]> git.saurik.com Git - apt.git/blobdiff - apt-pkg/algorithms.cc
TransactionManager can never be a nullptr
[apt.git] / apt-pkg / algorithms.cc
index a3963d546d17dd7baa41709819e6ef227ccb9872..fbc809ed0ece88c22387785e4c7b13f024180435 100644 (file)
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
+#include <config.h>
+
 #include <apt-pkg/algorithms.h>
 #include <apt-pkg/error.h>
 #include <apt-pkg/configuration.h>
-#include <apt-pkg/version.h>
-#include <apt-pkg/sptr.h>
-#include <apt-pkg/acquire-item.h>
-    
-#include <apti18n.h>
-#include <sys/types.h>
+#include <apt-pkg/edsp.h>
+#include <apt-pkg/depcache.h>
+#include <apt-pkg/packagemanager.h>
+#include <apt-pkg/pkgcache.h>
+#include <apt-pkg/cacheiterators.h>
+#include <apt-pkg/prettyprinters.h>
+
+#include <string.h>
+#include <string>
 #include <cstdlib>
-#include <algorithm>
 #include <iostream>
+
+#include <apti18n.h>
                                                                        /*}}}*/
 using namespace std;
 
-pkgProblemResolver *pkgProblemResolver::This = 0;
-
 // Simulate::Simulate - Constructor                                    /*{{{*/
 // ---------------------------------------------------------------------
 /* The legacy translations here of input Pkg iterators is obsolete, 
    this is not necessary since the pkgCaches are fully shared now. */
 pkgSimulate::pkgSimulate(pkgDepCache *Cache) : pkgPackageManager(Cache),
-                           iPolicy(Cache),
+                           d(NULL), iPolicy(Cache),
                            Sim(&Cache->GetCache(),&iPolicy),
                            group(Sim)
 {
@@ -50,6 +54,12 @@ pkgSimulate::pkgSimulate(pkgDepCache *Cache) : pkgPackageManager(Cache),
       FileNames[I] = Jnk;
 }
                                                                        /*}}}*/
+// Simulate::~Simulate - Destructor                                    /*{{{*/
+pkgSimulate::~pkgSimulate()
+{
+   delete[] Flags;
+}
+                                                                       /*}}}*/
 // Simulate::Describe - Describe a package                             /*{{{*/
 // ---------------------------------------------------------------------
 /* Parameter Current == true displays the current package version,
@@ -58,7 +68,7 @@ void pkgSimulate::Describe(PkgIterator Pkg,ostream &out,bool Current,bool Candid
 {
    VerIterator Ver(Sim);
  
-   out << Pkg.Name();
+   out << Pkg.FullName(true);
 
    if (Current == true)
    {
@@ -83,15 +93,15 @@ void pkgSimulate::Describe(PkgIterator Pkg,ostream &out,bool Current,bool Candid
 bool pkgSimulate::Install(PkgIterator iPkg,string /*File*/)
 {
    // Adapt the iterator
-   PkgIterator Pkg = Sim.FindPkg(iPkg.Name());
+   PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
    Flags[Pkg->ID] = 1;
    
    cout << "Inst ";
    Describe(Pkg,cout,true,true);
    Sim.MarkInstall(Pkg,false);
-   
+
    // Look for broken conflicts+predepends.
-   for (PkgIterator I = Sim.PkgBegin(); I.end() == false; I++)
+   for (PkgIterator I = Sim.PkgBegin(); I.end() == false; ++I)
    {
       if (Sim[I].InstallVer == 0)
         continue;
@@ -101,16 +111,14 @@ bool pkgSimulate::Install(PkgIterator iPkg,string /*File*/)
         DepIterator Start;
         DepIterator End;
         D.GlobOr(Start,End);
-        if (Start->Type == pkgCache::Dep::Conflicts ||
-            Start->Type == pkgCache::Dep::DpkgBreaks ||
-            Start->Type == pkgCache::Dep::Obsoletes ||
+        if (Start.IsNegative() == true ||
             End->Type == pkgCache::Dep::PreDepends)
          {
            if ((Sim[End] & pkgDepCache::DepGInstall) == 0)
            {
-              cout << " [" << I.Name() << " on " << Start.TargetPkg().Name() << ']';
+              cout << " [" << I.FullName(false) << " on " << Start.TargetPkg().FullName(false) << ']';
               if (Start->Type == pkgCache::Dep::Conflicts)
-                 _error->Error("Fatal, conflicts violated %s",I.Name());
+                 _error->Error("Fatal, conflicts violated %s",I.FullName(false).c_str());
            }       
         }
       }      
@@ -131,35 +139,35 @@ bool pkgSimulate::Install(PkgIterator iPkg,string /*File*/)
 bool pkgSimulate::Configure(PkgIterator iPkg)
 {
    // Adapt the iterator
-   PkgIterator Pkg = Sim.FindPkg(iPkg.Name());
+   PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
    
    Flags[Pkg->ID] = 2;
-//   Sim.MarkInstall(Pkg,false);
+
    if (Sim[Pkg].InstBroken() == true)
    {
-      cout << "Conf " << Pkg.Name() << " broken" << endl;
+      cout << "Conf " << Pkg.FullName(false) << " broken" << endl;
 
       Sim.Update();
       
       // Print out each package and the failed dependencies
-      for (pkgCache::DepIterator D = Sim[Pkg].InstVerIter(Sim).DependsList(); D.end() == false; D++)
+      for (pkgCache::DepIterator D = Sim[Pkg].InstVerIter(Sim).DependsList(); D.end() == false; ++D)
       {
         if (Sim.IsImportantDep(D) == false || 
             (Sim[D] & pkgDepCache::DepInstall) != 0)
            continue;
         
         if (D->Type == pkgCache::Dep::Obsoletes)
-           cout << " Obsoletes:" << D.TargetPkg().Name();
+           cout << " Obsoletes:" << D.TargetPkg().FullName(false);
         else if (D->Type == pkgCache::Dep::Conflicts)
-           cout << " Conflicts:" << D.TargetPkg().Name();
+           cout << " Conflicts:" << D.TargetPkg().FullName(false);
         else if (D->Type == pkgCache::Dep::DpkgBreaks)
-           cout << " Breaks:" << D.TargetPkg().Name();
+           cout << " Breaks:" << D.TargetPkg().FullName(false);
         else
-           cout << " Depends:" << D.TargetPkg().Name();
+           cout << " Depends:" << D.TargetPkg().FullName(false);
       }            
       cout << endl;
 
-      _error->Error("Conf Broken %s",Pkg.Name());
+      _error->Error("Conf Broken %s",Pkg.FullName(false).c_str());
    }   
    else
    {
@@ -181,10 +189,16 @@ bool pkgSimulate::Configure(PkgIterator iPkg)
 bool pkgSimulate::Remove(PkgIterator iPkg,bool Purge)
 {
    // Adapt the iterator
-   PkgIterator Pkg = Sim.FindPkg(iPkg.Name());
+   PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
+   if (Pkg.end() == true)
+   {
+      std::cerr << (Purge ? "Purg" : "Remv") << " invalid package " << iPkg.FullName() << std::endl;
+      return false;
+   }
 
