Adding upstream version 2.7.12.upstream/2.7.12

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1195 insertions, 0 deletions

diff --git a/apt-pkg/edsp.cc b/apt-pkg/edsp.cc
new file mode 100644
index 0000000..b0ac4ae
--- /dev/null
+++ b/apt-pkg/edsp.cc
@@ -0,0 +1,1195 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+   Set of methods to help writing and reading everything needed for EDSP
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/algorithms.h>
+#include <apt-pkg/aptconfiguration.h>
+#include <apt-pkg/cacheset.h>
+#include <apt-pkg/depcache.h>
+#include <apt-pkg/edsp.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/packagemanager.h>
+#include <apt-pkg/pkgcache.h>
+#include <apt-pkg/pkgsystem.h>
+#include <apt-pkg/prettyprinters.h>
+#include <apt-pkg/progress.h>
+#include <apt-pkg/string_view.h>
+#include <apt-pkg/strutl.h>
+#include <apt-pkg/tagfile.h>
+
+#include <cctype>
+#include <cstddef>
+#include <cstdio>
+#include <cstring>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <algorithm>
+#include <array>
+#include <limits>
+#include <sstream>
+#include <string>
+
+#include <apti18n.h>
+									/*}}}*/
+
+using std::string;
+
+// we could use pkgCache::DepType and ::Priority, but these would be localized strings…
+constexpr char const * const PrioMap[] = {
+   nullptr, "important", "required", "standard",
+   "optional", "extra"
+};
+constexpr char const * const DepMap[] = {
+   nullptr, "Depends", "Pre-Depends", "Suggests",
+   "Recommends" , "Conflicts", "Replaces",
+   "Obsoletes", "Breaks", "Enhances"
+};
+
+// WriteOkay - varaidic helper to easily Write to a FileFd		/*{{{*/
+static bool WriteOkay_fn(FileFd &) { return true; }
+template<typename... Tail> static bool WriteOkay_fn(FileFd &output, APT::StringView data, Tail... more_data)
+{
+   return likely(output.Write(data.data(), data.length()) && WriteOkay_fn(output, more_data...));
+}
+template<typename... Tail> static bool WriteOkay_fn(FileFd &output, unsigned int data, Tail... more_data)
+{
+   std::string number;
+   strprintf(number, "%d", data);
+   return likely(output.Write(number.data(), number.length()) && WriteOkay_fn(output, more_data...));
+}
+template<typename... Data> static bool WriteOkay(bool &Okay, FileFd &output, Data&&... data)
+{
+   Okay = likely(Okay && WriteOkay_fn(output, std::forward<Data>(data)...));
+   return Okay;
+}
+template<typename... Data> static bool WriteOkay(FileFd &output, Data&&... data)
+{
+   bool Okay = likely(output.Failed() == false);
+   return WriteOkay(Okay, output, std::forward<Data>(data)...);
+}
+									/*}}}*/
+// WriteScenarioVersion							/*{{{*/
+static bool WriteScenarioVersion(FileFd &output, pkgCache::PkgIterator const &Pkg,
+				pkgCache::VerIterator const &Ver)
+{
+   bool Okay = WriteOkay(output, "Package: ", Pkg.Name(),
+	 "\nArchitecture: ", Ver.Arch(),
+	 "\nVersion: ", Ver.VerStr());
+   WriteOkay(Okay, output, "\nAPT-ID: ", Ver->ID);
+   if (Ver.PhasedUpdatePercentage() != 100)
+      WriteOkay(Okay, output, "\nPhased-Update-Percentage: ", Ver.PhasedUpdatePercentage());
+   if ((Pkg->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
+      WriteOkay(Okay, output, "\nEssential: yes");
+   if ((Ver->MultiArch & pkgCache::Version::Allowed) == pkgCache::Version::Allowed)
+      WriteOkay(Okay, output, "\nMulti-Arch: allowed");
+   else if ((Ver->MultiArch & pkgCache::Version::Foreign) == pkgCache::Version::Foreign)
+      WriteOkay(Okay, output, "\nMulti-Arch: foreign");
+   else if ((Ver->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
+      WriteOkay(Okay, output, "\nMulti-Arch: same");
+   return Okay;
+}
+									/*}}}*/
+// WriteScenarioDependency						/*{{{*/
+static bool WriteScenarioDependency(FileFd &output, pkgCache::VerIterator const &Ver, bool const OnlyCritical)
+{
+   std::array<std::string, APT_ARRAY_SIZE(DepMap)> dependencies;
+   bool orGroup = false;
+   for (pkgCache::DepIterator Dep = Ver.DependsList(); Dep.end() == false; ++Dep)
+   {
+      if (Dep.IsImplicit() == true)
+	 continue;
+      if (OnlyCritical && Dep.IsCritical() == false)
+	 continue;
+      if (orGroup == false && dependencies[Dep->Type].empty() == false)
+	 dependencies[Dep->Type].append(", ");
+      dependencies[Dep->Type].append(Dep.TargetPkg().Name());
+      if (Dep->Version != 0)
+	 dependencies[Dep->Type].append(" (").append(pkgCache::CompTypeDeb(Dep->CompareOp)).append(" ").append(Dep.TargetVer()).append(")");
+      if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
+      {
+	 dependencies[Dep->Type].append(" | ");
+	 orGroup = true;
+      }
+      else
+	 orGroup = false;
+   }
+   bool Okay = output.Failed() == false;
+   for (size_t i = 1; i < dependencies.size(); ++i)
+      if (dependencies[i].empty() == false)
+	 WriteOkay(Okay, output, "\n", DepMap[i], ": ", dependencies[i]);
+   std::vector<std::string> provides;
+   for (auto Prv = Ver.ProvidesList(); not Prv.end(); ++Prv)
+   {
+      if (Prv.IsMultiArchImplicit())
+	 continue;
+      std::string provide = Prv.Name();
+      if (Prv->ProvideVersion != 0)
+	 provide.append(" (= ").append(Prv.ProvideVersion()).append(")");
+      if ((Ver->MultiArch & pkgCache::Version::Foreign) != 0 && std::find(provides.cbegin(), provides.cend(), provide) != provides.cend())
+	 continue;
+      provides.emplace_back(std::move(provide));
+   }
+   if (not provides.empty())
+   {
+      std::ostringstream out;
+      std::copy(provides.begin(), provides.end() - 1, std::ostream_iterator<std::string>(out, ", "));
+      out << provides.back();
+      WriteOkay(Okay, output, "\nProvides: ", out.str());
+   }
+   return WriteOkay(Okay, output, "\n");
+}
+									/*}}}*/
+// WriteScenarioLimitedDependency					/*{{{*/
+static bool WriteScenarioLimitedDependency(FileFd &output,
+					  pkgCache::VerIterator const &Ver,
