        continue;
      queue_empty(dq);
      FOR_RULELITERALS(l, pp, r)
        {
          if (l < 0)
            {
              if (solv->decisionmap[-l] <= 0)
                break;
            }
          else
            {
              if (solv->decisionmap[l] > 0)
                break;
              if (solv->decisionmap[l] == 0)
                queue_push(dq, l);
            }
        }
      if (l || !dq->count)
        continue;
      /* prune to installed if not updating */
      if (dq->count > 1 && solv->installed && !solv->updatemap_all &&
          !solv->install_also_updates &&
          !(solv->job.elements[solv->ruletojob.elements[i - solv->jobrules]] & SOLVER_ORUPDATE))
        {
          int j = dq->count, k;
          if (solv->updatemap.size)
            {
              /* do not prune if an installed package wants to be updated */
              for (j = 0; j < dq->count; j++)
                if (pool->solvables[dq->elements[j]].repo == solv->installed
                    && MAPTST(&solv->updatemap, dq->elements[j] - solv->installed->start))
                  break;
            }
          if (j == dq->count)
            {
              for (j = k = 0; j < dq->count; j++)
                if (pool->solvables[dq->elements[j]].repo == solv->installed)
                  dq->elements[k++] = dq->elements[j];
              if (k)
                dq->count = k;
            }
        }
      olevel = level;
      level = selectandinstall(solv, level, dq, disablerules, i, SOLVER_REASON_RESOLVE_JOB);
      if (level <= olevel)
        {
          if (level == olevel)
            {
              i--;
              r--;
              continue; /* try something else */
            }
          if (level < oldlevel)
            return level;
          /* redo from start of jobrules */
          i = solv->jobrules - 1;
          r = solv->rules + i;
        }
    }
  return level;
}

static void
prune_to_update_targets(Solver *solv, Id *cp, Queue *q)
{
  int i, j;
  Id p, *cp2;
  for (i = j = 0; i < q->count; i++)
    {
      p = q->elements[i];
      for (cp2 = cp; *cp2; cp2++)
        if (*cp2 == p)
          {
            q->elements[j++] = p;
            break;
          }
    }
  queue_truncate(q, j);
}

static int
resolve_installed(Solver *solv, int level, int disablerules, Queue *dq)
{
  Pool *pool = solv->pool;
  Repo *installed = solv->installed;
  int i, n, pass;
  int installedpos = solv->installedpos;
  Solvable *s;
  Id p, pp;
  int olevel, origlevel = level;

  POOL_DEBUG(SOLV_DEBUG_SOLVER, "resolving installed packages\n");
  if (!installedpos)
    installedpos = installed->start;
  /* we use two passes if we need to update packages
   * to create a better user experience */
  for (pass = solv->updatemap.size ? 0 : 1; pass < 2; )
    {
      int passlevel = level;
      Id *specialupdaters = solv->specialupdaters;
      /* start with installedpos, the position that gave us problems the last time */
      for (i = installedpos, n = installed->start; n < installed->end; i++, n++)
        {
          Rule *r, *rr;
          Id d;

          if (i == installed->end)
            i = installed->start;
          s = pool->solvables + i;
          if (s->repo != installed)
            continue;

          if (solv->decisionmap[i] > 0 && (!specialupdaters || !specialupdaters[i - installed->start]))
            continue;           /* already decided */
          if (!pass && solv->updatemap.size && !MAPTST(&solv->updatemap, i - installed->start))
            continue;           /* updates first */
          r = solv->rules + solv->updaterules + (i - installed->start);
          rr = r;
          if (!rr->p || rr->d < 0)      /* disabled -> look at feature rule */
            rr -= solv->installed->end - solv->installed->start;
          if (!rr->p)           /* identical to update rule? */
            rr = r;
          if (!rr->p)
            continue;           /* orpaned package or pseudo package */

          /* check if we should update this package to the latest version
           * noupdate is set for erase jobs, in that case we want to deinstall
           * the installed package and not replace it with a newer version
           * rr->p != i is for dup jobs where the installed package cannot be kept */
          if (dq->count)
            queue_empty(dq);
          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 && rr->p != i)))
            {
              if (specialupdaters && (d = specialupdaters[i - installed->start]) != 0)
                {
                  /* special multiversion handling, make sure best version is chosen */
                  if (rr->p == i && solv->decisionmap[i] >= 0)
                    queue_push(dq, i);
                  while ((p = pool->whatprovidesdata[d++]) != 0)
                    if (solv->decisionmap[p] >= 0)
                      queue_push(dq, p);
                  if (dq->count && solv->update_targets && solv->update_targets->elements[i - installed->start])
                    prune_to_update_targets(solv, solv->update_targets->elements + solv->update_targets->elements[i - installed->start], dq);
                  if (dq->count)
                    {
                      policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
                      p = dq->elements[0];
                      if (p != i && solv->decisionmap[p] == 0)
                        {
                          rr = solv->rules + solv->featurerules + (i - solv->installed->start);
                          if (!rr->p)           /* update rule == feature rule? */
                            rr = rr - solv->featurerules + solv->updaterules;
                          dq->count = 1;
                        }
                      else
                        dq->count = 0;
                    }
                }
              else
                {
                  /* update to best package of the update rule */
                  FOR_RULELITERALS(p, pp, rr)
                    {
                      if (solv->decisionmap[p] > 0)
                        {
                          dq->count = 0;                /* already fulfilled */
                          break;
                        }
                      if (!solv->decisionmap[p])
                        queue_push(dq, p);
                    }
                }
            }
          if (dq->count && solv->update_targets && solv->update_targets->elements[i - installed->start])
            prune_to_update_targets(solv, solv->update_targets->elements + solv->update_targets->elements[i - installed->start], dq);
          /* install best version */
          if (dq->count)
            {
              olevel = level;
              level = selectandinstall(solv, level, dq, disablerules, rr - solv->rules, SOLVER_REASON_UPDATE_INSTALLED);
              if (level <= olevel)
                {
                  if (level < passlevel)
                    break;      /* trouble */
                  if (level < olevel)
                    n = installed->start;       /* redo all */
                  i--;
                  n--;
                  continue;
                }
            }
          /* if still undecided keep package */
          if (solv->decisionmap[i] == 0)
            {
              olevel = level;
              if (solv->cleandepsmap.size && MAPTST(&solv->cleandepsmap, i - installed->start))
                {
#if 0
                  POOL_DEBUG(SOLV_DEBUG_POLICY, "cleandeps erasing %s\n", pool_solvid2str(pool, i));
                  level = setpropagatelearn(solv, level, -i, disablerules, 0, SOLVER_REASON_CLEANDEPS_ERASE);
#else
                  continue;
#endif
                }
              else
                {
                  POOL_DEBUG(SOLV_DEBUG_POLICY, "keeping %s\n", pool_solvid2str(pool, i));
                  level = setpropagatelearn(solv, level, i, disablerules, r - solv->rules, SOLVER_REASON_KEEP_INSTALLED);
                }
              if (level <= olevel)
                {
                  if (level < passlevel)
                    break;      /* trouble */
                  if (level < olevel)
                    n = installed->start;       /* redo all */
                  i--;
                  n--;
                  continue;     /* retry with learnt rule */
                }
            }
        }
      if (n < installed->end)
        {
          installedpos = i;     /* retry problem solvable next time */
          if (level < origlevel)
            break;              /* ran into trouble */
          /* re-run all passes */
          pass = solv->updatemap.size ? 0 : 1;
          continue;
        }
      /* reset installedpos, advance to next pass */
      installedpos = installed->start;
      pass++;
    }
  solv->installedpos = installedpos;
  return level;
}

/* one or more installed cleandeps packages in dq that are to be updated */
/* we need to emulate the code in resolve_installed */
static void
do_cleandeps_update_filter(Solver *solv, Queue *dq)
{
  Pool *pool = solv->pool;
  Repo *installed = solv->installed;
  Id *specialupdaters = solv->specialupdaters;
  Id p, p2, pp, d;
  Queue q;
  int i, j, k;

  queue_init(&q);
  for (i = 0; i < dq->count; i++)
    {
      Id p = dq->elements[i];
      if (p < 0)
        p = -p;
      if (pool->solvables[p].repo != installed || !MAPTST(&solv->cleandepsmap, p - installed->start))
        continue;
      queue_empty(&q);
      /* find updaters */
      if (specialupdaters && (d = specialupdaters[p - installed->start]) != 0)
        {
          while ((p2 = pool->whatprovidesdata[d++]) != 0)
            if (solv->decisionmap[p2] >= 0)
              queue_push(&q, p2);
        }
      else
        {
          Rule *r = solv->rules + solv->updaterules + (p - installed->start);
          if (r->p)
            {
              FOR_RULELITERALS(p2, pp, r)
                if (solv->decisionmap[p2] >= 0)
                  queue_push(&q, p2);
            }
        }
      if (q.count && solv->update_targets && solv->update_targets->elements[p - installed->start])
        prune_to_update_targets(solv, solv->update_targets->elements + solv->update_targets->elements[p - installed->start], &q);
      /* mark all elements in dq that are in the updaters list */
      dq->elements[i] = -p;
      for (j = 0; j < dq->count; j++)
        {
          p = dq->elements[j];
          if (p < 0)
            continue;
          for (k = 0; k < q.count; k++)
            if (q.elements[k] == p)
              {
                dq->elements[j] = -p;
                break;
              }
        }
    }
  /* now prune to marked elements */
  for (i = j = 0; i < dq->count; i++)
    if ((p = dq->elements[i]) < 0)
      dq->elements[j++] = -p;
  dq->count = j;
  queue_free(&q);
}

static int
resolve_dependencies(Solver *solv, int level, int disablerules, Queue *dq)
{
  Pool *pool = solv->pool;
  int i, j, n;
  int postponed;
  Rule *r;
  int origlevel = level;
  Id p, *dp;

  /*
   * decide
   */
  POOL_DEBUG(SOLV_DEBUG_POLICY, "deciding unresolved rules\n");
  postponed = 0;
  for (i = 1, n = 1; ; i++, n++)
    {
      if (n >= solv->nrules)
        {
          if (postponed <= 0)
            break;
          i = postponed;
          postponed = -1;
          n = 1;
        }
      if (i == solv->nrules)
        i = 1;
      if (solv->focus_best && solv->do_extra_reordering && i >= solv->featurerules)
        continue;
      r = solv->rules + i;
      if (r->d < 0)             /* ignore disabled rules */
        continue;
      if (r->p < 0)             /* most common cases first */
        {
          if (r->d == 0 || solv->decisionmap[-r->p] <= 0)
            continue;
        }
      if (dq->count)
        queue_empty(dq);
      if (r->d == 0)
        {
          /* binary or unary rule */
          /* need two positive undecided literals, r->p already checked above */
          if (r->w2 <= 0)
            continue;
          if (solv->decisionmap[r->p] || solv->decisionmap[r->w2])
            continue;
          queue_push(dq, r->p);
          queue_push(dq, r->w2);
        }
      else
        {
          /* make sure that
           * all negative literals are installed
           * no positive literal is installed
           * i.e. the rule is not fulfilled and we
           * just need to decide on the positive literals
           * (decisionmap[-r->p] for the r->p < 0 case is already checked above)
           */
          if (r->p >= 0)
            {
              if (solv->decisionmap[r->p] > 0)
                continue;
              if (solv->decisionmap[r->p] == 0)
                queue_push(dq, r->p);
            }
          dp = pool->whatprovidesdata + r->d;
          while ((p = *dp++) != 0)
            {
              if (p < 0)
                {
                  if (solv->decisionmap[-p] <= 0)
                    break;
                }
              else
                {
                  if (solv->decisionmap[p] > 0)
                    break;
                  if (solv->decisionmap[p] == 0)
                    queue_push(dq, p);
                }
            }
          if (p)
            continue;
        }
      IF_POOLDEBUG (SOLV_DEBUG_PROPAGATE)
        {
          POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "unfulfilled ");
          solver_printruleclass(solv, SOLV_DEBUG_PROPAGATE, r);
        }
      /* dq->count < 2 cannot happen as this means that
       * the rule is unit */
      assert(dq->count > 1);

      /* prune to cleandeps packages */
      if (solv->cleandepsmap.size && solv->installed)
        {
          int cleandeps_update = 0;
          Repo *installed = solv->installed;
          for (j = 0; j < dq->count; j++)
            if (pool->solvables[dq->elements[j]].repo == installed && MAPTST(&solv->cleandepsmap, dq->elements[j] - installed->start))
              {
                if (solv->updatemap_all || (solv->updatemap.size && MAPTST(&solv->updatemap, dq->elements[j] - installed->start)))
                  {
                    cleandeps_update = 1;               /* cleandeps package is marked for update */
                    continue;
                  }
                break;
              }
          if (j < dq->count)
            {
              dq->elements[0] = dq->elements[j];
              queue_truncate(dq, 1);
            }
          else if (cleandeps_update)
            do_cleandeps_update_filter(solv, dq);       /* special update filter */
        }

      if (dq->count > 1 && postponed >= 0)
        {
          policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE_NOREORDER);
          if (dq->count > 1)
            {
              if (!postponed)
                postponed = i;
              continue;
            }
        }

      level = selectandinstall(solv, level, dq, disablerules, r - solv->rules, SOLVER_REASON_RESOLVE);
      if (level < origlevel)
        break;          /* trouble */
      /* something changed, so look at all rules again */
      n = 0;
    }
  return level;
}