    Flags[Pkg->ID] = 3;
    Sim.MarkDelete(Pkg);
+
    if (Purge == true)
       cout << "Purg ";
    else
@@ -205,12 +219,12 @@ bool pkgSimulate::Remove(PkgIterator iPkg,bool Purge)
 void pkgSimulate::ShortBreaks()
 {
    cout << " [";
-   for (PkgIterator I = Sim.PkgBegin(); I.end() == false; I++)
+   for (PkgIterator I = Sim.PkgBegin(); I.end() == false; ++I)
    {
       if (Sim[I].InstBroken() == true)
       {
         if (Flags[I->ID] == 0)
-           cout << I.Name() << ' ';
+           cout << I.FullName(false) << ' ';
 /*      else
            cout << I.Name() << "! ";*/
       }      
@@ -227,7 +241,7 @@ bool pkgApplyStatus(pkgDepCache &Cache)
 {
    pkgDepCache::ActionGroup group(Cache);
 
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
       if (I->VersionList == 0)
         continue;
@@ -246,7 +260,7 @@ bool pkgApplyStatus(pkgDepCache &Cache)
               Cache.MarkInstall(I, false, 0, false);
            else
               return _error->Error(_("The package %s needs to be reinstalled, "
-                                   "but I can't find an archive for it."),I.Name());
+                                   "but I can't find an archive for it."),I.FullName(true).c_str());
         }
         
         continue;
@@ -269,19 +283,19 @@ bool pkgApplyStatus(pkgDepCache &Cache)
                 Cache[I].CandidateVerIter(Cache).Downloadable() == true)
               Cache.MarkInstall(I, true, 0, false);
            else
-              Cache.MarkDelete(I);
+              Cache.MarkDelete(I, false, 0, false);
         }
         break;
 
         // This means removal failed
         case pkgCache::State::HalfInstalled:
-        Cache.MarkDelete(I);
+        Cache.MarkDelete(I, false, 0, false);
         break;
         
         default:
         if (I->InstState != pkgCache::State::Ok)
            return _error->Error("The package %s is not ok and I "
-                                "don't know how to fix it!",I.Name());
+                                "don't know how to fix it!",I.FullName(false).c_str());
       }
    }
    return true;
@@ -296,13 +310,13 @@ bool pkgFixBroken(pkgDepCache &Cache)
    pkgDepCache::ActionGroup group(Cache);
 
    // Auto upgrade all broken packages
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
       if (Cache[I].NowBroken() == true)
         Cache.MarkInstall(I, true, 0, false);
    
    /* Fix packages that are in a NeedArchive state but don't have a
       downloadable install version */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
       if (I.State() != pkgCache::PkgIterator::NeedsUnpack ||
          Cache[I].Delete() == true)
@@ -318,138 +332,14 @@ bool pkgFixBroken(pkgDepCache &Cache)
    return Fix.Resolve(true);
 }
                                                                        /*}}}*/
-// DistUpgrade - Distribution upgrade                                  /*{{{*/
-// ---------------------------------------------------------------------
-/* This autoinstalls every package and then force installs every 
-   pre-existing package. This creates the initial set of conditions which 
-   most likely contain problems because too many things were installed.
-   
-   The problem resolver is used to resolve the problems.
- */
-bool pkgDistUpgrade(pkgDepCache &Cache)
-{
-   pkgDepCache::ActionGroup group(Cache);
-
-   /* Auto upgrade all installed packages, this provides the basis 
-      for the installation */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-      if (I->CurrentVer != 0)
-        Cache.MarkInstall(I, true, 0, false);
-
-   /* Now, auto upgrade all essential packages - this ensures that
-      the essential packages are present and working */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-      if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
-        Cache.MarkInstall(I, true, 0, false);
-   
-   /* We do it again over all previously installed packages to force 
-      conflict resolution on them all. */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-      if (I->CurrentVer != 0)
-        Cache.MarkInstall(I, false, 0, false);
-
-   pkgProblemResolver Fix(&Cache);
-
-   // Hold back held packages.
-   if (_config->FindB("APT::Ignore-Hold",false) == false)
-   {
-      for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-      {
-        if (I->SelectedState == pkgCache::State::Hold)
-        {
-           Fix.Protect(I);
-           Cache.MarkKeep(I, false, false);
-        }
-      }
-   }
-   
-   return Fix.Resolve();
-}
-                                                                       /*}}}*/
-// AllUpgrade - Upgrade as many packages as possible                   /*{{{*/
-// ---------------------------------------------------------------------
-/* Right now the system must be consistent before this can be called.
-   It also will not change packages marked for install, it only tries
-   to install packages not marked for install */
-bool pkgAllUpgrade(pkgDepCache &Cache)
-{
-   pkgDepCache::ActionGroup group(Cache);
-
-   pkgProblemResolver Fix(&Cache);
-
-   if (Cache.BrokenCount() != 0)
-      return false;
-   
-   // Upgrade all installed packages
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-   {
-      if (Cache[I].Install() == true)
-        Fix.Protect(I);
-         
-      if (_config->FindB("APT::Ignore-Hold",false) == false)
-        if (I->SelectedState == pkgCache::State::Hold)
-           continue;
-      
-      if (I->CurrentVer != 0 && Cache[I].InstallVer != 0)
-        Cache.MarkInstall(I, false, 0, false);
-   }
-      
-   return Fix.ResolveByKeep();
-}
-                                                                       /*}}}*/
-// MinimizeUpgrade - Minimizes the set of packages to be upgraded      /*{{{*/
-// ---------------------------------------------------------------------
-/* This simply goes over the entire set of packages and tries to keep 
-   each package marked for upgrade. If a conflict is generated then 
-   the package is restored. */
-bool pkgMinimizeUpgrade(pkgDepCache &Cache)
-{   
-   pkgDepCache::ActionGroup group(Cache);
-
-   if (Cache.BrokenCount() != 0)
-      return false;
-   
-   // We loop for 10 tries to get the minimal set size.
-   bool Change = false;
-   unsigned int Count = 0;
-   do
-   {
-      Change = false;
-      for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-      {
-        // Not interesting
-        if (Cache[I].Upgrade() == false || Cache[I].NewInstall() == true)
-           continue;
-
-        // Keep it and see if that is OK
-        Cache.MarkKeep(I, false, false);
-        if (Cache.BrokenCount() != 0)
-           Cache.MarkInstall(I, false, 0, false);
-        else
-        {
-           // If keep didnt actually do anything then there was no change..
-           if (Cache[I].Upgrade() == false)
-              Change = true;
-        }       
-      }      
-      Count++;
-   }
-   while (Change == true && Count < 10);
-
-   if (Cache.BrokenCount() != 0)
-      return _error->Error("Internal Error in pkgMinimizeUpgrade");
-   
-   return true;
-}
-                                                                       /*}}}*/
 // ProblemResolver::pkgProblemResolver - Constructor                   /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-pkgProblemResolver::pkgProblemResolver(pkgDepCache *pCache) : Cache(*pCache)
+pkgProblemResolver::pkgProblemResolver(pkgDepCache *pCache) : d(NULL), Cache(*pCache)
 {
    // Allocate memory
    unsigned long Size = Cache.Head().PackageCount;
-   Scores = new signed short[Size];
+   Scores = new int[Size];
    Flags = new unsigned char[Size];
    memset(Flags,0,sizeof(*Flags)*Size);
    
