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composer/src/Composer/DependencyResolver/Solver.php

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Import initial partial port of the libzypp satsolver.
2011-04-05 15:37:19 +00:00
<?php
/*
* This file is part of Composer.
*
* (c) Nils Adermann <naderman@naderman.de>
Fix author/copyright
2011-04-16 12:42:35 +00:00
* Jordi Boggiano <j.boggiano@seld.be>
Import initial partial port of the libzypp satsolver.
2011-04-05 15:37:19 +00:00
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Composer\DependencyResolver;
/**
* @author Nils Adermann <naderman@naderman.de>
*/
class Solver
{
const RULE_INTERNAL_ALLOW_UPDATE = 1;
const RULE_JOB_INSTALL = 2;
const RULE_JOB_REMOVE = 3;
const RULE_JOB_LOCK = 4;
const RULE_NOT_INSTALLABLE = 5;
const RULE_NOTHING_PROVIDES_DEP = 6;
const RULE_PACKAGE_CONFLICT = 7;
const RULE_PACKAGE_NOT_EXIST = 8;
const RULE_PACKAGE_REQUIRES = 9;
const TYPE_PACKAGE = 0;
const TYPE_FEATURE = 1;
const TYPE_UPDATE = 2;
const TYPE_JOB = 3;
const TYPE_WEAK = 4;
const TYPE_LEARNED = 5;
protected $policy;
protected $pool;
protected $installed;
protected $rules;
protected $updateAll;
protected $addedMap = array();
protected $fixMap = array();
protected $updateMap = array();
protected $watches = array();
protected $removeWatches = array();
public function __construct(PolicyInterface $policy, Pool $pool, RepositoryInterface $installed)
{
$this->policy = $policy;
$this->pool = $pool;
$this->installed = $installed;
$this->rules = array(
// order matters here! further down => higher priority
self::TYPE_LEARNED => array(),
self::TYPE_WEAK => array(),
self::TYPE_FEATURE => array(),
self::TYPE_UPDATE => array(),
self::TYPE_JOB => array(),
self::TYPE_PACKAGE => array(),
);
}
/**
* Creates a new rule for the requirements of a package
*
* This rule is of the form (-A|B|C), where B and C are the providers of
* one requirement of the package A.
*
* @param Package $package The package with a requirement
* @param array $providers The providers of the requirement
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the requirement name, that goes with
* the reason
* @return Rule The generated rule or null if tautological
*/
public function createRequireRule(Package $package, array $providers, $reason, $reasonData = null)
{
$literals = array(new Literal($package, false));
foreach ($providers as $provider) {
// self fulfilling rule?
if ($provider === $package) {
return null;
}
$literals[] = new Literal($provider, true);
}
return new Rule($literals, $reason, $reasonData);
}
/**
* Create a new rule for updating a package
*
* If package A1 can be updated to A2 or A3 the rule is (A1|A2|A3).
*
* @param Package $package The package to be updated
* @param array $updates An array of update candidate packages
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the package name, that goes with
* the reason
* @return Rule The generated rule or null if tautology
*/
protected function createUpdateRule(Package $package, array $updates, $reason, $reasonData = null)
{
$literals = array(new Literal($package, true));
foreach ($updates as $update) {
$literals[] = new Literal($update, true);
}
return new Rule($literals, $reason, $reasonData);
}
/**
* Creates a new rule for installing a package
*
* The rule is simply (A) for a package A to be installed.
*
* @param Package $package The package to be installed
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the package name, that goes with
* the reason
* @return Rule The generated rule
*/
public function createInstallRule(Package $package, $reason, $reasonData = null)
{
return new Rule(new Literal($package, true));
}
/**
* Creates a rule to install at least one of a set of packages
*
* The rule is (A|B|C) with A, B and C different packages. If the given
* set of packages is empty an impossible rule is generated.
*
* @param array $packages The set of packages to choose from
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the package name, that goes with
* the reason
* @return Rule The generated rule
*/
public function createInstallOneOfRule(array $packages, $reason, $reasonData = null)
{
if (empty($packages)) {
return $this->createImpossibleRule($reason, $reasonData);
}
$literals = array();
foreach ($packages as $package) {
$literals[] = new Literal($package, true);
}
return new Rule($literals, $reason, $reasonData);
}
/**
* Creates a rule to remove a package
*
* The rule for a package A is (-A).
*
* @param Package $package The package to be removed
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the package name, that goes with
* the reason
* @return Rule The generated rule
*/
public function createRemoveRule(Package $package, $reason, $reasonData = null)
{
return new Rule(array(new Literal($package, false)), $reason, $reasonData);
}
/**
* Creates a rule for two conflicting packages
*
* The rule for conflicting packages A and B is (-A|-B). A is called the issuer
* and B the provider.
*
* @param Package $issuer The package declaring the conflict
* @param Package $provider The package causing the conflict
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the package name, that goes with
* the reason
* @return Rule The generated rule
*/
public function createConflictRule(Package $issuer, Package $provider, $reason, $reasonData = null)
{
// ignore self conflict
if ($issuer === $provider) {
return null;
}
return new Rule(array(new Literal($issuer, false), new Literal($provider, false)), $reason, $reasonData);
}
/**
* Intentionally creates a rule impossible to solve
*
* The rule is an empty one so it can never be satisfied.
