From 172555b16331aaa411d3cdac7625e5d0d444d793 Mon Sep 17 00:00:00 2001
From: Michael Prokop <mika@grml.org>
Date: Mon, 21 Oct 2013 09:23:18 +0200
Subject: [PATCH] Support overriding configuration via environment variables

Inspired by https://github.com/grml/grml-debootstrap/pull/10,
thanks adrelanos
---
 grml-debootstrap | 52 ++++++++++++++++++++++++++--------------------------
 1 file changed, 26 insertions(+), 26 deletions(-)

diff --git a/grml-debootstrap b/grml-debootstrap
index fc12e7c..c87c9b6 100755
--- a/grml-debootstrap
+++ b/grml-debootstrap
@@ -14,32 +14,32 @@ VERSION="${VERSION:-unknown}"
 MNTPOINT="/mnt/debootstrap.$$"
 
 # defaults
-CHROOT_SCRIPTS='yes'
-CONFFILES='/etc/debootstrap'
-DEBCONF='yes'
-DEBIAN_FRONTEND='noninteractive'
-DEBOOTSTRAP='debootstrap'
-DEFAULT_LOCALES='en_US.UTF-8'
-EXTRAPACKAGES='yes'
-FALLBACK_MIRROR='http://http.debian.net/debian'
-FORCE=''
-HOSTNAME='grml'
-INITRD='yes'
-INSTALL_NOTES='/etc/debootstrap/install_notes'
-LOCALES='yes'
-MIRROR="$FALLBACK_MIRROR"
-MKFS='mkfs.ext3'
-PACKAGES='yes'
-PRE_SCRIPTS='yes'
-RECONFIGURE='console-data'
-RELEASE='wheezy'
-RM_APTCACHE='yes'
-SCRIPTS='yes'
-SECURE='yes'
-TIMEZONE='Europe/Vienna'
-TUNE2FS='tune2fs -c0 -i0'
-UPGRADE_SYSTEM='yes'
-VMSIZE="2G"
+[ -n "$CHROOT_SCRIPTS"] || CHROOT_SCRIPTS='yes'
+[ -n "$CONFFILES"] || CONFFILES='/etc/debootstrap'
+[ -n "$DEBCONF"] || DEBCONF='yes'
+[ -n "$DEBIAN_FRONTEND"] || DEBIAN_FRONTEND='noninteractive'
+[ -n "$DEBOOTSTRAP"] || DEBOOTSTRAP='debootstrap'
+[ -n "$DEFAULT_LOCALES"] || DEFAULT_LOCALES='en_US.UTF-8'
+[ -n "$EXTRAPACKAGES"] || EXTRAPACKAGES='yes'
+[ -n "$FALLBACK_MIRROR"] || FALLBACK_MIRROR='http://http.debian.net/debian'
+[ -n "$FORCE"] || FORCE=''
+[ -n "$HOSTNAME"] || HOSTNAME='grml'
+[ -n "$INITRD"] || INITRD='yes'
+[ -n "$INSTALL_NOTES"] || INSTALL_NOTES='/etc/debootstrap/install_notes'
+[ -n "$LOCALES"] || LOCALES='yes'
+[ -n "$MIRROR"] || MIRROR="$FALLBACK_MIRROR"
+[ -n "$MKFS"] || MKFS='mkfs.ext3'
+[ -n "$PACKAGES"] || PACKAGES='yes'
+[ -n "$PRE_SCRIPTS"] || PRE_SCRIPTS='yes'
+[ -n "$RECONFIGURE"] || RECONFIGURE='console-data'
+[ -n "$RELEASE"] || RELEASE='wheezy'
+[ -n "$RM_APTCACHE"] || RM_APTCACHE='yes'
+[ -n "$SCRIPTS"] || SCRIPTS='yes'
+[ -n "$SECURE"] || SECURE='yes'
+[ -n "$TIMEZONE"] || TIMEZONE='Europe/Vienna'
+[ -n "$TUNE2FS"] || TUNE2FS='tune2fs -c0 -i0'
+[ -n "$UPGRADE_SYSTEM"] || UPGRADE_SYSTEM='yes'
+[ -n "$VMSIZE"] || VMSIZE="2G"
 
 # inside the chroot system locales might not be available, so use minimum:
 export LANG=C
-- 
2.1.4