@@ -469,13 +359,11 @@ pkgProblemResolver::~pkgProblemResolver()
 // ProblemResolver::ScoreSort - Sort the list by score                 /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-int pkgProblemResolver::ScoreSort(const void *a,const void *b)
+int pkgProblemResolver::ScoreSort(Package const *A,Package const *B)
 {
-   Package const **A = (Package const **)a;
-   Package const **B = (Package const **)b;
-   if (This->Scores[(*A)->ID] > This->Scores[(*B)->ID])
+   if (Scores[A->ID] > Scores[B->ID])
       return -1;
-   if (This->Scores[(*A)->ID] < This->Scores[(*B)->ID])
+   if (Scores[A->ID] < Scores[B->ID])
       return 1;
    return 0;
 }
@@ -488,92 +376,113 @@ void pkgProblemResolver::MakeScores()
    unsigned long Size = Cache.Head().PackageCount;
    memset(Scores,0,sizeof(*Scores)*Size);
 
-   // Important Required Standard Optional Extra
-   signed short PrioMap[] = {
+   // maps to pkgCache::State::VerPriority: 
+   //    Required Important Standard Optional Extra
+   int PrioMap[] = {
       0,
-      _config->FindI("pkgProblemResolver::Scores::Important",3),
-      _config->FindI("pkgProblemResolver::Scores::Required",2),
+      _config->FindI("pkgProblemResolver::Scores::Required",3),
+      _config->FindI("pkgProblemResolver::Scores::Important",2),
       _config->FindI("pkgProblemResolver::Scores::Standard",1),
       _config->FindI("pkgProblemResolver::Scores::Optional",-1),
       _config->FindI("pkgProblemResolver::Scores::Extra",-2)
    };
-   signed short PrioEssentials = _config->FindI("pkgProblemResolver::Scores::Essentials",100);
-   signed short PrioInstalledAndNotObsolete = _config->FindI("pkgProblemResolver::Scores::NotObsolete",1);
-   signed short PrioDepends = _config->FindI("pkgProblemResolver::Scores::Depends",1);
-   signed short PrioRecommends = _config->FindI("pkgProblemResolver::Scores::Recommends",1);
-   signed short AddProtected = _config->FindI("pkgProblemResolver::Scores::AddProtected",10000);
-   signed short AddEssential = _config->FindI("pkgProblemResolver::Scores::AddEssential",5000);
+   int PrioEssentials = _config->FindI("pkgProblemResolver::Scores::Essentials",100);
+   int PrioInstalledAndNotObsolete = _config->FindI("pkgProblemResolver::Scores::NotObsolete",1);
+   int DepMap[] = {
+      0,
+      _config->FindI("pkgProblemResolver::Scores::Depends",1),
+      _config->FindI("pkgProblemResolver::Scores::PreDepends",1),
+      _config->FindI("pkgProblemResolver::Scores::Suggests",0),
+      _config->FindI("pkgProblemResolver::Scores::Recommends",1),
+      _config->FindI("pkgProblemResolver::Scores::Conflicts",-1),
+      _config->FindI("pkgProblemResolver::Scores::Replaces",0),
+      _config->FindI("pkgProblemResolver::Scores::Obsoletes",0),
+      _config->FindI("pkgProblemResolver::Scores::Breaks",-1),
+      _config->FindI("pkgProblemResolver::Scores::Enhances",0)
+   };
+   int AddProtected = _config->FindI("pkgProblemResolver::Scores::AddProtected",10000);
+   int AddEssential = _config->FindI("pkgProblemResolver::Scores::AddEssential",5000);
 
    if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true)
       clog << "Settings used to calculate pkgProblemResolver::Scores::" << endl
-         << "  Important => " << PrioMap[1] << endl
-         << "  Required => " << PrioMap[2] << endl
-         << "  Standard => " << PrioMap[3] << endl
-         << "  Optional => " << PrioMap[4] << endl
-         << "  Extra => " << PrioMap[5] << endl
+         << "  Required => " << PrioMap[pkgCache::State::Required] << endl
+         << "  Important => " << PrioMap[pkgCache::State::Important] << endl
+         << "  Standard => " << PrioMap[pkgCache::State::Standard] << endl
+         << "  Optional => " << PrioMap[pkgCache::State::Optional] << endl
+         << "  Extra => " << PrioMap[pkgCache::State::Extra] << endl
          << "  Essentials => " << PrioEssentials << endl
          << "  InstalledAndNotObsolete => " << PrioInstalledAndNotObsolete << endl
-         << "  Depends => " << PrioDepends << endl
-         << "  Recommends => " << PrioRecommends << endl
+         << "  Pre-Depends => " << DepMap[pkgCache::Dep::PreDepends] << endl
+         << "  Depends => " << DepMap[pkgCache::Dep::Depends] << endl
+         << "  Recommends => " << DepMap[pkgCache::Dep::Recommends] << endl
+         << "  Suggests => " << DepMap[pkgCache::Dep::Suggests] << endl
+         << "  Conflicts => " << DepMap[pkgCache::Dep::Conflicts] << endl
+         << "  Breaks => " << DepMap[pkgCache::Dep::DpkgBreaks] << endl
+         << "  Replaces => " << DepMap[pkgCache::Dep::Replaces] << endl
+         << "  Obsoletes => " << DepMap[pkgCache::Dep::Obsoletes] << endl
+         << "  Enhances => " << DepMap[pkgCache::Dep::Enhances] << endl
          << "  AddProtected => " << AddProtected << endl
          << "  AddEssential => " << AddEssential << endl;
 
    // Generate the base scores for a package based on its properties
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
       if (Cache[I].InstallVer == 0)
         continue;
       
-      signed short &Score = Scores[I->ID];
+      int &Score = Scores[I->ID];
       
       /* This is arbitrary, it should be high enough to elevate an
          essantial package above most other packages but low enough
         to allow an obsolete essential packages to be removed by
-        a conflicts on a powerfull normal package (ie libc6) */
-      if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
+        a conflicts on a powerful normal package (ie libc6) */
+      if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential
+         || (I->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important)
         Score += PrioEssentials;
 
-      // We transform the priority
-      if (Cache[I].InstVerIter(Cache)->Priority <= 5)
-        Score += PrioMap[Cache[I].InstVerIter(Cache)->Priority];
-      
+      pkgCache::VerIterator const InstVer = Cache[I].InstVerIter(Cache);
+      // We apply priorities only to downloadable packages, all others are prio:extra
+      // as an obsolete prio:standard package can't be that standard anymore…
+      if (InstVer->Priority <= pkgCache::State::Extra && InstVer.Downloadable() == true)
+        Score += PrioMap[InstVer->Priority];
+      else
+        Score += PrioMap[pkgCache::State::Extra];
+
       /* This helps to fix oddball problems with conflicting packages
-         on the same level. We enhance the score of installed packages 
-        if those are not obsolete
-      */
+        on the same level. We enhance the score of installed packages
+        if those are not obsolete */
       if (I->CurrentVer != 0 && Cache[I].CandidateVer != 0 && Cache[I].CandidateVerIter(Cache).Downloadable())
         Score += PrioInstalledAndNotObsolete;
-   }
 
