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)

5 files changed, 86 insertions, 8 deletions

diff --git a/apt-pkg/algorithms.cc b/apt-pkg/algorithms.cc
index 2f5fcc7ab..1b0161ffd 100644
--- a/apt-pkg/algorithms.cc
+++ b/apt-pkg/algorithms.cc
@@ -194,6 +194,11 @@ bool pkgSimulate::Remove(PkgIterator iPkg,bool Purge)
 {
    // Adapt the iterator
    PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
+   if (Pkg.end() == true)
+   {
+      std::cerr << (Purge ? "Purg" : "Remv") << " invalid package " << iPkg.FullName() << std::endl;
+      return false;
+   }
 
    Flags[Pkg->ID] = 3;
    Sim.MarkDelete(Pkg);
diff --git a/apt-pkg/deb/deblistparser.cc b/apt-pkg/deb/deblistparser.cc
index 12c6ab4c9..b84bd6fdd 100644
--- a/apt-pkg/deb/deblistparser.cc
+++ b/apt-pkg/deb/deblistparser.cc
@@ -645,6 +645,8 @@ bool debListParser::ParseDepends(pkgCache::VerIterator &Ver,
 	      a != Architectures.end(); ++a)
 	    if (NewDepends(Ver,Package,*a,Version,Op,Type) == false)
 	       return false;
+	 if (NewDepends(Ver,Package,"none",Version,Op,Type) == false)
+	    return false;
       }
       else if (MultiArchEnabled == true && found != string::npos &&
 	       strcmp(Package.c_str() + found, ":any") != 0)
@@ -658,8 +660,18 @@ bool debListParser::ParseDepends(pkgCache::VerIterator &Ver,
 	 if (NewDepends(Ver,Package,Arch,Version,Op,Type) == false)
 	    return false;
       }
-      else if (NewDepends(Ver,Package,pkgArch,Version,Op,Type) == false)
-	 return false;
+      else
+      {
+	 if (NewDepends(Ver,Package,pkgArch,Version,Op,Type) == false)
+	    return false;
+	 if ((Type == pkgCache::Dep::Conflicts ||
+	      Type == pkgCache::Dep::DpkgBreaks ||
+	      Type == pkgCache::Dep::Replaces) &&
+	     NewDepends(Ver, Package,
+			(pkgArch != "none") ? "none" : _config->Find("APT::Architecture"),
+			Version,Op,Type) == false)
+	    return false;
+      }
       if (Start == Stop)
 	 break;
    }
@@ -753,13 +765,15 @@ bool debListParser::Step()
          drop the whole section. A missing arch tag only happens (in theory)
          inside the Status file, so that is a positive return */
       string const Architecture = Section.FindS("Architecture");
-      if (Architecture.empty() == true)
-	 return true;
 
       if (Arch.empty() == true || Arch == "any" || MultiArchEnabled == false)
       {
 	 if (APT::Configuration::checkArchitecture(Architecture) == true)
 	    return true;
+	 /* parse version stanzas without an architecture only in the status file
+	    (and as misfortune bycatch flat-archives) */
+	 if ((Arch.empty() == true || Arch == "any") && Architecture.empty() == true)
+	    return true;
       }
       else
       {
diff --git a/apt-pkg/deb/dpkgpm.cc b/apt-pkg/deb/dpkgpm.cc
index ae9143e0d..c9df41d3a 100644
--- a/apt-pkg/deb/dpkgpm.cc
+++ b/apt-pkg/deb/dpkgpm.cc
@@ -1131,7 +1131,9 @@ bool pkgDPkgPM::Go(int OutStatusFd)
 	    if (I->Op == Item::Configure && disappearedPkgs.find(I->Pkg.Name()) != disappearedPkgs.end())
 	       continue;
 	    // We keep this here to allow "smooth" transitions from e.g. multiarch dpkg/ubuntu to dpkg/debian
-	    if (dpkgMultiArch == false && (I->Pkg.Arch() == nativeArch || !strcmp(I->Pkg.Arch(), "all")))
+	    if (dpkgMultiArch == false && (I->Pkg.Arch() == nativeArch ||
+					   strcmp(I->Pkg.Arch(), "all") == 0 ||
+					   strcmp(I->Pkg.Arch(), "none") == 0))
 	    {
 	       char const * const name = I->Pkg.Name();
 	       ADDARG(name);
@@ -1148,7 +1150,9 @@ bool pkgDPkgPM::Go(int OutStatusFd)
                }
 	       else
 		  PkgVer = Cache[I->Pkg].InstVerIter(Cache);
-               if (PkgVer.end() == false)
+	       if (strcmp(I->Pkg.Arch(), "none") == 0)
+		  ; // never arch-qualify a package without an arch
+	       else if (PkgVer.end() == false)
                   name.append(":").append(PkgVer.Arch());
                else
                   _error->Warning("Can not find PkgVer for '%s'", name.c_str());
diff --git a/apt-pkg/pkgcache.cc b/apt-pkg/pkgcache.cc
index 9acb7da72..353172d8a 100644
--- a/apt-pkg/pkgcache.cc
+++ b/apt-pkg/pkgcache.cc
@@ -238,7 +238,7 @@ pkgCache::PkgIterator pkgCache::FindPkg(const string &Name) {
 // ---------------------------------------------------------------------
 /* Returns 0 on error, pointer to the package otherwise */
 pkgCache::PkgIterator pkgCache::FindPkg(const string &Name, string const &Arch) {
-	if (MultiArchCache() == false) {
+	if (MultiArchCache() == false && Arch != "none") {
 		if (Arch == "native" || Arch == "all" || Arch == "any" ||
 		    Arch == NativeArch())
 			return SingleArchFindPkg(Name);
@@ -376,6 +376,10 @@ pkgCache::PkgIterator pkgCache::GrpIterator::FindPreferredPkg(bool const &Prefer
 		if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
 			return Pkg;
 	}
+	// packages without an architecture
+	Pkg = FindPkg("none");
+	if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
+		return Pkg;
 
 	if (PreferNonVirtual == true)
 		return FindPreferredPkg(false);
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))