*
* @param int $reason A RULE_* constant describing the reason for
* generating this rule
* @param mixed $reasonData Any data, e.g. the package name, that goes with
* the reason
* @return Rule An empty rule
*/
public function createImpossibleRule($reason, $reasonData = null)
{
return new Rule(array(), $reason, $reasonData);
}
/**
* Adds a rule unless it duplicates an existing one of any type
*
* To be able to directly pass in the result of one of the rule creation
* methods the rule may also be null to indicate that no rule should be
* added.
*
* @param int $type A TYPE_* constant defining the rule type
* @param Rule $newRule The rule about to be added
*/
private function addRule($type, Rule $newRule = null) {
if ($newRule) {
foreach ($this->rules as $rules) {
foreach ($rules as $rule) {
if ($rule->equals($newRule)) {
return;
}
}
}
$newRule->setType($type);
$this->rules[$type][] = $newRule;
}
}
public function addRulesForPackage(Package $package)
{
$workQueue = new \SPLQueue;
$workQueue->enqueue($package);
while (!$workQueue->isEmpty()) {
$package = $workQueue->dequeue();
if (isset($this->addedMap[$package->getId()])) {
continue;
}
$this->addedMap[$package->getId()] = true;
$dontFix = 0;
if ($this->installed->contains($package) && !isset($this->fixMap[$package->getId()])) {
$dontFix = 1;
}
if (!$dontFix && !$this->policy->installable($this, $this->pool, $this->installed, $package)) {
$this->addRule(self::TYPE_PACKAGE, $this->createRemoveRule($package, self::RULE_NOT_INSTALLABLE, (string) $package));
continue;
}
foreach ($package->getRequires() as $relation) {
$possibleRequires = $this->pool->whatProvides($relation->getToPackageName(), $relation->getConstraint());
// the strategy here is to not insist on dependencies
// that are already broken. so if we find one provider
// that was already installed, we know that the
// dependency was not broken before so we enforce it
if ($dontFix) {
$foundInstalled = false;
foreach ($possibleRequires as $require) {
if ($this->installed->contains($require)) {
$foundInstalled = true;
break;
}
}
// no installed provider found: previously broken dependency => don't add rule
if (!$foundInstalled) {
continue;
}
}
$this->addRule(self::TYPE_PACKAGE, $this->createRequireRule($package, $possibleRequires, self::RULE_PACKAGE_REQUIRES, (string) $relation));
foreach ($possibleRequires as $require) {
$workQueue->enqueue($require);
}
}
foreach ($package->getConflicts() as $relation) {
$possibleConflicts = $this->pool->whatProvides($relation->getToPackageName(), $relation->getConstraint());
foreach ($possibleConflicts as $conflict) {
if ($dontfix && $this->installed->contains($conflict)) {
continue;
}
$this->addRule(self::TYPE_PACKAGE, $this->createConflictRule($package, $conflict, self::RULE_PACKAGE_CONFLICT, (string) $relation));
}
}
foreach ($package->getRecommends() as $relation) {
foreach ($this->pool->whatProvides($relation->getToPackageName(), $relation->getConstraint()) as $recommend) {
$workQueue->enqueue($recommend);
}
}
foreach ($package->getSuggests() as $relation) {
foreach ($this->pool->whatProvides($relation->getToPackageName(), $relation->getConstraint()) as $suggest) {
$workQueue->enqueue($suggest);
}
}
}
}
/**
* Adds all rules for all update packages of a given package
*
* @param Package $package Rules for this package's updates are to be added
* @param bool $allowAll Whether downgrades are allowed
*/
private function addRulesForUpdatePackages(Package $package, $allowAll)
{
$updates = $this->policy->findUpdatePackages($this, $this->pool, $this->installed, $package, $allowAll);
$this->addRulesForPackage($package);
foreach ($updates as $update) {
$this->addRulesForPackage($update);
}
}
/**
* Sets up watch chains for all rules.
*
* Next1/2 always points to the next rule that is watching the same package.
* The watches array contains rules to start from for each package
*
*/
private function makeWatches()
{
foreach ($this->rules as $type => $rules) {
foreach ($rules as $i => $rule) {
// skip simple assertions of the form (A) or (-A)
if ($rule->isAssertion()) {
continue;
}
if (!isset($this->watches[$rule->watch1])) {
$this->watches[$rule->watch1] = 0;
}
$rule->next1 = $this->watches[$rule->watch1];
$this->watches[$rule->watch1] = $rule;
if (!isset($this->watches[$rule->watch2])) {
$this->watches[$rule->watch2] = 0;
}
$rule->next2 = $this->watches[$rule->watch2];
$this->watches[$rule->watch2] = $rule;
}
}
}
private function findDecisionRule(Package $package)
{
foreach ($this->decisionQueue as $i => $literal) {
if ($package === $literal->getPackage()) {
return $this->decisionQueueWhy[$i];
}
}
return null;
}
private function makeAssertionRuleDecisions()
{
// do we need to decide a SYSTEMSOLVABLE at level 1?
foreach ($this->rules as $type => $rules) {
if (self::TYPE_WEAK === $type) {
continue;
}
foreach ($rules as $rule) {
if (!$rule->isAssertion() || $rule->isDisabled()) {
continue;
}
$literals = $rule->getLiterals();
$literal = $literals[0];
if (!$this->decided($literal->getPackage())) {
}
if ($this->decisionsSatisfy($literal)) {
continue;
}
// found a conflict
if (self::TYPE_LEARNED === $type) {
$rule->disable();
}
$conflict = $this->findDecisionRule($literal->getPackage());
// todo: handle conflict with systemsolvable?
