locmaint: improve handling of obsolete conffiles

1 files changed, 27 insertions, 4 deletions

diff --git a/bin/locmaint b/bin/locmaint
index c182ace0..98a1e2f4 100755
--- a/bin/locmaint
+++ b/bin/locmaint
@@ -114,6 +114,25 @@ for (getpwuid($<) . '@' . `hostname -f`) {
     }
 }
 
+# List of files which dpkg considers obsolete, but where deleting the
+# conffile and reinstalling its package does not resolve the problem
+# or is not what should be done.  One case in which doing that is not
+# the correct fix is when conffiles move between packages.
+#
+# It's a bug in the package if
+# - there are obsolete conffiles which the local administrator has
+#   never modified
+# - regardless of whether the file has been modified by the local
+#   administrator, deleting the conffile and reinstalling its package
+#   does not get clear the entry from the list of obsolete conffiles.
+#
+# When adding an entry to this list, see if a bug needs to be
+# reported, and record the Debian release in which the bug was seen,
+# so entries can be removed at some point
+our %known_bad_obsolete_conffiles = (
+    "/etc/this_is_a_sample_entry" => undef,    # buster
+);
+
 # CODE -- no more edit me
 
 exit main();
@@ -561,20 +580,24 @@ sub do_sysmaint {
         } else {
             my @fields = split ' ';
             push @{$obsolete_conffiles{$curr_pkg}}, $fields[0]
-              if $fields[$#fields] eq "obsolete";
+              if $fields[$#fields] eq "obsolete"
+              and not exists $known_bad_obsolete_conffiles{$fields[0]};
         }
     }
     unless (keys %obsolete_conffiles == 0) {
         my @all_obsolete_conffiles;
-        say_bold("Obsolete conffiles:");
+        say_bold "Obsolete conffiles:\n";
         foreach my $pkg (keys %obsolete_conffiles) {
             foreach my $file (@{$obsolete_conffiles{$pkg}}) {
                 print "  $pkg\t$file\n";
                 push @all_obsolete_conffiles, $file;
             }
         }
-        if (prompt_yn
-            ("Fix by deleting each conffile and reinstalling its package (is not the right fix if conffile has moved between packages)?")) {
+        print "\nPlease report bugs if these files unedited by the local administrator,\n"
+         . "and then, can attempt to fix by deleting each conffile and reinstalling\n"
+         . "its package -- but note that this is not the right fix if the conffile has\n"
+         . "moved between packages.\n\n";
+        if (prompt_yn "Attempt the fix?") {
             system as_root("rm @all_obsolete_conffiles");
             system as_root("apt-get install -y --reinstall "
                            . join(' ', keys %obsolete_conffiles));