+/*
+ * prune to repository with highest priority.
+ * does not prune installed solvables.
+ */
+
+static void
+prune_to_highest_prio(Pool *pool, Queue *plist)
+{
+ int i, j;
+ Solvable *s;
+ int bestprio = 0, bestprioset = 0;
+
+ /* prune to highest priority */
+ for (i = 0; i < plist->count; i++) /* find highest prio in queue */
+ {
+ s = pool->solvables + plist->elements[i];
+ if (pool->installed && s->repo == pool->installed)
+ continue;
+ if (!bestprioset || s->repo->priority > bestprio)
+ {
+ bestprio = s->repo->priority;
+ bestprioset = 1;
+ }
+ }
+ if (!bestprioset)
+ return;
+ for (i = j = 0; i < plist->count; i++) /* remove all with lower prio */
+ {
+ s = pool->solvables + plist->elements[i];
+ if (s->repo->priority == bestprio || (pool->installed && s->repo == pool->installed))
+ plist->elements[j++] = plist->elements[i];
+ }
+ plist->count = j;
+}
+
+
+/* installed packages involed in a dup operation can only be kept
+ * if they are identical to a non-installed one */
+static void
+solver_prune_installed_dup_packages(Solver *solv, Queue *plist)
+{
+ Pool *pool = solv->pool;
+ int i, j, bestprio = 0;
+
+ /* find bestprio (again) */
+ for (i = 0; i < plist->count; i++)
+ {
+ Solvable *s = pool->solvables + plist->elements[i];
+ if (s->repo != pool->installed)
+ {
+ bestprio = s->repo->priority;
+ break;
+ }
+ }
+ if (i == plist->count)
+ return; /* only installed packages, could not find prio */
+ for (i = j = 0; i < plist->count; i++)
+ {
+ Id p = plist->elements[i];
+ Solvable *s = pool->solvables + p;
+ if (s->repo != pool->installed && s->repo->priority < bestprio)
+ continue;
+ if (s->repo == pool->installed && (solv->dupmap_all || (solv->dupinvolvedmap.size && MAPTST(&solv->dupinvolvedmap, p))))
+ {
+ Id p2, pp2;
+ int keepit = 0;
+ FOR_PROVIDES(p2, pp2, s->name)
+ {
+ Solvable *s2 = pool->solvables + p2;
+ if (s2->repo == pool->installed || s2->evr != s->evr || s2->repo->priority < bestprio)
+ continue;
+ if (!solvable_identical(s, s2))
+ continue;
+ keepit = 1;
+ if (s2->repo->priority > bestprio)
+ {
+ /* new max prio! */
+ bestprio = s2->repo->priority;
+ j = 0;
+ }
+ }
+ if (!keepit)
+ continue; /* no identical package found, ignore installed package */
+ }
+ plist->elements[j++] = p;
+ }
+ if (j)
+ plist->count = j;
+}
+
+/*
+ * like prune_to_highest_prio, but calls solver prune_installed_dup_packages
+ * when there are dup packages
+ */
+static inline void
+solver_prune_to_highest_prio(Solver *solv, Queue *plist)
+{
+ prune_to_highest_prio(solv->pool, plist);
+ if (plist->count > 1 && solv->pool->installed && (solv->dupmap_all || solv->dupinvolvedmap.size))
+ solver_prune_installed_dup_packages(solv, plist);
+}
+
+
+static void
+solver_prune_to_highest_prio_per_name(Solver *solv, Queue *plist)
+{
+ Pool *pool = solv->pool;
+ Queue pq;
+ int i, j, k;
+ Id name;
+
+ queue_init(&pq);
+ solv_sort(plist->elements, plist->count, sizeof(Id), prune_to_best_version_sortcmp, pool);
+ queue_push(&pq, plist->elements[0]);
+ name = pool->solvables[pq.elements[0]].name;
+ for (i = 1, j = 0; i < plist->count; i++)
+ {
+ if (pool->solvables[plist->elements[i]].name != name)
+ {
+ if (pq.count > 2)
+ solver_prune_to_highest_prio(solv, &pq);
+ for (k = 0; k < pq.count; k++)
+ plist->elements[j++] = pq.elements[k];
+ queue_empty(&pq);
+ queue_push(&pq, plist->elements[i]);
+ name = pool->solvables[pq.elements[0]].name;
+ }
+ }
+ if (pq.count > 2)
+ solver_prune_to_highest_prio(solv, &pq);
+ for (k = 0; k < pq.count; k++)
+ plist->elements[j++] = pq.elements[k];
+ queue_free(&pq);
+ plist->count = j;
+}
+
+
+/*
+ * prune to recommended/suggested packages.
+ * does not prune installed packages (they are also somewhat recommended).
