]> git.saurik.com Git - apt.git/blobdiff - apt-pkg/depcache.cc
merge MultiArch-ABI. We don't support MultiArch yet (as most other tools),
[apt.git] / apt-pkg / depcache.cc
index 8560ce4fda120cbf9b388c440193dd961f492a49..75f69ee116a13b3c88ae7e0ce77ff9642830b2a8 100644 (file)
@@ -8,24 +8,84 @@
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
-#ifdef __GNUG__
-#pragma implementation "apt-pkg/depcache.h"
-#endif
 #include <apt-pkg/depcache.h>
 #include <apt-pkg/version.h>
 #include <apt-pkg/error.h>
 #include <apt-pkg/sptr.h>
 #include <apt-pkg/algorithms.h>
+
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/strutl.h>
 #include <apt-pkg/configuration.h>
+#include <apt-pkg/aptconfiguration.h>
+#include <apt-pkg/pkgsystem.h>
+#include <apt-pkg/tagfile.h>
+
+#include <iostream>
+#include <sstream>    
+#include <set>
+
+#include <sys/stat.h>
+
 #include <apti18n.h>    
                                                                        /*}}}*/
+// helper for Install-Recommends-Sections and Never-MarkAuto-Sections  /*{{{*/
+static bool 
+ConfigValueInSubTree(const char* SubTree, const char *needle)
+{
+   Configuration::Item const *Opts;
+   Opts = _config->Tree(SubTree);
+   if (Opts != 0 && Opts->Child != 0)
+   {
+      Opts = Opts->Child;
+      for (; Opts != 0; Opts = Opts->Next)
+      {
+        if (Opts->Value.empty() == true)
+           continue;
+        if (strcmp(needle, Opts->Value.c_str()) == 0)
+           return true;
+      }
+   }
+   return false;
+}
+                                                                       /*}}}*/
+pkgDepCache::ActionGroup::ActionGroup(pkgDepCache &cache) :            /*{{{*/
+  cache(cache), released(false)
+{
+  ++cache.group_level;
+}
 
+void pkgDepCache::ActionGroup::release()
+{
+  if(!released)
+    {
+      if(cache.group_level == 0)
+       std::cerr << "W: Unbalanced action groups, expect badness" << std::endl;
+      else
+       {
+         --cache.group_level;
+
+         if(cache.group_level == 0)
+           cache.MarkAndSweep();
+       }
+
+      released = false;
+    }
+}
+
+pkgDepCache::ActionGroup::~ActionGroup()
+{
+  release();
+}
+                                                                       /*}}}*/
 // DepCache::pkgDepCache - Constructors                                        /*{{{*/
 // ---------------------------------------------------------------------
 /* */
 pkgDepCache::pkgDepCache(pkgCache *pCache,Policy *Plcy) :
-                Cache(pCache), PkgState(0), DepState(0)
+  group_level(0), Cache(pCache), PkgState(0), DepState(0)
 {
+   DebugMarker = _config->FindB("Debug::pkgDepCache::Marker", false);
+   DebugAutoInstall = _config->FindB("Debug::pkgDepCache::AutoInstall", false);
    delLocalPolicy = 0;
    LocalPolicy = Plcy;
    if (LocalPolicy == 0)
@@ -47,6 +107,10 @@ pkgDepCache::~pkgDepCache()
 /* This allocats the extension buffers and initializes them. */
 bool pkgDepCache::Init(OpProgress *Prog)
 {
+   // Suppress mark updates during this operation (just in case) and
+   // run a mark operation when Init terminates.
+   ActionGroup actions(*this);
+
    delete [] PkgState;
    delete [] DepState;
    PkgState = new StateCache[Head().PackageCount];
@@ -66,13 +130,13 @@ bool pkgDepCache::Init(OpProgress *Prog)
    int Done = 0;
    for (PkgIterator I = PkgBegin(); I.end() != true; I++,Done++)
    {
-      if (Prog != 0)
+      if (Prog != 0 && Done%20 == 0)
         Prog->Progress(Done);
       
       // Find the proper cache slot
       StateCache &State = PkgState[I->ID];
       State.iFlags = 0;
-      
+
       // Figure out the install version
       State.CandidateVer = GetCandidateVer(I);
       State.InstallVer = I.CurrentVer();
@@ -94,11 +158,173 @@ bool pkgDepCache::Init(OpProgress *Prog)
 
    if(Prog != 0)
       Prog->Done();
-   
+
    return true;
 } 
                                                                        /*}}}*/
+bool pkgDepCache::readStateFile(OpProgress *Prog)                      /*{{{*/
+{
+   FileFd state_file;
+   string const state = _config->FindDir("Dir::State") + "extended_states";
+   if(FileExists(state)) {
+      state_file.Open(state, FileFd::ReadOnly);
+      int const file_size = state_file.Size();
+      if(Prog != NULL)
+        Prog->OverallProgress(0, file_size, 1, 
+                              _("Reading state information"));
+
+      pkgTagFile tagfile(&state_file);
+      pkgTagSection section;
+      int amt = 0;
+      bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
+      while(tagfile.Step(section)) {
+        string const pkgname = section.FindS("Package");
+        string pkgarch = section.FindS("Architecture");
+        if (pkgarch.empty() == true)
+           pkgarch = "any";
+        pkgCache::PkgIterator pkg = Cache->FindPkg(pkgname, pkgarch);
+        // Silently ignore unknown packages and packages with no actual version.
+        if(pkg.end() == true || pkg->VersionList == 0)
+           continue;
+
+        short const reason = section.FindI("Auto-Installed", 0);
+        if(reason > 0)
+        {
+           PkgState[pkg->ID].Flags |= Flag::Auto;
+           if (unlikely(debug_autoremove))
+              std::cout << "Auto-Installed : " << pkg.FullName() << std::endl;
+           if (pkgarch == "any")
+           {
+              pkgCache::GrpIterator G = pkg.Group();
+              for (pkg = G.NextPkg(pkg); pkg.end() != true; pkg = G.NextPkg(pkg))
+                 if (pkg->VersionList != 0)
+                    PkgState[pkg->ID].Flags |= Flag::Auto;
+           }
+        }
+        amt += section.size();
+        if(Prog != NULL)
+           Prog->OverallProgress(amt, file_size, 1, 
+                                 _("Reading state information"));
+      }
+      if(Prog != NULL)
+        Prog->OverallProgress(file_size, file_size, 1,
+                              _("Reading state information"));
+   }
+
+   return true;
+}
+                                                                       /*}}}*/
+bool pkgDepCache::writeStateFile(OpProgress *prog, bool InstalledOnly) /*{{{*/
+{
+   bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
+   
+   if(debug_autoremove)
+      std::clog << "pkgDepCache::writeStateFile()" << std::endl;
+
+   FileFd StateFile;
+   string const state = _config->FindDir("Dir::State") + "extended_states";
+
+   // if it does not exist, create a empty one
+   if(!FileExists(state)) 
+   {
+      StateFile.Open(state, FileFd::WriteEmpty);
+      StateFile.Close();
+   }
 
