alfred: workaround race condition when batmanif is not ready at boot time

Wait up to 30 seconds during init.d script on boot, so that batmanif can
come up. If the timeout is reached, the init.d script refuses to start
alfred and related daemons.

This prevents an alfred crash when it would start during early boot, before
batmanif is available. Instead, alfred is started as soon as batmanif appears,
if that happens during the 30-second window.

Signed-off-by: Gui Iribarren <gui@altermundi.net>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

alfred/Makefile

@@ -12,7 +12,7 @@ include $(TOPDIR)/rules.mk
 #
 PKG_NAME:=alfred
 PKG_VERSION:=2013.4.0
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 PKG_MD5SUM:=3891697e127b1037cfc9349fd96e9993
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz

alfred/files/alfred.init

@@ -16,6 +16,7 @@ pid_file_alfred="/var/run/alfred.pid"
 pid_file_vis="/var/run/batadv-vis.pid"
 enable=0
 vis_enable=0
+batmanif=""
 SERVICE_DAEMONIZE=1
 SERVICE_WRITE_PID=1
 
@@ -23,7 +24,7 @@ alfred_start()
 {
 	local args=""
 	local section="$1"
-	local disabled interface mode batmanif
+	local disabled interface mode
 
 	# check if section is disabled
 	config_get_bool disabled "$section" disabled 0
@@ -62,6 +63,21 @@ start()
 	if [ "$enable" = "0" ]; then
 		exit 0
 	fi
+
+	mesh_dir="/sys/class/net/$batmanif/mesh/"
+	if ! [ -d "$mesh_dir" ] ; then
+		timeout=30
+		echo "${initscript}: waiting $timeout secs for $batmanif interface..."
+		for i in $(seq $timeout); do
+			sleep 1
+			[ -d "$mesh_dir" ] && break
+			if [ $i == $timeout ] ; then
+				echo "${initscript}: $batmanif not detected, alfred not starting."
+				exit 1
+			fi
+		done
+	fi
+
 	echo "${initscript}: starting alfred"
 	SERVICE_PID_FILE="$pid_file_alfred"
 	service_start /usr/sbin/alfred ${alfred_args}