* cmdline/cacheset.cc:

  - doesn't include it in the library for now as it is too volatile

3 files changed, 606 insertions, 2 deletions

diff --git a/cmdline/cacheset.cc b/cmdline/cacheset.cc
new file mode 100644
index 000000000..fde52168a
--- /dev/null
+++ b/cmdline/cacheset.cc
@@ -0,0 +1,330 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Simple wrapper around a std::set to provide a similar interface to
+   a set of cache structures as to the complete set of all structures
+   in the pkgCache. Currently only Package is supported.
+
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <apt-pkg/aptconfiguration.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/cacheset.h>
+#include <apt-pkg/strutl.h>
+#include <apt-pkg/versionmatch.h>
+
+#include <apti18n.h>
+
+#include <vector>
+
+#include <regex.h>
+									/*}}}*/
+namespace APT {
+// FromRegEx - Return all packages in the cache matching a pattern	/*{{{*/
+PackageSet PackageSet::FromRegEx(pkgCacheFile &Cache, std::string pattern, std::ostream &out) {
+	PackageSet pkgset;
+	std::string arch = "native";
+	static const char * const isregex = ".?+*|[^$";
+
+	if (pattern.find_first_of(isregex) == std::string::npos)
+		return pkgset;
+
+	size_t archfound = pattern.find_last_of(':');
+	if (archfound != std::string::npos) {
+		arch = pattern.substr(archfound+1);
+		if (arch.find_first_of(isregex) == std::string::npos)
+			pattern.erase(archfound);
+		else
+			arch = "native";
+	}
+
+	regex_t Pattern;
+	int Res;
+	if ((Res = regcomp(&Pattern, pattern.c_str() , REG_EXTENDED | REG_ICASE | REG_NOSUB)) != 0) {
+		char Error[300];
+		regerror(Res, &Pattern, Error, sizeof(Error));
+		_error->Error(_("Regex compilation error - %s"), Error);
+		return pkgset;
+	}
+
+	for (pkgCache::GrpIterator Grp = Cache.GetPkgCache()->GrpBegin(); Grp.end() == false; ++Grp)
+	{
+		if (regexec(&Pattern, Grp.Name(), 0, 0, 0) != 0)
+			continue;
+		pkgCache::PkgIterator Pkg = Grp.FindPkg(arch);
+		if (Pkg.end() == true) {
+			if (archfound == std::string::npos) {
+				std::vector<std::string> archs = APT::Configuration::getArchitectures();
+				for (std::vector<std::string>::const_iterator a = archs.begin();
+				     a != archs.end() && Pkg.end() != true; ++a)
+					Pkg = Grp.FindPkg(*a);
+			}
+			if (Pkg.end() == true)
+				continue;
+		}
+
+		ioprintf(out, _("Note, selecting %s for regex '%s'\n"),
+			 Pkg.FullName(true).c_str(), pattern.c_str());
+
+		pkgset.insert(Pkg);
+	}
+
+	regfree(&Pattern);
+
+	return pkgset;
+}
+									/*}}}*/
+// GroupedFromCommandLine - Return all versions specified on commandline/*{{{*/
+std::map<unsigned short, PackageSet> PackageSet::GroupedFromCommandLine(
+		pkgCacheFile &Cache, const char **cmdline,
+		std::list<PackageSet::Modifier> const &mods,
+		unsigned short const &fallback, std::ostream &out) {
+	std::map<unsigned short, PackageSet> pkgsets;
+	for (const char **I = cmdline; *I != 0; ++I) {
+		unsigned short modID = fallback;
+		std::string str = *I;
+		for (std::list<PackageSet::Modifier>::const_iterator mod = mods.begin();
+		     mod != mods.end(); ++mod) {
+			size_t const alength = strlen(mod->Alias);
+			switch(mod->Pos) {
+			case PackageSet::Modifier::POSTFIX:
+				if (str.compare(str.length() - alength, alength,
+						mod->Alias, 0, alength) != 0)
+					continue;
+				str.erase(str.length() - alength);
+				modID = mod->ID;
+				break;
+			case PackageSet::Modifier::PREFIX:
+				continue;
+			case PackageSet::Modifier::NONE:
+				continue;
+			}
+			break;
+		}
+		PackageSet pset = PackageSet::FromString(Cache, str, out);
+		pkgsets[modID].insert(pset.begin(), pset.end());
+	}
+	return pkgsets;
+}
+									/*}}}*/
+// FromCommandLine - Return all packages specified on commandline	/*{{{*/
+PackageSet PackageSet::FromCommandLine(pkgCacheFile &Cache, const char **cmdline, std::ostream &out) {
+	PackageSet pkgset;
+	for (const char **I = cmdline; *I != 0; ++I) {
+		PackageSet pset = FromString(Cache, *I, out);
+		pkgset.insert(pset.begin(), pset.end());
+	}
+	return pkgset;
+}
+									/*}}}*/
+// FromString - Return all packages matching a specific string		/*{{{*/
+PackageSet PackageSet::FromString(pkgCacheFile &Cache, std::string const &str, std::ostream &out) {
+	std::string pkg = str;
+	size_t archfound = pkg.find_last_of(':');
+	std::string arch;
+	if (archfound != std::string::npos) {
+		arch = pkg.substr(archfound+1);
+		pkg.erase(archfound);
+	}
+
+	pkgCache::PkgIterator Pkg;
+	if (arch.empty() == true) {
+		pkgCache::GrpIterator Grp = Cache.GetPkgCache()->FindGrp(pkg);
+		if (Grp.end() == false)
+			Pkg = Grp.FindPreferredPkg();
+	} else
+		Pkg = Cache.GetPkgCache()->FindPkg(pkg, arch);
+
+	if (Pkg.end() == false) {
+		PackageSet pkgset;
+		pkgset.insert(Pkg);
+		return pkgset;
+	}
+	PackageSet regex = FromRegEx(Cache, str, out);
+	if (regex.empty() == true)
+		_error->Warning(_("Unable to locate package %s"), str.c_str());
+	return regex;
+}
+									/*}}}*/
+// GroupedFromCommandLine - Return all versions specified on commandline/*{{{*/
+std::map<unsigned short, VersionSet> VersionSet::GroupedFromCommandLine(
+		pkgCacheFile &Cache, const char **cmdline,
+		std::list<VersionSet::Modifier> const &mods,
+		unsigned short const &fallback, std::ostream &out) {
+	std::map<unsigned short, VersionSet> versets;
+	for (const char **I = cmdline; *I != 0; ++I) {
+		unsigned short modID = fallback;
+		VersionSet::Version select = VersionSet::NEWEST;
+		std::string str = *I;
+		for (std::list<VersionSet::Modifier>::const_iterator mod = mods.begin();
+		     mod != mods.end(); ++mod) {
+			if (modID == fallback && mod->ID == fallback)
+				select = mod->SelectVersion;
+			size_t const alength = strlen(mod->Alias);
+			switch(mod->Pos) {
+			case VersionSet::Modifier::POSTFIX:
+				if (str.compare(str.length() - alength, alength,
+						mod->Alias, 0, alength) != 0)
+					continue;
+				str.erase(str.length() - alength);
+				modID = mod->ID;
+				select = mod->SelectVersion;
+				break;
+			case VersionSet::Modifier::PREFIX:
+				continue;
+			case VersionSet::Modifier::NONE:
+				continue;
+			}
+			break;
+		}
+		VersionSet vset = VersionSet::FromString(Cache, str, select , out);
+		versets[modID].insert(vset.begin(), vset.end());
+	}
+	return versets;
+}
+									/*}}}*/
+// FromCommandLine - Return all versions specified on commandline	/*{{{*/
+APT::VersionSet VersionSet::FromCommandLine(pkgCacheFile &Cache, const char **cmdline,