#ifdef ENABLE_COMPLEX_DEPS

static void
add_complex_recommends(Solver *solv, Id rec, Queue *dq, Map *dqmap)
{
  Pool *pool = solv->pool;
  int oldcnt = dq->count;
  int cutcnt, blkcnt;
  Id p;
  int i, j;

#if 0
  printf("ADD_COMPLEX_RECOMMENDS %s\n", pool_dep2str(pool, rec));
#endif
  i = pool_normalize_complex_dep(pool, rec, dq, CPLXDEPS_EXPAND);
  if (i == 0 || i == 1)
    return;
  cutcnt = dq->count;
  for (i = oldcnt; i < cutcnt; i++)
    {
      blkcnt = dq->count;
      for (; (p = dq->elements[i]) != 0; i++)
        {
          if (p < 0)
            {
              if (solv->decisionmap[-p] <= 0)
                break;
              continue;
            }
          if (solv->decisionmap[p] > 0)
            {
              queue_truncate(dq, blkcnt);
              break;
            }
          if (dqmap)
            {
              if (!MAPTST(dqmap, p))
                continue;
            }
          else
            {
              if (solv->decisionmap[p] < 0)
                continue;
              if (solv->process_orphans && solv->installed && pool->solvables[p].repo == solv->installed && (solv->droporphanedmap_all || (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))))
                continue;
            }
          queue_push(dq, p);
        }
      while (dq->elements[i])
        i++;
    }
  queue_deleten(dq, oldcnt, cutcnt - oldcnt);
  /* unify */
  if (dq->count != oldcnt)
    {
      for (j = oldcnt; j < dq->count; j++)
        {
          p = dq->elements[j];
          for (i = 0; i < j; i++)
            if (dq->elements[i] == p)
              {
                dq->elements[j] = 0;
                break;
              }
        }
      for (i = j = oldcnt; j < dq->count; j++)
        if (dq->elements[j])
          dq->elements[i++] = dq->elements[j];
      queue_truncate(dq, i);
    }
#if 0
  printf("RETURN:\n");
  for (i = oldcnt; i < dq->count; i++)
    printf("  - %s\n", pool_solvid2str(pool, dq->elements[i]));
#endif
}

static void
do_complex_recommendations(Solver *solv, Id rec, Map *m, int noselected)
{
  Pool *pool = solv->pool;
  Queue dq;
  Id p;
  int i, blk;

#if 0
  printf("DO_COMPLEX_RECOMMENDATIONS %s\n", pool_dep2str(pool, rec));
#endif
  queue_init(&dq);
  i = pool_normalize_complex_dep(pool, rec, &dq, CPLXDEPS_EXPAND);
  if (i == 0 || i == 1)
    {
      queue_free(&dq);
      return;
    }
  for (i = 0; i < dq.count; i++)
    {
      blk = i;
      for (; (p = dq.elements[i]) != 0; i++)
        {
          if (p < 0)
            {
              if (solv->decisionmap[-p] <= 0)
                break;
              continue;
            }
          if (solv->decisionmap[p] > 0)
            {
              if (noselected)
                break;
              MAPSET(m, p);
              for (i++; (p = dq.elements[i]) != 0; i++)
                if (p > 0 && solv->decisionmap[p] > 0)
                  MAPSET(m, p);
              p = 1;
              break;
            }
        }
      if (!p)
        {
          for (i = blk; (p = dq.elements[i]) != 0; i++)
            if (p > 0)
              MAPSET(m, p);
        }
      while (dq.elements[i])
        i++;
    }
  queue_free(&dq);
}

#endif

static void
prune_disfavored(Solver *solv, Queue *plist)
{
  int i, j;
  for (i = j = 0; i < plist->count; i++)
    {
      Id p = plist->elements[i];
      if (solv->favormap[p] >= 0)
        plist->elements[j++] = p;
    }
  if (i != j)
    queue_truncate(plist, j);
}

static int
resolve_weak(Solver *solv, int level, int disablerules, Queue *dq, Queue *dqs, int *rerunp)
{
  Pool *pool = solv->pool;
  int i, j, qcount;
  int olevel;
  Solvable *s;
  Map dqmap;
  int decisioncount;
  Id p;

  POOL_DEBUG(SOLV_DEBUG_POLICY, "installing recommended packages\n");
  if (dq->count)
    queue_empty(dq);    /* recommended packages */
  if (dqs->count)
    queue_empty(dqs);   /* supplemented packages */
  for (i = 1; i < pool->nsolvables; i++)
    {
      if (solv->decisionmap[i] < 0)
        continue;
      s = pool->solvables + i;
      if (solv->decisionmap[i] > 0)
        {
          /* installed, check for recommends */
          Id *recp, rec, pp, p;
          if (!solv->addalreadyrecommended && s->repo == solv->installed)
            continue;
          if (s->recommends)
            {
              recp = s->repo->idarraydata + s->recommends;
              while ((rec = *recp++) != 0)
                {
                  /* cheat: we just look if there is REL_NAMESPACE in the dep */
                  if (solv->only_namespace_recommended && !solver_is_namespace_dep(solv, rec))
                    continue;
#ifdef ENABLE_COMPLEX_DEPS
                  if (pool_is_complex_dep(pool, rec))
                    {
                      add_complex_recommends(solv, rec, dq, 0);
                      continue;
                    }
#endif
                  qcount = dq->count;
                  FOR_PROVIDES(p, pp, rec)
                    {
                      if (solv->decisionmap[p] > 0)
                        {
                          dq->count = qcount;
                          break;
                        }
                      else if (solv->decisionmap[p] == 0)
                        {
                          if (solv->process_orphans && solv->installed && pool->solvables[p].repo == solv->installed && (solv->droporphanedmap_all || (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))))
                            continue;
                          queue_pushunique(dq, p);
                        }
                    }
                }
            }
        }
      else
        {
          /* not yet installed, check if supplemented */
          if (!s->supplements)
            continue;
          if (!pool_installable(pool, s))
            continue;
          if (!solver_is_supplementing(solv, s))
            continue;
          if (solv->process_orphans && solv->installed && s->repo == solv->installed && (solv->droporphanedmap_all || (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, i - solv->installed->start))))
            continue;
          if (solv->havedisfavored && solv->favormap[i] < 0)
            continue;   /* disfavored supplements, do not install */
          queue_push(dqs, i);
        }
    }

  /* filter out disfavored recommended packages */
  if (dq->count && solv->havedisfavored)
    prune_disfavored(solv, dq);

  /* filter out all packages obsoleted by installed packages */
  /* this is no longer needed if we have (and trust) reverse obsoletes */
  if ((dqs->count || dq->count) && solv->installed)
    {
      Map obsmap;
      Id obs, *obsp, po, ppo;

      map_init(&obsmap, pool->nsolvables);
      for (p = solv->installed->start; p < solv->installed->end; p++)
        {
          s = pool->solvables + p;
          if (s->repo != solv->installed || !s->obsoletes)
            continue;
          if (solv->decisionmap[p] <= 0)
            continue;
          if (!solv->keepexplicitobsoletes && solv->multiversion.size && MAPTST(&solv->multiversion, p))
            continue;
          obsp = s->repo->idarraydata + s->obsoletes;
          /* foreach obsoletes */
          while ((obs = *obsp++) != 0)
            FOR_PROVIDES(po, ppo, obs)
              {
                Solvable *pos = pool->solvables + po;
                if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, pos, obs))
                  continue;
                if (pool->obsoleteusescolors && !pool_colormatch(pool, s, pos))
                  continue;
                MAPSET(&obsmap, po);
              }
        }
      for (i = j = 0; i < dqs->count; i++)
        if (!MAPTST(&obsmap, dqs->elements[i]))
          dqs->elements[j++] = dqs->elements[i];
      dqs->count = j;
      for (i = j = 0; i < dq->count; i++)
        if (!MAPTST(&obsmap, dq->elements[i]))
          dq->elements[j++] = dq->elements[i];
      dq->count = j;
      map_free(&obsmap);
    }

  /* filter out all already supplemented packages if requested */
  if ((!solv->addalreadyrecommended || solv->only_namespace_recommended) && dqs->count)
    {
      /* filter out old supplements */
      for (i = j = 0; i < dqs->count; i++)
        {
          p = dqs->elements[i];
          s = pool->solvables + p;
          if (s->supplements && solver_is_supplementing_alreadyinstalled(solv, s))
            dqs->elements[j++] = p;
        }
      dqs->count = j;
    }

  /* multiversion doesn't mix well with supplements.
   * filter supplemented packages where we already decided
   * to install a different version (see bnc#501088) */
  if (dqs->count && solv->multiversion.size)
    {
      for (i = j = 0; i < dqs->count; i++)
        {
          p = dqs->elements[i];
          if (MAPTST(&solv->multiversion, p))
            {
              Id p2, pp2;
              s = pool->solvables + p;
              FOR_PROVIDES(p2, pp2, s->name)
                if (solv->decisionmap[p2] > 0 && pool->solvables[p2].name == s->name)
                  break;
              if (p2)
                continue;       /* ignore this package */
            }
          dqs->elements[j++] = p;
        }
      dqs->count = j;
    }

  /* implicitobsoleteusescolors doesn't mix well with supplements.
   * filter supplemented packages where we already decided
   * to install a different architecture */
  if (dqs->count && pool->implicitobsoleteusescolors)
    {
      for (i = j = 0; i < dqs->count; i++)
        {
          Id p2, pp2;
          p = dqs->elements[i];
          s = pool->solvables + p;
          FOR_PROVIDES(p2, pp2, s->name)
            if (solv->decisionmap[p2] > 0 && pool->solvables[p2].name == s->name && pool->solvables[p2].arch != s->arch)
              break;
          if (p2)
            continue;   /* ignore this package */
          dqs->elements[j++] = p;
        }
      dqs->count = j;
    }

  /* make dq contain both recommended and supplemented pkgs */
  if (dqs->count)
    {
      for (i = 0; i < dqs->count; i++)
        queue_pushunique(dq, dqs->elements[i]);
    }

  if (!dq->count)
    return level;
  *rerunp = 1;

  if (dq->count == 1)
    {
      /* simple case, just one package. no need to choose to best version */
      p = dq->elements[0];
      if (dqs->count)
        POOL_DEBUG(SOLV_DEBUG_POLICY, "installing supplemented %s\n", pool_solvid2str(pool, p));
      else
        POOL_DEBUG(SOLV_DEBUG_POLICY, "installing recommended %s\n", pool_solvid2str(pool, p));
      return setpropagatelearn(solv, level, p, 0, 0, SOLVER_REASON_WEAKDEP);
    }

  /* filter packages, this gives us the best versions */
  policy_filter_unwanted(solv, dq, POLICY_MODE_RECOMMEND);

  /* create map of result */
  map_init(&dqmap, pool->nsolvables);
  for (i = 0; i < dq->count; i++)
    MAPSET(&dqmap, dq->elements[i]);

  /* prune dqs so that it only contains the best versions */
  for (i = j = 0; i < dqs->count; i++)
    {
      p = dqs->elements[i];
      if (MAPTST(&dqmap, p))
        dqs->elements[j++] = p;
    }
  dqs->count = j;

  /* install all supplemented packages, but order first */
  if (dqs->count > 1)
    policy_filter_unwanted(solv, dqs, POLICY_MODE_SUPPLEMENT);
  decisioncount = solv->decisionq.count;
  for (i = 0; i < dqs->count; i++)
    {
      p = dqs->elements[i];
      if (solv->decisionmap[p])
        continue;
      POOL_DEBUG(SOLV_DEBUG_POLICY, "installing supplemented %s\n", pool_solvid2str(pool, p));
      olevel = level;
      level = setpropagatelearn(solv, level, p, 0, 0, SOLVER_REASON_WEAKDEP);
      if (level <= olevel)
        break;
    }
  if (i < dqs->count || solv->decisionq.count < decisioncount)
    {
      map_free(&dqmap);
      return level;
    }

  /* install all recommended packages */
  /* more work as we want to created branches if multiple
   * choices are valid */
  for (i = 0; i < decisioncount; i++)
    {
      Id rec, *recp, pp;
      p = solv->decisionq.elements[i];
      if (p < 0)
        continue;
      s = pool->solvables + p;
      if (!s->repo || (!solv->addalreadyrecommended && s->repo == solv->installed))
        continue;
      if (!s->recommends)
        continue;
      recp = s->repo->idarraydata + s->recommends;
      while ((rec = *recp++) != 0)
        {
          queue_empty(dq);
#ifdef ENABLE_COMPLEX_DEPS
          if (pool_is_complex_dep(pool, rec))
              add_complex_recommends(solv, rec, dq, &dqmap);
          else
#endif
          FOR_PROVIDES(p, pp, rec)
            {
              if (solv->decisionmap[p] > 0)
                {
                  dq->count = 0;
                  break;
                }
              else if (solv->decisionmap[p] == 0 && MAPTST(&dqmap, p))
                queue_push(dq, p);
            }
          if (!dq->count)
            continue;
          if (dq->count > 1)
            policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
          /* if we have multiple candidates we open a branch */
          if (dq->count > 1)
            createbranch(solv, level, dq, s - pool->solvables, rec);
          p = dq->elements[0];
          POOL_DEBUG(SOLV_DEBUG_POLICY, "installing recommended %s\n", pool_solvid2str(pool, p));
          olevel = level;
          level = setpropagatelearn(solv, level, p, 0, 0, SOLVER_REASON_WEAKDEP);
          if (level <= olevel || solv->decisionq.count < decisioncount)
            break;      /* we had to revert some decisions */
        }
      if (rec)
        break;  /* had a problem above, quit loop */
    }
  map_free(&dqmap);
  return level;
}

static int
resolve_cleandeps(Solver *solv, int level, int disablerules, int *rerunp)
{
  Pool *pool = solv->pool;
  Repo *installed = solv->installed;
  int olevel;
  Id p;
  Solvable *s;

  if (!installed || !solv->cleandepsmap.size)
    return level;
  POOL_DEBUG(SOLV_DEBUG_SOLVER, "deciding cleandeps packages\n");
  for (p = installed->start; p < installed->end; p++)
    {
      s = pool->solvables + p;
      if (s->repo != installed)
        continue;
      if (solv->decisionmap[p] != 0 || !MAPTST(&solv->cleandepsmap, p - installed->start))
        continue;
      POOL_DEBUG(SOLV_DEBUG_POLICY, "cleandeps erasing %s\n", pool_solvid2str(pool, p));
      olevel = level;
      level = setpropagatelearn(solv, level, -p, 0, 0, SOLVER_REASON_CLEANDEPS_ERASE);
      if (level < olevel)
        break;
    }
  if (p < installed->end)
    *rerunp = 1;
  return level;
}

static int
resolve_orphaned(Solver *solv, int level, int disablerules, Queue *dq, int *rerunp)
{
  Pool *pool = solv->pool;
  int i;
  Id p;
  int installedone = 0;
  int olevel;

