Split /etc/login.defs into its own binary package

Closes: #1074394

debian/control

@@ -62,12 +62,23 @@ Conflicts:
  python-4suite (<< 0.99cvs20060405-1)
 Replaces:
  hurd (<< 20140206~) [hurd-any]
+Pre-Depends:
+ login.defs (>= 1:4.16.0-1~)
 Description: system login tools
  This package provides support for console-based logins and for
  changing effective user or group IDs, including:
   * login, the program that invokes a user shell on a virtual terminal;
   * nologin, a dummy shell for disabled user accounts;
 
+Package: login.defs
+Architecture: all
+Multi-Arch: foreign
+Replaces:
+ login (<< 1:4.16.0-1~)
+Description: system user management configuration
+ This package provides the login.defs configuration file,
+ used by otherwise unrelated tools managing system users.
+
 Package: uidmap
 Architecture: any
 Multi-Arch: foreign

debian/login.defs.install

@@ -0,0 +1 @@
+debian/config/login.defs etc

debian/login.defs.postinst

@@ -0,0 +1,26 @@
+#!/bin/sh
+
+set -e
+
+_adopt_conffile() {
+    conffile=$1
+    pkg=$2
+
+    [ -f ${conffile}.dpkg-bak ] || return 0
+
+    md5sum="$(md5sum ${conffile} | sed -e 's/ .*//')"
+    old_md5sum="$(dpkg-query -W -f='${Conffiles}' $pkg | \
+                        sed -n -e "\' ${conffile} ' { s/ obsolete$//; s/.* //; p }")"
+    # On new installs, if the conffile was preserved on upgrade by
+    # dpkg-maintscript helper, copy it back if the new file has not been
+    # modified yet
+    if [ "$md5sum" = "$old_md5sum" ]; then
+        mv ${conffile}.dpkg-bak ${conffile}
+    fi
+}
+
+if [ "$1" = configure ] && [ -z "$2" ]; then
+    _adopt_conffile /etc/login.defs login.defs
+fi
+
+#DEBHELPER#

debian/login.install

@@ -1,5 +1,4 @@
 bin/login usr/bin
-debian/login.defs etc
 sbin/nologin usr/sbin
 usr/bin/newgrp
 usr/share/locale/*/LC_MESSAGES/shadow.mo

debian/login.maintscript

@@ -1 +1,2 @@
 rm_conffile /etc/securetty 1:4.7-1~
+rm_conffile /etc/login.defs 1:4.16.0-1~