opensde-nopast/lib/overlay/overlay-functions.in

# --- SDE-COPYRIGHT-NOTE-BEGIN ---
# This copyright note is auto-generated by ./scripts/Create-CopyPatch.
#
# Filename: lib/overlay/overlay-functions.in
# Copyright (C) 2007 - 2008 The OpenSDE Project
#
# More information can be found in the files COPYING and README.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License. A copy of the
# GNU General Public License can be found in the file COPYING.
# --- SDE-COPYRIGHT-NOTE-END ---

# returns the type of overlay based on the extension of the overlay file
#
overlay_get_type()
{
	local ext="${1##*.}"

	case "$ext" in
		sh|exec)	echo "exec"	;;
		txt|patch|ln)	echo "$ext"	;;
		*)	# and skip anything else
			;;
	esac
}

# returns the name of a target file based on the name overlay file
#
overlay_get_filename()
{
	local filename="${1##*/}"; filename="${filename%.*}"

	# rock_substitute will add a leading / for most translations
	echo "${filename}" | tr '_%' '/_' | rock_substitute | sed -e 's,^/,,'
}

# apply an overlay dir
overlay_apply() {
	local overlaydir="$1" rootfs="${2:-$root}"
	local file= source= target= ext=
	local type= mode= ref= targetdir=
	local patchopt="-p1 --no-backup-if-mismatch -N"

	for file in "$overlaydir"/*; do
		# only consider known overlay types
		type=$( overlay_get_type "$file" )
		[ -n "$type" ] || continue

		# full filename of the target file, and it's directory
		target=$( overlay_get_filename "$file" )
		targetdir="$rootfs/$target"; targetdir="${targetdir%/*}"

		# final adjustments based on the type
		case "$type" in
			exec)	mode=0755 ;;
			*)	mode=0644 ;;
		esac

		# and finally inject the file
		case "$type" in
			exec|txt)
				echo_status "injecting $target ($type)"
				mkdir -p "$targetdir"
				[ ! -L "$rootfs/$target" ] || rm -f "$rootfs/$target"
				cat "$file" | rock_substitute > "$rootfs/$target"
				chmod $mode "$rootfs/$target"
				;;
			ln)	ref=$( cat "$file" | rock_substitute )
				echo_status "injecting $target -> $ref"
				mkdir -p "$targetdir"
				ln -snf "$ref" "$rootfs/$target"
				;;
			patch)
				echo_status "$(patch $patchopt \
					-d "${rootfs}" 2>&1 < $file )"
				;;
		esac
	done
}