-   // Now that we have the base scores we go and propogate dependencies
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
-   {
-      if (Cache[I].InstallVer == 0)
-        continue;
-      
-      for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList(); D.end() == false; D++)
+      // propagate score points along dependencies
+      for (pkgCache::DepIterator D = InstVer.DependsList(); D.end() == false; ++D)
       {
-        if (D->Type == pkgCache::Dep::Depends || 
-            D->Type == pkgCache::Dep::PreDepends)
-           Scores[D.TargetPkg()->ID] += PrioDepends;
-        else if (D->Type == pkgCache::Dep::Recommends)
-           Scores[D.TargetPkg()->ID] += PrioRecommends;
+        if (DepMap[D->Type] == 0)
+           continue;
+        pkgCache::PkgIterator const T = D.TargetPkg();
+        if (D->Version != 0)
+        {
+           pkgCache::VerIterator const IV = Cache[T].InstVerIter(Cache);
+           if (IV.end() == true || D.IsSatisfied(IV) == false)
+              continue;
+        }
+        Scores[T->ID] += DepMap[D->Type];
       }
-   }   
-   
+   }
+
    // Copy the scores to advoid additive looping
-   SPtrArray<signed short> OldScores = new signed short[Size];
-   memcpy(OldScores,Scores,sizeof(*Scores)*Size);
+   std::unique_ptr<int[]> OldScores(new int[Size]);
+   memcpy(OldScores.get(),Scores,sizeof(*Scores)*Size);
       
    /* Now we cause 1 level of dependency inheritance, that is we add the 
       score of the packages that depend on the target Package. This 
       fortifies high scoring packages */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
       if (Cache[I].InstallVer == 0)
         continue;
       
-      for (pkgCache::DepIterator D = I.RevDependsList(); D.end() == false; D++)
+      for (pkgCache::DepIterator D = I.RevDependsList(); D.end() == false; ++D)
       {
         // Only do it for the install version
         if ((pkgCache::Version *)D.ParentVer() != Cache[D.ParentPkg()].InstallVer ||
@@ -582,15 +491,18 @@ void pkgProblemResolver::MakeScores()
              D->Type != pkgCache::Dep::Recommends))
            continue;    
         
-        Scores[I->ID] += abs(OldScores[D.ParentPkg()->ID]);
+        // Do not propagate negative scores otherwise
+        // an extra (-2) package might score better than an optional (-1)
+        if (OldScores[D.ParentPkg()->ID] > 0)
+            Scores[I->ID] += OldScores[D.ParentPkg()->ID];
       }      
    }
 
-   /* Now we propogate along provides. This makes the packages that 
+   /* Now we propagate along provides. This makes the packages that
       provide important packages extremely important */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
-      for (pkgCache::PrvIterator P = I.ProvidesList(); P.end() == false; P++)
+      for (pkgCache::PrvIterator P = I.ProvidesList(); P.end() == false; ++P)
       {
         // Only do it once per package
         if ((pkgCache::Version *)P.OwnerVer() != Cache[P.OwnerPkg()].InstallVer)
@@ -601,11 +513,12 @@ void pkgProblemResolver::MakeScores()
 
    /* Protected things are pushed really high up. This number should put them
       ahead of everything */
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
       if ((Flags[I->ID] & Protected) != 0)
         Scores[I->ID] += AddProtected;
-      if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
+      if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential ||
+          (I->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important)
         Scores[I->ID] += AddEssential;
    }
 }
@@ -639,12 +552,10 @@ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
       // Compute a single dependency element (glob or)
       pkgCache::DepIterator Start = D;
       pkgCache::DepIterator End = D;
-      unsigned char State = 0;
       for (bool LastOR = true; D.end() == false && LastOR == true;)
       {
-        State |= Cache[D];
         LastOR = (D->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or;
-        D++;
+        ++D;
         if (LastOR == true)
            End = D;
       }
@@ -665,7 +576,7 @@ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
         if ((Flags[P->ID] & Protected) == Protected)
         {
            if (Debug == true)
-              clog << "    Reinst Failed because of protected " << P.Name() << endl;
+              clog << "    Reinst Failed because of protected " << P.FullName(false) << endl;
            Fail = true;
         }      
         else
@@ -676,7 +587,7 @@ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
               if (DoUpgrade(P) == false)
               {
                  if (Debug == true)
-                    clog << "    Reinst Failed because of " << P.Name() << endl;
+                    clog << "    Reinst Failed because of " << P.FullName(false) << endl;
                  Fail = true;
               }
               else
@@ -689,20 +600,18 @@ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
            {
               /* We let the algorithm deal with conflicts on its next iteration,
                it is much smarter than us */
-              if (Start->Type == pkgCache::Dep::Conflicts || 
-                  Start->Type == pkgCache::Dep::DpkgBreaks || 
-                  Start->Type == pkgCache::Dep::Obsoletes)
+              if (Start.IsNegative() == true)
                   break;
               
               if (Debug == true)
-                 clog << "    Reinst Failed early because of " << Start.TargetPkg().Name() << endl;
+                 clog << "    Reinst Failed early because of " << Start.TargetPkg().FullName(false) << endl;
               Fail = true;
            }     
         }
         
         if (Start == End)
            break;
-        Start++;
+        ++Start;
       }
       if (Fail == true)
         break;
@@ -714,16 +623,25 @@ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
       if (WasKept == true)
         Cache.MarkKeep(Pkg, false, false);
       else
-        Cache.MarkDelete(Pkg);
+        Cache.MarkDelete(Pkg, false, 0, false);
       return false;
    }    
    
    if (Debug == true)
-      clog << "  Re-Instated " << Pkg.Name() << endl;
+      clog << "  Re-Instated " << Pkg.FullName(false) << endl;
    return true;
 }
                                                                        /*}}}*/
-// ProblemResolver::Resolve - Run the resolution pass                  /*{{{*/
+// ProblemResolver::Resolve - calls a resolver to fix the situation    /*{{{*/
+bool pkgProblemResolver::Resolve(bool BrokenFix, OpProgress * const Progress)
+{
+   std::string const solver = _config->Find("APT::Solver", "internal");
+   if (solver != "internal")
+      return EDSP::ResolveExternal(solver.c_str(), Cache, false, false, false, Progress);
+   return ResolveInternal(BrokenFix);
+}
+                                                                       /*}}}*/
+// ProblemResolver::ResolveInternal - Run the resolution pass          /*{{{*/
 // ---------------------------------------------------------------------
 /* This routines works by calculating a score for each package. The score
    is derived by considering the package's priority and all reverse 
@@ -731,24 +649,22 @@ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
    adjusting the package will inflict. 
       
    It goes from highest score to lowest and corrects all of the breaks by 
-   keeping or removing the dependant packages. If that fails then it removes
+   keeping or removing the dependent packages. If that fails then it removes
    the package itself and goes on. The routine should be able to intelligently
    go from any broken state to a fixed state. 
  
    The BrokenFix flag enables a mode where the algorithm tries to 
    upgrade packages to advoid problems. */
-bool pkgProblemResolver::Resolve(bool BrokenFix)
+bool pkgProblemResolver::ResolveInternal(bool const BrokenFix)
 {
    pkgDepCache::ActionGroup group(Cache);
 
-   unsigned long Size = Cache.Head().PackageCount;
-
    // Record which packages are marked for install
    bool Again = false;
    do
    {
       Again = false;
-      for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+      for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
       {
         if (Cache[I].Install() == true)
            Flags[I->ID] |= PreInstalled;
@@ -768,45 +684,53 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
    }
    while (Again == true);
 
-   if (Debug == true)
-      clog << "Starting" << endl;
+   if (Debug == true) {
+      clog << "Starting pkgProblemResolver with broken count: " 
+           << Cache.BrokenCount() << endl;
+   }
    