  /* let's see if we can install some unsupported package */
  POOL_DEBUG(SOLV_DEBUG_SOLVER, "deciding orphaned packages\n");
  for (i = 0; i < solv->orphaned.count; i++)
    {
      p = solv->orphaned.elements[i];
      if (solv->decisionmap[p])
        continue;       /* already decided */
      if (solv->droporphanedmap_all)
        continue;
      if (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))
        continue;
      POOL_DEBUG(SOLV_DEBUG_SOLVER, "keeping orphaned %s\n", pool_solvid2str(pool, p));
      olevel = level;
      level = setpropagatelearn(solv, level, p, 0, 0, SOLVER_REASON_RESOLVE_ORPHAN);
      installedone = 1;
      if (level < olevel)
        break;
    }
  if (installedone || i < solv->orphaned.count)
    {
      *rerunp = 1;
      return level;
    }
  for (i = 0; i < solv->orphaned.count; i++)
    {
      p = solv->orphaned.elements[i];
      if (solv->decisionmap[p])
        continue;       /* already decided */
      POOL_DEBUG(SOLV_DEBUG_SOLVER, "removing orphaned %s\n", pool_solvid2str(pool, p));
      olevel = level;
      level = setpropagatelearn(solv, level, -p, 0, 0, SOLVER_REASON_RESOLVE_ORPHAN);
      if (level < olevel)
        {
          *rerunp = 1;
          return level;
        }
    }
  if (solv->brokenorphanrules)
    {
      solver_check_brokenorphanrules(solv, dq);
      if (dq->count)
        {
          policy_filter_unwanted(solv, dq, POLICY_MODE_CHOOSE);
          for (i = 0; i < dq->count; i++)
            {
              p = dq->elements[i];
              POOL_DEBUG(SOLV_DEBUG_POLICY, "installing orphaned dep %s\n", pool_solvid2str(pool, p));
              olevel = level;
              level = setpropagatelearn(solv, level, p, 0, 0, SOLVER_REASON_RESOLVE_ORPHAN);
              if (level < olevel)
                break;
            }
          *rerunp = 1;
          return level;
        }
    }
  return level;
}

/*-------------------------------------------------------------------
 *
 * solver_run_sat
 *
 * all rules have been set up, now actually run the solver
 *
 */

void
solver_run_sat(Solver *solv, int disablerules, int doweak)
{
  Queue dq;             /* local decisionqueue */
  Queue dqs;            /* local decisionqueue for supplements */
  int systemlevel;
  int level, olevel;
  Rule *r;
  int i;
  Solvable *s;
  Pool *pool = solv->pool;
  Id p;
  int minimizationsteps;

  IF_POOLDEBUG (SOLV_DEBUG_RULE_CREATION)
    {
      POOL_DEBUG (SOLV_DEBUG_RULE_CREATION, "number of rules: %d\n", solv->nrules);
      for (i = 1; i < solv->nrules; i++)
        solver_printruleclass(solv, SOLV_DEBUG_RULE_CREATION, solv->rules + i);
    }

  /* start SAT algorithm */
  level = 0;
  systemlevel = level + 1;
  POOL_DEBUG(SOLV_DEBUG_SOLVER, "solving...\n");

  queue_init(&dq);
  queue_init(&dqs);
  solv->installedpos = 0;
  solv->do_extra_reordering = 0;

  /*
   * here's the main loop:
   * 1) decide assertion rules and propagate
   * 2) fulfill jobs
   * 3) try to keep installed packages
   * 4) fulfill all unresolved rules
   * 5) install recommended packages
   * 6) minimalize solution if we had choices
   * if we encounter a problem, we rewind to a safe level and restart
   * with step 1
   */

  minimizationsteps = 0;
  for (;;)
    {
      /*
       * initial propagation of the assertions
       */
      if (level <= 0)
        {
          if (level < 0)
            break;
          level = makeruledecisions(solv, disablerules);
          if (level < 0)
            break;
          POOL_DEBUG(SOLV_DEBUG_PROPAGATE, "initial propagate (propagate_index: %d;  size decisionq: %d)...\n", solv->propagate_index, solv->decisionq.count);
          if ((r = propagate(solv, level)) != 0)
            {
              level = analyze_unsolvable(solv, r, disablerules);
              continue;
            }
          systemlevel = level + 1;
        }

      /*
       * resolve jobs first (unless focus_installed is set)
       */
     if (level < systemlevel && !solv->focus_installed)
        {
          if (solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
            solv->do_extra_reordering = 1;
          olevel = level;
          level = resolve_jobrules(solv, level, disablerules, &dq);
          solv->do_extra_reordering = 0;
          if (level < olevel)
            continue;
          systemlevel = level + 1;
        }

      /* resolve job dependencies in the focus_best case */
      if (level < systemlevel && solv->focus_best && !solv->focus_installed && solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
        {
          solv->do_extra_reordering = 1;
          olevel = level;
          level = resolve_dependencies(solv, level, disablerules, &dq);
          solv->do_extra_reordering = 0;
          if (level < olevel)
            continue;           /* start over */
          systemlevel = level + 1;
        }

      /*
       * installed packages
       */
      if (level < systemlevel && solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
        {
          olevel = level;
          level = resolve_installed(solv, level, disablerules, &dq);
          if (level < olevel)
            continue;
          systemlevel = level + 1;
        }

     /* resolve jobs in focus_installed case */
     if (level < systemlevel && solv->focus_installed)
        {
          olevel = level;
          level = resolve_jobrules(solv, level, disablerules, &dq);
          if (level < olevel)
            continue;
          systemlevel = level + 1;
        }

      if (level < systemlevel)
        systemlevel = level;

      /* resolve all dependencies */
      olevel = level;
      level = resolve_dependencies(solv, level, disablerules, &dq);
      if (level < olevel)
        continue;               /* start over */

      /* decide leftover cleandeps packages */
      if (solv->cleandepsmap.size && solv->installed)
        {
          int rerun = 0;
          level = resolve_cleandeps(solv, level, disablerules, &rerun);
          if (rerun)
            continue;
        }

      /* at this point we have a consistent system. now do the extras... */

      if (doweak)
        {
          int rerun = 0;
          level = resolve_weak(solv, level, disablerules, &dq, &dqs, &rerun);
          if (rerun)
            continue;
        }

      if (solv->installed && (solv->orphaned.count || solv->brokenorphanrules))
        {
          int rerun = 0;
          level = resolve_orphaned(solv, level, disablerules, &dq, &rerun);
          if (rerun)
            continue;
        }

     /* one final pass to make sure we decided all installed packages */
      if (solv->installed)
        {
          for (p = solv->installed->start; p < solv->installed->end; p++)
            {
              if (solv->decisionmap[p])
                continue;       /* already decided */
              s = pool->solvables + p;
              if (s->repo != solv->installed)
                continue;
              POOL_DEBUG(SOLV_DEBUG_SOLVER, "removing unwanted %s\n", pool_solvid2str(pool, p));
              olevel = level;
              level = setpropagatelearn(solv, level, -p, 0, 0, SOLVER_REASON_CLEANDEPS_ERASE);
              if (level < olevel)
                break;
            }
          if (p < solv->installed->end)
            continue;           /* back to main loop */
        }

      if (solv->installed && solv->cleandepsmap.size && solver_check_cleandeps_mistakes(solv))
        {
          solver_reset(solv);
          level = 0;    /* restart from scratch */
          continue;
        }

      if (solv->solution_callback)
        {
          solv->solution_callback(solv, solv->solution_callback_data);
          if (solv->branches.count)
            {
              int l, endi = 0;
              p = l = 0;
              for (i = solv->branches.count - 1; i >= 0; i--)
                {
                  p = solv->branches.elements[i];
                  if (p > 0 && !l)
                    {
                      endi = i + 1;
                      l = p;
                      i -= 3;   /* skip: p data count */
                    }
                  else if (p > 0)
                    break;
                  else if (p < 0)
                    l = 0;
                }
              if (i >= 0)
                {
                  while (i > 0 && solv->branches.elements[i - 1] > 0)
                    i--;
                  level = takebranch(solv, i, endi, "branching", disablerules);
                  continue;
                }
            }
          /* all branches done, we're finally finished */
          break;
        }

      /* auto-minimization step */
      if (solv->branches.count)
        {
          int endi, lasti = -1, lastiend = -1;
          if (solv->recommends_index < solv->decisionq.count)
            policy_update_recommendsmap(solv);
          for (endi = solv->branches.count; endi > 0;)
            {
              int l, lastsi = -1, starti = endi - solv->branches.elements[endi - 2];
              l = solv->branches.elements[endi - 1];
              for (i = starti; i < endi - 4; i++)
                {
                  p = solv->branches.elements[i];
                  if (p <= 0)
                    continue;
                  if (solv->decisionmap[p] > l)
                    {
                      lasti = i;
                      lastiend = endi;
                      lastsi = -1;
                      break;
                    }
                  if (solv->havedisfavored && solv->favormap[p] < 0)
                    continue;
                  if (lastsi < 0 && (MAPTST(&solv->recommendsmap, p) || solver_is_supplementing(solv, pool->solvables + p)))
                    lastsi = i;
                }
              if (lastsi >= 0)
                {
                  /* we have a recommended package that could not be installed */
                  /* find current selection and take new one if it is not recommended */
                  for (i = starti; i < endi - 4; i++)
                    {
                      p = -solv->branches.elements[i];
                      if (p <= 0 || solv->decisionmap[p] != l + 1)
                        continue;
                      if (solv->favormap && solv->favormap[p] > solv->favormap[solv->branches.elements[lastsi]])
                        continue;       /* current selection is more favored */
                      if (!(MAPTST(&solv->recommendsmap, p) || solver_is_supplementing(solv, pool->solvables + p)))
                        {
                          lasti = lastsi;
                          lastiend = endi;
                          break;
                        }
                    }
                }
              endi = starti;
            }
          if (lasti >= 0)
            {
              minimizationsteps++;
              level = takebranch(solv, lasti, lastiend, "minimizing", disablerules);
              continue;         /* back to main loop */
            }
        }
      /* no minimization found, we're finally finished! */
      break;
    }
  assert(level == -1 || level + 1 == solv->decisionq_reason.count);

  POOL_DEBUG(SOLV_DEBUG_STATS, "solver statistics: %d learned rules, %d unsolvable, %d minimization steps\n", solv->stats_learned, solv->stats_unsolvable, minimizationsteps);

  POOL_DEBUG(SOLV_DEBUG_STATS, "done solving.\n\n");
  queue_free(&dq);
  queue_free(&dqs);
#if 0
  solver_printdecisionq(solv, SOLV_DEBUG_RESULT);
#endif
}