+ */
+
+static void
+prune_to_recommended(Solver *solv, Queue *plist)
+{
+ Pool *pool = solv->pool;
+ int i, j, k, ninst;
+ Solvable *s;
+ Id p, pp, rec, *recp, sug, *sugp;
+
+ ninst = 0;
+ if (pool->installed)
+ {
+ for (i = 0; i < plist->count; i++)
+ {
+ p = plist->elements[i];
+ s = pool->solvables + p;
+ if (pool->installed && s->repo == pool->installed)
+ ninst++;
+ }
+ }
+ if (plist->count - ninst < 2)
+ return;
+
+ /* update our recommendsmap/suggestsmap */
+ if (solv->recommends_index < 0)
+ {
+ MAPZERO(&solv->recommendsmap);
+ MAPZERO(&solv->suggestsmap);
+ solv->recommends_index = 0;
+ }
+ while (solv->recommends_index < solv->decisionq.count)
+ {
+ p = solv->decisionq.elements[solv->recommends_index++];
+ if (p < 0)
+ continue;
+ s = pool->solvables + p;
+ if (s->recommends)
+ {
+ recp = s->repo->idarraydata + s->recommends;
+ while ((rec = *recp++) != 0)
+ FOR_PROVIDES(p, pp, rec)
+ MAPSET(&solv->recommendsmap, p);
+ }
+ if (s->suggests)
+ {
+ sugp = s->repo->idarraydata + s->suggests;
+ while ((sug = *sugp++) != 0)
+ FOR_PROVIDES(p, pp, sug)
+ MAPSET(&solv->suggestsmap, p);
+ }
+ }
+
+ /* prune to recommended/supplemented */
+ ninst = 0;
+ for (i = j = 0; i < plist->count; i++)
+ {
+ p = plist->elements[i];
+ s = pool->solvables + p;
+ if (pool->installed && s->repo == pool->installed)
+ {
+ ninst++;
+ if (j)
+ plist->elements[j++] = p;
+ continue;
+ }
+ if (!MAPTST(&solv->recommendsmap, p))
+ if (!solver_is_supplementing(solv, s))
+ continue;
+ if (!j && ninst)
+ {
+ for (k = 0; j < ninst; k++)
+ {
+ s = pool->solvables + plist->elements[k];
+ if (pool->installed && s->repo == pool->installed)
+ plist->elements[j++] = plist->elements[k];
+ }
+ }
+ plist->elements[j++] = p;
+ }
+ if (j)
+ plist->count = j;
+
+ /* anything left to prune? */
+ if (plist->count - ninst < 2)
+ return;
+
+ /* prune to suggested/enhanced */
+ ninst = 0;
+ for (i = j = 0; i < plist->count; i++)
+ {
+ p = plist->elements[i];
+ s = pool->solvables + p;
+ if (pool->installed && s->repo == pool->installed)
+ {
+ ninst++;
+ if (j)
+ plist->elements[j++] = p;
+ continue;
+ }
+ if (!MAPTST(&solv->suggestsmap, p))
+ if (!solver_is_enhancing(solv, s))
+ continue;
+ if (!j && ninst)
+ {
+ for (k = 0; j < ninst; k++)
+ {
+ s = pool->solvables + plist->elements[k];
+ if (pool->installed && s->repo == pool->installed)
+ plist->elements[j++] = plist->elements[k];
+ }
+ }
+ plist->elements[j++] = p;
+ }
+ if (j)
+ plist->count = j;
+}
+
+static void
+prune_to_best_arch(const Pool *pool, Queue *plist)
+{
+ Id a, bestscore;
+ Solvable *s;
+ int i, j;
+
+ if (!pool->id2arch || plist->count < 2)
+ return;
+ bestscore = 0;
+ for (i = 0; i < plist->count; i++)
+ {
+ s = pool->solvables + plist->elements[i];
+ a = s->arch;
+ a = (a <= pool->lastarch) ? pool->id2arch[a] : 0;
+ if (a && a != 1 && (!bestscore || a < bestscore))
+ bestscore = a;
+ }
+ if (!bestscore)
+ return;
+ for (i = j = 0; i < plist->count; i++)
+ {
+ s = pool->solvables + plist->elements[i];
+ a = s->arch;
+ if (a > pool->lastarch)
+ continue;
+ a = pool->id2arch[a];
+ /* a == 1 -> noarch */
+ if (a != 1 && ((a ^ bestscore) & 0xffff0000) != 0)
+ continue;
+ plist->elements[j++] = plist->elements[i];
+ }
+ if (j)
+ plist->count = j;
+}
+
+
+struct trj_data {
+ Pool *pool;
+ Queue *plist;
+ Id *stack;
+ Id nstack;
+ Id *low;
+ Id firstidx;
+ Id idx;
+};
+
+/* This is Tarjan's SCC algorithm, slightly modified */
+static void
+trj_visit(struct trj_data *trj, Id node)
+{