    MakeScores();
-   
+
+   unsigned long const Size = Cache.Head().PackageCount;
+
    /* We have to order the packages so that the broken fixing pass 
       operates from highest score to lowest. This prevents problems when
       high score packages cause the removal of lower score packages that
       would cause the removal of even lower score packages. */
-   SPtrArray<pkgCache::Package *> PList = new pkgCache::Package *[Size];
-   pkgCache::Package **PEnd = PList;
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   std::unique_ptr<pkgCache::Package *[]> PList(new pkgCache::Package *[Size]);
+   pkgCache::Package **PEnd = PList.get();
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
       *PEnd++ = I;
-   This = this;
-   qsort(PList,PEnd - PList,sizeof(*PList),&ScoreSort);
+
+   std::sort(PList.get(), PEnd, [this](Package *a, Package *b) { return ScoreSort(a, b) < 0; });
 
    if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true)
    {
       clog << "Show Scores" << endl;
-      for (pkgCache::Package **K = PList; K != PEnd; K++)
+      for (pkgCache::Package **K = PList.get(); K != PEnd; K++)
          if (Scores[(*K)->ID] != 0)
          {
            pkgCache::PkgIterator Pkg(Cache,*K);
-           clog << Scores[(*K)->ID] << ' ' << Pkg << std::endl;
+           clog << Scores[(*K)->ID] << ' ' << APT::PrettyPkg(&Cache, Pkg) << std::endl;
          }
    }
 
-   if (Debug == true)
-      clog << "Starting 2" << endl;
+   if (Debug == true) {
+      clog << "Starting 2 pkgProblemResolver with broken count: " 
+           << Cache.BrokenCount() << endl;
+   }
 
    /* Now consider all broken packages. For each broken package we either
       remove the package or fix it's problem. We do this once, it should
       not be possible for a loop to form (that is a < b < c and fixing b by
       changing a breaks c) */
    bool Change = true;
+   bool const TryFixByInstall = _config->FindB("pkgProblemResolver::FixByInstall", true);
+   std::vector<PackageKill> KillList;
    for (int Counter = 0; Counter != 10 && Change == true; Counter++)
    {
       Change = false;
-      for (pkgCache::Package **K = PList; K != PEnd; K++)
+      for (pkgCache::Package **K = PList.get(); K != PEnd; K++)
       {
         pkgCache::PkgIterator I(Cache,*K);
 
@@ -819,7 +743,7 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
             (Flags[I->ID] & ReInstateTried) == 0)
         {
            if (Debug == true)
-              clog << " Try to Re-Instate " << I.Name() << endl;
+              clog << " Try to Re-Instate (" << Counter << ") " << I.FullName(false) << endl;
            unsigned long OldBreaks = Cache.BrokenCount();
            pkgCache::Version *OldVer = Cache[I].InstallVer;
            Flags[I->ID] &= ReInstateTried;
@@ -829,28 +753,28 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
                OldBreaks < Cache.BrokenCount())
            {
               if (OldVer == 0)
-                 Cache.MarkDelete(I);
+                 Cache.MarkDelete(I, false, 0, false);
               else
                  Cache.MarkKeep(I, false, false);
            }       
            else
               if (Debug == true)
-                 clog << "Re-Instated " << I.Name() << " (" << OldBreaks << " vs " << Cache.BrokenCount() << ')' << endl;
+                 clog << "Re-Instated " << I.FullName(false) << " (" << OldBreaks << " vs " << Cache.BrokenCount() << ')' << endl;
         }
            
         if (Cache[I].InstallVer == 0 || Cache[I].InstBroken() == false)
            continue;
         
         if (Debug == true)
-           clog << "Investigating " << I.Name() << endl;
+           clog << "Investigating (" << Counter << ") " << APT::PrettyPkg(&Cache, I) << endl;
         
         // Isolate the problem dependency
-        PackageKill KillList[100];
-        PackageKill *LEnd = KillList;
         bool InOr = false;
         pkgCache::DepIterator Start;
         pkgCache::DepIterator End;
-        PackageKill *OldEnd = LEnd;
+        size_t OldSize = 0;
+
+        KillList.resize(0);
         
         enum {OrRemove,OrKeep} OrOp = OrRemove;
         for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList();
@@ -860,22 +784,22 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
            if (Start == End)
            {
               // Decide what to do
-              if (InOr == true)
+              if (InOr == true && OldSize == KillList.size())
               {
-                 if (OldEnd == LEnd && OrOp == OrRemove)
+                 if (OrOp == OrRemove)
                  {
                     if ((Flags[I->ID] & Protected) != Protected)
                     {
                        if (Debug == true)
-                          clog << "  Or group remove for " << I.Name() << endl;
-                       Cache.MarkDelete(I);
+                          clog << "  Or group remove for " << I.FullName(false) << endl;
+                       Cache.MarkDelete(I, false, 0, false);
                        Change = true;
-                    }               
-                 }               
-                 if (OldEnd == LEnd && OrOp == OrKeep)
+                    }
+                 }
+                 else if (OrOp == OrKeep)
                  {
                     if (Debug == true)
-                       clog << "  Or group keep for " << I.Name() << endl;
+                       clog << "  Or group keep for " << I.FullName(false) << endl;
                     Cache.MarkKeep(I, false, false);
                     Change = true;
                  }
@@ -894,11 +818,11 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
                  continue;
 
               InOr = Start != End;
-              OldEnd = LEnd;
+              OldSize = KillList.size();
            }
            else
             {
-              Start++;
+              ++Start;
               // We only worry about critical deps.
               if (Start.IsCritical() != true)
                   continue;
@@ -912,16 +836,14 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
            }
            
            if (Debug == true)
-              clog << "Package " << I.Name() << " has broken " << Start.DepType() << " on " << Start.TargetPkg().Name() << endl;
+              clog << "Broken " << APT::PrettyDep(&Cache, Start) << endl;
 
            /* Look across the version list. If there are no possible
               targets then we keep the package and bail. This is necessary
-              if a package has a dep on another package that cant be found */
-           SPtrArray<pkgCache::Version *> VList = Start.AllTargets();
-           if (*VList == 0 && (Flags[I->ID] & Protected) != Protected &&
-               Start->Type != pkgCache::Dep::Conflicts &&
-               Start->Type != pkgCache::Dep::DpkgBreaks &&
-               Start->Type != pkgCache::Dep::Obsoletes &&
+              if a package has a dep on another package that can't be found */
+           std::unique_ptr<pkgCache::Version *[]> VList(Start.AllTargets());
+           if (VList[0] == 0 && (Flags[I->ID] & Protected) != Protected &&
+               Start.IsNegative() == false &&
                Cache[I].NowBroken() == false)
            {          
               if (InOr == true)
@@ -937,22 +859,34 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
            }
            
            bool Done = false;
-           for (pkgCache::Version **V = VList; *V != 0; V++)
+           for (pkgCache::Version **V = VList.get(); *V != 0; V++)
            {
               pkgCache::VerIterator Ver(Cache,*V);
               pkgCache::PkgIterator Pkg = Ver.ParentPkg();
 
+               /* This is a conflicts, and the version we are looking
+                  at is not the currently selected version of the 
+                  package, which means it is not necessary to 
+                  remove/keep */
+               if (Cache[Pkg].InstallVer != Ver && Start.IsNegative() == true)
+               {
+                  if (Debug) 
+                     clog << "  Conflicts//Breaks against version " 
+                          << Ver.VerStr() << " for " << Pkg.Name() 
+                          << " but that is not InstVer, ignoring"
+                          << endl;
+                  continue;
+               }
+
               if (Debug == true)
-                 clog << "  Considering " << Pkg.Name() << ' ' << (int)Scores[Pkg->ID] <<
-                 " as a solution to " << I.Name() << ' ' << (int)Scores[I->ID] << endl;
+                 clog << "  Considering " << Pkg.FullName(false) << ' ' << Scores[Pkg->ID] <<
+                 " as a solution to " << I.FullName(false) << ' ' << Scores[I->ID] << endl;
 
