handle packages without a mandatory architecture (debian-policy §5.3)

by introducing a pseudo-architecture 'none' so that the small group of
users with these packages can get right of them without introducing too
much hassle for other users (Closes: #686346)

1 files changed, 52 insertions, 1 deletions

diff --git a/apt-pkg/pkgcachegen.cc b/apt-pkg/pkgcachegen.cc
index f70cbd02a..490c2ecbb 100644
--- a/apt-pkg/pkgcachegen.cc
+++ b/apt-pkg/pkgcachegen.cc
@@ -200,7 +200,19 @@ bool pkgCacheGenerator::MergeList(ListParser &List,
       }
 
       if (Arch.empty() == true)
-	 Arch = _config->Find("APT::Architecture");
+      {
+	 // use the pseudo arch 'none' for arch-less packages
+	 Arch = "none";
+	 /* We might built a SingleArchCache here, which we don't want to blow up
+	    just for these :none packages to a proper MultiArchCache, so just ensure
+	    that we have always a native package structure first for SingleArch */
+	 pkgCache::PkgIterator NP;
+	 if (NewPackage(NP, PackageName, _config->Find("APT::Architecture")) == false)
+	 // TRANSLATOR: The first placeholder is a package name,
+	 // the other two should be copied verbatim as they include debug info
+	 return _error->Error(_("Error occurred while processing %s (%s%d)"),
+			      PackageName.c_str(), "NewPackage", 0);
+      }
 
       // Get a pointer to the package structure
       pkgCache::PkgIterator Pkg;
@@ -418,6 +430,42 @@ bool pkgCacheGenerator::MergeListVersion(ListParser &List, pkgCache::PkgIterator
 	       return _error->Error(_("Error occurred while processing %s (%s%d)"),
 				    Pkg.Name(), "AddImplicitDepends", 1);
       }
+      /* :none packages are packages without an architecture. They are forbidden by
+	 debian-policy, so usually they will only be in (old) dpkg status files -
+	 and dpkg will complain about them - and are pretty rare. We therefore do
+	 usually not create conflicts while the parent is created, but only if a :none
+	 package (= the target) appears. This creates incorrect dependencies on :none
+	 for architecture-specific dependencies on the package we copy from, but we
+	 will ignore this bug as architecture-specific dependencies are only allowed
+	 in jessie and until then the :none packages should be extinct (hopefully).
+	 In other words: This should work long enough to allow graceful removal of
+	 these packages, it is not supposed to allow users to keep using them … */
+      if (strcmp(Pkg.Arch(), "none") == 0)
+      {
+	 pkgCache::PkgIterator M = Grp.FindPreferredPkg();
+	 if (M.end() == false && Pkg != M)
+	 {
+	    pkgCache::DepIterator D = M.RevDependsList();
+	    Dynamic<pkgCache::DepIterator> DynD(D);
+	    for (; D.end() == false; ++D)
+	    {
+	       if ((D->Type != pkgCache::Dep::Conflicts &&
+		    D->Type != pkgCache::Dep::DpkgBreaks &&
+		    D->Type != pkgCache::Dep::Replaces) ||
+		   D.ParentPkg().Group() == Grp)
+		  continue;
+
+	       map_ptrloc *OldDepLast = NULL;
+	       pkgCache::VerIterator ConVersion = D.ParentVer();
+	       // duplicate the Conflicts/Breaks/Replaces for :none arch
+	       if (D->Version == 0)
+		  NewDepends(Pkg, ConVersion, "", 0, D->Type, OldDepLast);
+	       else
+		  NewDepends(Pkg, ConVersion, D.TargetVer(),
+			     D->CompareOp, D->Type, OldDepLast);
+	    }
+	 }
+      }
    }
    if (unlikely(AddImplicitDepends(Grp, Pkg, Ver) == false))
       return _error->Error(_("Error occurred while processing %s (%s%d)"),
@@ -871,6 +919,9 @@ bool pkgCacheGenerator::ListParser::NewDepends(pkgCache::VerIterator &Ver,
 
    // Locate the target package
    pkgCache::PkgIterator Pkg = Grp.FindPkg(Arch);
+   // we don't create 'none' packages and their dependencies if we can avoid it …
+   if (Pkg.end() == true && Arch == "none")
+      return true;
    Dynamic<pkgCache::PkgIterator> DynPkg(Pkg);
    if (Pkg.end() == true) {
       if (unlikely(Owner->NewPackage(Pkg, PackageName, Arch) == false))