if (self::TYPE_PACKAGE === $conflict->getType()) {
}
}
}
foreach ($this->rules[self::TYPE_WEAK] as $rule) {
if (!$rule->isAssertion() || $rule->isDisabled()) {
continue;
}
if ($this->decisionsSatisfy($literals[0])) {
continue;
}
// conflict, but this is a weak rule => disable
$rule->disable();
}
}
public function solve(Request $request)
{
$this->jobs = $request->getJobs();
$installedPackages = $this->installed->getPackages();
foreach ($this->jobs as $job) {
switch ($job['cmd']) {
case 'update-all':
foreach ($installedPackages as $package) {
$this->updateMap[$package->getId()] = true;
}
break;
case 'fix-all':
foreach ($installedPackages as $package) {
$this->fixMap[$package->getId()] = true;
}
break;
}
foreach ($job['packages'] as $package) {
switch ($job['cmd']) {
case 'fix':
if ($this->installed->contains($package)) {
$this->fixMap[$package->getId()] = true;
}
break;
case 'update':
if ($this->installed->contains($package)) {
$this->updateMap[$package->getId()] = true;
}
break;
}
}
}
foreach ($installedPackages as $package) {
$this->addRulesForPackage($package);
}
foreach ($installedPackages as $package) {
$this->addRulesForUpdatePackages($package, true);
}
foreach ($this->jobs as $job) {
foreach ($job['packages'] as $package) {
switch ($job['cmd']) {
case 'install':
$this->installCandidateMap[$package->getId()] = true;
$this->addRulesForPackage($package);
break;
}
}
}
// solver_addrpmrulesforweak(solv, &addedmap);
/*
* first pass done, we now have all the rpm 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
*/
// solver_unifyrules(solv); /* remove duplicate rpm rules */
// no idea what this is
// /* create dup maps if needed. We need the maps early to create our
// * update rules */
// if (hasdupjob)
// solver_createdupmaps(solv);
foreach ($installedPackages as $package) {
// create a feature rule which allows downgrades
$updates = $this->policy->findUpdatePackages($this, $this->pool, $this->installed, $package, true);
$featureRule = $this->createUpdateRule($package, $updates, self::RULE_INTERNAL_ALLOW_UPDATE, (string) $package);
// create an update rule which does not allow downgrades
$updates = $this->policy->findUpdatePackages($this, $this->pool, $this->installed, $package, false);
$rule = $this->createUpdateRule($package, $updates, self::RULE_INTERNAL_ALLOW_UPDATE, (string) $package);
if ($rule->equals($featureRule)) {
if ($this->policy->allowUninstall()) {
$this->addRule(self::TYPE_WEAK, $featureRule);
} else {
$this->addRule(self::TYPE_UPDATE, $rule);
}
} else if ($this->policy->allowUninstall()) {
$this->addRule(self::TYPE_WEAK, $featureRule);
$this->addRule(self::TYPE_WEAK, $rule);
}
}
foreach ($this->jobs as $job) {
switch ($job['cmd']) {
case 'install':
$rule = $this->createInstallOneOfRule($job['packages'], self::RULE_JOB_INSTALL, $job['packageName']);
$this->addRule(self::TYPE_JOB, $rule);
//$this->ruleToJob[$rule] = $job;
break;
case 'remove':
// remove all packages with this name including uninstalled
// ones to make sure none of them are picked as replacements
// todo: cleandeps
foreach ($job['packages'] as $package) {
$rule = $this->createRemoveRule($package, self::RULE_JOB_REMOVE);
$this->addRule(self::TYPE_JOB, $rule);
//$this->ruleToJob[$rule] = $job;
}
break;
case 'lock':
foreach ($job['packages'] as $package) {
if ($this->installed->contains($package)) {
$rule = $this->createInstallRule($package, self::RULE_JOB_LOCK);
} else {
$rule = $this->createRemoveRule($package, self::RULE_JOB_LOCK);
}
$this->addRule(self::TYPE_JOB, $rule);
//$this->ruleToJob[$rule] = $job;
}
break;
}
}
// solver_addchoicerules(solv);
$this->makeWatches();
/* disable update rules that conflict with our job */
//solver_disablepolicyrules(solv);
/* make decisions based on job/update assertions */
$this->makeAssertionRuleDecisions();
$installRecommended = 0;
$this->runSat(true, $installRecommended);
//findrecommendedsuggested(solv);
//solver_prepare_solutions(solv);
//transaction_calculate(&solv->trans, &solv->decisionq, &solv->noobsoletes);
}
public function printRules()
{
print "\n";
foreach ($this->rules as $type => $rules) {
print $type . ": ";
foreach ($rules as $rule) {
print $rule;
}
print "\n";
}
}
protected $decisionQueue = array();
protected $propagateIndex;
protected $decisionMap = array();
protected $branches = array();
protected function addDecision(Literal $l, $level)
{
if ($l->isWanted()) {
$this->decisionMap[$l->getPackageId()] = $level;
} else {
$this->decisionMap[$l->getPackageId()] = -$level;
}
}
protected function decisionsContain(Literal $l)
{
return (isset($this->decisionMap[$l->getPackageId()]) && (
$this->decisionMap[$l->getPackageId()] > 0 && $l->isWanted() ||
$this->decisionMap[$l->getPackageId()] < 0 && !$l->isWanted()
));
}
protected function decisionsSatisfy(Literal $l)
{
return ($l->isWanted() && isset($this->decisionMap[$l->getPackageId()]) && $this->decisionMap[$l->getPackageId()] > 0) ||
(!$l->isWanted() && (!isset($this->decisionMap[$l->getPackageId()]) || $this->decisionMap[$l->getPackageId()] < 0));
}
protected function decisionsConflict(Literal $l)
{
return (isset($this->decisionMap[$l->getPackageId()]) && (
$this->decisionMap[$l->getPackageId()] > 0 && !$l->isWanted() ||
$this->decisionMap[$l->getPackageId()] < 0 && $l->isWanted()
));
}
protected function decided(Package $p)
{
return isset($this->decisionMap[$p->getId()]);
}
protected function undecided(Package $p)
{
return !isset($this->decisionMap[$p->getId()]);
}
protected function decidedInstall(Package $p) {
return isset($this->decisionMap[$p->getId()]) && $this->decisionMap[$p->getId()] > 0;
}
protected function decidedRemove(Package $p) {
return isset($this->decisionMap[$p->getId()]) && $this->decisionMap[$p->getId()] < 0;
}
/**
* Makes a decision and propagates it to all rules.
