adding example runit-style service directory

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

examples/var_service/ifplugd_if/ifplugd_handler

@@ -0,0 +1,15 @@
+#!/bin/sh
+# parameters:
+# $1: interface
+# $2: state
+
+if test -d "/var/service/dhcp_$1"; then
+	if test x"$2" = x"down"; then
+		echo "Downing /var/service/dhcp_$1"
+		sv d "/var/service/dhcp_$1"
+	fi
+	if test x"$2" = x"up"; then
+		echo "Upping /var/service/dhcp_$1"
+		sv u "/var/service/dhcp_$1"
+	fi
+fi

examples/var_service/ifplugd_if/log/run

@@ -0,0 +1,21 @@
+#!/bin/sh
+
+user=logger
+
+logdir="/var/log/service/`(cd ..;basename $PWD)`"
+mkdir -p "$logdir" 2>/dev/null
+chown -R "$user": "$logdir"
+chmod -R go-rwxst,u+rwX "$logdir"
+rm logdir
+ln -s "$logdir" logdir
+
+# make this dir accessible to logger
+chmod a+rX .
+
+exec >/dev/null
+exec 2>&1
+exec \
+env - PATH="$PATH" \
+softlimit \
+setuidgid "$user" \
+svlogd -tt "$logdir"

examples/var_service/ifplugd_if/p_log

@@ -0,0 +1,4 @@
+#!/bin/sh
+
+cd log/logdir || exit 1
+cat @* current | $PAGER

examples/var_service/ifplugd_if/run

@@ -0,0 +1,32 @@
+#!/bin/sh
+
+exec 2>&1
+exec </dev/null
+
+pwd="$PWD"
+
+if="${PWD##*/ifplugd_}"
+
+echo "* Starting ifplugd [$$]"
+exec \
+env - PATH="$PATH" \
+softlimit \
+setuidgid root \
+ifplugd -apq -n -s -i "$if" -r "$pwd/ifplugd_handler"
+
+#-n       Do not daemonize
+#-s       Do not log to syslog
+#-i IFACE Interface
+#-f/-F    Treat link detection error as link down/link up (otherwise exit on error)
+#-a       Do not up interface automatically
+#-M       Monitor creation/destruction of interface (otherwise it must exist)
+#-r PROG  Script to run
+#-x ARG   Extra argument for script
+#-I       Dont exit on nonzero exit code from script
+#-p       Dont run script on daemon startup
+#-q       Dont run script on daemon quit
+#-l       Run script on startup even if no cable is detected
+#-t SECS  Poll time in seconds
+#-u SECS  Delay before running script after link up
+#-d SECS  Delay after link down
+#-m MODE  API mode (mii, priv, ethtool, wlan, auto)

examples/var_service/ifplugd_if/w_log

@@ -0,0 +1,4 @@
+#!/bin/sh
+
+cd log/logdir || exit 1
+watch -n2 'w=`ttysize w`; h=`ttysize h`; tail -$((h-3)) current 2>&1 | cut -b0-$((w-2))'