+		APT::VersionSet::Version const &fallback, std::ostream &out) {
+	VersionSet verset;
+	for (const char **I = cmdline; *I != 0; ++I) {
+		VersionSet vset = VersionSet::FromString(Cache, *I, fallback, out);
+		verset.insert(vset.begin(), vset.end());
+	}
+	return verset;
+}
+									/*}}}*/
+// FromString - Returns all versions spedcified by a string		/*{{{*/
+APT::VersionSet VersionSet::FromString(pkgCacheFile &Cache, std::string pkg,
+		APT::VersionSet::Version const &fallback, std::ostream &out) {
+	std::string ver;
+	bool verIsRel = false;
+	size_t const vertag = pkg.find_last_of("/=");
+	if (vertag != string::npos) {
+		ver = pkg.substr(vertag+1);
+		verIsRel = (pkg[vertag] == '/');
+		pkg.erase(vertag);
+	}
+	PackageSet pkgset = PackageSet::FromString(Cache, pkg.c_str(), out);
+	VersionSet verset;
+	for (PackageSet::const_iterator P = pkgset.begin();
+	     P != pkgset.end(); ++P) {
+		if (vertag == string::npos) {
+			AddSelectedVersion(Cache, verset, P, fallback);
+			continue;
+		}
+		pkgCache::VerIterator V;
+		if (ver == "installed")
+			V = getInstalledVer(Cache, P);
+		else if (ver == "candidate")
+			V = getCandidateVer(Cache, P);
+		else {
+			pkgVersionMatch Match(ver, (verIsRel == true ? pkgVersionMatch::Release :
+					pkgVersionMatch::Version));
+			V = Match.Find(P);
+			if (V.end() == true) {
+				if (verIsRel == true)
+					_error->Error(_("Release '%s' for '%s' was not found"),
+							ver.c_str(), P.FullName(true).c_str());
+				else
+					_error->Error(_("Version '%s' for '%s' was not found"),
+							ver.c_str(), P.FullName(true).c_str());
+				continue;
+			}
+		}
+		if (V.end() == true)
+			continue;
+		if (ver == V.VerStr())
+			ioprintf(out, _("Selected version '%s' (%s) for '%s'\n"),
+				 V.VerStr(), V.RelStr().c_str(), P.FullName(true).c_str());
+		verset.insert(V);
+	}
+	return verset;
+}
+									/*}}}*/
+// AddSelectedVersion - add version from package based on fallback	/*{{{*/
+bool VersionSet::AddSelectedVersion(pkgCacheFile &Cache, VersionSet &verset,
+		pkgCache::PkgIterator const &P, VersionSet::Version const &fallback,
+		bool const &AllowError) {
+	pkgCache::VerIterator V;
+	switch(fallback) {
+	case VersionSet::ALL:
+		if (P->VersionList != 0)
+			for (V = P.VersionList(); V.end() != true; ++V)
+				verset.insert(V);
+		else if (AllowError == false)
+			return _error->Error(_("Can't select versions from package '%s' as it purely virtual"), P.FullName(true).c_str());
+		else
+			return false;
+		break;
+	case VersionSet::CANDANDINST:
+		verset.insert(getInstalledVer(Cache, P, AllowError));
+		verset.insert(getCandidateVer(Cache, P, AllowError));
+		break;
+	case VersionSet::CANDIDATE:
+		verset.insert(getCandidateVer(Cache, P, AllowError));
+		break;
+	case VersionSet::INSTALLED:
+		verset.insert(getInstalledVer(Cache, P, AllowError));
+		break;
+	case VersionSet::CANDINST:
+		V = getCandidateVer(Cache, P, true);
+		if (V.end() == true)
+			V = getInstalledVer(Cache, P, true);
+		if (V.end() == false)
+			verset.insert(V);
+		else if (AllowError == false)
+			return _error->Error(_("Can't select installed nor candidate version from package '%s' as it has neither of them"), P.FullName(true).c_str());
+		else
+			return false;
+		break;