/*-------------------------------------------------------------------
 *
 * remove disabled conflicts
 *
 * purpose: update the decisionmap after some rules were disabled.
 * this is used to calculate the suggested/recommended package list.
 * Also returns a "removed" list to undo the discisionmap changes.
 */

static void
removedisabledconflicts(Solver *solv, Queue *removed)
{
  Pool *pool = solv->pool;
  int i, n;
  Id p, why, *dp;
  Id new;
  Rule *r;
  Id *decisionmap = solv->decisionmap;

  queue_empty(removed);
  for (i = 0; i < solv->decisionq.count; i++)
    {
      p = solv->decisionq.elements[i];
      if (p > 0)
        continue;       /* conflicts only, please */
      why = solv->decisionq_why.elements[i];
      if (why == 0)
        {
          /* no rule involved, must be a orphan package drop */
          continue;
        }
      /* we never do conflicts on free decisions, so there
       * must have been an unit rule */
      assert(why > 0);
      r = solv->rules + why;
      if (r->d < 0 && decisionmap[-p])
        {
          /* rule is now disabled, remove from decisionmap */
          POOL_DEBUG(SOLV_DEBUG_SOLVER, "removing conflict for package %s[%d]\n", pool_solvid2str(pool, -p), -p);
          queue_push(removed, -p);
          queue_push(removed, decisionmap[-p]);
          decisionmap[-p] = 0;
        }
    }
  if (!removed->count)
    return;
  /* we removed some confliced packages. some of them might still
   * be in conflict, so search for unit rules and re-conflict */
  new = 0;
  for (i = n = 1, r = solv->rules + i; n < solv->nrules; i++, r++, n++)
    {
      if (i == solv->nrules)
        {
          i = 1;
          r = solv->rules + i;
        }
      if (r->d < 0)
        continue;
      if (!r->w2)
        {
          if (r->p < 0 && !decisionmap[-r->p])
            new = r->p;
        }
      else if (!r->d)
        {
          /* binary rule */
          if (r->p < 0 && decisionmap[-r->p] == 0 && DECISIONMAP_FALSE(r->w2))
            new = r->p;
          else if (r->w2 < 0 && decisionmap[-r->w2] == 0 && DECISIONMAP_FALSE(r->p))
            new = r->w2;
        }
      else
        {
          if (r->p < 0 && decisionmap[-r->p] == 0)
            new = r->p;
          if (new || DECISIONMAP_FALSE(r->p))
            {
              dp = pool->whatprovidesdata + r->d;
              while ((p = *dp++) != 0)
                {
                  if (new && p == new)
                    continue;
                  if (p < 0 && decisionmap[-p] == 0)
                    {
                      if (new)
                        {
                          new = 0;
                          break;
                        }
                      new = p;
                    }
                  else if (!DECISIONMAP_FALSE(p))
                    {
                      new = 0;
                      break;
                    }
                }
            }
        }
      if (new)
        {
          POOL_DEBUG(SOLV_DEBUG_SOLVER, "re-conflicting package %s[%d]\n", pool_solvid2str(pool, -new), -new);
          decisionmap[-new] = -1;
          new = 0;
          n = 0;        /* redo all rules */
        }
    }
}

static inline void
undo_removedisabledconflicts(Solver *solv, Queue *removed)
{
  int i;
  for (i = 0; i < removed->count; i += 2)
    solv->decisionmap[removed->elements[i]] = removed->elements[i + 1];
}


/*-------------------------------------------------------------------
 *
 * weaken solvable dependencies
 */

static void
weaken_solvable_deps(Solver *solv, Id p)
{
  int i;
  Rule *r;

  for (i = 1, r = solv->rules + i; i < solv->pkgrules_end; i++, r++)
    {
      if (r->p != -p)
        continue;
      if ((r->d == 0 || r->d == -1) && r->w2 < 0)
        continue;       /* conflict */
      queue_push(&solv->weakruleq, i);
    }
}


/********************************************************************/
/* main() */


void
solver_calculate_multiversionmap(Pool *pool, Queue *job, Map *multiversionmap)
{
  int i;
  Id how, what, select;
  Id p, pp;
  for (i = 0; i < job->count; i += 2)
    {
      how = job->elements[i];
      if ((how & SOLVER_JOBMASK) != SOLVER_MULTIVERSION)
        continue;
      what = job->elements[i + 1];
      select = how & SOLVER_SELECTMASK;
      if (!multiversionmap->size)
        map_grow(multiversionmap, pool->nsolvables);
      if (select == SOLVER_SOLVABLE_ALL)
        {
          FOR_POOL_SOLVABLES(p)
            MAPSET(multiversionmap, p);
        }
      else if (select == SOLVER_SOLVABLE_REPO)
        {
          Solvable *s;
          Repo *repo = pool_id2repo(pool, what);
          if (repo)
            {
              FOR_REPO_SOLVABLES(repo, p, s)
                MAPSET(multiversionmap, p);
            }
        }
      FOR_JOB_SELECT(p, pp, select, what)
        MAPSET(multiversionmap, p);
    }
}

void
solver_calculate_noobsmap(Pool *pool, Queue *job, Map *multiversionmap)
{
  solver_calculate_multiversionmap(pool, job, multiversionmap);
}

/*
 * add a rule created by a job, record job number and weak flag
 */
static inline void
solver_addjobrule(Solver *solv, Id p, Id p2, Id d, Id job, int weak)
{
  solver_addrule(solv, p, p2, d);
  queue_push(&solv->ruletojob, job);
  if (weak)
    queue_push(&solv->weakruleq, solv->nrules - 1);
}

static inline void
add_cleandeps_updatepkg(Solver *solv, Id p)
{
  if (!solv->cleandeps_updatepkgs)
    {
      solv->cleandeps_updatepkgs = solv_calloc(1, sizeof(Queue));
      queue_init(solv->cleandeps_updatepkgs);
    }
  queue_pushunique(solv->cleandeps_updatepkgs, p);
}

static void
add_update_target(Solver *solv, Id p, Id how)
{
  Pool *pool = solv->pool;
  Solvable *s = pool->solvables + p;
  Repo *installed = solv->installed;
  Id pi, pip, identicalp;
  int startcnt, endcnt;

  if (!solv->update_targets)
    {
      solv->update_targets = solv_calloc(1, sizeof(Queue));
      queue_init(solv->update_targets);
    }
  if (s->repo == installed)
    {
      queue_push2(solv->update_targets, p, p);
      return;
    }
  identicalp = 0;
  startcnt = solv->update_targets->count;
  FOR_PROVIDES(pi, pip, s->name)
    {
      Solvable *si = pool->solvables + pi;
      if (si->repo != installed || si->name != s->name)
        continue;
      if (how & SOLVER_FORCEBEST)
        {
          if (!solv->bestupdatemap.size)
            map_grow(&solv->bestupdatemap, installed->end - installed->start);
          MAPSET(&solv->bestupdatemap, pi - installed->start);
        }
      if (how & SOLVER_CLEANDEPS)
        add_cleandeps_updatepkg(solv, pi);
      queue_push2(solv->update_targets, pi, p);
      /* remember an installed package that is identical to p */
      if (s->evr == si->evr && solvable_identical(s, si))
        identicalp = pi;
    }
  if (s->obsoletes)
    {
      Id obs, *obsp = s->repo->idarraydata + s->obsoletes;
      while ((obs = *obsp++) != 0)
        {
          FOR_PROVIDES(pi, pip, obs)
            {
              Solvable *si = pool->solvables + pi;
              if (si->repo != installed)
                continue;
              if (si->name == s->name)
                continue;       /* already handled above */
              if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, si, obs))
                continue;
              if (pool->obsoleteusescolors && !pool_colormatch(pool, s, si))
                continue;
              if (how & SOLVER_FORCEBEST)
                {
                  if (!solv->bestupdatemap.size)
                    map_grow(&solv->bestupdatemap, installed->end - installed->start);
                  MAPSET(&solv->bestupdatemap, pi - installed->start);
                }
              if (how & SOLVER_CLEANDEPS)
                add_cleandeps_updatepkg(solv, pi);
              queue_push2(solv->update_targets, pi, p);
            }
        }
    }
  /* also allow upgrading to an identical installed package */
  if (identicalp)
    {
      for (endcnt = solv->update_targets->count; startcnt < endcnt; startcnt += 2)
        queue_push2(solv->update_targets, solv->update_targets->elements[startcnt], identicalp);
    }
}

static int
transform_update_targets_sortfn(const void *ap, const void *bp, void *dp)
{
  const Id *a = ap;
  const Id *b = bp;
  if (a[0] - b[0])
    return a[0] - b[0];
  return a[1] - b[1];
}

static void
transform_update_targets(Solver *solv)
{
  Repo *installed = solv->installed;
  Queue *update_targets = solv->update_targets;
  int i, j;
  Id p, q, lastp, lastq;

  if (!update_targets->count)
    {
      queue_free(update_targets);
      solv->update_targets = solv_free(update_targets);
      return;
    }
  if (update_targets->count > 2)
    solv_sort(update_targets->elements, update_targets->count >> 1, 2 * sizeof(Id), transform_update_targets_sortfn, solv);
  queue_insertn(update_targets, 0, installed->end - installed->start, 0);
  lastp = lastq = 0;
  for (i = j = installed->end - installed->start; i < update_targets->count; i += 2)
    {
      if ((p = update_targets->elements[i]) != lastp)
        {
          if (!solv->updatemap.size)
            map_grow(&solv->updatemap, installed->end - installed->start);
          MAPSET(&solv->updatemap, p - installed->start);
          update_targets->elements[j++] = 0;                    /* finish old set */
          update_targets->elements[p - installed->start] = j;   /* start new set */
          lastp = p;
          lastq = 0;
        }
      if ((q = update_targets->elements[i + 1]) != lastq)
        {
          update_targets->elements[j++] = q;
          lastq = q;
        }
    }
  queue_truncate(update_targets, j);
  queue_push(update_targets, 0);        /* finish last set */
}


static void
addedmap2deduceq(Solver *solv, Map *addedmap)
{
  Pool *pool = solv->pool;
  int i, j;
  Id p;
  Rule *r;

  queue_empty(&solv->addedmap_deduceq);
  for (i = 2, j = solv->pkgrules_end - 1; i < pool->nsolvables && j > 0; j--)
    {
      r = solv->rules + j;
      if (r->p >= 0)
        continue;
      if ((r->d == 0 || r->d == -1) && r->w2 < 0)
        continue;
      p = -r->p;
      if (!MAPTST(addedmap, p))
        {
          /* should never happen, but... */
          if (!solv->addedmap_deduceq.count || solv->addedmap_deduceq.elements[solv->addedmap_deduceq.count - 1] != -p)
            queue_push(&solv->addedmap_deduceq, -p);
          continue;
        }
      for (; i < p; i++)
        if (MAPTST(addedmap, i))
          queue_push(&solv->addedmap_deduceq, i);
      if (i == p)
        i++;
    }
  for (; i < pool->nsolvables; i++)
    if (MAPTST(addedmap, i))
      queue_push(&solv->addedmap_deduceq, i);
}

static void
deduceq2addedmap(Solver *solv, Map *addedmap)
{
  int j;
  Id p;
  Rule *r;
  for (j = solv->pkgrules_end - 1; j > 0; j--)
    {
      r = solv->rules + j;
      if (r->d < 0 && r->p)
        solver_enablerule(solv, r);
      if (r->p >= 0)
        continue;
      if ((r->d == 0 || r->d == -1) && r->w2 < 0)
        continue;
      p = -r->p;
      MAPSET(addedmap, p);
    }
  for (j = 0; j < solv->addedmap_deduceq.count; j++)
    {
      p = solv->addedmap_deduceq.elements[j];
      if (p > 0)
        MAPSET(addedmap, p);
      else
        MAPCLR(addedmap, p);
    }
}

#ifdef ENABLE_COMPLEX_DEPS
static int
add_complex_jobrules(Solver *solv, Id dep, int flags, int jobidx, int weak)
{
  Pool *pool = solv->pool;
  Queue bq;
  int i, j;

  queue_init(&bq);
  i = pool_normalize_complex_dep(pool, dep, &bq, flags | CPLXDEPS_EXPAND);
  if (i == 0 || i == 1)
    {
      queue_free(&bq);
      if (i == 0)
        solver_addjobrule(solv, -SYSTEMSOLVABLE, 0, 0, jobidx, weak);
      return 0;
    }
  for (i = 0; i < bq.count; i++)
    {
      if (!bq.elements[i])
        continue;
      for (j = 0; bq.elements[i + j + 1]; j++)
        ;
      if (j > 1)
        solver_addjobrule(solv, bq.elements[i], 0, pool_ids2whatprovides(pool, bq.elements + i + 1, j), jobidx, weak);
      else
        solver_addjobrule(solv, bq.elements[i], bq.elements[i + 1], 0, jobidx, weak);
      i += j + 1;
    }
  queue_free(&bq);
  return 1;
}
#endif

static void
setup_favormap(Solver *solv)
{
  Queue *job = &solv->job;
  Pool *pool = solv->pool;
  int i, idx;
  Id p, pp, how, what, select;

  solv_free(solv->favormap);
  solv->favormap = solv_calloc(pool->nsolvables, sizeof(Id));
  for (i = 0; i < job->count; i += 2)
    {
      how = job->elements[i];
      if ((how & SOLVER_JOBMASK) != SOLVER_FAVOR && (how & SOLVER_JOBMASK) != SOLVER_DISFAVOR)
        continue;
      what = job->elements[i + 1];
      select = how & SOLVER_SELECTMASK;
      idx = (how & SOLVER_JOBMASK) == SOLVER_FAVOR ? i + 1 : -(i + 1);
      if (select == SOLVER_SOLVABLE_REPO)
        {
          Repo *repo = pool_id2repo(pool, what);
          if (repo)
            {
              Solvable *s;
              FOR_REPO_SOLVABLES(repo, p, s)
                {
                  solv->favormap[p] = idx;
                  if (idx < 0)
                    solv->havedisfavored = 1;
                }
            }
        }
      FOR_JOB_SELECT(p, pp, select, what)
        {
          solv->favormap[p] = idx;
          if (idx < 0)
            solv->havedisfavored = 1;
        }
    }
}

/*
 *
 * solve job queue
 *
 */

int
solver_solve(Solver *solv, Queue *job)
{
  Pool *pool = solv->pool;
  Repo *installed = solv->installed;
  int i;
  int oldnrules, initialnrules;
  Map addedmap;                /* '1' == have pkg-rules for solvable */
  Map installcandidatemap;
  Id how, what, select, name, weak, p, pp, d;
  Queue q;
  Solvable *s, *name_s;
  Rule *r;
  int now, solve_start;
  int needduprules = 0;
  int hasbestinstalljob = 0;
  int hasfavorjob = 0;
  int haslockjob = 0;

  solve_start = solv_timems(0);

