nodewatcher: Change mechanism for client device detection

This is simpler than the previous approach and does not rely
on parsing.

This fixes:
- Interfaces being accounted for multiple times for certain
  devices
- Errors when output of bridge function changes (as with the
  current OpenWrt master)

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Reviewed-by: Tim Niemeyer <tim@tn-x.org>
Reviewed-by: Fabian Bläse <fabian@blaese.de>

src/packages/fff/fff-nodewatcher/Makefile

@@ -1,7 +1,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=fff-nodewatcher
-PKG_VERSION:=47
+PKG_VERSION:=48
 PKG_RELEASE:=1
 
 PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME)

src/packages/fff/fff-nodewatcher/files/usr/sbin/nodewatcher

@@ -2,7 +2,7 @@
 # Netmon Nodewatcher (C) 2010-2012 Freifunk Oldenburg
 # License; GPL v3
 
-SCRIPT_VERSION="47"
+SCRIPT_VERSION="48"
 
 test -f /tmp/started || exit
 
@@ -260,7 +260,7 @@ crawl() {
     #CLIENTS
     client_count=0
     dataclient=""
-    CLIENT_INTERFACES=$(bridge link | awk '$2 !~/^bat/{ printf $2" " }')
+    CLIENT_INTERFACES=$(ls "/sys/class/net/$MESH_INTERFACE/brif" | grep -v '^bat')
     for clientif in ${CLIENT_INTERFACES}; do
         local cc=$(bridge fdb show br "$MESH_INTERFACE" brport "$clientif" | grep -v self | grep -v permanent -c)
         client_count=$((client_count + cc))