+   // open it
+   if(!StateFile.Open(state, FileFd::ReadOnly))
+      return _error->Error(_("Failed to open StateFile %s"),
+                          state.c_str());
+
+   FILE *OutFile;
+   string const outfile = state + ".tmp";
+   if((OutFile = fopen(outfile.c_str(),"w")) == NULL)
+      return _error->Error(_("Failed to write temporary StateFile %s"),
+                          outfile.c_str());
+
+   // first merge with the existing sections
+   pkgTagFile tagfile(&StateFile);
+   pkgTagSection section;
+   std::set<string> pkgs_seen;
+   const char *nullreorderlist[] = {0};
+   while(tagfile.Step(section)) {
+        string const pkgname = section.FindS("Package");
+        string pkgarch = section.FindS("Architecture");
+        if (pkgarch.empty() == true)
+           pkgarch = "native";
+        // Silently ignore unknown packages and packages with no actual
+        // version.
+        pkgCache::PkgIterator pkg = Cache->FindPkg(pkgname, pkgarch);
+        if(pkg.end() || pkg.VersionList().end()) 
+           continue;
+        StateCache const &P = PkgState[pkg->ID];
+        bool newAuto = (P.Flags & Flag::Auto);
+        // skip not installed or now-removed ones if requested
+        if (InstalledOnly && (
+            (pkg->CurrentVer == 0 && P.Mode != ModeInstall) ||
+            (pkg->CurrentVer != 0 && P.Mode == ModeDelete)))
+        {
+           // The section is obsolete if it contains no other tag
+           unsigned int const count = section.Count();
+           if (count < 2 ||
+               (count == 2 && section.Exists("Auto-Installed")) ||
+               (count == 3 && section.Exists("Auto-Installed") && section.Exists("Architecture")))
+              continue;
+           else
+              newAuto = false;
+        }
+        if(_config->FindB("Debug::pkgAutoRemove",false))
+           std::clog << "Update existing AutoInstall info: " 
+                     << pkg.FullName() << std::endl;
+        TFRewriteData rewrite[3];
+        rewrite[0].Tag = "Architecture";
+        rewrite[0].Rewrite = pkg.Arch();
+        rewrite[0].NewTag = 0;
+        rewrite[1].Tag = "Auto-Installed";
+        rewrite[1].Rewrite = newAuto ? "1" : "0";
+        rewrite[1].NewTag = 0;
+        rewrite[2].Tag = 0;
+        TFRewrite(OutFile, section, nullreorderlist, rewrite);
+        fprintf(OutFile,"\n");
+        pkgs_seen.insert(pkg.FullName());
+   }
+   
+   // then write the ones we have not seen yet
+   std::ostringstream ostr;
+   for(pkgCache::PkgIterator pkg=Cache->PkgBegin(); !pkg.end(); pkg++) {
+      StateCache const &P = PkgState[pkg->ID];
+      if(P.Flags & Flag::Auto) {
+        if (pkgs_seen.find(pkg.FullName()) != pkgs_seen.end()) {
+           if(debug_autoremove)
+              std::clog << "Skipping already written " << pkg.FullName() << std::endl;
+           continue;
+        }
+        // skip not installed ones if requested
+        if (InstalledOnly && (
+            (pkg->CurrentVer == 0 && P.Mode != ModeInstall) ||
+            (pkg->CurrentVer != 0 && P.Mode == ModeDelete)))
+           continue;
+        const char* const pkgarch = pkg.Arch();
+        if (strcmp(pkgarch, "all") == 0)
+           continue;
+        if(debug_autoremove)
+           std::clog << "Writing new AutoInstall: " << pkg.FullName() << std::endl;
+        ostr.str(string(""));
+        ostr << "Package: " << pkg.Name()
+             << "\nArchitecture: " << pkgarch
+             << "\nAuto-Installed: 1\n\n";
+        fprintf(OutFile,"%s",ostr.str().c_str());
+      }
+   }
+   fclose(OutFile);
+
+   // move the outfile over the real file and set permissions
+   rename(outfile.c_str(), state.c_str());
+   chmod(state.c_str(), 0644);
+
+   return true;
+}
+                                                                       /*}}}*/
 // DepCache::CheckDep - Checks a single dependency                     /*{{{*/
 // ---------------------------------------------------------------------
 /* This first checks the dependency against the main target package and
@@ -113,7 +339,7 @@ bool pkgDepCache::CheckDep(DepIterator Dep,int Type,PkgIterator &Res)
       we allow it anyhow because dpkg does. Technically it is a packaging
       bug. Conflicts may never self match */
    if (Dep.TargetPkg() != Dep.ParentPkg() || 
-       (Dep->Type != Dep::Conflicts && Dep->Type != Dep::Obsoletes))
+       (Dep->Type != Dep::Conflicts && Dep->Type != Dep::DpkgBreaks && Dep->Type != Dep::Obsoletes))
    {
       PkgIterator Pkg = Dep.TargetPkg();
       // Check the base package
@@ -143,7 +369,8 @@ bool pkgDepCache::CheckDep(DepIterator Dep,int Type,PkgIterator &Res)
    {
       /* Provides may never be applied against the same package if it is
          a conflicts. See the comment above. */
-      if (P.OwnerPkg() == Pkg && Dep->Type == Dep::Conflicts)
+      if (P.OwnerPkg() == Pkg &&
+         (Dep->Type == Dep::Conflicts || Dep->Type == Dep::DpkgBreaks))
         continue;
       
       // Check if the provides is a hit
@@ -239,9 +466,11 @@ void pkgDepCache::AddStates(const PkgIterator &Pkg,int Add)
 {
    StateCache &State = PkgState[Pkg->ID];
    
-   // The Package is broken
+   // The Package is broken (either minimal dep or policy dep)
    if ((State.DepState & DepInstMin) != DepInstMin)
       iBrokenCount += Add;
+   if ((State.DepState & DepInstPolicy) != DepInstPolicy)
+      iPolicyBrokenCount += Add;
    