+					  std::vector<bool> const &pkgset,
+					  bool const OnlyCritical)
+{
+   std::array<std::string, APT_ARRAY_SIZE(DepMap)> dependencies;
+   bool orGroup = false;
+   for (pkgCache::DepIterator Dep = Ver.DependsList(); Dep.end() == false; ++Dep)
+   {
+      if (Dep.IsImplicit() == true)
+	 continue;
+      if (OnlyCritical && Dep.IsCritical() == false)
+	 continue;
+      if (orGroup == false)
+      {
+	 if (pkgset[Dep.TargetPkg()->ID] == false)
+	    continue;
+	 if (dependencies[Dep->Type].empty() == false)
+	    dependencies[Dep->Type].append(", ");
+      }
+      else if (pkgset[Dep.TargetPkg()->ID] == false)
+      {
+	 if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
+	    continue;
+	 dependencies[Dep->Type].erase(dependencies[Dep->Type].end()-3, dependencies[Dep->Type].end());
+	 orGroup = false;
+	 continue;
+      }
+      dependencies[Dep->Type].append(Dep.TargetPkg().Name());
+      if (Dep->Version != 0)
+	 dependencies[Dep->Type].append(" (").append(pkgCache::CompTypeDeb(Dep->CompareOp)).append(" ").append(Dep.TargetVer()).append(")");
+      if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
+      {
+	 dependencies[Dep->Type].append(" | ");
+	 orGroup = true;
+      }
+      else
+	 orGroup = false;
+   }
+   bool Okay = output.Failed() == false;
+   for (size_t i = 1; i < dependencies.size(); ++i)
+      if (dependencies[i].empty() == false)
+	 WriteOkay(Okay, output, "\n", DepMap[i], ": ", dependencies[i]);
+   string provides;
+   for (pkgCache::PrvIterator Prv = Ver.ProvidesList(); Prv.end() == false; ++Prv)
+   {
+      if (Prv.IsMultiArchImplicit() == true)
+	 continue;
+      if (pkgset[Prv.ParentPkg()->ID] == false)
+	 continue;
+      if (provides.empty() == false)
+	 provides.append(", ");
+      provides.append(Prv.Name());
+      if (Prv->ProvideVersion != 0)
+	 provides.append(" (= ").append(Prv.ProvideVersion()).append(")");
+   }
+   if (provides.empty() == false)
+      WriteOkay(Okay, output, "\nProvides: ", provides);
+   return WriteOkay(Okay, output, "\n");
+}
+									/*}}}*/
+static bool checkKnownArchitecture(std::string const &arch)		/*{{{*/
+{
+   if (APT::Configuration::checkArchitecture(arch))
+      return true;
+   static auto const veryforeign = _config->FindVector("APT::BarbarianArchitectures");
+   return std::find(veryforeign.begin(), veryforeign.end(), arch) != veryforeign.end();
+}
+									/*}}}*/
+static bool WriteGenericRequestHeaders(FileFd &output, APT::StringView const head)/*{{{*/
+{
+   bool Okay = WriteOkay(output, head, "Architecture: ", _config->Find("APT::Architecture"), "\n",
+	 "Architectures:");
+   for (auto const &a : APT::Configuration::getArchitectures())
+       WriteOkay(Okay, output, " ", a);
+   for (auto const &a : _config->FindVector("APT::BarbarianArchitectures"))
+       WriteOkay(Okay, output, " ", a);
+   return WriteOkay(Okay, output, "\n");
+}
+									/*}}}*/
+static bool SkipUnavailableVersions(pkgDepCache &Cache, pkgCache::PkgIterator const &Pkg, pkgCache::VerIterator const &Ver)/*{{{*/
+{
+   /* versions which aren't current and aren't available in
+      any "online" source file are bad, expect if they are the chosen
+      candidate: The exception is for build-dep implementation as it creates
+      such pseudo (package) versions and removes them later on again.
+      We filter out versions at all so packages in 'rc' state only available
+      in dpkg/status aren't passed to solvers as they can't be installed. */
+   if (Pkg->CurrentVer != 0)
+      return false;
+   if (Cache.GetCandidateVersion(Pkg) == Ver)
+      return false;
+   for (pkgCache::VerFileIterator I = Ver.FileList(); I.end() == false; ++I)
+      if (I.File().Flagged(pkgCache::Flag::NotSource) == false)
+	 return false;
+   return true;
+}
+									/*}}}*/
+static bool WriteScenarioEDSPVersion(pkgDepCache &Cache, FileFd &output, pkgCache::PkgIterator const &Pkg,/*{{{*/
+				pkgCache::VerIterator const &Ver)
+{
+   bool Okay = WriteOkay(output, "\nSource: ", Ver.SourcePkgName(),
+	 "\nSource-Version: ", Ver.SourceVerStr());
+   if (PrioMap[Ver->Priority] != nullptr)
+      WriteOkay(Okay, output, "\nPriority: ", PrioMap[Ver->Priority]);
+   if (Ver->Section != 0)
+      WriteOkay(Okay, output, "\nSection: ", Ver.Section());
+   if (Pkg.CurrentVer() == Ver)
+      WriteOkay(Okay, output, "\nInstalled: yes");
+   if (Pkg->SelectedState == pkgCache::State::Hold ||
+       (Cache[Pkg].Keep() == true && Cache[Pkg].Protect() == true))
+      WriteOkay(Okay, output, "\nHold: yes");
+   std::set<string> Releases;
+   for (pkgCache::VerFileIterator I = Ver.FileList(); I.end() == false; ++I) {
+      pkgCache::PkgFileIterator File = I.File();
+      if (File.Flagged(pkgCache::Flag::NotSource) == false) {
+	 string Release = File.RelStr();
+	 if (!Release.empty())
+	    Releases.insert(Release);
+      }
+   }
+   if (!Releases.empty()) {
+       WriteOkay(Okay, output, "\nAPT-Release:");
+       for (std::set<string>::iterator R = Releases.begin(); R != Releases.end(); ++R)
+	   WriteOkay(Okay, output, "\n ", *R);
+   }
+   WriteOkay(Okay, output, "\nAPT-Pin: ", Cache.GetPolicy().GetPriority(Ver));
+   if (Cache.GetCandidateVersion(Pkg) == Ver)
+      WriteOkay(Okay, output, "\nAPT-Candidate: yes");
+   if ((Cache[Pkg].Flags & pkgCache::Flag::Auto) == pkgCache::Flag::Auto)
+      WriteOkay(Okay, output, "\nAPT-Automatic: yes");
+   return Okay;
+}
+									/*}}}*/
+// EDSP::WriteScenario - to the given file descriptor			/*{{{*/
+bool EDSP::WriteScenario(pkgDepCache &Cache, FileFd &output, OpProgress *Progress)
+{
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().VersionCount, _("Send scenario to solver"));
+   decltype(Cache.Head().VersionCount) p = 0;
+   bool Okay = output.Failed() == false;
+   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false && likely(Okay); ++Pkg)