               /* Try to fix the package under consideration rather than
                  fiddle with the VList package */
               if (Scores[I->ID] <= Scores[Pkg->ID] ||
                   ((Cache[Start] & pkgDepCache::DepNow) == 0 &&
-                   End->Type != pkgCache::Dep::Conflicts &&
-                   End->Type != pkgCache::Dep::DpkgBreaks &&
-                   End->Type != pkgCache::Dep::Obsoletes))
+                   End.IsNegative() == false))
               {
                  // Try a little harder to fix protected packages..
                  if ((Flags[I->ID] & Protected) == Protected)
@@ -982,21 +916,40 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
                        Cache.MarkInstall(I, false, 0, false);
                     
                     if (Debug == true)
-                       clog << "  Holding Back " << I.Name() << " rather than change " << Start.TargetPkg().Name() << endl;
+                       clog << "  Holding Back " << I.FullName(false) << " rather than change " << Start.TargetPkg().FullName(false) << endl;
                  }               
                  else
                  {                  
                     if (BrokenFix == false || DoUpgrade(I) == false)
                     {
                        // Consider other options
-                       if (InOr == false)
+                       if (InOr == false || Cache[I].Garbage == true)
                        {
                           if (Debug == true)
-                             clog << "  Removing " << I.Name() << " rather than change " << Start.TargetPkg().Name() << endl;
-                          Cache.MarkDelete(I);
+                             clog << "  Removing " << I.FullName(false) << " rather than change " << Start.TargetPkg().FullName(false) << endl;
+                          Cache.MarkDelete(I, false, 0, false);
                           if (Counter > 1 && Scores[Pkg->ID] > Scores[I->ID])
                              Scores[I->ID] = Scores[Pkg->ID];
                        }
+                       else if (TryFixByInstall == true &&
+                                Start.TargetPkg()->CurrentVer == 0 &&
+                                Cache[Start.TargetPkg()].Delete() == false &&
+                                (Flags[Start.TargetPkg()->ID] & ToRemove) != ToRemove &&
+                                Cache.GetCandidateVersion(Start.TargetPkg()).end() == false)
+                       {
+                          /* Before removing or keeping the package with the broken dependency
+                             try instead to install the first not previously installed package
+                             solving this dependency. This helps every time a previous solver
+                             is removed by the resolver because of a conflict or alike but it is
+                             dangerous as it could trigger new breaks/conflicts… */
+                          if (Debug == true)
+                             clog << "  Try Installing " << APT::PrettyPkg(&Cache, Start.TargetPkg()) << " before changing " << I.FullName(false) << std::endl;
+                          unsigned long const OldBroken = Cache.BrokenCount();
+                          Cache.MarkInstall(Start.TargetPkg(), true, 1, false);
+                          // FIXME: we should undo the complete MarkInstall process here
+                          if (Cache[Start.TargetPkg()].InstBroken() == true || Cache.BrokenCount() > OldBroken)
+                             Cache.MarkDelete(Start.TargetPkg(), false, 1, false);
+                       }
                     }
                  }
                                  
@@ -1006,25 +959,17 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
               }
               else
               {
-                 /* This is a conflicts, and the version we are looking
-                    at is not the currently selected version of the 
-                    package, which means it is not necessary to 
-                    remove/keep */
-                 if (Cache[Pkg].InstallVer != Ver &&
-                     (Start->Type == pkgCache::Dep::Conflicts ||
-                      Start->Type == pkgCache::Dep::Obsoletes))
-                    continue;
-
                  if (Start->Type == pkgCache::Dep::DpkgBreaks)
                  {
                     // first, try upgradring the package, if that
                     // does not help, the breaks goes onto the
                     // kill list
+                     //
                     // FIXME: use DoUpgrade(Pkg) instead?
-                    if (Cache[End] & pkgDepCache::DepGCVer) 
+                    if (Cache[End] & pkgDepCache::DepGCVer)
                     {
                        if (Debug)
-                          clog << "  Upgrading " << Pkg.Name() << " due to Breaks field in " << I.Name() << endl;
+                          clog << "  Upgrading " << Pkg.FullName(false) << " due to Breaks field in " << I.FullName(false) << endl;
                        Cache.MarkInstall(Pkg, false, 0, false);
                        continue;
                     }
@@ -1035,23 +980,18 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
                     continue;
                
                  if (Debug == true)
-                    clog << "  Added " << Pkg.Name() << " to the remove list" << endl;
-                 
-                 LEnd->Pkg = Pkg;
-                 LEnd->Dep = End;
-                 LEnd++;
+                    clog << "  Added " << Pkg.FullName(false) << " to the remove list" << endl;
+
+                 KillList.push_back({Pkg, End});
                  
-                 if (Start->Type != pkgCache::Dep::Conflicts &&
-                     Start->Type != pkgCache::Dep::Obsoletes)
+                 if (Start.IsNegative() == false)
                     break;
               }
            }
 
            // Hm, nothing can possibly satisify this dep. Nuke it.
-           if (VList[0] == 0 && 
-               Start->Type != pkgCache::Dep::Conflicts &&
-               Start->Type != pkgCache::Dep::DpkgBreaks &&
-               Start->Type != pkgCache::Dep::Obsoletes &&
+           if (VList[0] == 0 &&
+               Start.IsNegative() == false &&
                (Flags[I->ID] & Protected) != Protected)
            {
               bool Installed = Cache[I].Install();
@@ -1067,14 +1007,14 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
                     Cache.MarkInstall(I, false, 0, false);
                  
                  if (Debug == true)
-                    clog << "  Holding Back " << I.Name() << " because I can't find " << Start.TargetPkg().Name() << endl;
+                    clog << "  Holding Back " << I.FullName(false) << " because I can't find " << Start.TargetPkg().FullName(false) << endl;
               }               
               else
               {
                  if (Debug == true)
-                    clog << "  Removing " << I.Name() << " because I can't find " << Start.TargetPkg().Name() << endl;
+                    clog << "  Removing " << I.FullName(false) << " because I can't find " << Start.TargetPkg().FullName(false) << endl;
                  if (InOr == false)
-                    Cache.MarkDelete(I);
+                    Cache.MarkDelete(I, false, 0, false);
               }
 
               Change = true;
@@ -1092,24 +1032,22 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
         // Apply the kill list now
         if (Cache[I].InstallVer != 0)
         {
-           for (PackageKill *J = KillList; J != LEnd; J++)
+           for (auto J = KillList.begin(); J != KillList.end(); J++)
            {
               Change = true;
               if ((Cache[J->Dep] & pkgDepCache::DepGNow) == 0)
               {
-                 if (J->Dep->Type == pkgCache::Dep::Conflicts || 
-                     J->Dep->Type == pkgCache::Dep::DpkgBreaks ||
-                     J->Dep->Type == pkgCache::Dep::Obsoletes)
+                 if (J->Dep.IsNegative() == true)
                  {
                     if (Debug == true)
-                       clog << "  Fixing " << I.Name() << " via remove of " << J->Pkg.Name() << endl;
-                    Cache.MarkDelete(J->Pkg);
+                       clog << "  Fixing " << I.FullName(false) << " via remove of " << J->Pkg.FullName(false) << endl;
+                    Cache.MarkDelete(J->Pkg, false, 0, false);
                  }
               }
               else
               {
                  if (Debug == true)
-                    clog << "  Fixing " << I.Name() << " via keep of " << J->Pkg.Name() << endl;
+                    clog << "  Fixing " << I.FullName(false) << " via keep of " << J->Pkg.FullName(false) << endl;
                  Cache.MarkKeep(J->Pkg, false, false);
               }
 