+ Id *low = trj->low;
+ Pool *pool = trj->pool;
+ Queue *plist = trj->plist;
+ Id myidx, stackstart;
+ Solvable *s;
+ int i;
+ Id p, pp, obs, *obsp;
+
+ low[node] = myidx = trj->idx++;
+ trj->stack[(stackstart = trj->nstack++)] = node;
+
+ s = pool->solvables + plist->elements[node];
+ if (s->obsoletes)
+ {
+ obsp = s->repo->idarraydata + s->obsoletes;
+ while ((obs = *obsp++) != 0)
+ {
+ FOR_PROVIDES(p, pp, obs)
+ {
+ Solvable *ps = pool->solvables + p;
+ if (ps->name == s->name)
+ continue;
+ if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, ps, obs))
+ continue;
+ if (pool->obsoleteusescolors && !pool_colormatch(pool, s, ps))
+ continue;
+ /* hmm, expensive. should use hash if plist is big */
+ for (i = 0; i < plist->count; i++)
+ {
+ if (node != i && plist->elements[i] == p)
+ {
+ Id l = low[i];
+ if (!l)
+ {
+ if (!ps->obsoletes)
+ {
+ /* don't bother */
+ trj->idx++;
+ low[i] = -1;
+ continue;
+ }
+ trj_visit(trj, i);
+ l = low[i];
+ }
+ if (l < 0)
+ continue;
+ if (l < trj->firstidx)
+ {
+ int k;
+ /* this means we have reached an old SCC found earlier.
+ * delete it as we obsolete it */
+ for (k = l; ; k++)
+ {
+ if (low[trj->stack[k]] == l)
+ low[trj->stack[k]] = -1;
+ else
+ break;
+ }
+ }
+ else if (l < low[node])
+ low[node] = l;
+ }
+ }
+ }
+ }
+ }
+ if (low[node] == myidx) /* found a SCC? */
+ {
+ /* we're only interested in SCCs that contain the first node,
+ * as all others are "obsoleted" */
+ if (myidx != trj->firstidx)
+ myidx = -1;
+ for (i = stackstart; i < trj->nstack; i++)
+ low[trj->stack[i]] = myidx;
+ trj->nstack = stackstart; /* empty stack */
+ }
+}
+
+/*
+ * remove entries from plist that are obsoleted by other entries
+ * with different name.
+ */
+static void
+prune_obsoleted(Pool *pool, Queue *plist)
+{
+ Id data_buf[2 * 16], *data;
+ struct trj_data trj;
+ int i, j;
+ Solvable *s;
+
+ if (plist->count <= 16)
+ {
+ memset(data_buf, 0, sizeof(data_buf));
+ data = data_buf;
+ }
+ else
+ data = solv_calloc(plist->count, 2 * sizeof(Id));
+ trj.pool = pool;
+ trj.plist = plist;
+ trj.low = data;
+ trj.idx = 1;
+ trj.stack = data + plist->count - 1; /* -1 so we can index with idx (which starts with 1) */
+ for (i = 0; i < plist->count; i++)
+ {
+ if (trj.low[i])
+ continue;
+ s = pool->solvables + plist->elements[i];
+ if (s->obsoletes)
+ {
+ trj.firstidx = trj.nstack = trj.idx;
+ trj_visit(&trj, i);
+ }
+ else
+ {
+ Id myidx = trj.idx++;
+ trj.low[i] = myidx;
+ trj.stack[myidx] = i;
+ }
+ }
+ for (i = j = 0; i < plist->count; i++)
+ if (trj.low[i] >= 0)
+ plist->elements[j++] = plist->elements[i];
+ plist->count = j;
+ if (data != data_buf)
+ solv_free(data);
+}
+
+/* this is prune_obsoleted special-cased for two elements */
+static void
+prune_obsoleted_2(Pool *pool, Queue *plist)
+{
+ int i;
+ Solvable *s;
+ Id p, pp, obs, *obsp;
+ Id other;
+ int obmap = 0;
+
+ for (i = 0; i < 2; i++)
+ {
+ s = pool->solvables + plist->elements[i];
+ other = plist->elements[1 - i];
+ if (s->obsoletes)
+ {
+ obsp = s->repo->idarraydata + s->obsoletes;
+ while ((obs = *obsp++) != 0)
+ {
+ FOR_PROVIDES(p, pp, obs)
+ {
+ Solvable *ps;
+ if (p != other)
+ continue;
+ ps = pool->solvables + p;
+ if (ps->name == s->name)
+ continue;
+ if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, ps, obs))
+ continue;
+ if (pool->obsoleteusescolors && !pool_colormatch(pool, s, ps))
+ continue;
+ obmap |= 1 << i;
+ break;
+ }
+ if (p)
+ break;
+ }
+ }
+ }
+ if (obmap == 0 || obmap == 3)
+ return;