+   {
+      if (Pkg->CurrentVer == 0 && not checkKnownArchitecture(Pkg.Arch()))
+	 continue;
+      for (pkgCache::VerIterator Ver = Pkg.VersionList(); Ver.end() == false && likely(Okay); ++Ver, ++p)
+      {
+	 if (SkipUnavailableVersions(Cache, Pkg, Ver))
+	    continue;
+	 Okay &= WriteScenarioVersion(output, Pkg, Ver);
+	 Okay &= WriteScenarioEDSPVersion(Cache, output, Pkg, Ver);
+	 Okay &= WriteScenarioDependency(output, Ver, false);
+	 WriteOkay(Okay, output, "\n");
+	 if (Progress != NULL && p % 100 == 0)
+	    Progress->Progress(p);
+      }
+   }
+   return Okay;
+}
+									/*}}}*/
+// EDSP::WriteLimitedScenario - to the given file descriptor		/*{{{*/
+bool EDSP::WriteLimitedScenario(pkgDepCache &Cache, FileFd &output,
+				std::vector<bool> const &pkgset,
+				OpProgress *Progress)
+{
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().VersionCount, _("Send scenario to solver"));
+   decltype(Cache.Head().PackageCount) p = 0;
+   bool Okay = output.Failed() == false;
+   for (auto Pkg = Cache.PkgBegin(); Pkg.end() == false && likely(Okay); ++Pkg, ++p)
+   {
+      if (pkgset[Pkg->ID] == false)
+	 continue;
+      for (pkgCache::VerIterator Ver = Pkg.VersionList(); Ver.end() == false && likely(Okay); ++Ver)
+      {
+	 if (SkipUnavailableVersions(Cache, Pkg, Ver))
+	    continue;
+	 Okay &= WriteScenarioVersion(output, Pkg, Ver);
+	 Okay &= WriteScenarioEDSPVersion(Cache, output, Pkg, Ver);
+	 Okay &= WriteScenarioLimitedDependency(output, Ver, pkgset, false);
+	 WriteOkay(Okay, output, "\n");
+	 if (Progress != NULL && p % 100 == 0)
+	    Progress->Progress(p);
+      }
+   }
+   if (Progress != NULL)
+      Progress->Done();
+   return Okay;
+}
+									/*}}}*/
+// EDSP::WriteRequest - to the given file descriptor			/*{{{*/
+bool EDSP::WriteRequest(pkgDepCache &Cache, FileFd &output,
+			unsigned int const flags,
+			OpProgress *Progress)
+{
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().PackageCount, _("Send request to solver"));
+   decltype(Cache.Head().PackageCount) p = 0;
+   string del, inst;
+   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg, ++p)
+   {
+      if (Progress != NULL && p % 100 == 0)
+         Progress->Progress(p);
+      string* req;
+      pkgDepCache::StateCache &P = Cache[Pkg];
+      if (P.Delete() == true)
+	 req = &del;
+      else if (P.NewInstall() == true || P.Upgrade() == true || P.ReInstall() == true ||
+	       (P.Mode == pkgDepCache::ModeKeep && (P.iFlags & pkgDepCache::Protected) == pkgDepCache::Protected))
+	 req = &inst;
+      else
+	 continue;
+      req->append(" ").append(Pkg.FullName());
+   }
+
+   bool Okay = WriteGenericRequestHeaders(output, "Request: EDSP 0.5\n");
+   string machineID = APT::Configuration::getMachineID();
+   if (not machineID.empty())
+      WriteOkay(Okay, output, "Machine-ID: ", machineID, "\n");
+   if (del.empty() == false)
+      WriteOkay(Okay, output, "Remove:", del, "\n");
+   if (inst.empty() == false)
+      WriteOkay(Okay, output, "Install:", inst, "\n");
+   if (flags & Request::AUTOREMOVE)
+      WriteOkay(Okay, output, "Autoremove: yes\n");
+   if (flags & Request::UPGRADE_ALL)
+   {
+      WriteOkay(Okay, output, "Upgrade-All: yes\n");
+      if (flags & (Request::FORBID_NEW_INSTALL | Request::FORBID_REMOVE))
+	 WriteOkay(Okay, output, "Upgrade: yes\n");
+      else
+	 WriteOkay(Okay, output, "Dist-Upgrade: yes\n");
+   }
+   if (flags & Request::FORBID_NEW_INSTALL)
+      WriteOkay(Okay, output, "Forbid-New-Install: yes\n");
+   if (flags & Request::FORBID_REMOVE)
+      WriteOkay(Okay, output, "Forbid-Remove: yes\n");
+   auto const solver = _config->Find("APT::Solver", "internal");
+   WriteOkay(Okay, output, "Solver: ", solver, "\n");
+   if (_config->FindB("APT::Solver::Strict-Pinning", true) == false)
+      WriteOkay(Okay, output, "Strict-Pinning: no\n");
+   string solverpref("APT::Solver::");
+   solverpref.append(solver).append("::Preferences");
+   if (_config->Exists(solverpref) == true)
+      WriteOkay(Okay, output, "Preferences: ", _config->Find(solverpref,""), "\n");
+   return WriteOkay(Okay, output, "\n");
+}
+									/*}}}*/
+// EDSP::ReadResponse - from the given file descriptor			/*{{{*/
+bool EDSP::ReadResponse(int const input, pkgDepCache &Cache, OpProgress *Progress) {
+	/* We build an map id to mmap offset here
+	   In theory we could use the offset as ID, but then VersionCount
+	   couldn't be used to create other versionmappings anymore and it
+	   would be too easy for a (buggy) solver to segfault APT… */
+	auto VersionCount = Cache.Head().VersionCount;
+	decltype(VersionCount) VerIdx[VersionCount];
+	for (pkgCache::PkgIterator P = Cache.PkgBegin(); P.end() == false; ++P) {
+		for (pkgCache::VerIterator V = P.VersionList(); V.end() == false; ++V)
+			VerIdx[V->ID] = V.Index();
+		Cache[P].Marked = true;
+		Cache[P].Garbage = false;
+	}
+
+	FileFd in;
+	in.OpenDescriptor(input, FileFd::ReadOnly, true);
+	pkgTagFile response(&in, 100);
+	pkgTagSection section;
+
+	std::set<decltype(Cache.PkgBegin()->ID)> seenOnce;
+	while (response.Step(section) == true) {
+		std::string type;
+		if (section.Exists("Install") == true)
+			type = "Install";
+		else if (section.Exists("Remove") == true)
+			type = "Remove";
+		else if (section.Exists("Progress") == true) {
+			if (Progress != NULL) {
+				string msg = section.FindS("Message");
+				if (msg.empty() == true)
+					msg = _("Prepare for receiving solution");
+				Progress->SubProgress(100, msg, section.FindI("Percentage", 0));
+			}
+			continue;
+		} else if (section.Exists("Error") == true) {
+			if (_error->PendingError()) {
+				if (Progress != nullptr)
+					Progress->Done();
+				Progress = nullptr;
+				_error->DumpErrors(std::cerr, GlobalError::DEBUG, false);
+			}
+			std::string msg = SubstVar(SubstVar(section.FindS("Message"), "\n .\n", "\n\n"), "\n ", "\n");
