remove the Section member from package struct

A version belongs to a section and has hence a section member of its
own. A package on the other hand can have multiple versions from
different sections. This was "solved" by using the section which was
parsed first as order of sources.list defines, but that is obviously a
horribly unpredictable thing.

We therefore directly remove this struct member to free some space and
mark the access method as deprecated, which is told to return the
section of the 'newest' known version, which is at least predictable,
but possible not what it returned before – but nobody knows.

Users are way better of with the Section() as returned by the version
they are dealing with. It is likely the same for all versions of a
package, but in the few cases it isn't, it is important (like packages
moving from main/* to contrib/* or into oldlibs …).

apt-pkg/cacheiterators.h

@@ -160,7 +160,11 @@ class pkgCache::PkgIterator: public Iterator<Package, PkgIterator> {
 
 	// Accessors
 	inline const char *Name() const {return S->Name == 0?0:Owner->StrP + S->Name;}
-	inline const char *Section() const {return S->Section == 0?0:Owner->StrP + S->Section;}
+	// Versions have sections - and packages can have different versions with different sections
+	// so this interface is broken by design. It used to return the section of the "first parsed
+	// package stanza", but as this can potentially be anything it now returns the section of the
+	// newest version instead (if any). aka: Run as fast as you can to Version.Section().
+	APT_DEPRECATED const char *Section() const;
 	inline bool Purge() const {return S->CurrentState == pkgCache::State::Purge ||
 		(S->CurrentVer == 0 && S->CurrentState == pkgCache::State::NotInstalled);}
 	inline const char *Arch() const {return S->Arch == 0?0:Owner->StrP + S->Arch;}

apt-pkg/cacheset.h

@@ -118,7 +118,16 @@ public:
 		inline const char *Name() const {return getPkg().Name(); }
 		inline std::string FullName(bool const Pretty) const { return getPkg().FullName(Pretty); }
 		inline std::string FullName() const { return getPkg().FullName(); }
-		inline const char *Section() const {return getPkg().Section(); }
+		APT_DEPRECATED inline const char *Section() const {
+#if __GNUC__ >= 4
+	#pragma GCC diagnostic push
+	#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+	   return getPkg().Section();
+#if __GNUC__ >= 4
+	#pragma GCC diagnostic pop
+#endif
+		}
 		inline bool Purge() const {return getPkg().Purge(); }
 		inline const char *Arch() const {return getPkg().Arch(); }
 		inline pkgCache::GrpIterator Group() const { return getPkg().Group(); }

apt-pkg/deb/deblistparser.cc

@@ -255,9 +255,6 @@ MD5SumValue debListParser::Description_md5()
 bool debListParser::UsePackage(pkgCache::PkgIterator &Pkg,
 			       pkgCache::VerIterator &Ver)
 {
-   if (Pkg->Section == 0)
-      Pkg->Section = UniqFindTagWrite("Section");
-
    string const static myArch = _config->Find("APT::Architecture");
    // Possible values are: "all", "native", "installed" and "none"
    // The "installed" mode is handled by ParseStatus(), See #544481 and friends.

apt-pkg/depcache.cc

@@ -1225,7 +1225,7 @@ bool pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
 	       continue;
 	    }
 	    // now check if we should consider it a automatic dependency or not
-	    if(InstPkg->CurrentVer == 0 && Pkg->Section != 0 && ConfigValueInSubTree("APT::Never-MarkAuto-Sections", Pkg.Section()))
+	    if(InstPkg->CurrentVer == 0 && InstVer->Section != 0 && ConfigValueInSubTree("APT::Never-MarkAuto-Sections", InstVer.Section()))
 	    {
 	       if(DebugAutoInstall == true)
 		  std::clog << OutputInDepth(Depth) << "Setting NOT as auto-installed (direct "

apt-pkg/pkgcache.cc

@@ -527,7 +527,10 @@ operator<<(std::ostream& out, pkgCache::PkgIterator Pkg)
       out << " -> " << candidate;
    if ( newest != "none" && candidate != newest)
       out << " | " << newest;
-   out << " > ( " << string(Pkg.Section()==0?"none":Pkg.Section()) << " )";
+   if (Pkg->VersionList == 0)
+      out << " > ( none )";
+   else
+      out << " > ( " << string(Pkg.VersionList().Section()==0?"unknown":Pkg.VersionList().Section()) << " )";
    return out;
 }
 									/*}}}*/
@@ -1039,3 +1042,9 @@ bool pkgCache::PrvIterator::IsMultiArchImplicit() const
    return false;
 }
 									/*}}}*/
+APT_DEPRECATED APT_PURE const char * pkgCache::PkgIterator::Section() const {/*{{{*/
+   if (S->VersionList == 0)
+      return 0;
+   return VersionList().Section();
+}
+									/*}}}*/

apt-pkg/pkgcache.h

@@ -392,11 +392,6 @@ struct pkgCache::Package
    map_pointer_t VersionList;       // Version
    /** \brief index to the installed version */
    map_pointer_t CurrentVer;        // Version
-   /** \brief indicates the deduced section
-
-       Should be the index to the string "Unknown" or to the section
-       of the last parsed item. */
-   map_stringitem_t Section;
    /** \brief index of the group this package belongs to */
    map_pointer_t Group;             // Group the Package belongs to