+	case VersionSet::INSTCAND:
+		V = getInstalledVer(Cache, P, true);
+		if (V.end() == true)
+			V = getCandidateVer(Cache, P, true);
+		if (V.end() == false)
+			verset.insert(V);
+		else if (AllowError == false)
+			return _error->Error(_("Can't select installed nor candidate version from package '%s' as it has neither of them"), P.FullName(true).c_str());
+		else
+			return false;
+		break;
+	case VersionSet::NEWEST:
+		if (P->VersionList != 0)
+			verset.insert(P.VersionList());
+		else if (AllowError == false)
+			return _error->Error(_("Can't select newest version from package '%s' as it is purely virtual"), P.FullName(true).c_str());
+		else
+			return false;
+		break;
+	}
+	return true;
+}
+									/*}}}*/
+// getCandidateVer - Returns the candidate version of the given package	/*{{{*/
+pkgCache::VerIterator VersionSet::getCandidateVer(pkgCacheFile &Cache,
+		pkgCache::PkgIterator const &Pkg, bool const &AllowError) {
+	pkgCache::VerIterator Cand;
+	if (Cache.IsDepCacheBuilt() == true)
+		Cand = Cache[Pkg].CandidateVerIter(Cache);
+	else {
+		if (unlikely(Cache.BuildPolicy() == false))
+			return pkgCache::VerIterator(*Cache);
+		Cand = Cache.GetPolicy()->GetCandidateVer(Pkg);
+	}
+	if (AllowError == false && Cand.end() == true)
+		_error->Error(_("Can't select candidate version from package %s as it has no candidate"), Pkg.FullName(true).c_str());
+	return Cand;
+}
+									/*}}}*/
+// getInstalledVer - Returns the installed version of the given package	/*{{{*/
+pkgCache::VerIterator VersionSet::getInstalledVer(pkgCacheFile &Cache,
+		pkgCache::PkgIterator const &Pkg, bool const &AllowError) {
+	if (AllowError == false && Pkg->CurrentVer == 0)
+		_error->Error(_("Can't select installed version from package %s as it is not installed"), Pkg.FullName(true).c_str());
+	return Pkg.CurrentVer();
+}
+									/*}}}*/
+}
diff --git a/cmdline/cacheset.h b/cmdline/cacheset.h
new file mode 100644
index 000000000..2bc268380
--- /dev/null
+++ b/cmdline/cacheset.h
@@ -0,0 +1,274 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/** \file cacheset.h
+   Wrappers around std::set to have set::iterators which behave
+   similar to the Iterators of the cache structures.
+
+   Provides also a few helper methods which work with these sets */
+									/*}}}*/
+#ifndef APT_CACHESET_H
+#define APT_CACHESET_H
+// Include Files							/*{{{*/
+#include <iostream>
+#include <fstream>
+#include <list>
+#include <map>
+#include <set>
+#include <string>
+
+#include <apt-pkg/cachefile.h>
+#include <apt-pkg/pkgcache.h>
+									/*}}}*/
+namespace APT {
+class PackageSet : public std::set<pkgCache::PkgIterator> {		/*{{{*/
+/** \class APT::PackageSet
+
+    Simple wrapper around a std::set to provide a similar interface to
+    a set of packages as to the complete set of all packages in the
+    pkgCache. */
+public:									/*{{{*/
+	/** \brief smell like a pkgCache::PkgIterator */
+	class const_iterator : public std::set<pkgCache::PkgIterator>::const_iterator {
+	public:
+		const_iterator(std::set<pkgCache::PkgIterator>::const_iterator x) :
+			 std::set<pkgCache::PkgIterator>::const_iterator(x) {}
+
+		operator pkgCache::PkgIterator(void) { return **this; }
+