*
* Evaluates each term affected by the decision (linked through watches)
* If we find unit rules we make new decisions based on them
*
* @return Rule|null A rule on conflict, otherwise null.
*/
protected function propagate($level)
{
while ($this->propagateIndex < count($this->decisionQueue)) {
// we invert the decided literal here, example:
// A was decided => (-A|B) now requires B to be true, so we look for
// rules which are fulfilled by -A, rather than A.
$literal = $this->decisionQueue[$this->propagateIndex]->inverted();
$this->propagateIndex++;
// /* foreach rule where 'pkg' is now FALSE */
//for (rp = watches + pkg; *rp; rp = next_rp)
for ($rule = $this->watches[$literal->getId()]; $rule !== null; $rule = $nextRule) {
$nextRule = $rule->getNext($literal);
if ($rule->isDisabled()) {
continue;
}
$otherWatch = $rule->getOtherWatch($literal);
if ($this->decisionsContain($otherWatch)) {
continue;
}
$ruleLiterals = $rule->getLiterals();
if (sizeof($ruleLiterals) > 2) {
foreach ($ruleLiterals as $ruleLiteral) {
if (!$otherWatch->equals($ruleLiteral) &&
!$this->decisionsConflict($ruleLiteral)) {
if ($literal->equals($rule->getWatch1())) {
$rule->setWatch1($ruleLiteral);
$rule->setNext1($rule);
} else {
$rule->setWatch2($ruleLiteral);
$rule->setNext2($rule);
}
$this->watches[$ruleLiteral->getId()] = $rule;
continue 2;
}
}
}
// yay, we found a unit clause! try setting it to true
if ($this->decisionsConflict($otherWatch)) {
return $rule;
}
$this->addDecision($otherWatch, $level);
$this->decisionQueue[] = $otherWatch;
$this->decisionQueueWhy[] = $rule;
}
}
return null;
}
private function setPropagateLearn($level, Literal $literal, $disableRules, Rule $rule)
{
return 0;
}
private function selectAndInstall($level, array $decisionQueue, $disableRules, Rule $rule)
{
// choose best package to install from decisionQueue
$literals = $this->policy->selectPreferedPackages($decisionQueue);
// if there are multiple candidates, then branch
if (count($literals) > 1) {
foreach ($literals as $i => $literal) {
if (0 !== $i) {
$this->branches[] = array($literal, $level);
}
}
}
return $this->setPropagateLearn($level, $literals[0], $disableRules, $rule);
}
private function runSat($disableRules = true, $installRecommended = false)
{
$this->propagateIndex = 0;
// /*
// * here's the main loop:
// * 1) propagate new decisions (only needed once)
// * 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
// */
$decisionQueue = array();
$decisionSupplementQueue = array();
$disableRules = array();
$level = 1;
$systemLevel = $level + 1;
$minimizationsteps = 0;
$installedPos = 0;
$this->installedPackages = array_values($this->installed->getPackages());
while (true) {
$conflictRule = $this->propagate($level);
if ($conflictRule !== null) {
// if (analyze_unsolvable(solv, r, disablerules))
if ($this->analyzeUnsolvable($conflictRule, $disableRules)) {
continue;
} else {
return;
}
}
// handle job rules
if ($level < $systemLevel) {
$ruleIndex = 0;
foreach ($this->rules[self::TYPE_JOB] as $ruleIndex => $rule) {
if ($rule->isEnabled()) {
$decisionQueue = array();
$noneSatisfied = true;
foreach ($rule->getLiterals() as $literal) {
if ($this->decisionsSatisfy($literal)) {
$noneSatisfied = false;
break;
}
$decisionQueue[] = $literal;
}
if ($noneSatisfied && count($decisionQueue)) {
// prune all update packages until installed version
// except for requested updates
if (count($this->installed) != count($this->updateMap)) {
$prunedQueue = array();
foreach ($decisionQueue as $literal) {
if ($this->installed->contains($literal->getPackage())) {
$prunedQueue[] = $literal;
if (isset($this->updateMap[$literal->getPackageId()])) {
$prunedQueue = $decisionQueue;
break;
}
}
}
$decisionQueue = $prunedQueue;
}
}
if ($noneSatisfied && count($decisionQueue)) {
$oLevel = $level;
$level = $this->selectAndInstall($level, $decisionQueue, $disableRules, $rule);
if (0 === $level) {
return;
}
if ($level <= $oLevel) {
break;
}
}
}
}
$systemLevel = $level + 1;
// jobs left
if ($ruleIndex + 1 < count($this->rules[Solver::TYPE_JOB])) {
continue;
}
}
// handle installed packages
if ($level < $systemLevel) {
// use two passes if any packages are being updated
// -> better user experience
for ($pass = (count($this->updateMap)) ? 0 : 1; $pass < 2; $pass++) {
$passLevel = $level;
for ($i = $installedPos, $n = 0; $n < count($this->installedPackages); $i++, $n++) {
$repeat = false;
if ($i == count($this->installedPackages)) {
$i = 0;
}
$literal = new Literal($this->installedPackages[$i], true);
if ($this->decisionsContain($literal)) {
continue;