    // Bad state
    if (Pkg.State() != PkgIterator::NeedsNothing)
@@ -295,7 +524,9 @@ void pkgDepCache::BuildGroupOrs(VerIterator const &V)
 
       /* Invert for Conflicts. We have to do this twice to get the
          right sense for a conflicts group */
-      if (D->Type == Dep::Conflicts || D->Type == Dep::Obsoletes)
+      if (D->Type == Dep::Conflicts ||
+         D->Type == Dep::DpkgBreaks ||
+         D->Type == Dep::Obsoletes)
         State = ~State;
       
       // Add to the group if we are within an or..
@@ -306,7 +537,9 @@ void pkgDepCache::BuildGroupOrs(VerIterator const &V)
         Group = 0;
       
       // Invert for Conflicts
-      if (D->Type == Dep::Conflicts || D->Type == Dep::Obsoletes)
+      if (D->Type == Dep::Conflicts ||
+         D->Type == Dep::DpkgBreaks ||
+         D->Type == Dep::Obsoletes)
         State = ~State;
    }    
 }
@@ -402,6 +635,107 @@ void pkgDepCache::UpdateVerState(PkgIterator Pkg)
    }
 }
                                                                        /*}}}*/
+// DepCache::RemovePseudoInstalledPkg - MultiArch helper for Update()  /*{{{*/
+// ---------------------------------------------------------------------
+/* We "install" arch all packages for all archs if it is installed. Many
+   of these will be broken. This method will look at these broken Pkg and
+   "remove" it. */
+bool pkgDepCache::RemovePseudoInstalledPkg(PkgIterator &Pkg, std::set<unsigned long> &recheck) {
+   if (unlikely(Pkg->CurrentVer == 0))
+      return false;
+
+   VerIterator V = Pkg.CurrentVer();
+   if (V->MultiArch != Version::All)
+      return false;
+
+   // Never ever kill an "all" package - they have no dependency so they can't be broken
+   if (strcmp(Pkg.Arch(),"all") == 0)
+      return false;
+
+   unsigned char const CurDepState = VersionState(V.DependsList(),DepInstall,DepInstMin,DepInstPolicy);
+   if ((CurDepState & DepInstMin) == DepInstMin) {
+      // okay, the package isn't broken, but is the package also required?
+      // If it has no real dependencies, no installed rdepends and doesn't
+      // provide something of value, we will kill it as not required.
+      // These pseudopackages have otherwise interesting effects if they get
+      // a new dependency in a newer version…
+      for (pkgCache::DepIterator D = V.DependsList();
+          D.end() != true; ++D)
+        if (D.IsCritical() == true && D.ParentPkg()->Group != Pkg->Group)
+           return false;
+      for (DepIterator D = Pkg.RevDependsList(); D.end() != true; ++D)
+      {
+        if (D.IsCritical() == false)
+           continue;
+        PkgIterator const P = D.ParentPkg();
+        if (P->Group == Pkg->Group)
+           continue;
+        if (P->CurrentVer != 0)
+           return false;
+      }
+      for (PrvIterator Prv = V.ProvidesList(); Prv.end() != true; Prv++)
+        for (DepIterator d = Prv.ParentPkg().RevDependsList();
+             d.end() != true; ++d)
+        {
+           PkgIterator const P = d.ParentPkg();
+           if (P->CurrentVer != 0 &&
+               P->Group != Pkg->Group)
+              return false;
+        }
+   }
+
+   // Dependencies for this arch all package are not statisfied
+   // so we installed it only for our convenience: get right of it now.
+   RemoveSizes(Pkg);
+   RemoveStates(Pkg);
+
+   Pkg->CurrentVer = 0;
+   PkgState[Pkg->ID].InstallVer = 0;
+
+   AddStates(Pkg);
+   Update(Pkg);
+   AddSizes(Pkg);
+
+   // After the remove previously satisfied pseudo pkg could be now
+   // no longer satisfied, so we need to recheck the reverse dependencies
+   for (DepIterator d = Pkg.RevDependsList(); d.end() != true; ++d)
+   {
+      PkgIterator const P = d.ParentPkg();
+      if (P->CurrentVer != 0)
+        recheck.insert(P.Index());
+   }
+
+   for (DepIterator d = V.DependsList(); d.end() != true; ++d)
+   {
+      PkgIterator const P = d.TargetPkg();
+      for (PrvIterator Prv = P.ProvidesList(); Prv.end() != true; ++Prv)
+      {
+        PkgIterator const O = Prv.OwnerPkg();
+        if (O->CurrentVer != 0)
+           recheck.insert(O.Index());
+      }
+
+      if (P->CurrentVer != 0)
+        recheck.insert(P.Index());
+   }
+
+   for (PrvIterator Prv = V.ProvidesList(); Prv.end() != true; Prv++)
+   {
+      for (DepIterator d = Prv.ParentPkg().RevDependsList();
+          d.end() != true; ++d)
+      {
+        PkgIterator const P = d.ParentPkg();
+        if (P->CurrentVer == 0)
+           continue;
+
+           recheck.insert(P.Index());
+      }
+   }
+
+
+   return true;
+}
+                                                                       /*}}}*/
 // DepCache::Update - Figure out all the state information             /*{{{*/
 // ---------------------------------------------------------------------
 /* This will figure out the state of all the packages and all the 
@@ -415,9 +749,13 @@ void pkgDepCache::Update(OpProgress *Prog)
    iKeepCount = 0;
    iBrokenCount = 0;
    iBadCount = 0;
-   
+
+   std::set<unsigned long> recheck;
+
    // Perform the depends pass
    int Done = 0;
+   bool const checkMultiArch = APT::Configuration::getArchitectures().size() > 1;
+   unsigned long killed = 0;
    for (PkgIterator I = PkgBegin(); I.end() != true; I++,Done++)
    {
       if (Prog != 0 && Done%20 == 0)
@@ -425,7 +763,7 @@ void pkgDepCache::Update(OpProgress *Prog)
       for (VerIterator V = I.VersionList(); V.end() != true; V++)
       {
         unsigned char Group = 0;
-        
+
         for (DepIterator D = V.DependsList(); D.end() != true; D++)
         {
            // Build the dependency state.
@@ -439,25 +777,118 @@ void pkgDepCache::Update(OpProgress *Prog)
               Group = 0;
 