+			if (msg.empty() == true) {
+				msg = _("External solver failed without a proper error message");
+				_error->Error("%s", msg.c_str());
+			} else
+				_error->Error("External solver failed with: %s", msg.substr(0,msg.find('\n')).c_str());
+			if (Progress != nullptr)
+				Progress->Done();
+			std::cerr << "The solver encountered an error of type: " << section.FindS("Error") << std::endl;
+			std::cerr << "The following information might help you to understand what is wrong:" << std::endl;
+			std::cerr << msg << std::endl << std::endl;
+			return false;
+		} else if (section.Exists("Autoremove") == true)
+			type = "Autoremove";
+		else {
+			char const *Start, *End;
+			section.GetSection(Start, End);
+			_error->Warning("Encountered an unexpected section with %d fields: %s", section.Count(), std::string(Start, End).c_str());
+			continue;
+		}
+
+		decltype(VersionCount) const id = section.FindULL(type, VersionCount);
+		if (id == VersionCount) {
+			_error->Warning("Unable to parse %s request with id value '%s'!", type.c_str(), section.FindS(type.c_str()).c_str());
+			continue;
+		} else if (id > VersionCount) {
+			_error->Warning("ID value '%s' in %s request stanza is to high to refer to a known version!", section.FindS(type.c_str()).c_str(), type.c_str());
+			continue;
+		}
+
+		pkgCache::VerIterator Ver(Cache.GetCache(), Cache.GetCache().VerP + VerIdx[id]);
+		auto const Pkg = Ver.ParentPkg();
+		if (type == "Autoremove") {
+			Cache[Pkg].Marked = false;
+			Cache[Pkg].Garbage = true;
+		} else if (seenOnce.emplace(Pkg->ID).second == false) {
+			_error->Warning("Ignoring %s stanza received for package %s which already had a previous stanza effecting it!", type.c_str(), Pkg.FullName(false).c_str());
+		} else if (type == "Install") {
+			if (Pkg.CurrentVer() == Ver) {
+				_error->Warning("Ignoring Install stanza received for version %s of package %s which is already installed!",
+				      Ver.VerStr(), Pkg.FullName(false).c_str());
+			} else {
+				Cache.SetCandidateVersion(Ver);
+				Cache.MarkInstall(Pkg, false, 0, false);
+			}
+		} else if (type == "Remove") {
+			if (Pkg->CurrentVer == 0)
+				_error->Warning("Ignoring Remove stanza received for version %s of package %s which isn't installed!",
+				      Ver.VerStr(), Pkg.FullName(false).c_str());
+			else if (Pkg.CurrentVer() != Ver)
+				_error->Warning("Ignoring Remove stanza received for version %s of package %s which isn't the installed version %s!",
+				      Ver.VerStr(), Pkg.FullName(false).c_str(), Pkg.CurrentVer().VerStr());
+			else
+				Cache.MarkDelete(Ver.ParentPkg(), false);
+		}
+	}
+	return true;
+}
+									/*}}}*/
+// ReadLine - first line from the given file descriptor			/*{{{*/
+// ---------------------------------------------------------------------
+/* Little helper method to read a complete line into a string. Similar to
+   fgets but we need to use the low-level read() here as otherwise the
+   listparser will be confused later on as mixing of fgets and read isn't
+   a supported action according to the manpages and results are undefined */
+static bool ReadLine(int const input, std::string &line) {
+	char one;
+	ssize_t data = 0;
+	line.erase();
+	line.reserve(100);
+	while ((data = read(input, &one, sizeof(one))) != -1) {
+		if (data != 1)
+			continue;
+		if (one == '\n')
+			return true;
+		if (one == '\r')
+			continue;
+		if (line.empty() == true && isblank(one) != 0)
+			continue;
+		line += one;
+	}
+	return false;
+}
+									/*}}}*/
+// StringToBool - convert yes/no to bool				/*{{{*/
+// ---------------------------------------------------------------------
+/* we are not as lazy as we are in the global StringToBool as we really
+   only accept yes/no here */
+static bool localStringToBool(std::string answer, bool const defValue) {
+   std::transform(answer.begin(), answer.end(), answer.begin(), ::tolower);
+   if (answer == "yes")
+      return true;
+   else if (answer == "no")
+      return false;
+   else
+      _error->Warning("Value '%s' is not a boolean 'yes' or 'no'!", answer.c_str());
+   return defValue;
+}
+									/*}}}*/
+static bool LineStartsWithAndStrip(std::string &line, APT::StringView const with)/*{{{*/
+{
+   if (line.compare(0, with.size(), with.data()) != 0)
+      return false;
+   line = APT::String::Strip(line.substr(with.length()));
+   return true;
+}
+									/*}}}*/
+static bool ReadFlag(unsigned int &flags, std::string &line, APT::StringView const name, unsigned int const setflag)/*{{{*/
+{
+   if (LineStartsWithAndStrip(line, name) == false)
+      return false;
+   if (localStringToBool(line, false))
+      flags |= setflag;
+   else
+      flags &= ~setflag;
+   return true;
+}
+									/*}}}*/
+// EDSP::ReadRequest - first stanza from the given file descriptor	/*{{{*/
+bool EDSP::ReadRequest(int const input, std::list<std::string> &install,
+			std::list<std::string> &remove, unsigned int &flags)
+{
+   install.clear();
+   remove.clear();
+   flags = 0;
+   std::string line;
+   while (ReadLine(input, line) == true)
+   {
+      // Skip empty lines before request
+      if (line.empty() == true)
+	 continue;
+      // The first Tag must be a request, so search for it
+      if (LineStartsWithAndStrip(line, "Request:"))
+	 continue;
+
+      while (ReadLine(input, line) == true)
+      {
+	 // empty lines are the end of the request
+	 if (line.empty() == true)
+	    return true;
+
+	 std::list<std::string> *request = NULL;
+	 if (LineStartsWithAndStrip(line, "Install:"))
+	    request = &install;
+	 else if (LineStartsWithAndStrip(line, "Remove:"))
+	    request = &remove;
+	 else if (ReadFlag(flags, line, "Upgrade:", (Request::UPGRADE_ALL | Request::FORBID_REMOVE | Request::FORBID_NEW_INSTALL)) ||
+	       ReadFlag(flags, line, "Dist-Upgrade:", Request::UPGRADE_ALL) ||