  /* log solver options */
  POOL_DEBUG(SOLV_DEBUG_STATS, "solver started\n");
  POOL_DEBUG(SOLV_DEBUG_STATS, "dosplitprovides=%d, noupdateprovide=%d, noinfarchcheck=%d\n", solv->dosplitprovides, solv->noupdateprovide, solv->noinfarchcheck);
  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);
  POOL_DEBUG(SOLV_DEBUG_STATS, "dupallowdowngrade=%d, dupallownamechange=%d, dupallowarchchange=%d, dupallowvendorchange=%d\n", solv->dup_allowdowngrade, solv->dup_allownamechange, solv->dup_allowarchchange, solv->dup_allowvendorchange);
  POOL_DEBUG(SOLV_DEBUG_STATS, "promoteepoch=%d, forbidselfconflicts=%d\n", pool->promoteepoch, pool->forbidselfconflicts);
  POOL_DEBUG(SOLV_DEBUG_STATS, "obsoleteusesprovides=%d, implicitobsoleteusesprovides=%d, obsoleteusescolors=%d, implicitobsoleteusescolors=%d\n", pool->obsoleteusesprovides, pool->implicitobsoleteusesprovides, pool->obsoleteusescolors, pool->implicitobsoleteusescolors);
  POOL_DEBUG(SOLV_DEBUG_STATS, "dontinstallrecommended=%d, addalreadyrecommended=%d onlynamespacerecommended=%d\n", solv->dontinstallrecommended, solv->addalreadyrecommended, solv->only_namespace_recommended);

  /* create whatprovides if not already there */
  if (!pool->whatprovides)
    pool_createwhatprovides(pool);

  /* create obsolete index */
  policy_create_obsolete_index(solv);

  /* remember job */
  queue_free(&solv->job);
  queue_init_clone(&solv->job, job);
  solv->pooljobcnt = pool->pooljobs.count;
  if (pool->pooljobs.count)
    queue_insertn(&solv->job, 0, pool->pooljobs.count, pool->pooljobs.elements);
  job = &solv->job;

  /* free old stuff in case we re-run a solver */
  queuep_free(&solv->update_targets);
  queuep_free(&solv->cleandeps_updatepkgs);
  queue_empty(&solv->ruleassertions);
  solv->bestrules_info = solv_free(solv->bestrules_info);
  solv->yumobsrules_info = solv_free(solv->yumobsrules_info);
  solv->recommendsrules_info = solv_free(solv->recommendsrules_info);
  solv->choicerules_info = solv_free(solv->choicerules_info);
  if (solv->noupdate.size)
    map_empty(&solv->noupdate);
  map_zerosize(&solv->multiversion);
  solv->updatemap_all = 0;
  map_zerosize(&solv->updatemap);
  solv->bestupdatemap_all = 0;
  map_zerosize(&solv->bestupdatemap);
  solv->fixmap_all = 0;
  map_zerosize(&solv->fixmap);
  map_zerosize(&solv->dupmap);
  map_zerosize(&solv->dupinvolvedmap);
  solv->process_orphans = 0;
  solv->droporphanedmap_all = 0;
  map_zerosize(&solv->droporphanedmap);
  solv->allowuninstall_all = 0;
  map_zerosize(&solv->allowuninstallmap);
  map_zerosize(&solv->cleandepsmap);
  map_zerosize(&solv->weakrulemap);
  solv->favormap = solv_free(solv->favormap);
  queue_empty(&solv->weakruleq);
  solv->watches = solv_free(solv->watches);
  queue_empty(&solv->ruletojob);
  if (solv->decisionq.count)
    memset(solv->decisionmap, 0, pool->nsolvables * sizeof(Id));
  queue_empty(&solv->decisionq);
  queue_empty(&solv->decisionq_why);
  queue_empty(&solv->decisionq_reason);
  queue_empty(&solv->learnt_why);
  queue_empty(&solv->learnt_pool);
  queue_empty(&solv->branches);
  solv->propagate_index = 0;
  queue_empty(&solv->problems);
  queue_empty(&solv->solutions);
  queue_empty(&solv->orphaned);
  solv->stats_learned = solv->stats_unsolvable = 0;
  if (solv->recommends_index)
    {
      map_empty(&solv->recommendsmap);
      map_empty(&solv->suggestsmap);
      queuep_free(&solv->recommendscplxq);
      queuep_free(&solv->suggestscplxq);
      solv->recommends_index = 0;
    }
  queuep_free(&solv->brokenorphanrules);
  solv->specialupdaters = solv_free(solv->specialupdaters);


  /*
   * create basic rule set of all involved packages
   * use addedmap bitmap to make sure we don't create rules twice
   */

  /* create multiversion map if needed */
  solver_calculate_multiversionmap(pool, job, &solv->multiversion);

  map_init(&addedmap, pool->nsolvables);
  MAPSET(&addedmap, SYSTEMSOLVABLE);

  map_init(&installcandidatemap, pool->nsolvables);
  queue_init(&q);

  now = solv_timems(0);
  /*
   * create rules for all package that could be involved with the solving
   * so called: pkg rules
   *
   */
  initialnrules = solv->pkgrules_end ? solv->pkgrules_end : 1;
  if (initialnrules > 1)
    deduceq2addedmap(solv, &addedmap);          /* also enables all pkg rules */
  if (solv->nrules != initialnrules)
    solver_shrinkrules(solv, initialnrules);    /* shrink to just pkg rules */
  solv->lastpkgrule = 0;
  solv->pkgrules_end = 0;

  if (installed)
    {
      /* check for update/verify jobs as they need to be known early */
      /* also setup the droporphaned map, we need it when creating update rules */
      for (i = 0; i < job->count; i += 2)
        {
          how = job->elements[i];
          what = job->elements[i + 1];
          select = how & SOLVER_SELECTMASK;
          switch (how & SOLVER_JOBMASK)
            {
            case SOLVER_VERIFY:
              if (select == SOLVER_SOLVABLE_ALL || (select == SOLVER_SOLVABLE_REPO && installed && what == installed->repoid))
                solv->fixmap_all = 1;
              FOR_JOB_SELECT(p, pp, select, what)
                {
                  s = pool->solvables + p;
                  if (s->repo != installed)
                    continue;
                  if (!solv->fixmap.size)
                    map_grow(&solv->fixmap, installed->end - installed->start);
                  MAPSET(&solv->fixmap, p - installed->start);
                }
              break;
            case SOLVER_UPDATE:
              if (select == SOLVER_SOLVABLE_ALL)
                {
                  solv->updatemap_all = 1;
                  if (how & SOLVER_FORCEBEST)
                    solv->bestupdatemap_all = 1;
                  if (how & SOLVER_CLEANDEPS)
                    {
                      FOR_REPO_SOLVABLES(installed, p, s)
                        add_cleandeps_updatepkg(solv, p);
                    }
                }
              else if (select == SOLVER_SOLVABLE_REPO)
                {
                  Repo *repo = pool_id2repo(pool, what);
                  if (!repo)
                    break;
                  if (repo == installed && !(how & SOLVER_TARGETED))
                    {
                      solv->updatemap_all = 1;
                      if (how & SOLVER_FORCEBEST)
                        solv->bestupdatemap_all = 1;
                      if (how & SOLVER_CLEANDEPS)
                        {
                          FOR_REPO_SOLVABLES(installed, p, s)
                            add_cleandeps_updatepkg(solv, p);
                        }
                      break;
                    }
                  if (solv->noautotarget && !(how & SOLVER_TARGETED))
                    break;
                  /* targeted update */
                  FOR_REPO_SOLVABLES(repo, p, s)
                    add_update_target(solv, p, how);
                }
              else
                {
                  if (!(how & SOLVER_TARGETED))
                    {
                      int targeted = 1;
                      FOR_JOB_SELECT(p, pp, select, what)
                        {
                          s = pool->solvables + p;
                          if (s->repo != installed)
                            continue;
                          if (!solv->updatemap.size)
                            map_grow(&solv->updatemap, installed->end - installed->start);
                          MAPSET(&solv->updatemap, p - installed->start);
                          if (how & SOLVER_FORCEBEST)
                            {
                              if (!solv->bestupdatemap.size)
                                map_grow(&solv->bestupdatemap, installed->end - installed->start);
                              MAPSET(&solv->bestupdatemap, p - installed->start);
                            }
                          if (how & SOLVER_CLEANDEPS)
                            add_cleandeps_updatepkg(solv, p);
                          targeted = 0;
                        }
                      if (!targeted || solv->noautotarget)
                        break;
                    }
                  FOR_JOB_SELECT(p, pp, select, what)
                    add_update_target(solv, p, how);
                }
              break;
            case SOLVER_DROP_ORPHANED:
              if (select == SOLVER_SOLVABLE_ALL || (select == SOLVER_SOLVABLE_REPO && installed && what == installed->repoid))
                solv->droporphanedmap_all = 1;
              FOR_JOB_SELECT(p, pp, select, what)
                {
                  s = pool->solvables + p;
                  if (s->repo != installed)
                    continue;
                  if (!solv->droporphanedmap.size)
                    map_grow(&solv->droporphanedmap, installed->end - installed->start);
                  MAPSET(&solv->droporphanedmap, p - installed->start);
                }
              break;
            case SOLVER_ALLOWUNINSTALL:
              if (select == SOLVER_SOLVABLE_ALL || (select == SOLVER_SOLVABLE_REPO && installed && what == installed->repoid))
                solv->allowuninstall_all = 1;
              FOR_JOB_SELECT(p, pp, select, what)
                {
                  s = pool->solvables + p;
                  if (s->repo != installed)
                    continue;
                  if (!solv->allowuninstallmap.size)
                    map_grow(&solv->allowuninstallmap, installed->end - installed->start);
                  MAPSET(&solv->allowuninstallmap, p - installed->start);
                }
              break;
            default:
              break;
            }
        }

      if (solv->update_targets)
        transform_update_targets(solv);

      oldnrules = solv->nrules;
      FOR_REPO_SOLVABLES(installed, p, s)
        solver_addpkgrulesforsolvable(solv, s, &addedmap);
      POOL_DEBUG(SOLV_DEBUG_STATS, "added %d pkg rules for installed solvables\n", solv->nrules - oldnrules);
      oldnrules = solv->nrules;
      FOR_REPO_SOLVABLES(installed, p, s)
        solver_addpkgrulesforupdaters(solv, s, &addedmap, 1);
      POOL_DEBUG(SOLV_DEBUG_STATS, "added %d pkg rules for updaters of installed solvables\n", solv->nrules - oldnrules);
    }

  /*
   * create rules for all packages involved in the job
   * (to be installed or removed)
   */

  oldnrules = solv->nrules;
  for (i = 0; i < job->count; i += 2)
    {
      how = job->elements[i];
      what = job->elements[i + 1];
      select = how & SOLVER_SELECTMASK;

      switch (how & SOLVER_JOBMASK)
        {
        case SOLVER_INSTALL:
          FOR_JOB_SELECT(p, pp, select, what)
            {
              MAPSET(&installcandidatemap, p);
              solver_addpkgrulesforsolvable(solv, pool->solvables + p, &addedmap);
            }
          break;
        case SOLVER_DISTUPGRADE:
          needduprules = 1;
          if (select == SOLVER_SOLVABLE_ALL)
            solv->process_orphans = 1;
          break;
        default:
          break;
        }
    }
  POOL_DEBUG(SOLV_DEBUG_STATS, "added %d pkg rules for packages involved in a job\n", solv->nrules - oldnrules);


  /*
   * add rules for suggests, enhances
   */
  oldnrules = solv->nrules;
  solver_addpkgrulesforweak(solv, &addedmap);
  POOL_DEBUG(SOLV_DEBUG_STATS, "added %d pkg rules because of weak dependencies\n", solv->nrules - oldnrules);

#ifdef ENABLE_LINKED_PKGS
  oldnrules = solv->nrules;
  solver_addpkgrulesforlinked(solv, &addedmap);
  POOL_DEBUG(SOLV_DEBUG_STATS, "added %d pkg rules because of linked packages\n", solv->nrules - oldnrules);
#endif

  /*
   * first pass done, we now have all the pkg rules we need.
   * unify existing rules before going over all job rules and
   * policy rules.
   * at this point the system is always solvable,
   * as an empty system (remove all packages) is a valid solution
   */

  IF_POOLDEBUG (SOLV_DEBUG_STATS)
    {
      int possible = 0, installable = 0;
      for (i = 1; i < pool->nsolvables; i++)
        {
          if (pool_installable(pool, pool->solvables + i))
            installable++;
          if (MAPTST(&addedmap, i))
            possible++;
        }
      POOL_DEBUG(SOLV_DEBUG_STATS, "%d of %d installable solvables considered for solving\n", possible, installable);
    }

  if (solv->nrules > initialnrules)
    solver_unifyrules(solv);                    /* remove duplicate pkg rules */
  solv->pkgrules_end = solv->nrules;            /* mark end of pkg rules */
  solv->lastpkgrule = 0;

  if (solv->nrules > initialnrules)
    addedmap2deduceq(solv, &addedmap);          /* so that we can recreate the addedmap */

  POOL_DEBUG(SOLV_DEBUG_STATS, "pkg rule memory used: %d K\n", solv->nrules * (int)sizeof(Rule) / 1024);
  POOL_DEBUG(SOLV_DEBUG_STATS, "pkg rule creation took %d ms\n", solv_timems(now));

  /* create dup maps if needed. We need the maps early to create our
   * update rules */
  if (needduprules)
    solver_createdupmaps(solv);