            // Invert for Conflicts
-           if (D->Type == Dep::Conflicts || D->Type == Dep::Obsoletes)
+           if (D->Type == Dep::Conflicts ||
+               D->Type == Dep::DpkgBreaks ||
+               D->Type == Dep::Obsoletes)
               State = ~State;
-        }       
+        }
       }
 
-      // Compute the pacakge dependency state and size additions
+      // Compute the package dependency state and size additions
       AddSizes(I);
       UpdateVerState(I);
       AddStates(I);
+
+      if (checkMultiArch != true || I->CurrentVer == 0)
+        continue;
+
+      VerIterator const V = I.CurrentVer();
+      if (V->MultiArch != Version::All)
+        continue;
+
+      recheck.insert(I.Index());
+      --Done; // no progress if we need to recheck the package
    }
 
-   if (Prog != 0)      
+   if (checkMultiArch == true) {
+      /* FIXME: recheck breaks proper progress reporting as we don't know
+               how many packages we need to recheck. To lower the effect
+               a bit we increase with a kill, but we should do something more clever… */
+      for(std::set<unsigned long>::const_iterator p = recheck.begin();
+         p != recheck.end(); ++p) {
+        if (Prog != 0 && Done%20 == 0)
+           Prog->Progress(Done);
+        PkgIterator P = PkgIterator(*Cache, Cache->PkgP + *p);
+        if (RemovePseudoInstalledPkg(P, recheck) == true) {
+           ++killed;
+           ++Done;
+        }
+        recheck.erase(p);
+      }
+
+      /* Okay, we have killed a great amount of pseudopackages -
+        we have killed so many that we have now arch "all" packages
+        without an installed pseudo package, but we NEED an installed
+        pseudo package, so we will search now for a pseudo package
+        we can install without breaking everything. */
+      for (GrpIterator G = Cache->GrpBegin(); G.end() != true; ++G)
+      {
+        PkgIterator P = G.FindPkg("all");
+        if (P.end() == true)
+           continue;
+        if (P->CurrentVer == 0)
+           continue;
+        bool installed = false;
+        for (P = G.FindPkg("any"); P.end() != true; P = G.NextPkg(P))
+        {
+           if (strcmp(P.Arch(), "all") == 0)
+              continue;
+           if (P->CurrentVer == 0)
+              continue;
+           installed = true;
+           break;
+        }
+        if (installed == false)
+           recheck.insert(G.Index());
+      }
+      std::vector<std::string> Archs = APT::Configuration::getArchitectures();
+      bool checkChanged = false;
+      do {
+        for(std::set<unsigned long>::const_iterator g = recheck.begin();
+            g != recheck.end(); ++g) {
+           GrpIterator G = GrpIterator(*Cache, Cache->GrpP + *g);
+           VerIterator allV = G.FindPkg("all").CurrentVer();
+           for (std::vector<std::string>::const_iterator a = Archs.begin();
+                a != Archs.end(); ++a)
+           {
+              PkgIterator P = G.FindPkg(*a);
+              if (P.end() == true) continue;
+              for (VerIterator V = P.VersionList(); V.end() != true; ++V)
+              {
+                 // FIXME: String comparison isn't a save indicator!
+                 if (strcmp(allV.VerStr(),V.VerStr()) != 0)
+                    continue;
+                 unsigned char const CurDepState = VersionState(V.DependsList(),DepInstall,DepInstMin,DepInstPolicy);
+                 if ((CurDepState & DepInstMin) != DepInstMin)
+                    break; // we found the correct version, but it is broken. Better try another arch or later again
+                 P->CurrentVer = V.Index();
+                 AddStates(P);
+                 Update(P);
+                 AddSizes(P);
+                 checkChanged = true;
+                 break;
+              }
+           }
+           recheck.erase(g);
+        }
+      } while (checkChanged == true && recheck.empty() == false);
+
+      if (_config->FindB("Debug::MultiArchKiller", false) == true)
+        for(std::set<unsigned long>::const_iterator g = recheck.begin();
+            g != recheck.end(); ++g)
+           std::cout << "No pseudo package for Â»" << GrpIterator(*Cache, Cache->GrpP + *g).Name() << "« installed" << std::endl;
+   }
+
+   if (Prog != 0)
       Prog->Progress(Done);
+
+   readStateFile(Prog);
 }
                                                                        /*}}}*/
 // DepCache::Update - Update the deps list of a package                        /*{{{*/
 // ---------------------------------------------------------------------
 /* This is a helper for update that only does the dep portion of the scan. 
-   It is mainly ment to scan reverse dependencies. */
+   It is mainly meant to scan reverse dependencies. */
 void pkgDepCache::Update(DepIterator D)
 {
    // Update the reverse deps
@@ -467,7 +898,9 @@ void pkgDepCache::Update(DepIterator D)
       State = DependencyState(D);
     
       // Invert for Conflicts
-      if (D->Type == Dep::Conflicts || D->Type == Dep::Obsoletes)
+      if (D->Type == Dep::Conflicts ||
+         D->Type == Dep::DpkgBreaks ||
+         D->Type == Dep::Obsoletes)
         State = ~State;
 
       RemoveStates(D.ParentPkg());
@@ -503,13 +936,12 @@ void pkgDepCache::Update(PkgIterator const &Pkg)
           P.end() != true; P++)
         Update(P.ParentPkg().RevDependsList());
 }
-
                                                                        /*}}}*/
-
 // DepCache::MarkKeep - Put the package in the keep state              /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void pkgDepCache::MarkKeep(PkgIterator const &Pkg,bool Soft)
+void pkgDepCache::MarkKeep(PkgIterator const &Pkg, bool Soft, bool FromUser,
+                           unsigned long Depth)
 {
    // Simplifies other routines.
    if (Pkg.end() == true)
@@ -521,6 +953,9 @@ void pkgDepCache::MarkKeep(PkgIterator const &Pkg,bool Soft)
        Pkg.CurrentVer().Downloadable() == false)
       return;
    
