[PATCH 3/3] random.sh: random timing for netmon communication

[Tim Niemeyer]

Signed-off-by: Tim Niemeyer <tim.niemeyer at mastersword.de>
---

 bsp/default/root_file_system/etc/crontabs/root |  3 ++-
 bsp/default/root_file_system/etc/random.sh     | 16 ++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100755 bsp/default/root_file_system/etc/random.sh

diff --git a/bsp/default/root_file_system/etc/crontabs/root b/bsp/default/root_file_system/etc/crontabs/root
index 7e45014..6fac8ce 100644
--- a/bsp/default/root_file_system/etc/crontabs/root
+++ b/bsp/default/root_file_system/etc/crontabs/root
@@ -1,2 +1,3 @@
-*/5 * * * *	sh /etc/fastdstart.sh; sh /etc/nodewatcher.sh; sh /etc/configurator.sh; /etc/syncHostname.sh
+*/5 * * * *	sleep $(/etc/random.sh 0 29); sh /etc/fastdstart.sh; sh /etc/nodewatcher.sh; sleep $(/etc/random 0 209); sh /etc/configurator.sh
+0/30 * * * * sleep $(/etc/random.sh 0 1790); /etc/syncHostname.sh
 */1 * * * * /usr/sbin/batctl gw off; sleep 1; /usr/sbin/batctl gw client
diff --git a/bsp/default/root_file_system/etc/random.sh b/bsp/default/root_file_system/etc/random.sh
new file mode 100755
index 0000000..8f11470
--- /dev/null
+++ b/bsp/default/root_file_system/etc/random.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+# Freifunk Franken Random Number Script
+# Tim Niemeyer
+# 29.11.2015
+# License GPLv2
+
+FROM=${1:-0}
+UNTIL=${2:-100}
+
+diff=$(( UNTIL - FROM ))
+numbers=$(( $(echo $diff | wc -c) -1 ))
+
+rand=$(</dev/urandom tr -dc 0-9 | head -c $numbers | sed -e 's/^0*//g')
+
+echo $(( (rand % diff) + FROM ))
+
-- 
2.1.4