From 3492de2a4b737a5691f271c81818de45f54e3c20 Mon Sep 17 00:00:00 2001
From: Willy Tarreau <w@1wt.eu>
Date: Wed, 7 Sep 2016 15:57:50 +0200
Subject: scripts/save-etc: add option "-d" to emit a diff vs factory config

It's been missing for a long time to be able to emit a diff of the
configuration compared to the factory config. This is now done with
"save-etc -d". It also supports dumping to a file with -o.
---
 scripts/save-etc | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/scripts/save-etc b/scripts/save-etc
index 1f5cf34..911417f 100755
--- a/scripts/save-etc
+++ b/scripts/save-etc
@@ -17,6 +17,7 @@ FORCE=0
 VERBOSE=0
 STDOUT=0
 QUIET=0
+DIFF=0
 LIST=0
 TOFILE=0
 TONET=0
@@ -117,6 +118,16 @@ archive_etc() {
     | gzip -c9
 }
 
+# emits a diff between factory and /etc on stdout. Note that tar is only used
+# to comply with ignore-files here.
+diff_etc() {
+  flx check --ignore-dot --ignore-link --ignore-date $REFERENCE=etc /etc=etc \
+    | awk '/^[+>]/ { print $9 }' \
+    | tar -C / -T - --one-file-system --numeric-owner --no-recursion --exclude-from $EXCLUDE -cf - \
+    | tar tf - \
+    | while read; do diff -puN ${REFERENCE}${REPLY#etc} /etc${REPLY#etc}; done
+}
+
 # creates a secure empty temporary directory and returns its full path name.
 # Returns 0 if it succeeds, with the name on stdout, otherwise returns 1.
 mkstemp() {
@@ -165,6 +176,7 @@ while [ $# -gt 0 ]; do
   elif [ ".$1" = ".-q" ]; then QUIET=1
   elif [ ".$1" = ".-s" ]; then STDOUT=1
   elif [ ".$1" = ".-l" ]; then LIST=1
+  elif [ ".$1" = ".-d" ]; then DIFF=1
   elif [ ".$1" = ".-o" -a -n "$2" ]; then
     TOFILE=1
     OUTFILE="$2"
@@ -178,6 +190,7 @@ while [ $# -gt 0 ]; do
     echo "Unknown argument: $1"
     echo "Valid options are :"
     echo "  -f : force write even if up-to-date ;"
+    echo "  -d : only emit a diff from factory config ;"
     echo "  -v : only check whether files have been modified ;"
     echo "  -l : (with -v) use listing output format (no headers) ;"
     echo "  -q : suppress any message. With -v, return non-0 if unsaved changes exist ;"
@@ -217,6 +230,15 @@ if [ $VERBOSE -eq 1 ]; then
   fi
 fi
 
+if [ $DIFF -eq 1 ]; then
+  if [ $TOFILE -eq 1 ]; then
+    diff_etc > "$OUTFILE"
+  else
+    diff_etc
+  fi
+  exit 0
+fi
+
 if [ $FORCE -eq 0 -a $STDOUT -eq 0 -a $TOFILE -eq 0 -a $TONET -eq 0 -a -e $FILE ] && \
   [ $(list_changes | wc -l) -eq 0 ]; then
   [ $QUIET -eq 0 ] && echo "Nothing changed since last backup. Use '-f' if you want to force."
-- 
1.7.12.1