+   /** \todo Can this be moved later in the method? */
+   ActionGroup group(*this);
+
    /* We changed the soft state all the time so the UI is a bit nicer
       to use */
    StateCache &P = PkgState[Pkg->ID];
@@ -536,8 +971,20 @@ void pkgDepCache::MarkKeep(PkgIterator const &Pkg,bool Soft)
    // We dont even try to keep virtual packages..
    if (Pkg->VersionList == 0)
       return;
-   
-   P.Flags &= ~Flag::Auto;
+#if 0 // reseting the autoflag here means we lose the 
+      // auto-mark information if a user selects a package for removal
+      // but changes  his mind then and sets it for keep again
+      // - this makes sense as default when all Garbage dependencies
+      //   are automatically marked for removal (as aptitude does).
+      //   setting a package for keep then makes it no longer autoinstalled
+      //   for all other use-case this action is rather suprising
+   if(FromUser && !P.Marked)
+     P.Flags &= ~Flag::Auto;
+#endif
+
+   if (DebugMarker == true)
+      std::clog << OutputInDepth(Depth) << "MarkKeep " << Pkg << " FU=" << FromUser << std::endl;
+
    RemoveSizes(Pkg);
    RemoveStates(Pkg);
 
@@ -557,12 +1004,15 @@ void pkgDepCache::MarkKeep(PkgIterator const &Pkg,bool Soft)
 // DepCache::MarkDelete - Put the package in the delete state          /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void pkgDepCache::MarkDelete(PkgIterator const &Pkg, bool rPurge)
+void pkgDepCache::MarkDelete(PkgIterator const &Pkg, bool rPurge,
+                             unsigned long Depth, bool FromUser)
 {
    // Simplifies other routines.
    if (Pkg.end() == true)
       return;
 
+   ActionGroup group(*this);
+
    // Check that it is not already marked for delete
    StateCache &P = PkgState[Pkg->ID];
    P.iFlags &= ~(AutoKept | Purge);
@@ -577,6 +1027,13 @@ void pkgDepCache::MarkDelete(PkgIterator const &Pkg, bool rPurge)
    if (Pkg->VersionList == 0)
       return;
 
+   // check if we are allowed to install the package
+   if (IsDeleteOk(Pkg,rPurge,Depth,FromUser) == false)
+      return;
+
+   if (DebugMarker == true)
+      std::clog << OutputInDepth(Depth) << "MarkDelete " << Pkg << " FU=" << FromUser << std::endl;
+
    RemoveSizes(Pkg);
    RemoveStates(Pkg);
    
@@ -585,18 +1042,39 @@ void pkgDepCache::MarkDelete(PkgIterator const &Pkg, bool rPurge)
    else
       P.Mode = ModeDelete;
    P.InstallVer = 0;
-   P.Flags &= Flag::Auto;
 
    AddStates(Pkg);   
    Update(Pkg);
    AddSizes(Pkg);
+
+   // if we remove the pseudo package, we also need to remove the "real"
+   if (Pkg->CurrentVer != 0 && Pkg.CurrentVer().Pseudo() == true)
+      MarkDelete(Pkg.Group().FindPkg("all"), rPurge, Depth+1, FromUser);
+}
+                                                                       /*}}}*/
+// DepCache::IsDeleteOk - check if it is ok to remove this package     /*{{{*/
+// ---------------------------------------------------------------------
+/* The default implementation just honors dpkg hold
+   But an application using this library can override this method
+   to control the MarkDelete behaviour */
+bool pkgDepCache::IsDeleteOk(PkgIterator const &Pkg,bool rPurge,
+                             unsigned long Depth, bool FromUser)
+{
+   if (FromUser == false && Pkg->SelectedState == pkgCache::State::Hold && _config->FindB("APT::Ignore-Hold",false) == false)
+   {
+      if (DebugMarker == true)
+        std::clog << OutputInDepth(Depth) << "Hold prevents MarkDelete of " << Pkg << " FU=" << FromUser << std::endl;
+      return false;
+   }
+   return true;
 }
                                                                        /*}}}*/
 // DepCache::MarkInstall - Put the package in the install state                /*{{{*/
 // ---------------------------------------------------------------------
 /* */
 void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
-                             unsigned long Depth)
+                             unsigned long Depth, bool FromUser,
+                             bool ForceImportantDeps)
 {
    if (Depth > 100)
       return;
@@ -605,6 +1083,8 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
    if (Pkg.end() == true)
       return;
    
+   ActionGroup group(*this);
+
    /* Check that it is not already marked for install and that it can be 
       installed */
    StateCache &P = PkgState[Pkg->ID];
@@ -614,7 +1094,7 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
        P.CandidateVer == (Version *)Pkg.CurrentVer()))
    {
       if (P.CandidateVer == (Version *)Pkg.CurrentVer() && P.InstallVer == 0)
-        MarkKeep(Pkg);
+        MarkKeep(Pkg, false, FromUser, Depth+1);
       return;
    }
 
@@ -624,6 +1104,11 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
    // We dont even try to install virtual packages..
    if (Pkg->VersionList == 0)
       return;
+
+   // check if we are allowed to install the package
+   if (IsInstallOk(Pkg,AutoInst,Depth,FromUser) == false)
+      return;
+
    /* Target the candidate version and remove the autoflag. We reset the
       autoflag below if this was called recursively. Otherwise the user
       should have the ability to de-auto a package by changing its state */
@@ -632,17 +1117,33 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
    
    P.Mode = ModeInstall;
    P.InstallVer = P.CandidateVer;
-   P.Flags &= ~Flag::Auto;
+
+   if(FromUser)
+     {
+       // Set it to manual if it's a new install or cancelling the
+       // removal of a garbage package.
+       if(P.Status == 2 || (!Pkg.CurrentVer().end() && !P.Marked))
+        P.Flags &= ~Flag::Auto;
+     }
+   else
+     {
+       // Set it to auto if this is a new install.
+       if(P.Status == 2)
+        P.Flags |= Flag::Auto;
+     }
    if (P.CandidateVer == (Version *)Pkg.CurrentVer())
       P.Mode = ModeKeep;
        
    AddStates(Pkg);
    Update(Pkg);
    AddSizes(Pkg);
-   
+
    if (AutoInst == false)
       return;
 
+   if (DebugMarker == true)
+      std::clog << OutputInDepth(Depth) << "MarkInstall " << Pkg << " FU=" << FromUser << std::endl;
+
    DepIterator Dep = P.InstVerIter(*this).DependsList();
    for (; Dep.end() != true;)
    {
@@ -664,10 +1165,66 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
 