+ if (obmap == 2)
+ plist->elements[0] = plist->elements[1];
+ plist->count = 1;
+}
+
+/*
+ * bring those elements to the front of the queue that
+ * have a installed solvable with the same name
+ */
+static void
+move_installed_to_front(Pool *pool, Queue *plist)
+{
+ int i, j;
+ Solvable *s;
+ Id p, pp;
+
+ for (i = j = 0; i < plist->count; i++)
+ {
+ s = pool->solvables + plist->elements[i];
+ if (s->repo != pool->installed)
+ {
+ FOR_PROVIDES(p, pp, s->name)
+ {
+ Solvable *ps = pool->solvables + p;
+ if (s->name == ps->name && ps->repo == pool->installed)
+ {
+ s = ps;
+ break;
+ }
+ }
+ }
+ if (s->repo == pool->installed)
+ {
+ if (i != j)
+ {
+ p = plist->elements[i];
+ if (i - j == 1)
+ plist->elements[i] = plist->elements[j];
+ else
+ memmove(plist->elements + j + 1, plist->elements + j, (i - j) * sizeof(Id));
+ plist->elements[j] = p;
+ }
+ else if (j + 2 == plist->count)
+ break; /* no need to check last element if all prev ones are installed */
+ j++;
+ }
+ }
+}
+
+/*
+ * prune_to_best_version
+ *
+ * sort list of packages (given through plist) by name and evr
+ * return result through plist
+ */
+static void
+prune_to_best_version(Pool *pool, Queue *plist)
+{
+ int i, j;
+ Solvable *s, *best;
+
+ if (plist->count < 2) /* no need to prune for a single entry */
+ return;
+ POOL_DEBUG(SOLV_DEBUG_POLICY, "prune_to_best_version %d\n", plist->count);
+
+ /* sort by name first, prefer installed */
+ solv_sort(plist->elements, plist->count, sizeof(Id), prune_to_best_version_sortcmp, pool);
+
+ /* now find best 'per name' */
+ best = 0;
+ for (i = j = 0; i < plist->count; i++)
+ {
+ s = pool->solvables + plist->elements[i];
+
+ POOL_DEBUG(SOLV_DEBUG_POLICY, "- %s[%s]\n",
+ pool_solvable2str(pool, s),
+ (pool->installed && s->repo == pool->installed) ? "installed" : "not installed");
+
+ if (!best) /* if no best yet, the current is best */
+ {
+ best = s;
+ continue;
+ }
+
+ /* name switch: finish group, re-init */
+ if (best->name != s->name) /* new name */
+ {
+ plist->elements[j++] = best - pool->solvables; /* move old best to front */
+ best = s; /* take current as new best */
+ continue;
+ }
+
+ if (best->evr != s->evr) /* compare evr */
+ {
+ if (pool_evrcmp(pool, best->evr, s->evr, EVRCMP_COMPARE) < 0)
+ best = s;
+ }
+ }
+ plist->elements[j++] = best - pool->solvables; /* finish last group */
+ plist->count = j;
+
+ /* we reduced the list to one package per name, now look at
+ * package obsoletes */
+ if (plist->count > 1)
+ {
+ if (plist->count == 2)
+ prune_obsoleted_2(pool, plist);
+ else
+ prune_obsoleted(pool, plist);
+ }
+ if (plist->count > 1 && pool->installed)
+ move_installed_to_front(pool, plist);
+}
+
+
+/*
+ * POLICY_MODE_CHOOSE: default, do all pruning steps
+ * POLICY_MODE_RECOMMEND: leave out prune_to_recommended
+ * POLICY_MODE_SUGGEST: leave out prune_to_recommended, do prio pruning just per name
+ */
+void
+policy_filter_unwanted(Solver *solv, Queue *plist, int mode)
+{
+ Pool *pool = solv->pool;
+ if (plist->count > 1)
+ {
+ if (mode != POLICY_MODE_SUGGEST)
+ solver_prune_to_highest_prio(solv, plist);
+ else
+ solver_prune_to_highest_prio_per_name(solv, plist);
+ }
+ if (plist->count > 1)
+ prune_to_best_arch(pool, plist);
+ if (plist->count > 1)
+ prune_to_best_version(pool, plist);
+ if (plist->count > 1 && mode == POLICY_MODE_CHOOSE)
+ prune_to_recommended(solv, plist);
+}
+
+
+/* check if there is an illegal architecture change if
+ * installed solvable s1 is replaced by s2 */