  /*
   * create feature rules
   *
   * foreach installed:
   *   create assertion (keep installed, if no update available)
   *   or
   *   create update rule (A|update1(A)|update2(A)|...)
   *
   * those are used later on to keep a version of the installed packages in
   * best effort mode
   */

  solv->featurerules = solv->nrules;              /* mark start of feature rules */
  if (installed)
    {
      /* foreach possibly installed solvable */
      for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
        {
          if (s->repo != installed)
            {
              solver_addrule(solv, 0, 0, 0);    /* create dummy rule */
              continue;
            }
          solver_addfeaturerule(solv, s);
        }
      /* make sure we accounted for all rules */
      assert(solv->nrules - solv->featurerules == installed->end - installed->start);
    }
  solv->featurerules_end = solv->nrules;

    /*
     * Add update rules for installed solvables
     *
     * almost identical to feature rules
     * except that downgrades/archchanges/vendorchanges are not allowed
     */

  solv->updaterules = solv->nrules;

  if (installed)
    { /* foreach installed solvables */
      /* we create all update rules, but disable some later on depending on the job */
      for (i = installed->start, s = pool->solvables + i; i < installed->end; i++, s++)
        {
          Rule *sr;

          if (s->repo != installed)
            {
              solver_addrule(solv, 0, 0, 0);    /* create dummy rule */
              continue;
            }
          solver_addupdaterule(solv, s);
          /*
           * check for and remove duplicate
           */
          r = solv->rules + solv->nrules - 1;           /* r: update rule */
          sr = r - (installed->end - installed->start); /* sr: feature rule */
          if (!r->p)
            {
              if (sr->p)
                memset(sr, 0, sizeof(*sr));             /* no feature rules without update rules */
              continue;
            }
          /* it's also orphaned if the feature rule consists just of the installed package */
          if (!solv->process_orphans && sr->p == i && !sr->d && !sr->w2)
            queue_push(&solv->orphaned, i);

          if (!solver_rulecmp(solv, r, sr))
            memset(sr, 0, sizeof(*sr));         /* delete unneeded feature rule */
          else if (sr->p)
            solver_disablerule(solv, sr);       /* disable feature rule for now */
        }
      /* consistency check: we added a rule for _every_ installed solvable */
      assert(solv->nrules - solv->updaterules == installed->end - installed->start);
    }
  solv->updaterules_end = solv->nrules;


  /*
   * now add all job rules
   */

  solv->jobrules = solv->nrules;
  for (i = 0; i < job->count; i += 2)
    {
      oldnrules = solv->nrules;

      if (i && i == solv->pooljobcnt)
        POOL_DEBUG(SOLV_DEBUG_JOB, "end of pool jobs\n");
      how = job->elements[i];
      what = job->elements[i + 1];
      weak = how & SOLVER_WEAK;
      select = how & SOLVER_SELECTMASK;
      switch (how & SOLVER_JOBMASK)
        {
        case SOLVER_INSTALL:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sinstall %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
          if ((how & SOLVER_CLEANDEPS) != 0 && !solv->cleandepsmap.size && installed)
            map_grow(&solv->cleandepsmap, installed->end - installed->start);
          if (select == SOLVER_SOLVABLE)
            {
              p = what;
              d = 0;
            }
#ifdef ENABLE_COMPLEX_DEPS
          else if ((select == SOLVER_SOLVABLE_PROVIDES || select == SOLVER_SOLVABLE_NAME) && pool_is_complex_dep(pool, what))
            {
              if (add_complex_jobrules(solv, what, select == SOLVER_SOLVABLE_NAME ? CPLXDEPS_NAME : 0, i, weak))
                if (how & SOLVER_FORCEBEST)
                  hasbestinstalljob = 1;
              break;
            }
#endif
          else
            {
              queue_empty(&q);
              FOR_JOB_SELECT(p, pp, select, what)
                queue_push(&q, p);
              if (!q.count)
                {
                  if (select == SOLVER_SOLVABLE_ONE_OF)
                    break;      /* ignore empty installs */
                  /* no candidate found or unsupported, make this an impossible rule */
                  queue_push(&q, -SYSTEMSOLVABLE);
                }
              p = queue_shift(&q);      /* get first candidate */
              d = !q.count ? 0 : pool_queuetowhatprovides(pool, &q);    /* internalize */
            }
          /* force install of namespace supplements hack */
          if (select == SOLVER_SOLVABLE_PROVIDES && !d && (p == SYSTEMSOLVABLE || p == -SYSTEMSOLVABLE) && ISRELDEP(what))
            {
              Reldep *rd = GETRELDEP(pool, what);
              if (rd->flags == REL_NAMESPACE)
                {
                  p = SYSTEMSOLVABLE;
                  if (!solv->installsuppdepq)
                    {
                      solv->installsuppdepq = solv_calloc(1, sizeof(Queue));
                      queue_init(solv->installsuppdepq);
                    }
                  queue_pushunique(solv->installsuppdepq, rd->evr == 0 ? rd->name : what);
                }
            }
          solver_addjobrule(solv, p, 0, d, i, weak);
          if (how & SOLVER_FORCEBEST)
            hasbestinstalljob = 1;
          break;
        case SOLVER_ERASE:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %s%serase %s\n", weak ? "weak " : "", how & SOLVER_CLEANDEPS ? "clean deps " : "", solver_select2str(pool, select, what));
          if ((how & SOLVER_CLEANDEPS) != 0 && !solv->cleandepsmap.size && installed)
            map_grow(&solv->cleandepsmap, installed->end - installed->start);
          /* specific solvable: by id or by nevra */
          name = (select == SOLVER_SOLVABLE || (select == SOLVER_SOLVABLE_NAME && ISRELDEP(what))) ? 0 : -1;
          name_s = 0;
          if (select == SOLVER_SOLVABLE_ALL)    /* hmmm ;) */
            {
              FOR_POOL_SOLVABLES(p)
                solver_addjobrule(solv, -p, 0, 0, i, weak);
            }
          else if (select == SOLVER_SOLVABLE_REPO)
            {
              Repo *repo = pool_id2repo(pool, what);
              if (repo)
                {
                  FOR_REPO_SOLVABLES(repo, p, s)
                    solver_addjobrule(solv, -p, 0, 0, i, weak);
                }
            }
#ifdef ENABLE_COMPLEX_DEPS
          else if ((select == SOLVER_SOLVABLE_PROVIDES || select == SOLVER_SOLVABLE_NAME) && pool_is_complex_dep(pool, what))
            {
              /* no special "erase a specific solvable" handling? */
              add_complex_jobrules(solv, what, select == SOLVER_SOLVABLE_NAME ? (CPLXDEPS_NAME | CPLXDEPS_TODNF | CPLXDEPS_INVERT) : (CPLXDEPS_TODNF | CPLXDEPS_INVERT), i, weak);
              break;
            }
#endif
          FOR_JOB_SELECT(p, pp, select, what)
            {
              s = pool->solvables + p;
              if (installed && s->repo == installed)
                {
                  name = !name ? s->name : -1;
                  name_s = s;
                }
              solver_addjobrule(solv, -p, 0, 0, i, weak);
            }
          /* special case for "erase a specific solvable": we also
           * erase all other solvables with that name, so that they
           * don't get picked up as replacement.
           * name is > 0 if exactly one installed solvable matched.
           */
          /* XXX: look also at packages that obsolete this package? */
          if (name > 0)
            {
              int j, k;
              k = solv->nrules;
              FOR_PROVIDES(p, pp, name)
                {
                  s = pool->solvables + p;
                  if (s->name != name)
                    continue;
                  /* keep other versions installed */
                  if (s->repo == installed)
                    continue;
                  /* keep installcandidates of other jobs */
                  if (MAPTST(&installcandidatemap, p))
                    continue;
                  if (pool->implicitobsoleteusescolors && !pool_colormatch(pool, name_s, s))
                    continue;
                  /* don't add the same rule twice */
                  for (j = oldnrules; j < k; j++)
                    if (solv->rules[j].p == -p)
                      break;
                  if (j == k)
                    solver_addjobrule(solv, -p, 0, 0, i, weak); /* remove by id */
                }
            }
          break;

        case SOLVER_UPDATE:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %supdate %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
          break;
        case SOLVER_VERIFY:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sverify %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
          break;
        case SOLVER_WEAKENDEPS:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %sweaken deps %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
          if (select != SOLVER_SOLVABLE)
            break;
          s = pool->solvables + what;
          weaken_solvable_deps(solv, what);
          break;
        case SOLVER_MULTIVERSION:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %smultiversion %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
          break;
        case SOLVER_LOCK:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %slock %s\n", weak ? "weak " : "", solver_select2str(pool, select, what));
          if (select == SOLVER_SOLVABLE_ALL)
            {
              FOR_POOL_SOLVABLES(p)
                solver_addjobrule(solv, installed && pool->solvables[p].repo == installed ? p : -p, 0, 0, i, weak);
            }
          else if (select == SOLVER_SOLVABLE_REPO)
            {
              Repo *repo = pool_id2repo(pool, what);
              if (repo)
                {
                  FOR_REPO_SOLVABLES(repo, p, s)
                    solver_addjobrule(solv, installed && pool->solvables[p].repo == installed ? p : -p, 0, 0, i, weak);
                }
            }
          FOR_JOB_SELECT(p, pp, select, what)
            solver_addjobrule(solv, installed && pool->solvables[p].repo == installed ? p : -p, 0, 0, i, weak);
          if (solv->nrules != oldnrules)
            haslockjob = 1;
          break;
        case SOLVER_DISTUPGRADE:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: distupgrade %s\n", solver_select2str(pool, select, what));
          break;
        case SOLVER_DROP_ORPHANED:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: drop orphaned %s\n", solver_select2str(pool, select, what));
          break;
        case SOLVER_USERINSTALLED:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: user installed %s\n", solver_select2str(pool, select, what));
          break;
        case SOLVER_ALLOWUNINSTALL:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: allowuninstall %s\n", solver_select2str(pool, select, what));
          break;
        case SOLVER_FAVOR:
        case SOLVER_DISFAVOR:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: %s %s\n", (how & SOLVER_JOBMASK) == SOLVER_FAVOR ? "favor" : "disfavor", solver_select2str(pool, select, what));
          hasfavorjob = 1;
          break;
        default:
          POOL_DEBUG(SOLV_DEBUG_JOB, "job: unknown job\n");
          break;
        }
        
      IF_POOLDEBUG (SOLV_DEBUG_JOB)
        {
          int j;
          if (solv->nrules == oldnrules)
            POOL_DEBUG(SOLV_DEBUG_JOB, "  - no rule created\n");
          for (j = oldnrules; j < solv->nrules; j++)
            {
              POOL_DEBUG(SOLV_DEBUG_JOB, "  - job ");
              solver_printrule(solv, SOLV_DEBUG_JOB, solv->rules + j);
            }
        }
    }
  assert(solv->ruletojob.count == solv->nrules - solv->jobrules);
  solv->jobrules_end = solv->nrules;

  /* create favormap if we have favor jobs */
  if (hasfavorjob)
    setup_favormap(solv);

  /* now create infarch and dup rules */
  if (!solv->noinfarchcheck)
    solver_addinfarchrules(solv, &addedmap);
  else
    solv->infarchrules = solv->infarchrules_end = solv->nrules;

  if (solv->dupinvolvedmap_all || solv->dupinvolvedmap.size)
    solver_addduprules(solv, &addedmap);
  else
    solv->duprules = solv->duprules_end = solv->nrules;

#ifdef ENABLE_LINKED_PKGS
  if (solv->instbuddy && solv->updatemap.size)
    extend_updatemap_to_buddies(solv);
#endif

  if (solv->bestupdatemap_all || solv->bestupdatemap.size || hasbestinstalljob)
    solver_addbestrules(solv, hasbestinstalljob, haslockjob);
  else
    solv->bestrules = solv->bestrules_end = solv->bestrules_up = solv->nrules;

  if (needduprules)
    solver_freedupmaps(solv);   /* no longer needed */

  if (solv->do_yum_obsoletes)
    solver_addyumobsrules(solv);
  else
    solv->yumobsrules = solv->yumobsrules_end = solv->nrules;

  if (solv->havedisfavored && solv->strongrecommends && solv->recommendsruleq)
    solver_addrecommendsrules(solv);
  else
    solv->recommendsrules = solv->recommendsrules_end = solv->nrules;

  if (1)
    solver_addchoicerules(solv);
  else
    solv->choicerules = solv->choicerules_end = solv->nrules;

  /* all rules created
   * --------------------------------------------------------------
   * prepare for solving
   */

  /* free unneeded memory */
  map_free(&addedmap);
  map_free(&installcandidatemap);
  queue_free(&q);

  POOL_DEBUG(SOLV_DEBUG_STATS, "%d pkg rules, 2 * %d update rules, %d job rules, %d infarch rules, %d dup rules, %d choice rules, %d best rules, %d yumobs rules\n", solv->pkgrules_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, solv->bestrules_end - solv->bestrules, solv->yumobsrules_end - solv->yumobsrules);
  POOL_DEBUG(SOLV_DEBUG_STATS, "overall rule memory used: %d K\n", solv->nrules * (int)sizeof(Rule) / 1024);

  /* create weak map */
  if (solv->weakruleq.count || solv->recommendsruleq)
    {
      map_grow(&solv->weakrulemap, solv->nrules);
      for (i = 0; i < solv->weakruleq.count; i++)
        {
          p = solv->weakruleq.elements[i];
          MAPSET(&solv->weakrulemap, p);
        }
      if (solv->recommendsruleq)
        {
          for (i = 0; i < solv->recommendsruleq->count; i++)
            {
              p = solv->recommendsruleq->elements[i];
              MAPSET(&solv->weakrulemap, p);
            }
        }
    }

