Merged from trunk 6580:6590

   Merged from trunk 6580:6590

   +------------------------------------------------------------------------+
   | 6580    | Fix namespace for S_ISUID and S_ISGID.                       |
   | zmedico |                                                              |
   |---------+--------------------------------------------------------------|
   | 6581    | More namespace fixes.                                        |
   | zmedico |                                                              |
   |---------+--------------------------------------------------------------|
   | 6582    | Punt the portdbapi.getsize() function since it's unused and  |
   | zmedico | broken (mysum referenced before assignment).                 |
   |---------+--------------------------------------------------------------|
   | 6583    | Fix missing red import.                                      |
   | zmedico |                                                              |
   |---------+--------------------------------------------------------------|
   | 6584    | Split reading/writing of $PKGDIR/Packages into a             |
   | zmedico | PackageIndex class.                                          |
   |---------+--------------------------------------------------------------|
   | 6585    | Discard metadata from the Packages file if there's no MTIME  |
   | zmedico | attribute.                                                   |
   |---------+--------------------------------------------------------------|
   | 6586    | Update /Packages as each package is built (MD5 is done here  |
   | zmedico | since it won't hurt performance).                            |
   |---------+--------------------------------------------------------------|
   | 6587    | Lock $PKGDIR/Packages during population so that it won't get |
   | zmedico | out of sync if another process updates it.                   |
   |---------+--------------------------------------------------------------|
   | 6588    | Store the path of $PKGDIR/Packages as                        |
   | zmedico | binarytree._pkgindex_file.                                   |
   |---------+--------------------------------------------------------------|
   | 6589    | Lock the Packages index while it's being updated with a      |
   | zmedico | packages that was just built.                                |
   |---------+--------------------------------------------------------------|
   | 6590    | Save memory by not holding a reference to the PackageIndex   |
   | zmedico | when it's not being used.                                    |
   +------------------------------------------------------------------------+

svn path=/main/branches/prefix/; revision=6597