+	       ReadFlag(flags, line, "Upgrade-All:", Request::UPGRADE_ALL) ||
+	       ReadFlag(flags, line, "Forbid-New-Install:", Request::FORBID_NEW_INSTALL) ||
+	       ReadFlag(flags, line, "Forbid-Remove:", Request::FORBID_REMOVE) ||
+	       ReadFlag(flags, line, "Autoremove:", Request::AUTOREMOVE))
+	    ;
+	 else if (LineStartsWithAndStrip(line, "Architecture:"))
+	    _config->Set("APT::Architecture", line);
+	 else if (LineStartsWithAndStrip(line, "Architectures:"))
+	    _config->Set("APT::Architectures", SubstVar(line, " ", ","));
+	 else if (LineStartsWithAndStrip(line, "Machine-ID"))
+	    _config->Set("APT::Machine-ID", line);
+	 else if (LineStartsWithAndStrip(line, "Solver:"))
+	    ; // purely informational line
+	 else
+	    _error->Warning("Unknown line in EDSP Request stanza: %s", line.c_str());
+
+	 if (request == NULL)
+	    continue;
+	 auto const pkgs = VectorizeString(line, ' ');
+	 std::move(pkgs.begin(), pkgs.end(), std::back_inserter(*request));
+      }
+   }
+   return false;
+}									/*}}}*/
+// EDSP::ApplyRequest - first stanza from the given file descriptor	/*{{{*/
+bool EDSP::ApplyRequest(std::list<std::string> const &install,
+			 std::list<std::string> const &remove,
+			 pkgDepCache &Cache)
+{
+	for (std::list<std::string>::const_iterator i = install.begin();
+	     i != install.end(); ++i) {
+		pkgCache::PkgIterator P = Cache.FindPkg(*i);
+		if (P.end() == true)
+			_error->Warning("Package %s is not known, so can't be installed", i->c_str());
+		else
+			Cache.MarkInstall(P, false);
+	}
+
+	for (std::list<std::string>::const_iterator i = remove.begin();
+	     i != remove.end(); ++i) {
+		pkgCache::PkgIterator P = Cache.FindPkg(*i);
+		if (P.end() == true)
+			_error->Warning("Package %s is not known, so can't be installed", i->c_str());
+		else
+			Cache.MarkDelete(P);
+	}
+	return true;
+}
+									/*}}}*/
+// EDSP::WriteSolutionStanza - to the given file descriptor		/*{{{*/
+bool EDSP::WriteSolutionStanza(FileFd &output, char const * const Type, pkgCache::VerIterator const &Ver)
+{
+   bool Okay = output.Failed() == false;
+   WriteOkay(Okay, output, Type, ": ", _system->GetVersionMapping(Ver->ID));
+   if (_config->FindB("Debug::EDSP::WriteSolution", false) == true)
+      WriteOkay(Okay, output, "\nPackage: ", Ver.ParentPkg().FullName(), "\nVersion: ", Ver.VerStr());
+   return WriteOkay(Okay, output, "\n\n");
+}
+									/*}}}*/
+// EDSP::WriteProgess - pulse to the given file descriptor		/*{{{*/
+bool EDSP::WriteProgress(unsigned short const percent, const char* const message, FileFd &output) {
+	return WriteOkay(output, "Progress: ", TimeRFC1123(time(NULL), true), "\n",
+	      "Percentage: ", percent, "\n",
+	      "Message: ", message, "\n\n") && output.Flush();
+}
+									/*}}}*/
+// EDSP::WriteError - format an error message to be send to file descriptor /*{{{*/
+static std::string formatMessage(std::string const &msg)
+{
+	return SubstVar(SubstVar(APT::String::Strip(msg), "\n\n", "\n.\n"), "\n", "\n ");
+}
+bool EDSP::WriteError(char const * const uuid, std::string const &message, FileFd &output) {
+	return WriteOkay(output, "Error: ", uuid, "\n",
+	      "Message: ", formatMessage(message),
+	      "\n\n");
+}
+									/*}}}*/
+static std::string findExecutable(std::vector<std::string> const &dirs, char const * const binary) {/*{{{*/
+	for (auto && dir : dirs) {
+		std::string const file = flCombine(dir, binary);
+		if (RealFileExists(file) == true)
+			return file;
+	}
+	return "";
+}
+									/*}}}*/
+static pid_t ExecuteExternal(char const* const type, char const * const binary, char const * const configdir, int * const solver_in, int * const solver_out) {/*{{{*/
+	auto const solverDirs = _config->FindVector(configdir);
+	auto const file = findExecutable(solverDirs, binary);
+	std::string dumper;
+	{
+		dumper = findExecutable(solverDirs, "apt-dump-solver");
+		if (dumper.empty())
+			dumper = findExecutable(solverDirs, "dump");
+	}
+
+	if (file.empty() == true)
+	{
+		_error->Error("Can't call external %s '%s' as it is not in a configured directory!", type, binary);
+		return 0;
+	}
+	int external[4] = {-1, -1, -1, -1};
+	if (pipe(external) != 0 || pipe(external + 2) != 0)
+	{
+		_error->Errno("Resolve", "Can't create needed IPC pipes for EDSP");
+		return 0;
+	}
+	for (int i = 0; i < 4; ++i)
+		SetCloseExec(external[i], true);
+
+	pid_t Solver = ExecFork();
+	if (Solver == 0) {
+		dup2(external[0], STDIN_FILENO);
+		dup2(external[3], STDOUT_FILENO);
+		auto const dumpfile = _config->FindFile((std::string("Dir::Log::") + type).c_str());
+		auto const dumpdir = flNotFile(dumpfile);
+		auto const runasuser = _config->Find(std::string("APT::") + type + "::" + binary + "::RunAsUser",
+		      _config->Find(std::string("APT::") + type + "::RunAsUser",
+			 _config->Find("APT::Sandbox::User")));
+		if (dumper.empty() || dumpfile.empty() || dumper == file || CreateAPTDirectoryIfNeeded(dumpdir, dumpdir) == false)
+		{
+		   _config->Set("APT::Sandbox::User", runasuser);
+		   DropPrivileges();
+		   char const * const calling[] = { file.c_str(), nullptr };
+		   execv(calling[0], const_cast<char**>(calling));
+		}
+		else
+		{
+		   char const * const calling[] = { dumper.c_str(), "--user", runasuser.c_str(), dumpfile.c_str(), file.c_str(), nullptr };
+		   execv(calling[0], const_cast<char**>(calling));
+		}
+		std::cerr << "Failed to execute " << type << " '" << binary << "'!" << std::endl;
+		_exit(100);
+	}
+	close(external[0]);
+	close(external[3]);
+
+	if (WaitFd(external[1], true, 5) == false)
+	{
+		_error->Errno("Resolve", "Timed out while Waiting on availability of %s stdin", type);
+		return 0;
+	}
+
+	*solver_in = external[1];
+	*solver_out = external[2];
+	return Solver;
+}
+									/*}}}*/
+// EDSP::ExecuteSolver - fork requested solver and setup ipc pipes	{{{*/
