From 790b7ec9f9a5e42b08d730a5218bbd6d7624a69c Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sun, 10 Jun 2012 14:51:54 +0000
Subject: [PATCH] Some work on making things faster.

No functional changes.
---
 functions.util | 47 ++++++++++++++++++++++++++++++-----------------
 1 file changed, 30 insertions(+), 17 deletions(-)

diff --git a/functions.util b/functions.util
index 694c7a40..0b646f7d 100644
--- a/functions.util
+++ b/functions.util
@@ -75,6 +75,12 @@ function basename() {
 	echo "${1##*/}"
 }
 
+function touch() {
+	local file=${1}
+
+	: > ${file}
+}
+
 function enabled() {
 	local param=${1}
 
@@ -82,31 +88,38 @@ function enabled() {
 }
 
 function mac_generate() {
-	local mac=()
+	# Get a bunch of random hex digits
+	# and remove all dashes from the input.
+	local random=$(</proc/sys/kernel/random/uuid)
+	random=${random//-/}
+	assert isset random
+
+	local output
+
+	local i o
 	for i in $(seq 0 5); do
-		mac[i]="$(uuid)"
-		mac[i]="0x${mac[i]:0:2}"
-	done
+		o="0x${random:0:2}"
+		random="${random:2:${#random}}"
 
-	# Remove multicast bit
-	# and set address is software assigned
-	# XXX must doublecheck if this works
-	mac[0]=$((mac[0] & 0xfe))
-	mac[0]=$((mac[0] | 0x02))
+		case "${i}" in
+			0)
+				# Remove multicast bit
+				# and set address is software assigned
+				o=$(( ${o} & 0xfe ))
+				o=$(( ${o} | 0x02 ))
 
-	local output
-	for i in ${mac[*]}; do
-		if [ -n "${output}" ]; then
-			output="${output}:"
-		fi
-	
-		output="${output}$(printf "%02x" ${i})"
+				printf -v output "%02x" "${o}"
+				;;
+			*)
+				printf -v output "%s:%02x" "${output}" "${o}"
+				;;
+		esac
 	done
 
 	# Check if output is valid
 	assert mac_is_valid ${output}
 
-	echo ${output}
+	echo "${output}"
 }
 
 function mac_format() {
-- 
2.47.3