+		inline const char *Name() const {return (**this).Name(); }
+		inline std::string FullName(bool const &Pretty) const { return (**this).FullName(Pretty); }
+		inline std::string FullName() const { return (**this).FullName(); }
+		inline const char *Section() const {return (**this).Section(); }
+		inline bool Purge() const {return (**this).Purge(); }
+		inline const char *Arch() const {return (**this).Arch(); }
+		inline pkgCache::GrpIterator Group() const { return (**this).Group(); }
+		inline pkgCache::VerIterator VersionList() const { return (**this).VersionList(); }
+		inline pkgCache::VerIterator CurrentVer() const { return (**this).CurrentVer(); }
+		inline pkgCache::DepIterator RevDependsList() const { return (**this).RevDependsList(); }
+		inline pkgCache::PrvIterator ProvidesList() const { return (**this).ProvidesList(); }
+		inline pkgCache::PkgIterator::OkState State() const { return (**this).State(); }
+		inline const char *CandVersion() const { return (**this).CandVersion(); }
+		inline const char *CurVersion() const { return (**this).CurVersion(); }
+		inline pkgCache *Cache() const { return (**this).Cache(); };
+		inline unsigned long Index() const {return (**this).Index();};
+		// we have only valid iterators here
+		inline bool end() const { return false; };
+
+		friend std::ostream& operator<<(std::ostream& out, const_iterator i) { return operator<<(out, (*i)); }
+
+		inline pkgCache::Package const * operator->() const {
+			return &***this;
+		};
+	};
+	// 103. set::iterator is required to be modifiable, but this allows modification of keys
+	typedef APT::PackageSet::const_iterator iterator;
+
+	using std::set<pkgCache::PkgIterator>::insert;
+	inline void insert(pkgCache::PkgIterator const &P) { if (P.end() == false) std::set<pkgCache::PkgIterator>::insert(P); };
+
+	/** \brief returns all packages in the cache whose name matchs a given pattern
+
+	    A simple helper responsible for executing a regular expression on all
+	    package names in the cache. Optional it prints a a notice about the
+	    packages chosen cause of the given package.
+	    \param Cache the packages are in
+	    \param pattern regular expression for package names
+	    \param out stream to print the notice to */
+	static APT::PackageSet FromRegEx(pkgCacheFile &Cache, std::string pattern, std::ostream &out);
+	static APT::PackageSet FromRegEx(pkgCacheFile &Cache, std::string const &pattern) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::PackageSet::FromRegEx(Cache, pattern, out);
+	}
+
+	/** \brief returns all packages specified by a string
+
+	    \param Cache the packages are in
+	    \param string String the package name(s) should be extracted from
+	    \param out stream to print various notices to */
+	static APT::PackageSet FromString(pkgCacheFile &Cache, std::string const &string, std::ostream &out);
+	static APT::PackageSet FromString(pkgCacheFile &Cache, std::string const &string) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::PackageSet::FromString(Cache, string, out);
+	}
+
+	/** \brief returns all packages specified on the commandline
+
+	    Get all package names from the commandline and executes regex's if needed.
+	    No special package command is supported, just plain names.