}
// only process updates in first pass
if (0 === $pass && !isset($this->updateMap[$literal->getPackageId()])) {
continue;
}
$rule = null;
if (isset($this->rules[Solver::TYPE_UPDATE][$literal->getPackageId()])) {
$rule = $this->rules[Solver::TYPE_UPDATE][$literal->getPackageId()];
}
if ((!$rule || $rule->isDisabled()) && isset($this->rules[Solver::TYPE_FEATURE][$literal->getPackageId()])) {
$rule = $this->rules[Solver::TYPE_FEATURE][$literal->getPackageId()];
}
if (!$rule || $rule->isDisabled()) {
continue;
}
$decisionQueue = array();
if (!isset($this->noUpdate[$literal->getPackageId()]) && (
$this->decidedRemove($literal->getPackage()) ||
isset($this->updateMap[$literal->getPackageId()]) ||
!$literal->equals($rule->getFirstLiteral())
)) {
foreach ($rule->getLiterals() as $ruleLiteral) {
if ($this->decidedInstall($ruleLiteral->getPackage())) {
// already fulfilled
break;
}
if ($this->undecided($ruleLiteral->getPackage())) {
$decisionQueue[] = $ruleLiteral;
}
}
}
if (sizeof($decisionQueue)) {
$oLevel = $level;
$level = $this->selectAndInstall($level, $decisionQueue, $disableRules, $rule);
if (0 === $level) {
return;
}
if ($level <= $oLevel) {
$repeat = true;
}
}
// still undecided? keep package.
if (!$repeat && $this->undecided($literal->getPackage())) {
$oLevel = $level;
if (isset($this->cleanDepsMap[$literal->getPackageId()])) {
// clean deps removes package
$level = $this->setPropagateLearn($level, $literal->invert(), $disableRules, null);
} else {
// ckeeping package
$level = $this->setPropagateLearn($level, $literal, $disableRules, $rule);
}
if (0 === $level) {
return;
}
if ($level <= $oLevel) {
$repeat = true;
}
}
if ($repeat) {
if (1 === $level || $level < $passLevel) {
// trouble
break;
}
if ($level < $oLevel) {
// redo all
$n = 0;
}
// repeat
$i--;
$n--;
continue;
}
}
if ($n < count($this->installedPackages)) {
$installedPos = $i; // retry this problem next time
break;
}
$installedPos = 0;
}
$systemlevel = $level + 1;
if ($pass < 2) {
// had trouble => retry
continue;
}
}
if ($level < $systemLevel) {
$systemLevel = $level;
}
foreach ($this->rules as $ruleType => $rules) {
foreach ($rules as $rule) {
if ($rule->isEnabled()) {
$decisionQueue = array();
}
}
}
$this->printRules();
//
// /*
// * decide
// */
// POOL_DEBUG(SAT_DEBUG_POLICY, "deciding unresolved rules\n");
// for (i = 1, n = 1; n < solv->nrules; i++, n++)
// {
// if (i == solv->nrules)
// i = 1;
// r = solv->rules + i;
// if (r->d < 0) /* ignore disabled rules */
// continue;
// queue_empty(&dq);
// if (r->d == 0)
// {
// /* binary or unary rule */
// /* need two positive undecided literals */
// if (r->p < 0 || 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
// */
// if (r->p < 0)
// {
// if (solv->decisionmap[-r->p] <= 0)
// continue;
// }
// else
// {
// 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 (SAT_DEBUG_PROPAGATE)
// {
// POOL_DEBUG(SAT_DEBUG_PROPAGATE, "unfulfilled ");
// solver_printruleclass(solv, SAT_DEBUG_PROPAGATE, r);
// }
// /* dq.count < 2 cannot happen as this means that
// * the rule is unit */
// assert(dq.count > 1);
//
// olevel = level;
// level = selectandinstall(solv, level, &dq, disablerules, r - solv->rules);
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// if (level < systemlevel || level == 1)
// break; /* trouble */
// /* something changed, so look at all rules again */
// n = 0;
// }
//
// if (n != solv->nrules) /* ran into trouble, restart */
// continue;
//
// /* at this point we have a consistent system. now do the extras... */
//
}
}
// 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, j, n;
// Solvable *s;
// Pool *pool = solv->pool;
// Id p, *dp;
// int minimizationsteps;
// int installedpos = solv->installed ? solv->installed->start : 0;
//
// IF_POOLDEBUG (SAT_DEBUG_RULE_CREATION)
// {
// POOL_DEBUG (SAT_DEBUG_RULE_CREATION, "number of rules: %d\n", solv->nrules);
// for (i = 1; i < solv->nrules; i++)
// solver_printruleclass(solv, SAT_DEBUG_RULE_CREATION, solv->rules + i);
// }
//
// POOL_DEBUG(SAT_DEBUG_SOLVER, "initial decisions: %d\n", solv->decisionq.count);
//
// IF_POOLDEBUG (SAT_DEBUG_SCHUBI)
// solver_printdecisions(solv);
//
// /* start SAT algorithm */
// level = 1;
// systemlevel = level + 1;
// POOL_DEBUG(SAT_DEBUG_SOLVER, "solving...\n");
//
// queue_init(&dq);
// queue_init(&dqs);
//
// /*
// * here's the main loop:
// * 1) propagate new decisions (only needed once)
// * 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 == 1)
// {
// POOL_DEBUG(SAT_DEBUG_PROPAGATE, "propagating (propagate_index: %d; size decisionq: %d)...\n", solv->propagate_index, solv->decisionq.count);