@@ -1130,7 +1068,7 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
    {
       // See if this is the result of a hold
       pkgCache::PkgIterator I = Cache.PkgBegin();
-      for (;I.end() != true; I++)
+      for (;I.end() != true; ++I)
       {
         if (Cache[I].InstBroken() == false)
            continue;
@@ -1142,10 +1080,10 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
    
    // set the auto-flags (mvo: I'm not sure if we _really_ need this)
    pkgCache::PkgIterator I = Cache.PkgBegin();
-   for (;I.end() != true; I++) {
+   for (;I.end() != true; ++I) {
       if (Cache[I].NewInstall() && !(Flags[I->ID] & PreInstalled)) {
         if(_config->FindI("Debug::pkgAutoRemove",false)) {
-           std::clog << "Resolve installed new pkg: " << I.Name(
+           std::clog << "Resolve installed new pkg: " << I.FullName(false
                      << " (now marking it as auto)" << std::endl;
         }
         Cache[I].Flags |= pkgCache::Flag::Auto;
@@ -1156,12 +1094,56 @@ bool pkgProblemResolver::Resolve(bool BrokenFix)
    return true;
 }
                                                                        /*}}}*/
+// ProblemResolver::BreaksInstOrPolicy - Check if the given pkg is broken/*{{{*/
+// ---------------------------------------------------------------------
+/* This checks if the given package is broken either by a hard dependency
+   (InstBroken()) or by introducing a new policy breakage e.g. new
+   unsatisfied recommends for a package that was in "policy-good" state
+
+   Note that this is not perfect as it will ignore further breakage
+   for already broken policy (recommends)
+*/
+bool pkgProblemResolver::InstOrNewPolicyBroken(pkgCache::PkgIterator I)
+{
+   // a broken install is always a problem
+   if (Cache[I].InstBroken() == true)
+   {
+      if (Debug == true)
+        std::clog << "  Dependencies are not satisfied for " << APT::PrettyPkg(&Cache, I) << std::endl;
+      return true;
+   }
+
+   // a newly broken policy (recommends/suggests) is a problem
+   if (Cache[I].NowPolicyBroken() == false &&
+       Cache[I].InstPolicyBroken() == true)
+   {
+      if (Debug == true)
+        std::clog << "  Policy breaks with upgrade of " << APT::PrettyPkg(&Cache, I) << std::endl;
+      return true;
+   }
+
+   return false;
+}
+                                                                       /*}}}*/
 // ProblemResolver::ResolveByKeep - Resolve problems using keep                /*{{{*/
 // ---------------------------------------------------------------------
 /* This is the work horse of the soft upgrade routine. It is very gental 
    in that it does not install or remove any packages. It is assumed that the
    system was non-broken previously. */
-bool pkgProblemResolver::ResolveByKeep()
+bool pkgProblemResolver::ResolveByKeep(OpProgress * const Progress)
+{
+   std::string const solver = _config->Find("APT::Solver", "internal");
+   if (solver != "internal")
+      return EDSP::ResolveExternal(solver.c_str(), Cache, true, false, false, Progress);
+   return ResolveByKeepInternal();
+}
+                                                                       /*}}}*/
+// ProblemResolver::ResolveByKeepInternal - Resolve problems using keep        /*{{{*/
+// ---------------------------------------------------------------------
+/* This is the work horse of the soft upgrade routine. It is very gental
+   in that it does not install or remove any packages. It is assumed that the
+   system was non-broken previously. */
+bool pkgProblemResolver::ResolveByKeepInternal()
 {
    pkgDepCache::ActionGroup group(Cache);
 
@@ -1175,10 +1157,11 @@ bool pkgProblemResolver::ResolveByKeep()
       would cause the removal of even lower score packages. */
    pkgCache::Package **PList = new pkgCache::Package *[Size];
    pkgCache::Package **PEnd = PList;
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
       *PEnd++ = I;
-   This = this;
-   qsort(PList,PEnd - PList,sizeof(*PList),&ScoreSort);
+
+   std::sort(PList,PEnd,[this](Package *a, Package *b) { return ScoreSort(a, b) < 0; });
+
 
    if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true)
    {
@@ -1187,7 +1170,7 @@ bool pkgProblemResolver::ResolveByKeep()
          if (Scores[(*K)->ID] != 0)
          {
            pkgCache::PkgIterator Pkg(Cache,*K);
-           clog << Scores[(*K)->ID] << ' ' << Pkg << std::endl;
+           clog << Scores[(*K)->ID] << ' ' << APT::PrettyPkg(&Cache, Pkg) << std::endl;
          }
    }
 
@@ -1200,17 +1183,20 @@ bool pkgProblemResolver::ResolveByKeep()
    {
       pkgCache::PkgIterator I(Cache,*K);
 
-      if (Cache[I].InstallVer == 0 || Cache[I].InstBroken() == false)
+      if (Cache[I].InstallVer == 0)
         continue;
 
+      if (InstOrNewPolicyBroken(I) == false)
+         continue;
+
       /* Keep the package. If this works then great, otherwise we have
-                to be significantly more agressive and manipulate its dependencies */
+        to be significantly more aggressive and manipulate its dependencies */
       if ((Flags[I->ID] & Protected) == 0)
       {
         if (Debug == true)
-           clog << "Keeping package " << I.Name() << endl;
+           clog << "Keeping package " << I.FullName(false) << endl;
         Cache.MarkKeep(I, false, false);
-        if (Cache[I].InstBroken() == false)
+        if (InstOrNewPolicyBroken(I) == false)
         {
            K = PList - 1;
            continue;
@@ -1239,11 +1225,11 @@ bool pkgProblemResolver::ResolveByKeep()
         while (true)
         {
            if (Debug == true)
-              clog << "Package " << I.Name() << " has broken " << Start.DepType() << " on " << Start.TargetPkg().Name() << endl;
+              clog << "Package " << I.FullName(false) << " " << APT::PrettyDep(&Cache, Start) << endl;
 
            // Look at all the possible provides on this package
-           SPtrArray<pkgCache::Version *> VList = Start.AllTargets();
-           for (pkgCache::Version **V = VList; *V != 0; V++)
+           std::unique_ptr<pkgCache::Version *[]> VList(Start.AllTargets());
+           for (pkgCache::Version **V = VList.get(); *V != 0; V++)
            {
               pkgCache::VerIterator Ver(Cache,*V);
               pkgCache::PkgIterator Pkg = Ver.ParentPkg();
@@ -1256,47 +1242,55 @@ bool pkgProblemResolver::ResolveByKeep()
               if ((Flags[I->ID] & Protected) == 0)
               {
                  if (Debug == true)
-                    clog << "  Keeping Package " << Pkg.Name() << " due to " << Start.DepType() << endl;
+                    clog << "  Keeping Package " << Pkg.FullName(false) << " due to " << Start.DepType() << endl;
                  Cache.MarkKeep(Pkg, false, false);
               }
               