+	    \param Cache the packages are in
+	    \param cmdline Command line the package names should be extracted from
+	    \param out stream to print various notices to */
+	static APT::PackageSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline, std::ostream &out);
+	static APT::PackageSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::PackageSet::FromCommandLine(Cache, cmdline, out);
+	}
+
+	struct Modifier {
+		enum Position { NONE, PREFIX, POSTFIX };
+		unsigned short ID;
+		const char * const Alias;
+		Position Pos;
+		Modifier (unsigned short const &id, const char * const alias, Position const &pos) : ID(id), Alias(alias), Pos(pos) {};
+	};
+
+	static std::map<unsigned short, PackageSet> GroupedFromCommandLine(
+		pkgCacheFile &Cache, const char **cmdline,
+		std::list<PackageSet::Modifier> const &mods,
+		unsigned short const &fallback, std::ostream &out);
+	static std::map<unsigned short, PackageSet> GroupedFromCommandLine(
+		pkgCacheFile &Cache, const char **cmdline,
+		std::list<PackageSet::Modifier> const &mods,
+		unsigned short const &fallback) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::PackageSet::GroupedFromCommandLine(Cache, cmdline,
+				mods, fallback, out);
+	}
+									/*}}}*/
+};									/*}}}*/
+class VersionSet : public std::set<pkgCache::VerIterator> {		/*{{{*/
+/** \class APT::VersionSet
+
+    Simple wrapper around a std::set to provide a similar interface to
+    a set of versions as to the complete set of all versions in the
+    pkgCache. */
+public:									/*{{{*/
+	/** \brief smell like a pkgCache::VerIterator */
+	class const_iterator : public std::set<pkgCache::VerIterator>::const_iterator {
+	public:
+		const_iterator(std::set<pkgCache::VerIterator>::const_iterator x) :
+			 std::set<pkgCache::VerIterator>::const_iterator(x) {}
+
+		operator pkgCache::VerIterator(void) { return **this; }
+
+		inline pkgCache *Cache() const { return (**this).Cache(); };
+		inline unsigned long Index() const {return (**this).Index();};
+		// we have only valid iterators here
+		inline bool end() const { return false; };
+
+		inline pkgCache::Version const * operator->() const {
+			return &***this;
+		};
+
+		inline int CompareVer(const pkgCache::VerIterator &B) const { return (**this).CompareVer(B); };
+		inline const char *VerStr() const { return (**this).VerStr(); };
+		inline const char *Section() const { return (**this).Section(); };
+		inline const char *Arch() const { return (**this).Arch(); };
+		inline const char *Arch(bool const pseudo) const { return (**this).Arch(pseudo); };
+		inline pkgCache::PkgIterator ParentPkg() const { return (**this).ParentPkg(); };
+		inline pkgCache::DescIterator DescriptionList() const { return (**this).DescriptionList(); };
+		inline pkgCache::DescIterator TranslatedDescription() const { return (**this).TranslatedDescription(); };
+		inline pkgCache::DepIterator DependsList() const { return (**this).DependsList(); };
+		inline pkgCache::PrvIterator ProvidesList() const { return (**this).ProvidesList(); };
+		inline pkgCache::VerFileIterator FileList() const { return (**this).FileList(); };
+		inline bool Downloadable() const { return (**this).Downloadable(); };
+		inline const char *PriorityType() const { return (**this).PriorityType(); };
+		inline string RelStr() const { return (**this).RelStr(); };
+		inline bool Automatic() const { return (**this).Automatic(); };
+		inline bool Pseudo() const { return (**this).Pseudo(); };
+		inline pkgCache::VerFileIterator NewestFile() const { return (**this).NewestFile(); };
+	};
+	// 103. set::iterator is required to be modifiable, but this allows modification of keys
+	typedef APT::VersionSet::const_iterator iterator;
+
+	using std::set<pkgCache::VerIterator>::insert;
+	inline void insert(pkgCache::VerIterator const &V) { if (V.end() == false) std::set<pkgCache::VerIterator>::insert(V); };
+
+	/** \brief specifies which version(s) will be returned if non is given */
+	enum Version {
+		/** All versions */
+		ALL,
+		/** Candidate and installed version */
+		CANDANDINST,
+		/** Candidate version */
+		CANDIDATE,
+		/** Installed version */
+		INSTALLED,
+		/** Candidate or if non installed version */
+		CANDINST,
+		/** Installed or if non candidate version */
+		INSTCAND,
+		/** Newest version */
+		NEWEST
+	};
+
+	/** \brief returns all versions specified on the commandline
+
+	    Get all versions from the commandline, uses given default version if
+	    non specifically requested  and executes regex's if needed on names.