       /* Check if this dep should be consider for install. If it is a user
          defined important dep and we are installed a new package then 
-        it will be installed. Otherwise we only worry about critical deps */
+        it will be installed. Otherwise we only check for important
+         deps that have changed from the installed version
+      */
       if (IsImportantDep(Start) == false)
         continue;
-      if (Pkg->CurrentVer != 0 && Start.IsCritical() == false)
+      
+      /* Check if any ImportantDep() (but not Critical) were added
+       * since we installed the package.  Also check for deps that
+       * were satisfied in the past: for instance, if a version
+       * restriction in a Recommends was tightened, upgrading the
+       * package should follow that Recommends rather than causing the
+       * dependency to be removed. (bug #470115)
+       */
+      bool isNewImportantDep = false;
+      bool isPreviouslySatisfiedImportantDep = false;
+      if(!ForceImportantDeps && !Start.IsCritical())
+      {
+        bool found=false;
+        VerIterator instVer = Pkg.CurrentVer();
+        if(!instVer.end())
+        {
+          for (DepIterator D = instVer.DependsList(); D.end() != true; D++)
+            {
+              //FIXME: deal better with or-groups(?)
+              DepIterator LocalStart = D;
+
+              if(IsImportantDep(D) && !D.IsCritical() &&
+                 Start.TargetPkg() == D.TargetPkg())
+                {
+                  if(!isPreviouslySatisfiedImportantDep)
+                    {
+                      DepIterator D2 = D;
+                      while((D2->CompareOp & Dep::Or) != 0)
+                        ++D2;
+
+                      isPreviouslySatisfiedImportantDep =
+                        (((*this)[D2] & DepGNow) != 0);
+                    }
+
+                  found=true;
+                }
+            }
+           // this is a new dep if it was not found to be already
+           // a important dep of the installed pacakge
+           isNewImportantDep = !found;
+        }
+      }
+      if(isNewImportantDep)
+        if(DebugAutoInstall == true)
+           std::clog << OutputInDepth(Depth) << "new important dependency: "
+                     << Start.TargetPkg().Name() << std::endl;
+      if(isPreviouslySatisfiedImportantDep)
+       if(DebugAutoInstall == true)
+         std::clog << OutputInDepth(Depth) << "previously satisfied important dependency on "
+                   << Start.TargetPkg().Name() << std::endl;
+
+      // skip important deps if the package is already installed
+      if (Pkg->CurrentVer != 0 && Start.IsCritical() == false 
+         && !isNewImportantDep && !isPreviouslySatisfiedImportantDep
+         && !ForceImportantDeps)
         continue;
       
       /* If we are in an or group locate the first or that can 
@@ -678,7 +1235,8 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
       /* This bit is for processing the possibilty of an install/upgrade
          fixing the problem */
       SPtrArray<Version *> List = Start.AllTargets();
-      if ((DepState[Start->ID] & DepCVer) == DepCVer)
+      if (Start->Type != Dep::DpkgBreaks &&
+         (DepState[Start->ID] & DepCVer) == DepCVer)
       {
         // Right, find the best version to install..
         Version **Cur = List;
@@ -711,42 +1269,75 @@ void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
         
         if (InstPkg.end() == false)
         {
-           if(_config->FindB("Debug::pkgDepCache::AutoInstall",false) == true)
-              std::clog << "Installing " << InstPkg.Name() 
-                        << " as dep of " << Pkg.Name() 
+           if(DebugAutoInstall == true)
+              std::clog << OutputInDepth(Depth) << "Installing " << InstPkg.Name()
+                        << " as " << Start.DepType() << " of " << Pkg.Name()
                         << std::endl;
-           MarkInstall(InstPkg,true,Depth + 1);
-
-           // Set the autoflag, after MarkInstall because MarkInstall unsets it
-           if (P->CurrentVer == 0)
-              PkgState[InstPkg->ID].Flags |= Flag::Auto;
+           // now check if we should consider it a automatic dependency or not
+           if(Pkg.Section() && ConfigValueInSubTree("APT::Never-MarkAuto-Sections", Pkg.Section()))
+           {
+              if(DebugAutoInstall == true)
+                 std::clog << OutputInDepth(Depth) << "Setting NOT as auto-installed (direct "
+                            << Start.DepType() << " of pkg in APT::Never-MarkAuto-Sections)" << std::endl;
+              MarkInstall(InstPkg,true,Depth + 1, true);
+           }
+           else 
+           {
+              // mark automatic dependency
+              MarkInstall(InstPkg,true,Depth + 1, false, ForceImportantDeps);
+              // Set the autoflag, after MarkInstall because MarkInstall unsets it
+              if (P->CurrentVer == 0)
+                 PkgState[InstPkg->ID].Flags |= Flag::Auto;
+           }
         }
-        
         continue;
       }
-      
+
       /* For conflicts we just de-install the package and mark as auto,
-         Conflicts may not have or groups */
-      if (Start->Type == Dep::Conflicts || Start->Type == Dep::Obsoletes)
+         Conflicts may not have or groups.  For dpkg's Breaks we try to
+         upgrade the package. */
+      if (Start->Type == Dep::Conflicts || Start->Type == Dep::Obsoletes ||
+         Start->Type == Dep::DpkgBreaks)
       {
         for (Version **I = List; *I != 0; I++)
         {
            VerIterator Ver(*this,*I);
            PkgIterator Pkg = Ver.ParentPkg();
-      
-           MarkDelete(Pkg);
-           PkgState[Pkg->ID].Flags |= Flag::Auto;
+
+           if (Start->Type != Dep::DpkgBreaks)
+              MarkDelete(Pkg,false,Depth + 1, false);
+           else if (PkgState[Pkg->ID].CandidateVer != *I)
+              MarkInstall(Pkg,true,Depth + 1, false, ForceImportantDeps);
         }
         continue;
       }      
    }
 }
                                                                        /*}}}*/
+// DepCache::IsInstallOk - check if it is ok to install this package   /*{{{*/
+// ---------------------------------------------------------------------
+/* The default implementation just honors dpkg hold
+   But an application using this library can override this method
+   to control the MarkInstall behaviour */
+bool pkgDepCache::IsInstallOk(PkgIterator const &Pkg,bool AutoInst,
+                             unsigned long Depth, bool FromUser)
+{
+   if (FromUser == false && Pkg->SelectedState == pkgCache::State::Hold && _config->FindB("APT::Ignore-Hold",false) == false)
+   {
+      if (DebugMarker == true)
+        std::clog << OutputInDepth(Depth) << "Hold prevents MarkInstall of " << Pkg << " FU=" << FromUser << std::endl;
+      return false;
+   }
+   return true;
+}
+                                                                       /*}}}*/
 // DepCache::SetReInstall - Set the reinstallation flag                        /*{{{*/
 // ---------------------------------------------------------------------
 /* */
 void pkgDepCache::SetReInstall(PkgIterator const &Pkg,bool To)
 {
+   ActionGroup group(*this);
+
    RemoveSizes(Pkg);
    RemoveStates(Pkg);
    