// if ((r = propagate(solv, level)) != 0)
// {
// if (analyze_unsolvable(solv, r, disablerules))
// continue;
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// }
//
// /*
// * resolve jobs first
// */
// if (level < systemlevel)
// {
// POOL_DEBUG(SAT_DEBUG_SOLVER, "resolving job rules\n");
// for (i = solv->jobrules, r = solv->rules + i; i < solv->jobrules_end; i++, r++)
// {
// Id l;
// if (r->d < 0) /* ignore disabled rules */
// continue;
// queue_empty(&dq);
// FOR_RULELITERALS(l, dp, 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)
// {
// int j, k;
// for (j = k = 0; j < dq.count; j++)
// {
// Solvable *s = pool->solvables + dq.elements[j];
// if (s->repo == solv->installed)
// {
// dq.elements[k++] = dq.elements[j];
// if (solv->updatemap.size && MAPTST(&solv->updatemap, dq.elements[j] - solv->installed->start))
// {
// k = 0; /* package wants to be updated, do not prune */
// break;
// }
// }
// }
// if (k)
// dq.count = k;
// }
// olevel = level;
// level = selectandinstall(solv, level, &dq, disablerules, i);
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// if (level <= olevel)
// break;
// }
// systemlevel = level + 1;
// if (i < solv->jobrules_end)
// continue;
// }
//
//
// /*
// * installed packages
// */
// if (level < systemlevel && solv->installed && solv->installed->nsolvables && !solv->installed->disabled)
// {
// Repo *installed = solv->installed;
// int pass;
//
// POOL_DEBUG(SAT_DEBUG_SOLVER, "resolving installed packages\n");
// /* 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; pass++)
// {
// int passlevel = level;
// /* start with installedpos, the position that gave us problems last time */
// for (i = installedpos, n = installed->start; n < installed->end; i++, n++)
// {
// Rule *rr;
// Id d;
//
// if (i == installed->end)
// i = installed->start;
// s = pool->solvables + i;
// if (s->repo != installed)
// continue;
//
// if (solv->decisionmap[i] > 0)
// continue;
// 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 */
//
// /* XXX: noupdate check is probably no longer needed, as all jobs should
// * already be satisfied */
// /* Actually we currently still need it because of erase jobs */
// /* if noupdate is set we do not look at update candidates */
// 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 != i))
// {
// if (solv->noobsoletes.size && solv->multiversionupdaters
// && (d = solv->multiversionupdaters[i - installed->start]) != 0)
// {
// /* special multiversion handling, make sure best version is chosen */
// queue_push(&dq, i);
// while ((p = pool->whatprovidesdata[d++]) != 0)
// if (solv->decisionmap[p] >= 0)
// queue_push(&dq, p);
// 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 */
// FOR_RULELITERALS(p, dp, rr)
// {
// if (solv->decisionmap[p] > 0)
// {
// dq.count = 0; /* already fulfilled */
// break;
// }
// if (!solv->decisionmap[p])
// queue_push(&dq, p);
// }
// }
// }
// /* install best version */
// if (dq.count)
// {
// olevel = level;
// level = selectandinstall(solv, level, &dq, disablerules, rr - solv->rules);
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// if (level <= olevel)
// {
// if (level == 1 || 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))
// {
// POOL_DEBUG(SAT_DEBUG_POLICY, "cleandeps erasing %s\n", solvid2str(pool, i));
// level = setpropagatelearn(solv, level, -i, disablerules, 0);
// }
// else
// {
// POOL_DEBUG(SAT_DEBUG_POLICY, "keeping %s\n", solvid2str(pool, i));
// level = setpropagatelearn(solv, level, i, disablerules, r - solv->rules);
// }
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// if (level <= olevel)
// {
// if (level == 1 || 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 */
// break; /* ran into trouble */
// }
// installedpos = installed->start; /* reset installedpos */
// }
// systemlevel = level + 1;
// if (pass < 2)
// continue; /* had trouble, retry */
// }
//
// if (level < systemlevel)
// systemlevel = level;
//
// /*
// * decide
// */
// POOL_DEBUG(SAT_DEBUG_POLICY, "deciding unresolved rules\n");
// for (i = 1, n = 1; n < solv->nrules; i++, n++)
// {
// if (i == solv->nrules)
// i = 1;
// r = solv->rules + i;
// if (r->d < 0) /* ignore disabled rules */
// continue;
// queue_empty(&dq);
// if (r->d == 0)
// {
// /* binary or unary rule */
// /* need two positive undecided literals */
// if (r->p < 0 || 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
// */
// if (r->p < 0)
// {
// if (solv->decisionmap[-r->p] <= 0)
// continue;
// }
// else
