* cherry pick revision 2173 from lp:~donkult/apt/sid

- M-A:same lockstep unpack should operate on installed
  packages first (LP: #835625)

1 files changed, 26 insertions, 5 deletions

diff --git a/apt-pkg/packagemanager.cc b/apt-pkg/packagemanager.cc
index db18c5521..c6815658b 100644
--- a/apt-pkg/packagemanager.cc
+++ b/apt-pkg/packagemanager.cc
@@ -603,18 +603,39 @@ bool pkgPackageManager::SmartUnPack(PkgIterator Pkg, bool const Immediate)
 
    List->Flag(Pkg,pkgOrderList::UnPacked,pkgOrderList::States);
 
-   if ((instVer->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
+   if (Immediate == true && instVer->MultiArch == pkgCache::Version::Same)
+   {
+      /* Do lockstep M-A:same unpacking in two phases:
+	 First unpack all installed architectures, then the not installed.
+	 This way we avoid that M-A: enabled packages are installed before
+	 their older non-M-A enabled packages are replaced by newer versions */
+      bool const installed = Pkg->CurrentVer != 0;
+      if (installed == true && Install(Pkg,FileNames[Pkg->ID]) == false)
+	 return false;
       for (PkgIterator P = Pkg.Group().PackageList();
 	   P.end() == false; P = Pkg.Group().NextPkg(P))
       {
-	 if (Pkg == P || List->IsFlag(P,pkgOrderList::UnPacked) == true ||
+	 if (P->CurrentVer == 0 || P == Pkg || List->IsFlag(P,pkgOrderList::UnPacked) == true ||
 	     Cache[P].InstallVer == 0 || (P.CurrentVer() == Cache[P].InstallVer &&
 	      (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall))
 	    continue;
-	 SmartUnPack(P, false);
+	 if (SmartUnPack(P, false) == false)
+	    return false;
       }
-
-   if(Install(Pkg,FileNames[Pkg->ID]) == false)
+      if (installed == false && Install(Pkg,FileNames[Pkg->ID]) == false)
+	 return false;
+      for (PkgIterator P = Pkg.Group().PackageList();
+	   P.end() == false; P = Pkg.Group().NextPkg(P))
+      {
+	 if (P->CurrentVer != 0 || P == Pkg || List->IsFlag(P,pkgOrderList::UnPacked) == true ||
+	     Cache[P].InstallVer == 0 || (P.CurrentVer() == Cache[P].InstallVer &&
+	      (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall))
+	    continue;
+	 if (SmartUnPack(P, false) == false)
+	    return false;
+      }
+   }
+   else if (Install(Pkg,FileNames[Pkg->ID]) == false)
       return false;
 
    // Perform immedate configuration of the package.