+// ProblemResolver::InstallProtect - Install all protected packages    /*{{{*/
+// ---------------------------------------------------------------------
+/* This is used to make sure protected packages are installed */
+void pkgProblemResolver::InstallProtect()
+{
+   pkgDepCache::ActionGroup group(Cache);
+
+   for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
+   {
+      if ((Flags[I->ID] & Protected) == Protected)
+      {
+        if ((Flags[I->ID] & ToRemove) == ToRemove)
+           Cache.MarkDelete(I);
+        else 
+        {
+           // preserve the information whether the package was auto
+           // or manually installed
+           bool autoInst = (Cache[I].Flags & pkgCache::Flag::Auto);
+           Cache.MarkInstall(I, false, 0, !autoInst);
+        }
+      }
+   }   
+}
+                                                                       /*}}}*/
+// PrioSortList - Sort a list of versions by priority                  /*{{{*/
+// ---------------------------------------------------------------------
+/* 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);
+}
+                                                                       /*}}}*/
+// 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;
+   if (Fetcher.Setup(&Stat, _config->FindDir("Dir::State::Lists")) == false)
+      return false;
+
+   // 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;
+      }
+
+      Failed = true;
+   }
+   
+   // 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."));
+
+
+   // Run the success scripts if all was fine
+   if(!TransientNetworkFailure && !Failed)
+      RunScripts("APT::Update::Post-Invoke-Success");
+
+   // Run the other scripts
+   RunScripts("APT::Update::Post-Invoke");
+   return true;
+}
+                                                                       /*}}}*/