@@ -765,9 +1356,11 @@ void pkgDepCache::SetReInstall(PkgIterator const &Pkg,bool To)
 /* */
 void pkgDepCache::SetCandidateVersion(VerIterator TargetVer)
 {
+   ActionGroup group(*this);
+
    pkgCache::PkgIterator Pkg = TargetVer.ParentPkg();
    StateCache &P = PkgState[Pkg->ID];
-   
+
    RemoveSizes(Pkg);
    RemoveStates(Pkg);
 
@@ -780,6 +1373,18 @@ void pkgDepCache::SetCandidateVersion(VerIterator TargetVer)
    Update(Pkg);
    AddSizes(Pkg);
 }
+
+void pkgDepCache::MarkAuto(const PkgIterator &Pkg, bool Auto)
+{
+  StateCache &state = PkgState[Pkg->ID];
+
+  ActionGroup group(*this);
+
+  if(Auto)
+    state.Flags |= Flag::Auto;
+  else
+    state.Flags &= ~Flag::Auto;
+}
                                                                        /*}}}*/
 // StateCache::Update - Compute the various static display things      /*{{{*/
 // ---------------------------------------------------------------------
@@ -825,7 +1430,6 @@ const char *pkgDepCache::StateCache::StripEpoch(const char *Ver)
    return Ver;
 }
                                                                        /*}}}*/
-
 // Policy::GetCandidateVer - Returns the Candidate install version     /*{{{*/
 // ---------------------------------------------------------------------
 /* The default just returns the highest available version that is not
@@ -869,11 +1473,309 @@ bool pkgDepCache::Policy::IsImportantDep(DepIterator Dep)
 {
    if(Dep.IsCritical())
       return true;
-   else if(Dep->Type == pkgCache::Dep::Recommends)
-      return  _config->FindB("APT::Install-Recommends", false);
+   else if(Dep->Type == pkgCache::Dep::Recommends) 
+   {
+      if ( _config->FindB("APT::Install-Recommends", false))
+        return true;
+      // we suport a special mode to only install-recommends for certain
+      // sections
+      // FIXME: this is a meant as a temporarly solution until the 
+      //        recommends are cleaned up
+      const char *sec = Dep.ParentVer().Section();
+      if (sec && ConfigValueInSubTree("APT::Install-Recommends-Sections", sec))
+        return true;
+   }
    else if(Dep->Type == pkgCache::Dep::Suggests)
      return _config->FindB("APT::Install-Suggests", false);
 