+pid_t EDSP::ExecuteSolver(const char* const solver, int * const solver_in, int * const solver_out, bool) {
+	return ExecuteExternal("solver", solver, "Dir::Bin::Solvers", solver_in, solver_out);
+}
+									/*}}}*/
+static bool CreateDumpFile(char const * const id, char const * const type, FileFd &output)/*{{{*/
+{
+	auto const dumpfile = _config->FindFile((std::string("Dir::Log::") + type).c_str());
+	if (dumpfile.empty())
+		return false;
+	auto const dumpdir = flNotFile(dumpfile);
+	_error->PushToStack();
+	bool errored_out = CreateAPTDirectoryIfNeeded(dumpdir, dumpdir) == false ||
+	   output.Open(dumpfile, FileFd::WriteOnly | FileFd::Exclusive | FileFd::Create, FileFd::Extension, 0644) == false;
+	std::vector<std::string> downgrademsgs;
+	while (_error->empty() == false)
+	{
+		std::string msg;
+		_error->PopMessage(msg);
+		downgrademsgs.emplace_back(std::move(msg));
+	}
+	_error->RevertToStack();
+	for (auto && msg : downgrademsgs)
+	   _error->Warning("%s", msg.c_str());
+	if (errored_out)
+		return _error->WarningE(id, _("Could not open file '%s'"), dumpfile.c_str());
+	return true;
+}
+									/*}}}*/
+// EDSP::ResolveExternal - resolve problems by asking external for help	{{{*/
+bool EDSP::ResolveExternal(const char* const solver, pkgDepCache &Cache,
+			 unsigned int const flags, OpProgress *Progress) {
+	if (strcmp(solver, "internal") == 0)
+	{
+		FileFd output;
+		bool Okay = CreateDumpFile("EDSP::Resolve", "solver", output);
+		Okay &= EDSP::WriteRequest(Cache, output, flags, nullptr);
+		return Okay && EDSP::WriteScenario(Cache, output, nullptr);
+	}
+	_error->PushToStack();
+	int solver_in, solver_out;
+	pid_t const solver_pid = ExecuteSolver(solver, &solver_in, &solver_out, true);
+	if (solver_pid == 0)
+		return false;
+
+	FileFd output;
+	if (output.OpenDescriptor(solver_in, FileFd::WriteOnly | FileFd::BufferedWrite, true) == false)
+		return _error->Errno("ResolveExternal", "Opening solver %s stdin on fd %d for writing failed", solver, solver_in);
+
+	bool Okay = output.Failed() == false;
+	if (Okay && Progress != NULL)
+		Progress->OverallProgress(0, 100, 5, _("Execute external solver"));
+	Okay &= EDSP::WriteRequest(Cache, output, flags, Progress);
+	if (Okay && Progress != NULL)
+		Progress->OverallProgress(5, 100, 20, _("Execute external solver"));
+	Okay &= EDSP::WriteScenario(Cache, output, Progress);
+	output.Close();
+
+	if (Okay && Progress != NULL)
+		Progress->OverallProgress(25, 100, 75, _("Execute external solver"));
+	bool const ret = EDSP::ReadResponse(solver_out, Cache, Progress);
+	_error->MergeWithStack();
+	if (ExecWait(solver_pid, solver))
+		return ret;
+	return false;
+}									/*}}}*/
+
+bool EIPP::OrderInstall(char const * const solver, pkgPackageManager * const PM,	/*{{{*/
+			 unsigned int const flags, OpProgress * const Progress)
+{
+   if (strcmp(solver, "internal") == 0)
+   {
+      FileFd output;
+      _error->PushToStack();
+      bool Okay = CreateDumpFile("EIPP::OrderInstall", "planner", output);
+      if (Okay == false && dynamic_cast<pkgSimulate*>(PM) != nullptr)
+      {
+	 _error->RevertToStack();
+	 return false;
+      }
+      _error->MergeWithStack();
+      Okay &= EIPP::WriteRequest(PM->Cache, output, flags, nullptr);
+      return Okay && EIPP::WriteScenario(PM->Cache, output, nullptr);
+   }
+   _error->PushToStack();
+   int solver_in, solver_out;
+   pid_t const solver_pid = ExecuteExternal("planner", solver, "Dir::Bin::Planners", &solver_in, &solver_out);
+   if (solver_pid == 0)
+      return false;
+
+   FileFd output;
+   if (output.OpenDescriptor(solver_in, FileFd::WriteOnly | FileFd::BufferedWrite, true) == false)
+      return _error->Errno("EIPP::OrderInstall", "Opening planner %s stdin on fd %d for writing failed", solver, solver_in);
+
+   bool Okay = output.Failed() == false;
+   if (Okay && Progress != NULL)
+      Progress->OverallProgress(0, 100, 5, _("Execute external planner"));
+   Okay &= EIPP::WriteRequest(PM->Cache, output, flags, Progress);
+   if (Okay && Progress != NULL)
+      Progress->OverallProgress(5, 100, 20, _("Execute external planner"));
+   Okay &= EIPP::WriteScenario(PM->Cache, output, Progress);
+   output.Close();
+
+   if (Okay)
+   {
+      if (Progress != nullptr)
+	 Progress->OverallProgress(25, 100, 75, _("Execute external planner"));
+
+      // we don't tell the external planners about boring things
+      for (auto Pkg = PM->Cache.PkgBegin(); Pkg.end() == false; ++Pkg)
+      {
+	 if (Pkg->CurrentState == pkgCache::State::ConfigFiles && PM->Cache[Pkg].Purge() == true)
+	    PM->Remove(Pkg, true);
+      }
+   }
+   bool const ret = EIPP::ReadResponse(solver_out, PM, Progress);
+   _error->MergeWithStack();
+   if (ExecWait(solver_pid, solver))
+      return ret;
+   return false;
+}
+									/*}}}*/
+bool EIPP::WriteRequest(pkgDepCache &Cache, FileFd &output,		/*{{{*/
+			unsigned int const flags,
+			OpProgress * const Progress)
+{
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().PackageCount, _("Send request to planner"));
+   decltype(Cache.Head().PackageCount) p = 0;
+   string del, inst, reinst;
+   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg, ++p)
+   {
+      if (Progress != NULL && p % 100 == 0)
+         Progress->Progress(p);
+      string* req;
+      pkgDepCache::StateCache &P = Cache[Pkg];
+      if (P.Purge() == true && Pkg->CurrentState == pkgCache::State::ConfigFiles)
+	 continue;
+      if (P.Delete() == true)
+	 req = &del;
+      else if (P.NewInstall() == true || P.Upgrade() == true || P.Downgrade() == true)
+	 req = &inst;
+      else if (P.ReInstall() == true)
+	 req = &reinst;
+      else
+	 continue;
+      req->append(" ").append(Pkg.FullName());
+   }
+
+   bool Okay = WriteGenericRequestHeaders(output, "Request: EIPP 0.1\n");
+   if (del.empty() == false)