  /* enable cleandepsmap creation if we have updatepkgs */
  if (solv->cleandeps_updatepkgs && !solv->cleandepsmap.size)
    map_grow(&solv->cleandepsmap, installed->end - installed->start);
  /* no mistakes */
  if (solv->cleandeps_mistakes)
    {
      queue_free(solv->cleandeps_mistakes);
      solv->cleandeps_mistakes = solv_free(solv->cleandeps_mistakes);
    }

  /* all new rules are learnt after this point */
  solv->learntrules = solv->nrules;

  /* create watches chains */
  makewatches(solv);

  /* create assertion index. it is only used to speed up
   * makeruledecsions() a bit */
  for (i = 1, r = solv->rules + i; i < solv->nrules; i++, r++)
    if (r->p && !r->w2 && (r->d == 0 || r->d == -1))
      queue_push(&solv->ruleassertions, i);

  /* disable update rules that conflict with our job */
  solver_disablepolicyrules(solv);

  /* break orphans if requested */
  if (solv->process_orphans && solv->orphaned.count && solv->break_orphans)
    solver_breakorphans(solv);

  /*
   * ********************************************
   * solve!
   * ********************************************
   */

  now = solv_timems(0);
  solver_run_sat(solv, 1, solv->dontinstallrecommended ? 0 : 1);
  POOL_DEBUG(SOLV_DEBUG_STATS, "solver took %d ms\n", solv_timems(now));

  /*
   * prepare solution queue if there were problems
   */
  solver_prepare_solutions(solv);

  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);
  POOL_DEBUG(SOLV_DEBUG_STATS, "solver_solve took %d ms\n", solv_timems(solve_start));

  /* return number of problems */
  return solv->problems.count ? solv->problems.count / 2 : 0;
}

Transaction *
solver_create_transaction(Solver *solv)
{
  return transaction_create_decisionq(solv->pool, &solv->decisionq, &solv->multiversion);
}

void solver_get_orphaned(Solver *solv, Queue *orphanedq)
{
  queue_free(orphanedq);
  queue_init_clone(orphanedq, &solv->orphaned);
}

void solver_get_cleandeps(Solver *solv, Queue *cleandepsq)
{
  Pool *pool = solv->pool;
  Repo *installed = solv->installed;
  Solvable *s;
  Rule *r;
  Id p, pp, pr;

  queue_empty(cleandepsq);
  if (!installed || !solv->cleandepsmap.size)
    return;
  FOR_REPO_SOLVABLES(installed, p, s)
    {
      if (!MAPTST(&solv->cleandepsmap, p - installed->start) || solv->decisionmap[p] >= 0)
        continue;
      /* now check the update rule */
      r = solv->rules + solv->updaterules + (p - solv->installed->start);
      if (r->p)
        {
          FOR_RULELITERALS(pr, pp, r)
            if (solv->decisionmap[pr] > 0)
              break;
          if (pr)
            continue;
        }
      queue_push(cleandepsq, p);
    }
}

void solver_get_recommendations(Solver *solv, Queue *recommendationsq, Queue *suggestionsq, int noselected)
{
  Pool *pool = solv->pool;
  Queue redoq, disabledq;
  int goterase, i;
  Solvable *s;
  Rule *r;
  Map obsmap;

  if (!recommendationsq && !suggestionsq)
    return;

  map_init(&obsmap, pool->nsolvables);
  if (solv->installed)
    {
      Id obs, *obsp, p, po, ppo;
      for (p = solv->installed->start; p < solv->installed->end; p++)
        {
          s = pool->solvables + p;
          if (s->repo != solv->installed || !s->obsoletes)
            continue;
          if (solv->decisionmap[p] <= 0)
            continue;
          if (solv->multiversion.size && MAPTST(&solv->multiversion, p))
            continue;
          obsp = s->repo->idarraydata + s->obsoletes;
          /* foreach obsoletes */
          while ((obs = *obsp++) != 0)
            FOR_PROVIDES(po, ppo, obs)
              MAPSET(&obsmap, po);
        }
    }

  queue_init(&redoq);
  queue_init(&disabledq);
  goterase = 0;
  /* disable all erase jobs (including weak "keep uninstalled" rules) */
  for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
    {
      if (r->d < 0)     /* disabled ? */
        continue;
      if (r->p >= 0)    /* install job? */
        continue;
      queue_push(&disabledq, i);
      solver_disablerule(solv, r);
      goterase++;
    }

  if (goterase)
    {
      enabledisablelearntrules(solv);
      removedisabledconflicts(solv, &redoq);
    }

  /*
   * find recommended packages
   */
  if (recommendationsq)
    {
      Id rec, *recp, p, pp;

      queue_empty(recommendationsq);
      /* create map of all recommened packages */
      solv->recommends_index = -1;
      MAPZERO(&solv->recommendsmap);

      /* put all packages the solver already chose in the map */
      for (i = 1; i < solv->decisionq.count; i++)
        if ((p = solv->decisionq.elements[i]) > 0 && solv->decisionq_why.elements[i] == 0)
          {
            if (solv->decisionq_reason.elements[solv->decisionmap[p]] == SOLVER_REASON_WEAKDEP)
              MAPSET(&solv->recommendsmap, p);
          }

      for (i = 0; i < solv->decisionq.count; i++)
        {
          p = solv->decisionq.elements[i];
          if (p < 0)
            continue;
          s = pool->solvables + p;
          if (s->recommends)
            {
              recp = s->repo->idarraydata + s->recommends;
              while ((rec = *recp++) != 0)
                {
#ifdef ENABLE_COMPLEX_DEPS
                  if (pool_is_complex_dep(pool, rec))
                    {
                      do_complex_recommendations(solv, rec, &solv->recommendsmap, noselected);
                      continue;
                    }
#endif
                  FOR_PROVIDES(p, pp, rec)
                    if (solv->decisionmap[p] > 0)
                      break;
                  if (p)
                    {
                      if (!noselected)
                        {
                          FOR_PROVIDES(p, pp, rec)
                            if (solv->decisionmap[p] > 0)
                              MAPSET(&solv->recommendsmap, p);
                        }
                      continue; /* p != 0: already fulfilled */
                    }
                  FOR_PROVIDES(p, pp, rec)
                    MAPSET(&solv->recommendsmap, p);
                }
            }
        }
      for (i = 1; i < pool->nsolvables; i++)
        {
          if (solv->decisionmap[i] < 0)
            continue;
          if (solv->decisionmap[i] > 0 && noselected)
            continue;
          if (MAPTST(&obsmap, i))
            continue;
          s = pool->solvables + i;
          if (!MAPTST(&solv->recommendsmap, i))
            {
              if (!s->supplements)
                continue;
              if (!pool_installable(pool, s))
                continue;
              if (!solver_is_supplementing(solv, s))
                continue;
            }
          queue_push(recommendationsq, i);
        }
      /* we use MODE_SUGGEST here so that repo prio is ignored */
      policy_filter_unwanted(solv, recommendationsq, POLICY_MODE_SUGGEST);
    }

  /*
   * find suggested packages
   */

  if (suggestionsq)
    {
      Id sug, *sugp, p, pp;

      queue_empty(suggestionsq);
      /* create map of all suggests that are still open */
      solv->recommends_index = -1;
      MAPZERO(&solv->suggestsmap);
      for (i = 0; i < solv->decisionq.count; i++)
        {
          p = solv->decisionq.elements[i];
          if (p < 0)
            continue;
          s = pool->solvables + p;
          if (s->suggests)
            {
              sugp = s->repo->idarraydata + s->suggests;
              while ((sug = *sugp++) != 0)
                {
#ifdef ENABLE_COMPLEX_DEPS
                  if (pool_is_complex_dep(pool, sug))
                    {
                      do_complex_recommendations(solv, sug, &solv->suggestsmap, noselected);
                      continue;
                    }
#endif
                  FOR_PROVIDES(p, pp, sug)
                    if (solv->decisionmap[p] > 0)
                      break;
                  if (p)
                    {
                      if (!noselected)
                        {
                          FOR_PROVIDES(p, pp, sug)
                            if (solv->decisionmap[p] > 0)
                              MAPSET(&solv->suggestsmap, p);
                        }
                      continue; /* already fulfilled */
                    }
                  FOR_PROVIDES(p, pp, sug)
                    MAPSET(&solv->suggestsmap, p);
                }
            }
        }
      for (i = 1; i < pool->nsolvables; i++)
        {
          if (solv->decisionmap[i] < 0)
            continue;
          if (solv->decisionmap[i] > 0 && noselected)
            continue;
          if (MAPTST(&obsmap, i))
            continue;
          s = pool->solvables + i;
          if (!MAPTST(&solv->suggestsmap, i))
            {
              if (!s->enhances)
                continue;
              if (!pool_installable(pool, s))
                continue;
              if (!solver_is_enhancing(solv, s))
                continue;
            }
          queue_push(suggestionsq, i);
        }
      policy_filter_unwanted(solv, suggestionsq, POLICY_MODE_SUGGEST);
    }

  /* undo removedisabledconflicts */
  if (redoq.count)
    undo_removedisabledconflicts(solv, &redoq);
  queue_free(&redoq);

  /* undo job rule disabling */
  for (i = 0; i < disabledq.count; i++)
    solver_enablerule(solv, solv->rules + disabledq.elements[i]);
  queue_free(&disabledq);
  map_free(&obsmap);
}


/***********************************************************************/
/* disk usage computations */

/*-------------------------------------------------------------------
 *
 * calculate DU changes
 */

void
solver_calc_duchanges(Solver *solv, DUChanges *mps, int nmps)
{
  Map installedmap;

  solver_create_state_maps(solv, &installedmap, 0);
  pool_calc_duchanges(solv->pool, &installedmap, mps, nmps);
  map_free(&installedmap);
}


/*-------------------------------------------------------------------
 *
 * calculate changes in install size
 */

int
solver_calc_installsizechange(Solver *solv)
{
  Map installedmap;
  int change;

  solver_create_state_maps(solv, &installedmap, 0);
  change = pool_calc_installsizechange(solv->pool, &installedmap);
  map_free(&installedmap);
  return change;
}

void
solver_create_state_maps(Solver *solv, Map *installedmap, Map *conflictsmap)
{
  pool_create_state_maps(solv->pool, &solv->decisionq, installedmap, conflictsmap);
}

/*-------------------------------------------------------------------
 *
 * decision introspection
 */

int
solver_get_decisionlevel(Solver *solv, Id p)
{
  return solv->decisionmap[p];
}

void
solver_get_decisionqueue(Solver *solv, Queue *decisionq)
{
  queue_free(decisionq);
  queue_init_clone(decisionq, &solv->decisionq);
}

int
solver_get_lastdecisionblocklevel(Solver *solv)
{
  Id p;
  if (solv->decisionq.count == 0)
    return 0;
  p = solv->decisionq.elements[solv->decisionq.count - 1];
  if (p < 0)
    p = -p;
  return solv->decisionmap[p] < 0 ? -solv->decisionmap[p] : solv->decisionmap[p];
}

void
solver_get_decisionblock(Solver *solv, int level, Queue *decisionq)
{
  Id p;
  int i;

  queue_empty(decisionq);
  for (i = 0; i < solv->decisionq.count; i++)
    {
      p = solv->decisionq.elements[i];
      if (p < 0)
        p = -p;
      if (solv->decisionmap[p] == level || solv->decisionmap[p] == -level)
        break;
    }
  if (i == solv->decisionq.count)
    return;
  for (i = 0; i < solv->decisionq.count; i++)
    {
      p = solv->decisionq.elements[i];
      if (p < 0)
        p = -p;
      if (solv->decisionmap[p] == level || solv->decisionmap[p] == -level)
        queue_push(decisionq, p);
      else
        break;
    }
}

int
solver_describe_decision(Solver *solv, Id p, Id *infop)
{
  int i;
  Id pp, why;

  if (infop)
    *infop = 0;
  if (!solv->decisionmap[p])
    return SOLVER_REASON_UNRELATED;
  pp = solv->decisionmap[p] < 0 ? -p : p;
  for (i = 0; i < solv->decisionq.count; i++)
    if (solv->decisionq.elements[i] == pp)
      break;
  if (i == solv->decisionq.count)       /* just in case... */
    return SOLVER_REASON_UNRELATED;
  why = solv->decisionq_why.elements[i];
  if (infop)
    *infop = why > 0 ? why : -why;
  if (why > 0)
    return SOLVER_REASON_UNIT_RULE;
  i = solv->decisionmap[p] >= 0 ? solv->decisionmap[p] : -solv->decisionmap[p];
  return solv->decisionq_reason.elements[i];
}


void
solver_describe_weakdep_decision(Solver *solv, Id p, Queue *whyq)
{
  Pool *pool = solv->pool;
  int i;
  int level = solv->decisionmap[p];
  int decisionno;
  Solvable *s;

  queue_empty(whyq);
  if (level < 0)
    return;     /* huh? */
  for (decisionno = 0; decisionno < solv->decisionq.count; decisionno++)
    if (solv->decisionq.elements[decisionno] == p)
      break;
  if (decisionno == solv->decisionq.count)
    return;     /* huh? */
  i = solv->decisionmap[p] >= 0 ? solv->decisionmap[p] : -solv->decisionmap[p];
  if (solv->decisionq_reason.elements[i] != SOLVER_REASON_WEAKDEP)
    return;     /* huh? */

