path: root/dhcpcd-run-hooks.in

#!/bin/sh
# dhcpcd client configuration script 

# Handy variables and functions for our hooks to use
from=from
signature_base="# Generated by dhcpcd"
signature="$signature_base $from $interface"
signature_base_end="# End of dhcpcd"
signature_end="$signature_base_end $from $interface"
state_dir=/var/run/dhcpcd

# Ensure that all arguments are unique
uniqify()
{
	local result= i=
	for i; do
		case " $result " in
			*" $i "*);;
			*) result="$result $i";;
		esac
	done
	echo "${result# *}"
}

# List interface config files in a dir
# If dhcpcd is running as a single instance then it will have a list of
# interfaces in the preferred order.
# Otherwise we just use what we have.
list_interfaces()
{
	local i= x= ifaces=
	for i in $interface_order; do
		[ -e "$1/$i" ] && ifaces="$ifaces${ifaces:+ }$i"
	done
	for x in "$1"/*; do
		[ -e "$x" ] || continue
		for i in $interface_order; do
			if [ $i = "${x##*/}" ]; then
				unset x
				break
			fi
		done
		[ -n "$x" ] && ifaces="$ifaces${ifaces:+ }${x##*/}"
	done
	echo "$ifaces"
}

# We normally use sed to extract values using a key from a list of files
# but sed may not always be available at the time.
key_get_value()
{
	local key=$1 value= x= line=

	shift
	if type sed >/dev/null 2>&1; then
		sed -n "s/^${key}//p" $@
	else
		for x; do
			while read line; do
				case "$line" in
				"$key"*) echo "${line##$key}";;
				esac
			done < "$x"
		done
	fi
}

# We normally use sed to remove markers from a configuration file
# but sed may not always be available at the time.
remove_markers()
{
	local m1=$1 m2=$2 x= line= in_marker=0

	shift; shift
	if type sed >/dev/null 2>&1; then
		sed "/^$m1/,/^$m2/d" $@
	else
		for x; do
			while read line; do
				case "$line" in
				"$m1"*) in_marker=1;;
				"$m2"*) in_marker=0;;
				*) [ $in_marker = 0 ] && echo "$line";;
				esac
			done < "$x"
		done
	fi
}

# Compare two files
# If different, replace first with second otherwise remove second
change_file()
{
	if type cmp >/dev/null 2>&1; then
		cmp -s "$1" "$2"
	elif type diff >/dev/null 2>&1; then
		diff -q "$1" "$2" >/dev/null
	else
		# Hopefully we're only working on small text files ...
		[ "$(cat "$1")" = "$(cat "$2")" ]
	fi
	if [ $? -eq 0 ]; then
		rm -f "$2"
		return 1
	fi
	cat "$2" > "$1"
	rm -f "$2"
	return 0
}

# Save a config file
save_conf()
{
	if [ -f "$1" ]; then
		rm -f "$1-pre.$interface"
		cat "$1" > "$1-pre.$interface"
	fi
}

# Restore a config file
restore_conf()
{
	[ -f "$1-pre.$interface" ] || return 1
	cat "$1-pre.$interface" > "$1"
	rm -f "$1-pre.$interface"
}


# We source each script into this one so that scripts run earlier can
# remove variables from the environment so later scripts don't see them.
# Thus, the user can create their dhcpcd.enter/exit-hook script to configure
# /etc/resolv.conf how they want and stop the system scripts ever updating it.
for hook in \
	@SYSCONFDIR@/dhcpcd.enter-hook \
	@HOOKDIR@/* \
	@SYSCONFDIR@/dhcpcd.exit-hook
do
	for skip in $skip_hooks; do
		case "$hook" in
			*/"$skip")			continue 2;;
			*/[0-9][0-9]"-$skip")		continue 2;;
			*/[0-9][0-9]"-$skip.sh")	continue 2;;
		esac
	done
	if [ -f "$hook" ]; then
		. "$hook"
	fi
done