-              if (Cache[I].InstBroken() == false)
+              if (InstOrNewPolicyBroken(I) == false)
                  break;
            }
            
-           if (Cache[I].InstBroken() == false)
+           if (InstOrNewPolicyBroken(I) == false)
               break;
 
            if (Start == End)
               break;
-           Start++;
+           ++Start;
         }
              
-        if (Cache[I].InstBroken() == false)
+        if (InstOrNewPolicyBroken(I) == false)
            break;
       }
 
-      if (Cache[I].InstBroken() == true)
+      if (InstOrNewPolicyBroken(I) == true)
         continue;
       
       // Restart again.
-      if (K == LastStop)
-        return _error->Error("Internal Error, pkgProblemResolver::ResolveByKeep is looping on package %s.",I.Name());
+      if (K == LastStop) {
+          // I is an iterator based off our temporary package list,
+          // so copy the name we need before deleting the temporary list
+          std::string const LoopingPackage = I.FullName(false);
+          delete[] PList;
+          return _error->Error("Internal Error, pkgProblemResolver::ResolveByKeep is looping on package %s.", LoopingPackage.c_str());
+      }
       LastStop = K;
       K = PList - 1;
-   }   
+   }
 
+   delete[] PList;
    return true;
 }
                                                                        /*}}}*/
-// ProblemResolver::InstallProtect - Install all protected packages    /*{{{*/
+// ProblemResolver::InstallProtect - deprecated cpu-eating no-op       /*{{{*/
 // ---------------------------------------------------------------------
-/* This is used to make sure protected packages are installed */
+/* Actions issued with FromUser bit set are protected from further
+   modification (expect by other calls with FromUser set) nowadays , so we
+   don't need to reissue actions here, they are already set in stone. */
 void pkgProblemResolver::InstallProtect()
 {
    pkgDepCache::ActionGroup group(Cache);
 
-   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
    {
       if ((Flags[I->ID] & Protected) == Protected)
       {
@@ -1317,111 +1311,46 @@ void pkgProblemResolver::InstallProtect()
 // ---------------------------------------------------------------------
 /* This is ment to be used in conjunction with AllTargets to get a list 
    of versions ordered by preference. */
-static pkgCache *PrioCache;
-static int PrioComp(const void *A,const void *B)
-{
-   pkgCache::VerIterator L(*PrioCache,*(pkgCache::Version **)A);
-   pkgCache::VerIterator R(*PrioCache,*(pkgCache::Version **)B);
-   
-   if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential &&
-       (R.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential)
-     return 1;
-   if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential &&
-       (R.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
-     return -1;
-   
-   if (L->Priority != R->Priority)
-      return R->Priority - L->Priority;
-   return strcmp(L.ParentPkg().Name(),R.ParentPkg().Name());
-}
-void pkgPrioSortList(pkgCache &Cache,pkgCache::Version **List)
-{
-   unsigned long Count = 0;
-   PrioCache = &Cache;
-   for (pkgCache::Version **I = List; *I != 0; I++)
-      Count++;
-   qsort(List,Count,sizeof(*List),PrioComp);
-}
-                                                                       /*}}}*/
-// CacheFile::ListUpdate - update the cache files                      /*{{{*/
-// ---------------------------------------------------------------------
-/* This is a simple wrapper to update the cache. it will fetch stuff
- * from the network (or any other sources defined in sources.list)
- */
-bool ListUpdate(pkgAcquireStatus &Stat, 
-               pkgSourceList &List, 
-               int PulseInterval)
-{
-   pkgAcquire::RunResult res;
-   pkgAcquire Fetcher(&Stat);
-
-   // Populate it with the source selection
-   if (List.GetIndexes(&Fetcher) == false)
-        return false;
-
-   // Run scripts
-   RunScripts("APT::Update::Pre-Invoke");
-   
-   // check arguments
-   if(PulseInterval>0)
-      res = Fetcher.Run(PulseInterval);
-   else
-      res = Fetcher.Run();
-
-   if (res == pkgAcquire::Failed)
-      return false;
-
-   bool Failed = false;
-   bool TransientNetworkFailure = false;
-   for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin(); 
-       I != Fetcher.ItemsEnd(); I++)
-   {
-      if ((*I)->Status == pkgAcquire::Item::StatDone)
-        continue;
-
-      (*I)->Finished();
-
-      ::URI uri((*I)->DescURI());
-      uri.User.clear();
-      uri.Password.clear();
-      string descUri = string(uri);
-      _error->Warning(_("Failed to fetch %s  %s\n"), descUri.c_str(),
-             (*I)->ErrorText.c_str());
 
-      if ((*I)->Status == pkgAcquire::Item::StatTransientNetworkError) 
-      {
-        TransientNetworkFailure = true;
-        continue;
-      }
+struct PrioComp {
+   pkgCache &PrioCache;
 
-      Failed = true;
+   explicit PrioComp(pkgCache &PrioCache) : PrioCache(PrioCache) {
    }
-   
-   // Clean out any old list files
-   // Keep "APT::Get::List-Cleanup" name for compatibility, but
-   // this is really a global option for the APT library now
-   if (!TransientNetworkFailure && !Failed &&
-       (_config->FindB("APT::Get::List-Cleanup",true) == true &&
-       _config->FindB("APT::List-Cleanup",true) == true))
-   {
-      if (Fetcher.Clean(_config->FindDir("Dir::State::lists")) == false ||
-         Fetcher.Clean(_config->FindDir("Dir::State::lists") + "partial/") == false)
-        // something went wrong with the clean
-        return false;
-   }
-   
-   if (TransientNetworkFailure == true)
-      _error->Warning(_("Some index files failed to download, they have been ignored, or old ones used instead."));
-   else if (Failed == true)
-      return _error->Error(_("Some index files failed to download, they have been ignored, or old ones used instead."));
 
+   bool operator() (pkgCache::Version * const &A, pkgCache::Version * const &B) {
+      return compare(A, B) < 0;
+   }
 
-   // Run the success scripts if all was fine
-   if(!TransientNetworkFailure && !Failed)
-      RunScripts("APT::Update::Post-Invoke-Success");
+   int compare(pkgCache::Version * const &A, pkgCache::Version * const &B) {
+      pkgCache::VerIterator L(PrioCache,A);
+      pkgCache::VerIterator R(PrioCache,B);
+
+      if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential &&
+         (R.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential)
+       return 1;
+      if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential &&
+         (R.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
+       return -1;
+
+      if ((L.ParentPkg()->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important &&
+         (R.ParentPkg()->Flags & pkgCache::Flag::Important) != pkgCache::Flag::Important)
+       return 1;
+      if ((L.ParentPkg()->Flags & pkgCache::Flag::Important) != pkgCache::Flag::Important &&
+         (R.ParentPkg()->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important)
+       return -1;
+
+      if (L->Priority != R->Priority)
+        return R->Priority - L->Priority;
+      return strcmp(L.ParentPkg().Name(),R.ParentPkg().Name());
+   }
+};
 
-   // Run the other scripts
-   RunScripts("APT::Update::Post-Invoke");
-   return true;
+void pkgPrioSortList(pkgCache &Cache,pkgCache::Version **List)
+{
+   unsigned long Count = 0;
+   for (pkgCache::Version **I = List; *I != 0; I++)
+      Count++;
+   std::sort(List,List+Count,PrioComp(Cache));
 }
                                                                        /*}}}*/