// {
// 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 (SAT_DEBUG_PROPAGATE)
// {
// POOL_DEBUG(SAT_DEBUG_PROPAGATE, "unfulfilled ");
// solver_printruleclass(solv, SAT_DEBUG_PROPAGATE, r);
// }
// /* dq.count < 2 cannot happen as this means that
// * the rule is unit */
// assert(dq.count > 1);
//
// olevel = level;
// level = selectandinstall(solv, level, &dq, disablerules, r - solv->rules);
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// if (level < systemlevel || level == 1)
// break; /* trouble */
// /* something changed, so look at all rules again */
// n = 0;
// }
//
// if (n != solv->nrules) /* ran into trouble, restart */
// continue;
//
// /* at this point we have a consistent system. now do the extras... */
//
// if (doweak)
// {
// int qcount;
//
// POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended packages\n");
// queue_empty(&dq); /* recommended packages */
// queue_empty(&dqs); /* supplemented packages */
// for (i = 1; i < pool->nsolvables; i++)
// {
// if (solv->decisionmap[i] < 0)
// continue;
// if (solv->decisionmap[i] > 0)
// {
// /* installed, check for recommends */
// Id *recp, rec, pp, p;
// s = pool->solvables + i;
// if (solv->ignorealreadyrecommended && s->repo == solv->installed)
// continue;
// /* XXX need to special case AND ? */
// if (s->recommends)
// {
// recp = s->repo->idarraydata + s->recommends;
// while ((rec = *recp++) != 0)
// {
// qcount = dq.count;
// FOR_PROVIDES(p, pp, rec)
// {
// if (solv->decisionmap[p] > 0)
// {
// dq.count = qcount;
// break;
// }
// else if (solv->decisionmap[p] == 0)
// {
// queue_pushunique(&dq, p);
// }
// }
// }
// }
// }
// else
// {
// s = pool->solvables + i;
// if (!s->supplements)
// continue;
// if (!pool_installable(pool, s))
// continue;
// if (!solver_is_supplementing(solv, s))
// continue;
// queue_push(&dqs, i);
// }
// }
//
// /* filter out all packages obsoleted by installed packages */
// /* this is no longer needed if we have 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->noobsoletes.size && MAPTST(&solv->noobsoletes, p))
// continue;
// obsp = s->repo->idarraydata + s->obsoletes;
// /* foreach obsoletes */
// while ((obs = *obsp++) != 0)
// FOR_PROVIDES(po, ppo, obs)
// 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->ignorealreadyrecommended && dqs.count)
// {
// /* turn off all new packages */
// for (i = 0; i < solv->decisionq.count; i++)
// {
// p = solv->decisionq.elements[i];
// if (p < 0)
// continue;
// s = pool->solvables + p;
// if (s->repo && s->repo != solv->installed)
// solv->decisionmap[p] = -solv->decisionmap[p];
// }
// /* filter out old supplements */
// for (i = j = 0; i < dqs.count; i++)
// {
// p = dqs.elements[i];
// s = pool->solvables + p;
// if (!s->supplements)
// continue;
// if (!solver_is_supplementing(solv, s))
// dqs.elements[j++] = p;
// }
// dqs.count = j;
// /* undo turning off */
// for (i = 0; i < solv->decisionq.count; i++)
// {
// p = solv->decisionq.elements[i];
// if (p < 0)
// continue;
// s = pool->solvables + p;
// if (s->repo && s->repo != solv->installed)
// solv->decisionmap[p] = -solv->decisionmap[p];
// }
// }
//
// /* 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->noobsoletes.size)
// {
// for (i = j = 0; i < dqs.count; i++)
// {
// p = dqs.elements[i];
// if (MAPTST(&solv->noobsoletes, 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;
// }
//
// /* 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)
// {
// Map dqmap;
// int decisioncount = solv->decisionq.count;
//
// if (dq.count == 1)
// {
// /* simple case, just one package. no need to choose */
// p = dq.elements[0];
// if (dqs.count)
// POOL_DEBUG(SAT_DEBUG_POLICY, "installing supplemented %s\n", solvid2str(pool, p));
// else
// POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended %s\n", solvid2str(pool, p));
// queue_push(&solv->recommendations, p);
// level = setpropagatelearn(solv, level, p, 0, 0);
// continue; /* back to main loop */
// }
//
// /* 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]);
//
// /* install all supplemented packages */
// for (i = 0; i < dqs.count; i++)
// {
// p = dqs.elements[i];
// if (solv->decisionmap[p] || !MAPTST(&dqmap, p))
// continue;
// POOL_DEBUG(SAT_DEBUG_POLICY, "installing supplemented %s\n", solvid2str(pool, p));
// queue_push(&solv->recommendations, p);
// olevel = level;
// level = setpropagatelearn(solv, level, p, 0, 0);
// if (level <= olevel)
// break;
// }
// if (i < dqs.count || solv->decisionq.count < decisioncount)
// {
// map_free(&dqmap);
// continue;
// }
