Add usage info, and command line arguments.

diff --git a/etcdiff.sh b/etcdiff.sh
index 3014c4b..4ee0212 100755 (executable)
--- a/etcdiff.sh
+++ b/etcdiff.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 #
 # etcdiff (deb-etcdiff?) shows how your current /etc dir
-# diverges from the debian distribution standard one.
+# diverges from the debian default one.
 #
 # Copyright (C) 2008,2009,2010 Antonio Ospite <ospite@studenti.unina.it>
 # License: GPLv2 or later
@@ -18,34 +18,56 @@ TEMPDIR=${BASEDIR}/temp
 CACHEDIR=${BASEDIR}/cache
 REPORTDIR=${BASEDIR}/reports
 
+usage()
+{
+  echo "usage: $0 <file|package|system> [<file name>|<package name>]
+
+etcdiff shows how your /etc dir differs from the debian default one
+
+etcdiff by explicit file list:
+    FILES='/etc/sysctl.conf /etc/updatedb.conf'
+    for file in \$FILES;
+    do
+      $0 file \$file
+    done
+
+etcdiff bycommand generated file list
+    FILES=\$(find /etc/apache2 -type f -perm /o+r | grep -v '.dpkg-')
+    for file in \$FILES;
+    do
+      $0 file \$file
+    done
+
+etcdiff by package name
+    $0 package cherokee
+    $0 package mlocate
+    $0 package apache2-doc
+    $0 package apache2.2-common
+    $0 package libapache2-mod-php5
+    $0 package hostapd
+
+etcdiff the whole /etc system directory
+    $0 system
+"
+}
+
 rm $PROMPT_RM -rf $TEMPDIR   && mkdir $TEMPDIR
 rm $PROMPT_RM -rf $CACHEDIR  && mkdir $CACHEDIR
 rm $PROMPT_RM -rf $REPORTDIR && mkdir $REPORTDIR
 
 . $BASEDIR/etcdiff.include
 
-# Examples of file query
-
-# by explicit file list
-#FILES="/etc/sysctl.conf /etc/updatedb.conf"
-#for file in $FILES;
-#do
-#  etcdiff_by_file $file
-#done
-
-# by file list generated by a command
-#FILES=$(find /etc/apache2 -type f -perm /o+r | grep -v '.dpkg-')
-#for file in $FILES;
-#do
-#  etcdiff_by_file $file
-#done
-
-# by package name
-#etcdiff_by_package cherokee
-#etcdiff_by_package mlocate
-#etcdiff_by_package apache2-doc
-#etcdiff_by_package apache2.2-common
-#etcdiff_by_package libapache2-mod-php5
-#etcdiff_by_package hostapd
-
-#etchdiff_system
+case $1 in
+  file)
+    etcdiff_by_file $2
+    ;;
+  package)
+    etcdiff_by_package $2
+    ;;
+  system)
+    etcdiff_system
+    ;;
+  *)
+    usage
+    ;;
+esac