  /* 1) list all packages that recommend us */
  for (i = 1; i < pool->nsolvables; i++)
    {
      Id *recp, rec, pp2, p2;
      if (solv->decisionmap[i] <= 0 || solv->decisionmap[i] >= level)
        continue;
      s = pool->solvables + i;
      if (!s->recommends)
        continue;
      if (!solv->addalreadyrecommended && s->repo == solv->installed)
        continue;
      recp = s->repo->idarraydata + s->recommends;
      while ((rec = *recp++) != 0)
        {
          int found = 0;
          FOR_PROVIDES(p2, pp2, rec)
            {
              if (p2 == p)
                found = 1;
              else
                {
                  /* if p2 is already installed, this recommends is ignored */
                  if (solv->decisionmap[p2] > 0 && solv->decisionmap[p2] < level)
                    break;
                }
            }
          if (!p2 && found)
            {
              queue_push(whyq, SOLVER_REASON_RECOMMENDED);
              queue_push2(whyq, i, rec);
            }
        }
    }
  /* 2) list all supplements */
  s = pool->solvables + p;
  if (s->supplements && level > 0)
    {
      Id *supp, sup, pp2, p2;
      /* this is a hack. to use solver_dep_fulfilled we temporarily clear
       * everything above our level in the decisionmap */
      for (i = decisionno; i < solv->decisionq.count; i++ )
        {
          p2 = solv->decisionq.elements[i];
          if (p2 > 0)
            solv->decisionmap[p2] = -solv->decisionmap[p2];
        }
      supp = s->repo->idarraydata + s->supplements;
      while ((sup = *supp++) != 0)
        if (solver_dep_fulfilled(solv, sup))
          {
            int found = 0;
            /* let's see if this is an easy supp */
            FOR_PROVIDES(p2, pp2, sup)
              {
                if (!solv->addalreadyrecommended && solv->installed)
                  {
                    if (pool->solvables[p2].repo == solv->installed)
                      continue;
                  }
                if (solv->decisionmap[p2] > 0 && solv->decisionmap[p2] < level)
                  {
                    queue_push(whyq, SOLVER_REASON_SUPPLEMENTED);
                    queue_push2(whyq, p2, sup);
                    found = 1;
                  }
              }
            if (!found)
              {
                /* hard case, just note dependency with no package */
                queue_push(whyq, SOLVER_REASON_SUPPLEMENTED);
                queue_push2(whyq, 0, sup);
              }
          }
      for (i = decisionno; i < solv->decisionq.count; i++)
        {
          p2 = solv->decisionq.elements[i];
          if (p2 > 0)
            solv->decisionmap[p2] = -solv->decisionmap[p2];
        }
    }
}

void
pool_job2solvables(Pool *pool, Queue *pkgs, Id how, Id what)
{
  Id p, pp;
  how &= SOLVER_SELECTMASK;
  queue_empty(pkgs);
  if (how == SOLVER_SOLVABLE_ALL)
    {
      FOR_POOL_SOLVABLES(p)
        queue_push(pkgs, p);
    }
  else if (how == SOLVER_SOLVABLE_REPO)
    {
      Repo *repo = pool_id2repo(pool, what);
      Solvable *s;
      if (repo)
        {
          FOR_REPO_SOLVABLES(repo, p, s)
            queue_push(pkgs, p);
        }
    }
  else
    {
      FOR_JOB_SELECT(p, pp, how, what)
        queue_push(pkgs, p);
    }
}

int
pool_isemptyupdatejob(Pool *pool, Id how, Id what)
{
  Id p, pp, pi, pip;
  Id select = how & SOLVER_SELECTMASK;
  if ((how & SOLVER_JOBMASK) != SOLVER_UPDATE)
    return 0;
  if (select == SOLVER_SOLVABLE_ALL || select == SOLVER_SOLVABLE_REPO)
    return 0;
  if (!pool->installed)
    return 1;
  FOR_JOB_SELECT(p, pp, select, what)
    if (pool->solvables[p].repo == pool->installed)
      return 0;
  /* hard work */
  FOR_JOB_SELECT(p, pp, select, what)
    {
      Solvable *s = pool->solvables + p;
      FOR_PROVIDES(pi, pip, s->name)
        {
          Solvable *si = pool->solvables + pi;
          if (si->repo != pool->installed || si->name != s->name)
            continue;
          return 0;
        }
      if (s->obsoletes)
        {
          Id obs, *obsp = s->repo->idarraydata + s->obsoletes;
          while ((obs = *obsp++) != 0)
            {
              FOR_PROVIDES(pi, pip, obs)
                {
                  Solvable *si = pool->solvables + pi;
                  if (si->repo != pool->installed)
                    continue;
                  if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, si, obs))
                    continue;
                  if (pool->obsoleteusescolors && !pool_colormatch(pool, s, si))
                    continue;
                  return 0;
                }
            }
        }
    }
  return 1;
}

int
solver_alternatives_count(Solver *solv)
{
  Id *elements = solv->branches.elements;
  int res, count;
  for (res = 0, count = solv->branches.count; count; res++)
    count -= elements[count - 2];
  return res;
}

int
solver_get_alternative(Solver *solv, Id alternative, Id *idp, Id *fromp, Id *chosenp, Queue *choices, int *levelp)
{
  int cnt = solver_alternatives_count(solv);
  int count = solv->branches.count;
  Id *elements = solv->branches.elements;
  if (choices)
    queue_empty(choices);
  if (alternative <= 0 || alternative > cnt)
    return 0;
  elements += count;
  for (; cnt > alternative; cnt--)
    elements -= elements[-2];
  if (levelp)
    *levelp = elements[-1];
  if (fromp)
    *fromp = elements[-4];
  if (idp)
    *idp = elements[-3];
  if (chosenp)
    {
      int i;
      *chosenp = 0;
      for (i = elements[-2]; i > 4; i--)
        {
          Id p = -elements[-i];
          if (p > 0 && solv->decisionmap[p] == elements[-1] + 1)
            {
              *chosenp = p;
              break;
            }
        }
    }
  if (choices)
    queue_insertn(choices, 0, elements[-2] - 4, elements - elements[-2]);
  return elements[-4] ? SOLVER_ALTERNATIVE_TYPE_RECOMMENDS : SOLVER_ALTERNATIVE_TYPE_RULE;
}

const char *
solver_select2str(Pool *pool, Id select, Id what)
{
  const char *s;
  char *b;
  select &= SOLVER_SELECTMASK;
  if (select == SOLVER_SOLVABLE)
    return pool_solvid2str(pool, what);
  if (select == SOLVER_SOLVABLE_NAME)
    return pool_dep2str(pool, what);
  if (select == SOLVER_SOLVABLE_PROVIDES)
    {
      s = pool_dep2str(pool, what);
      b = pool_alloctmpspace(pool, 11 + strlen(s));
      sprintf(b, "providing %s", s);
      return b;
    }
  if (select == SOLVER_SOLVABLE_ONE_OF)
    {
      Id p;
      b = 0;
      while ((p = pool->whatprovidesdata[what++]) != 0)
        {
          s = pool_solvid2str(pool, p);
          if (b)
            b = pool_tmpappend(pool, b, ", ", s);
          else
            b = pool_tmpjoin(pool, s, 0, 0);
          pool_freetmpspace(pool, s);
        }
      return b ? b : "nothing";
    }
  if (select == SOLVER_SOLVABLE_REPO)
    {
      b = pool_alloctmpspace(pool, 20);
      sprintf(b, "repo #%d", what);
      return b;
    }
  if (select == SOLVER_SOLVABLE_ALL)
    return "all packages";
  return "unknown job select";
}

const char *
pool_job2str(Pool *pool, Id how, Id what, Id flagmask)
{
  Id select = how & SOLVER_SELECTMASK;
  const char *strstart = 0, *strend = 0;
  char *s;
  int o;

  switch (how & SOLVER_JOBMASK)
    {
    case SOLVER_NOOP:
      return "do nothing";
    case SOLVER_INSTALL:
      if (select == SOLVER_SOLVABLE && pool->installed && pool->solvables[what].repo == pool->installed)
        strstart = "keep ", strend = " installed";
      else if (select == SOLVER_SOLVABLE || select == SOLVER_SOLVABLE_NAME)
        strstart = "install ";
      else if (select == SOLVER_SOLVABLE_PROVIDES)
        strstart = "install a package ";
      else
        strstart = "install one of ";
      break;
    case SOLVER_ERASE:
      if (select == SOLVER_SOLVABLE && !(pool->installed && pool->solvables[what].repo == pool->installed))
        strstart = "keep ", strend = " uninstalled";
      else if (select == SOLVER_SOLVABLE_PROVIDES)
        strstart = "deinstall all packages ";
      else
        strstart = "deinstall ";
      break;
    case SOLVER_UPDATE:
      strstart = "update ";
      break;
    case SOLVER_WEAKENDEPS:
      strstart = "weaken deps of ";
      break;
    case SOLVER_MULTIVERSION:
      strstart = "multi version ";
      break;
    case SOLVER_LOCK:
      strstart = "lock ";
      break;
    case SOLVER_DISTUPGRADE:
      strstart = "dist upgrade ";
      break;
    case SOLVER_VERIFY:
      strstart = "verify ";
      break;
    case SOLVER_DROP_ORPHANED:
      strstart = "deinstall ", strend = " if orphaned";
      break;
    case SOLVER_USERINSTALLED:
      strstart = "regard ", strend = " as userinstalled";
      break;
    case SOLVER_ALLOWUNINSTALL:
      strstart = "allow deinstallation of ";
      break;
    case SOLVER_FAVOR:
      strstart = "favor ";
      break;
    case SOLVER_DISFAVOR:
      strstart = "disfavor ";
      break;
    default:
      strstart = "unknown job ";
      break;
    }
  s = pool_tmpjoin(pool, strstart, solver_select2str(pool, select, what), strend);
  how &= flagmask;
  if ((how & ~(SOLVER_SELECTMASK|SOLVER_JOBMASK)) == 0)
    return s;
  o = strlen(s);
  s = pool_tmpappend(pool, s, " ", 0);
  if (how & SOLVER_WEAK)
    s = pool_tmpappend(pool, s, ",weak", 0);
  if (how & SOLVER_ESSENTIAL)
    s = pool_tmpappend(pool, s, ",essential", 0);
  if (how & SOLVER_CLEANDEPS)
    s = pool_tmpappend(pool, s, ",cleandeps", 0);
  if (how & SOLVER_ORUPDATE)
    s = pool_tmpappend(pool, s, ",orupdate", 0);
  if (how & SOLVER_FORCEBEST)
    s = pool_tmpappend(pool, s, ",forcebest", 0);
  if (how & SOLVER_TARGETED)
    s = pool_tmpappend(pool, s, ",targeted", 0);
  if (how & SOLVER_SETEV)
    s = pool_tmpappend(pool, s, ",setev", 0);
  if (how & SOLVER_SETEVR)
    s = pool_tmpappend(pool, s, ",setevr", 0);
  if (how & SOLVER_SETARCH)
    s = pool_tmpappend(pool, s, ",setarch", 0);
  if (how & SOLVER_SETVENDOR)
    s = pool_tmpappend(pool, s, ",setvendor", 0);
  if (how & SOLVER_SETREPO)
    s = pool_tmpappend(pool, s, ",setrepo", 0);
  if (how & SOLVER_SETNAME)
    s = pool_tmpappend(pool, s, ",setname", 0);
  if (how & SOLVER_NOAUTOSET)
    s = pool_tmpappend(pool, s, ",noautoset", 0);
  if (s[o + 1] != ',')
    s = pool_tmpappend(pool, s, ",?", 0);
  s[o + 1] = '[';
  return pool_tmpappend(pool, s, "]", 0);
}

const char *
solver_alternative2str(Solver *solv, int type, Id id, Id from)
{
  Pool *pool = solv->pool;
  if (type == SOLVER_ALTERNATIVE_TYPE_RECOMMENDS)
    {
      const char *s = pool_dep2str(pool, id);
      return pool_tmpappend(pool, s, ", recommended by ", pool_solvid2str(pool, from));
    }
  if (type == SOLVER_ALTERNATIVE_TYPE_RULE)
    {
      int rtype;
      Id depfrom, depto, dep;
      char buf[64];
      if (solver_ruleclass(solv, id) == SOLVER_RULE_CHOICE)
        id = solver_rule2pkgrule(solv, id);
      if (solver_ruleclass(solv, id) == SOLVER_RULE_RECOMMENDS)
        id = solver_rule2pkgrule(solv, id);
      rtype = solver_ruleinfo(solv, id, &depfrom, &depto, &dep);
      if ((rtype & SOLVER_RULE_TYPEMASK) == SOLVER_RULE_JOB)
        {
          if ((depto & SOLVER_SELECTMASK) == SOLVER_SOLVABLE_PROVIDES)
            return pool_dep2str(pool, dep);
          return solver_select2str(pool, depto & SOLVER_SELECTMASK, dep);
        }
      if (rtype == SOLVER_RULE_PKG_REQUIRES)
        {
          const char *s = pool_dep2str(pool, dep);
          return pool_tmpappend(pool, s, ", required by ", pool_solvid2str(pool, depfrom));
        }
      sprintf(buf, "Rule #%d", id);
      return pool_tmpjoin(pool, buf, 0, 0);
    }
  return "unknown alternative type";
}