+	    \param Cache the packages and versions are in
+	    \param cmdline Command line the versions should be extracted from
+	    \param out stream to print various notices to */
+	static APT::VersionSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline,
+			APT::VersionSet::Version const &fallback, std::ostream &out);
+	static APT::VersionSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline,
+			APT::VersionSet::Version const &fallback) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::VersionSet::FromCommandLine(Cache, cmdline, fallback, out);
+	}
+	static APT::VersionSet FromCommandLine(pkgCacheFile &Cache, const char **cmdline) {
+		return APT::VersionSet::FromCommandLine(Cache, cmdline, CANDINST);
+	}
+
+	static APT::VersionSet FromString(pkgCacheFile &Cache, std::string pkg,
+			APT::VersionSet::Version const &fallback, std::ostream &out);
+	static APT::VersionSet FromString(pkgCacheFile &Cache, std::string pkg,
+			APT::VersionSet::Version const &fallback) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::VersionSet::FromString(Cache, pkg, fallback, out);
+	}
+	static APT::VersionSet FromString(pkgCacheFile &Cache, std::string pkg) {
+		return APT::VersionSet::FromString(Cache, pkg, CANDINST);
+	}
+
+	struct Modifier {
+		enum Position { NONE, PREFIX, POSTFIX };
+		unsigned short ID;
+		const char * const Alias;
+		Position Pos;
+		VersionSet::Version SelectVersion;
+		Modifier (unsigned short const &id, const char * const alias, Position const &pos,
+			  VersionSet::Version const &select) : ID(id), Alias(alias), Pos(pos),
+			 SelectVersion(select) {};
+	};
+
+	static std::map<unsigned short, VersionSet> GroupedFromCommandLine(
+		pkgCacheFile &Cache, const char **cmdline,
+		std::list<VersionSet::Modifier> const &mods,
+		unsigned short const &fallback, std::ostream &out);
+	static std::map<unsigned short, VersionSet> GroupedFromCommandLine(
+		pkgCacheFile &Cache, const char **cmdline,
+		std::list<VersionSet::Modifier> const &mods,
+		unsigned short const &fallback) {
+		std::ostream out (std::ofstream("/dev/null").rdbuf());
+		return APT::VersionSet::GroupedFromCommandLine(Cache, cmdline,
+				mods, fallback, out);
+	}
+									/*}}}*/
+protected:								/*{{{*/
+
+	/** \brief returns the candidate version of the package
+
+	    \param Cache to be used to query for information
+	    \param Pkg we want the candidate version from this package
+	    \param AllowError add an error to the stack if not */
+	static pkgCache::VerIterator getCandidateVer(pkgCacheFile &Cache,
+		pkgCache::PkgIterator const &Pkg, bool const &AllowError = false);
+
+	/** \brief returns the installed version of the package
+
+	    \param Cache to be used to query for information
+	    \param Pkg we want the installed version from this package
+	    \param AllowError add an error to the stack if not */
+	static pkgCache::VerIterator getInstalledVer(pkgCacheFile &Cache,
+		pkgCache::PkgIterator const &Pkg, bool const &AllowError = false);
+
+
+	static bool AddSelectedVersion(pkgCacheFile &Cache, VersionSet &verset,
+		pkgCache::PkgIterator const &P, VersionSet::Version const &fallback,
+		bool const &AllowError = false);
+
+									/*}}}*/
+};									/*}}}*/
+}
+#endif
diff --git a/cmdline/makefile b/cmdline/makefile
index 917ccc96a..4ffe49ee0 100644
--- a/cmdline/makefile
+++ b/cmdline/makefile
@@ -9,14 +9,14 @@ include ../buildlib/defaults.mak
 PROGRAM=apt-cache
 SLIBS = -lapt-pkg $(INTLLIBS)
 LIB_MAKES = apt-pkg/makefile
-SOURCE = apt-cache.cc
+SOURCE = apt-cache.cc cacheset.cc
 include $(PROGRAM_H)
 
 # The apt-get program
 PROGRAM=apt-get
 SLIBS = -lapt-pkg -lutil $(INTLLIBS)
 LIB_MAKES = apt-pkg/makefile
-SOURCE = apt-get.cc acqprogress.cc
+SOURCE = apt-get.cc acqprogress.cc cacheset.cc
 include $(PROGRAM_H)
 
 # The apt-config program