+      WriteOkay(Okay, output, "Remove:", del, "\n");
+   if (inst.empty() == false)
+      WriteOkay(Okay, output, "Install:", inst, "\n");
+   if (reinst.empty() == false)
+      WriteOkay(Okay, output, "ReInstall:", reinst, "\n");
+   WriteOkay(Okay, output, "Planner: ", _config->Find("APT::Planner", "internal"), "\n");
+   if ((flags & Request::IMMEDIATE_CONFIGURATION_ALL) != 0)
+      WriteOkay(Okay, output, "Immediate-Configuration: yes\n");
+   else if ((flags & Request::NO_IMMEDIATE_CONFIGURATION) != 0)
+      WriteOkay(Okay, output, "Immediate-Configuration: no\n");
+   else if ((flags & Request::ALLOW_TEMPORARY_REMOVE_OF_ESSENTIALS) != 0)
+      WriteOkay(Okay, output, "Allow-Temporary-Remove-of-Essentials: yes\n");
+   return WriteOkay(Okay, output, "\n");
+}
+									/*}}}*/
+static bool WriteScenarioEIPPVersion(pkgDepCache &, FileFd &output, pkgCache::PkgIterator const &Pkg,/*{{{*/
+				pkgCache::VerIterator const &Ver)
+{
+   bool Okay = true;
+   if (Pkg.CurrentVer() == Ver)
+      switch (Pkg->CurrentState)
+      {
+	 case pkgCache::State::NotInstalled: WriteOkay(Okay, output, "\nStatus: not-installed"); break;
+	 case pkgCache::State::ConfigFiles: WriteOkay(Okay, output, "\nStatus: config-files"); break;
+	 case pkgCache::State::HalfInstalled: WriteOkay(Okay, output, "\nStatus: half-installed"); break;
+	 case pkgCache::State::UnPacked: WriteOkay(Okay, output, "\nStatus: unpacked"); break;
+	 case pkgCache::State::HalfConfigured: WriteOkay(Okay, output, "\nStatus: half-configured"); break;
+	 case pkgCache::State::TriggersAwaited: WriteOkay(Okay, output, "\nStatus: triggers-awaited"); break;
+	 case pkgCache::State::TriggersPending: WriteOkay(Okay, output, "\nStatus: triggers-pending"); break;
+	 case pkgCache::State::Installed: WriteOkay(Okay, output, "\nStatus: installed"); break;
+      }
+   return Okay;
+}
+									/*}}}*/
+// EIPP::WriteScenario - to the given file descriptor			/*{{{*/
+template<typename forVersion> void forAllInterestingVersions(pkgDepCache &Cache, pkgCache::PkgIterator const &Pkg, forVersion const &func)
+{
+   if (Pkg->CurrentState == pkgCache::State::NotInstalled)
+   {
+      auto P = Cache[Pkg];
+      if (P.Install() == false)
+	 return;
+      func(Pkg, P.InstVerIter(Cache));
+   }
+   else
+   {
+      if (Pkg->CurrentVer != 0)
+	 func(Pkg, Pkg.CurrentVer());
+      auto P = Cache[Pkg];
+      auto const V = P.InstVerIter(Cache);
+      if (P.Delete() == false && Pkg.CurrentVer() != V)
+	 func(Pkg, V);
+   }
+}
+
+bool EIPP::WriteScenario(pkgDepCache &Cache, FileFd &output, OpProgress * const Progress)
+{
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().PackageCount, _("Send scenario to planner"));
+   decltype(Cache.Head().PackageCount) p = 0;
+   bool Okay = output.Failed() == false;
+   std::vector<bool> pkgset(Cache.Head().PackageCount, false);
+   auto const MarkVersion = [&](pkgCache::PkgIterator const &Pkg, pkgCache::VerIterator const &Ver) {
+      pkgset[Pkg->ID] = true;
+      for (auto D = Ver.DependsList(); D.end() == false; ++D)
+      {
+	 if (D.IsCritical() == false)
+	    continue;
+	 auto const P = D.TargetPkg();
+	 for (auto Prv = P.ProvidesList(); Prv.end() == false; ++Prv)
+	 {
+	    auto const V = Prv.OwnerVer();
+	    auto const PV = V.ParentPkg();
+	    if (V == PV.CurrentVer() || V == Cache[PV].InstVerIter(Cache))
+	       pkgset[PV->ID] = true;
+	 }
+	 pkgset[P->ID] = true;
+	 if (strcmp(P.Arch(), "any") == 0)
+	 {
+	    APT::StringView const pkgname(P.Name());
+	    auto const idxColon = pkgname.find(':');
+	    if (idxColon != APT::StringView::npos)
+	    {
+	       pkgCache::PkgIterator PA;
+	       if (pkgname.substr(idxColon + 1) == "any")
+	       {
+		  auto const GA = Cache.FindGrp(pkgname.substr(0, idxColon).to_string());
+		  for (auto PA = GA.PackageList(); PA.end() == false; PA = GA.NextPkg(PA))
+		  {
+		     pkgset[PA->ID] = true;
+		  }
+	       }
+	       else
+	       {
+		  auto const PA = Cache.FindPkg(pkgname.to_string());
+		  if (PA.end() == false)
+		     pkgset[PA->ID] = true;
+	       }
+	    }
+	 }
+	 else
+	 {
+	    auto const PA = Cache.FindPkg(P.FullName(false), "any");
+	    if (PA.end() == false)
+	       pkgset[PA->ID] = true;
+	 }
+      }
+   };
+   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg)
+      forAllInterestingVersions(Cache, Pkg, MarkVersion);
+   auto const WriteVersion = [&](pkgCache::PkgIterator const &Pkg, pkgCache::VerIterator const &Ver) {
+      Okay &= WriteScenarioVersion(output, Pkg, Ver);
+      Okay &= WriteScenarioEIPPVersion(Cache, output, Pkg, Ver);
+      Okay &= WriteScenarioLimitedDependency(output, Ver, pkgset, true);
+      WriteOkay(Okay, output, "\n");
+      if (Progress != NULL && p % 100 == 0)
+	 Progress->Progress(p);
+   };
+   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false && likely(Okay); ++Pkg, ++p)
+   {
+      if (pkgset[Pkg->ID] == false || Pkg->VersionList == 0)
+	 continue;
+      forAllInterestingVersions(Cache, Pkg, WriteVersion);
+   }
+   return Okay;
+}
+									/*}}}*/
+// EIPP::ReadResponse - from the given file descriptor			/*{{{*/
+bool EIPP::ReadResponse(int const input, pkgPackageManager * const PM, OpProgress *Progress) {
+   /* We build an map id to mmap offset here
+      In theory we could use the offset as ID, but then VersionCount
+      couldn't be used to create other versionmappings anymore and it
+      would be too easy for a (buggy) solver to segfault APT… */
+   auto VersionCount = PM->Cache.Head().VersionCount;
+   decltype(VersionCount) VerIdx[VersionCount];
+   for (pkgCache::PkgIterator P = PM->Cache.PkgBegin(); P.end() == false; ++P) {
+      for (pkgCache::VerIterator V = P.VersionList(); V.end() == false; ++V)
+	 VerIdx[V->ID] = V.Index();
+   }
+
+   FileFd in;
+   in.OpenDescriptor(input, FileFd::ReadOnly);