//
// /* 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->ignorealreadyrecommended && s->repo == solv->installed))
// continue;
// if (!s->recommends)
// continue;
// recp = s->repo->idarraydata + s->recommends;
// while ((rec = *recp++) != 0)
// {
// queue_empty(&dq);
// FOR_PROVIDES(p, pp, rec)
// {
// if (solv->decisionmap[p] > 0)
// {
// dq.count = 0;
// break;
// }
// else if (solv->decisionmap[p] == 0 && MAPTST(&dqmap, p))
// queue_pushunique(&dq, p);
// }
// if (!dq.count)
// continue;
// if (dq.count > 1)
// {
// /* multiple candidates, open a branch */
// for (i = 1; i < dq.count; i++)
// queue_push(&solv->branches, dq.elements[i]);
// queue_push(&solv->branches, -level);
// }
// p = dq.elements[0];
// POOL_DEBUG(SAT_DEBUG_POLICY, "installing recommended %s\n", solvid2str(pool, p));
// queue_push(&solv->recommendations, p);
// olevel = level;
// level = setpropagatelearn(solv, level, p, 0, 0);
// 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);
//
// continue; /* back to main loop so that all deps are checked */
// }
// }
//
// if (solv->dupmap_all && solv->installed)
// {
// int installedone = 0;
//
// /* let's see if we can install some unsupported package */
// POOL_DEBUG(SAT_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 */
// olevel = level;
// if (solv->droporphanedmap_all)
// continue;
// if (solv->droporphanedmap.size && MAPTST(&solv->droporphanedmap, p - solv->installed->start))
// continue;
// POOL_DEBUG(SAT_DEBUG_SOLVER, "keeping orphaned %s\n", solvid2str(pool, p));
// level = setpropagatelearn(solv, level, p, 0, 0);
// installedone = 1;
// if (level < olevel)
// break;
// }
// if (installedone || i < solv->orphaned.count)
// continue; /* back to main loop */
// for (i = 0; i < solv->orphaned.count; i++)
// {
// p = solv->orphaned.elements[i];
// if (solv->decisionmap[p])
// continue; /* already decided */
// POOL_DEBUG(SAT_DEBUG_SOLVER, "removing orphaned %s\n", solvid2str(pool, p));
// olevel = level;
// level = setpropagatelearn(solv, level, -p, 0, 0);
// if (level < olevel)
// break;
// }
// if (i < solv->orphaned.count)
// continue; /* back to main loop */
// }
//
// if (solv->solution_callback)
// {
// solv->solution_callback(solv, solv->solution_callback_data);
// if (solv->branches.count)
// {
// int i = solv->branches.count - 1;
// int l = -solv->branches.elements[i];
// Id why;
//
// for (; i > 0; i--)
// if (solv->branches.elements[i - 1] < 0)
// break;
// p = solv->branches.elements[i];
// POOL_DEBUG(SAT_DEBUG_SOLVER, "branching with %s\n", solvid2str(pool, p));
// queue_empty(&dq);
// for (j = i + 1; j < solv->branches.count; j++)
// queue_push(&dq, solv->branches.elements[j]);
// solv->branches.count = i;
// level = l;
// revert(solv, level);
// if (dq.count > 1)
// for (j = 0; j < dq.count; j++)
// queue_push(&solv->branches, dq.elements[j]);
// olevel = level;
// why = -solv->decisionq_why.elements[solv->decisionq_why.count];
// assert(why >= 0);
// level = setpropagatelearn(solv, level, p, disablerules, why);
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// continue;
// }
// /* all branches done, we're finally finished */
// break;
// }
//
// /* minimization step */
// if (solv->branches.count)
// {
// int l = 0, lasti = -1, lastl = -1;
// Id why;
//
// p = 0;
// for (i = solv->branches.count - 1; i >= 0; i--)
// {
// p = solv->branches.elements[i];
// if (p < 0)
// l = -p;
// else if (p > 0 && solv->decisionmap[p] > l + 1)
// {
// lasti = i;
// lastl = l;
// }
// }
// if (lasti >= 0)
// {
// /* kill old solvable so that we do not loop */
// p = solv->branches.elements[lasti];
// solv->branches.elements[lasti] = 0;
// POOL_DEBUG(SAT_DEBUG_SOLVER, "minimizing %d -> %d with %s\n", solv->decisionmap[p], lastl, solvid2str(pool, p));
// minimizationsteps++;
//
// level = lastl;
// revert(solv, level);
// why = -solv->decisionq_why.elements[solv->decisionq_why.count];
// assert(why >= 0);
// olevel = level;
// level = setpropagatelearn(solv, level, p, disablerules, why);
// if (level == 0)
// {
// queue_free(&dq);
// queue_free(&dqs);
// return;
// }
// continue; /* back to main loop */
// }
// }
// /* no minimization found, we're finally finished! */
// break;
// }
//
// POOL_DEBUG(SAT_DEBUG_STATS, "solver statistics: %d learned rules, %d unsolvable, %d minimization steps\n", solv->stats_learned, solv->stats_unsolvable, minimizationsteps);
//
// POOL_DEBUG(SAT_DEBUG_STATS, "done solving.\n\n");
// queue_free(&dq);
// queue_free(&dqs);
// #if 0
// solver_printdecisionq(solv, SAT_DEBUG_RESULT);
// #endif
// }
}