    return false;
 }
                                                                        /*}}}*/
+pkgDepCache::DefaultRootSetFunc::DefaultRootSetFunc()                  /*{{{*/
+  : constructedSuccessfully(false)
+{
+  Configuration::Item const *Opts;
+  Opts = _config->Tree("APT::NeverAutoRemove");
+  if (Opts != 0 && Opts->Child != 0)
+    {
+      Opts = Opts->Child;
+      for (; Opts != 0; Opts = Opts->Next)
+       {
+         if (Opts->Value.empty() == true)
+           continue;
+
+         regex_t *p = new regex_t;
+         if(regcomp(p,Opts->Value.c_str(),
+                    REG_EXTENDED | REG_ICASE | REG_NOSUB) != 0)
+           {
+             regfree(p);
+             delete p;
+             _error->Error("Regex compilation error for APT::NeverAutoRemove");
+             return;
+           }
+
+         rootSetRegexp.push_back(p);
+       }
+    }
+
+  constructedSuccessfully = true;
+}
+                                                                       /*}}}*/
+pkgDepCache::DefaultRootSetFunc::~DefaultRootSetFunc()                 /*{{{*/
+{
+  for(unsigned int i = 0; i < rootSetRegexp.size(); i++)
+    {
+      regfree(rootSetRegexp[i]);
+      delete rootSetRegexp[i];
+    }
+}
+                                                                       /*}}}*/
+bool pkgDepCache::DefaultRootSetFunc::InRootSet(const pkgCache::PkgIterator &pkg) /*{{{*/
+{
+   for(unsigned int i = 0; i < rootSetRegexp.size(); i++)
+      if (regexec(rootSetRegexp[i], pkg.Name(), 0, 0, 0) == 0)
+        return true;
+
+   return false;
+}
+                                                                       /*}}}*/
+pkgDepCache::InRootSetFunc *pkgDepCache::GetRootSetFunc()              /*{{{*/
+{
+  DefaultRootSetFunc *f = new DefaultRootSetFunc;
+  if(f->wasConstructedSuccessfully())
+    return f;
+  else
+    {
+      delete f;
+      return NULL;
+    }
+}
+                                                                       /*}}}*/
+bool pkgDepCache::MarkFollowsRecommends()
+{
+  return _config->FindB("APT::AutoRemove::RecommendsImportant", true);
+}
+
+bool pkgDepCache::MarkFollowsSuggests()
+{
+  return _config->FindB("APT::AutoRemove::SuggestsImportant", false);
+}
+
+// pkgDepCache::MarkRequired - the main mark algorithm                 /*{{{*/
+bool pkgDepCache::MarkRequired(InRootSetFunc &userFunc)
+{
+   bool follow_recommends;
+   bool follow_suggests;
+   bool debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
+
+   // init the states
+   for(PkgIterator p = PkgBegin(); !p.end(); ++p)
+   {
+      PkgState[p->ID].Marked  = false;
+      PkgState[p->ID].Garbage = false;
+
+      // debug output
+      if(debug_autoremove && PkgState[p->ID].Flags & Flag::Auto)
+        std::clog << "AutoDep: " << p.FullName() << std::endl;
+   }
+
+   // init vars
+   follow_recommends = MarkFollowsRecommends();
+   follow_suggests   = MarkFollowsSuggests();
+
+
+
+   // do the mark part, this is the core bit of the algorithm
+   for(PkgIterator p = PkgBegin(); !p.end(); ++p)
+   {
+      if(!(PkgState[p->ID].Flags & Flag::Auto) ||
+         (p->Flags & Flag::Essential) ||
+         userFunc.InRootSet(p))
+          
+      {
+        // the package is installed (and set to keep)
+        if(PkgState[p->ID].Keep() && !p.CurrentVer().end())
+           MarkPackage(p, p.CurrentVer(),
+                       follow_recommends, follow_suggests);
+        // the package is to be installed 
+        else if(PkgState[p->ID].Install())
+           MarkPackage(p, PkgState[p->ID].InstVerIter(*this),
+                       follow_recommends, follow_suggests);
+      }
+   }
+
+   return true;
+}
+                                                                       /*}}}*/
+// MarkPackage - mark a single package in Mark-and-Sweep               /*{{{*/
+void pkgDepCache::MarkPackage(const pkgCache::PkgIterator &pkg,
+                             const pkgCache::VerIterator &ver,
+                             bool const &follow_recommends,
+                             bool const &follow_suggests)
+{
+   pkgDepCache::StateCache &state = PkgState[pkg->ID];
+
+   // if we are marked already we are done
+   if(state.Marked)
+      return;
+
+   VerIterator const currver = pkg.CurrentVer();
+   VerIterator const candver = state.CandidateVerIter(*this);
+   VerIterator const instver = state.InstVerIter(*this);
+
+#if 0
+   // If a package was garbage-collected but is now being marked, we
+   // should re-select it 
+   // For cases when a pkg is set to upgrade and this trigger the
+   // removal of a no-longer used dependency.  if the pkg is set to
+   // keep again later it will result in broken deps
+   if(state.Delete() && state.RemoveReason = Unused) 
+   {
+      if(ver==candver)
+        mark_install(pkg, false, false, NULL);
+      else if(ver==pkg.CurrentVer())
+        MarkKeep(pkg, false, false);
+      
+      instver=state.InstVerIter(*this);
+   }
+#endif
+
+   // For packages that are not going to be removed, ignore versions
+   // other than the InstVer.  For packages that are going to be
+   // removed, ignore versions other than the current version.
+   if(!(ver == instver && !instver.end()) &&
+      !(ver == currver && instver.end() && !ver.end()))
+      return;
+
+   bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove", false);
+
+   if(debug_autoremove)
+     {
+       std::clog << "Marking: " << pkg.FullName();
+       if(!ver.end())
+        std::clog << " " << ver.VerStr();
+       if(!currver.end())
+        std::clog << ", Curr=" << currver.VerStr();
+       if(!instver.end())
+        std::clog << ", Inst=" << instver.VerStr();
+       std::clog << std::endl;
+     }
+
+   state.Marked=true;
+
+   if(ver.end() == true)
+      return;
+
+   // If the version belongs to a Multi-Arch all package
+   // we will mark all others in this Group with this version also
+   // Beware: We compare versions here the lazy way: string comparision
+   // this is bad if multiple repositories provide different versions
+   // of the package with an identical version number - but even in this
+   // case the dependencies are likely the same.
+   if (ver->MultiArch == pkgCache::Version::All &&
+       strcmp(ver.Arch(true), "all") == 0)
+   {
+      GrpIterator G = pkg.Group();
+      const char* const VerStr = ver.VerStr();
+      for (PkgIterator P = G.FindPkg("any");
+          P.end() != true; P = G.NextPkg(P))
+      {
+        for (VerIterator V = P.VersionList();
+             V.end() != true; ++V)
+        {
+           if (strcmp(VerStr, V.VerStr()) != 0)
+              continue;
+           MarkPackage(P, V, follow_recommends, follow_suggests);
+           break;
+        }
+      }
+   }
+
+     for(DepIterator d = ver.DependsList(); !d.end(); ++d)
+     {
+       if(d->Type == Dep::Depends ||
+          d->Type == Dep::PreDepends ||
+          (follow_recommends &&
+           d->Type == Dep::Recommends) ||
+          (follow_suggests &&
+           d->Type == Dep::Suggests))
+        {
+          // Try all versions of this package.
+          for(VerIterator V = d.TargetPkg().VersionList(); 
+              !V.end(); ++V)
+          {
+             if(_system->VS->CheckDep(V.VerStr(), d->CompareOp, d.TargetVer()))
+             {
+               if(debug_autoremove)
+                 {
+                   std::clog << "Following dep: " << d.ParentPkg().FullName()
+                             << " " << d.ParentVer().VerStr() << " "
+                             << d.DepType() << " " << d.TargetPkg().FullName();
+                   if((d->CompareOp & ~pkgCache::Dep::Or) != pkgCache::Dep::NoOp)
+                     {
+                       std::clog << " (" << d.CompType() << " "
+                                 << d.TargetVer() << ")";
+                     }
+                   std::clog << std::endl;
+                 }
+                MarkPackage(V.ParentPkg(), V,
+                            follow_recommends, follow_suggests);
+             }
+          }
+          // Now try virtual packages
+          for(PrvIterator prv=d.TargetPkg().ProvidesList(); 
+              !prv.end(); ++prv)
+          {
+             if(_system->VS->CheckDep(prv.ProvideVersion(), d->CompareOp, 
+                                      d.TargetVer()))
+             {
+               if(debug_autoremove)
+                 {
+                   std::clog << "Following dep: " << d.ParentPkg().FullName() << " "
+                             << d.ParentVer().VerStr() << " "
+                             << d.DepType() << " " << d.TargetPkg().FullName() << " ";
+                   if((d->CompareOp & ~pkgCache::Dep::Or) != pkgCache::Dep::NoOp)
+                     {
+                       std::clog << " (" << d.CompType() << " "
+                                 << d.TargetVer() << ")";
+                     }
+                   std::clog << ", provided by "
+                             << prv.OwnerPkg().FullName() << " "
+                             << prv.OwnerVer().VerStr()
+                             << std::endl;
+                 }
+
+                MarkPackage(prv.OwnerPkg(), prv.OwnerVer(),
+                            follow_recommends, follow_suggests);
+             }
+          }
+       }
+     }
+}
+                                                                       /*}}}*/
+bool pkgDepCache::Sweep()                                              /*{{{*/
+{
+   bool debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
+
+   // do the sweep
+   for(PkgIterator p=PkgBegin(); !p.end(); ++p)
+   {
+     StateCache &state=PkgState[p->ID];
+
+     // skip required packages
+     if (!p.CurrentVer().end() && 
+        (p.CurrentVer()->Priority == pkgCache::State::Required))
+       continue;
+
+     // if it is not marked and it is installed, it's garbage 
+     if(!state.Marked && (!p.CurrentVer().end() || state.Install()))
+     {
+       state.Garbage=true;
+       if(debug_autoremove)
+          std::cout << "Garbage: " << p.FullName() << std::endl;
+     }
+  }   
+
+   return true;
+}
+                                                                       /*}}}*/