+   pkgTagFile response(&in, 100);
+   pkgTagSection section;
+
+   while (response.Step(section) == true) {
+      char const * type = nullptr;
+      if (section.Exists("Progress") == true) {
+	 if (Progress != NULL) {
+	    string msg = section.FindS("Message");
+	    if (msg.empty() == true)
+	       msg = _("Prepare for receiving solution");
+	    Progress->SubProgress(100, msg, section.FindI("Percentage", 0));
+	 }
+	 continue;
+      } else if (section.Exists("Error") == true) {
+	 if (_error->PendingError()) {
+	    if (Progress != nullptr)
+	       Progress->Done();
+	    Progress = nullptr;
+	    _error->DumpErrors(std::cerr, GlobalError::DEBUG, false);
+	 }
+	 std::string msg = SubstVar(SubstVar(section.FindS("Message"), "\n .\n", "\n\n"), "\n ", "\n");
+	 if (msg.empty() == true) {
+	    msg = _("External planner failed without a proper error message");
+	    _error->Error("%s", msg.c_str());
+	 } else
+	    _error->Error("External planner failed with: %s", msg.substr(0,msg.find('\n')).c_str());
+	 if (Progress != nullptr)
+	    Progress->Done();
+	 std::cerr << "The planner encountered an error of type: " << section.FindS("Error") << std::endl;
+	 std::cerr << "The following information might help you to understand what is wrong:" << std::endl;
+	 std::cerr << msg << std::endl << std::endl;
+	 return false;
+      } else if (section.Exists("Unpack") == true)
+	 type = "Unpack";
+      else if (section.Exists("Configure") == true)
+	 type = "Configure";
+      else if (section.Exists("Remove") == true)
+	 type = "Remove";
+      else {
+	 char const *Start, *End;
+	 section.GetSection(Start, End);
+	 _error->Warning("Encountered an unexpected section with %d fields: %s", section.Count(), std::string(Start, End).c_str());
+	 continue;
+      }
+
+      if (type == nullptr)
+	 continue;
+      decltype(VersionCount) const id = section.FindULL(type, VersionCount);
+      if (id == VersionCount) {
+	 _error->Warning("Unable to parse %s request with id value '%s'!", type, section.FindS(type).c_str());
+	 continue;
+      } else if (id > VersionCount) {
+	 _error->Warning("ID value '%s' in %s request stanza is to high to refer to a known version!", section.FindS(type).c_str(), type);
+	 continue;
+      }
+
+      pkgCache::VerIterator Ver(PM->Cache.GetCache(), PM->Cache.GetCache().VerP + VerIdx[id]);
+      auto const Pkg = Ver.ParentPkg();
+      if (strcmp(type, "Unpack") == 0)
+	 PM->Install(Pkg, PM->FileNames[Pkg->ID]);
+      else if (strcmp(type, "Configure") == 0)
+	 PM->Configure(Pkg);
+      else if (strcmp(type, "Remove") == 0)
+	 PM->Remove(Pkg, PM->Cache[Pkg].Purge());
+   }
+   return in.Failed() == false;
+}
+									/*}}}*/
+bool EIPP::ReadRequest(int const input, std::list<std::pair<std::string,PKG_ACTION>> &actions,/*{{{*/
+      unsigned int &flags)
+{
+   actions.clear();
+   flags = 0;
+   std::string line;
+   while (ReadLine(input, line) == true)
+   {
+      // Skip empty lines before request
+      if (line.empty() == true)
+	 continue;
+      // The first Tag must be a request, so search for it
+      if (line.compare(0, 8, "Request:") != 0)
+	 continue;
+
+      while (ReadLine(input, line) == true)
+      {
+	 // empty lines are the end of the request
+	 if (line.empty() == true)
+	    return true;
+
+	 PKG_ACTION pkgact = PKG_ACTION::NOOP;
+	 if (LineStartsWithAndStrip(line, "Install:"))
+	    pkgact = PKG_ACTION::INSTALL;
+	 else if (LineStartsWithAndStrip(line, "ReInstall:"))
+	    pkgact = PKG_ACTION::REINSTALL;
+	 else if (LineStartsWithAndStrip(line, "Remove:"))
+	    pkgact = PKG_ACTION::REMOVE;
+	 else if (LineStartsWithAndStrip(line, "Architecture:"))
+	    _config->Set("APT::Architecture", line);
+	 else if (LineStartsWithAndStrip(line, "Architectures:"))
+	    _config->Set("APT::Architectures", SubstVar(line, " ", ","));
+	 else if (LineStartsWithAndStrip(line, "Planner:"))
+	    ; // purely informational line
+	 else if (LineStartsWithAndStrip(line, "Immediate-Configuration:"))
+	 {
+	    if (localStringToBool(line, true))
+	       flags |= Request::IMMEDIATE_CONFIGURATION_ALL;
+	    else
+	       flags |= Request::NO_IMMEDIATE_CONFIGURATION;
+	 }
+	 else if (ReadFlag(flags, line, "Allow-Temporary-Remove-of-Essentials:", Request::ALLOW_TEMPORARY_REMOVE_OF_ESSENTIALS))
+	    ;
+	 else
+	    _error->Warning("Unknown line in EIPP Request stanza: %s", line.c_str());
+
+	 if (pkgact == PKG_ACTION::NOOP)
+	    continue;
+	 for (auto && p: VectorizeString(line, ' '))
+	    actions.emplace_back(std::move(p), pkgact);
+      }
+   }
+   return false;
+}
+									/*}}}*/
+bool EIPP::ApplyRequest(std::list<std::pair<std::string,PKG_ACTION>> &actions,/*{{{*/
+	 pkgDepCache &Cache)
+{
+   for (auto Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg)
+   {
+      short versions = 0;
+      for (auto Ver = Pkg.VersionList(); Ver.end() == false; ++Ver)
+      {
+	 ++versions;
+	 if (Pkg.CurrentVer() == Ver)
+	    continue;
+	 Cache.SetCandidateVersion(Ver);
+      }
+      if (unlikely(versions > 2))
+	 _error->Warning("Package %s has %d versions, but should have at most 2!", Pkg.FullName().c_str(), versions);
+   }
+   for (auto && a: actions)
+   {
+      pkgCache::PkgIterator P = Cache.FindPkg(a.first);
+      if (P.end() == true)
+      {
+	 _error->Warning("Package %s is not known, so can't be acted on", a.first.c_str());
+	 continue;
+      }
+      switch (a.second)
+      {
+	 case PKG_ACTION::NOOP:
+	    _error->Warning("Package %s has NOOP as action?!?", a.first.c_str());
+	    break;
+	 case PKG_ACTION::INSTALL:
+	    Cache.MarkInstall(P, false);
+	    break;
+	 case PKG_ACTION::REINSTALL:
+	    Cache.MarkInstall(P, false);
+	    Cache.SetReInstall(P, true);
+	    break;
+	 case PKG_ACTION::REMOVE:
+	    Cache.MarkDelete(P);
+	    break;
+      }
+   }
+   return true;
+}
+									/*}}}*/