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 - 2012 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 "$ext" in
		sh|exec)	echo "exec"	;;
		txt|patch|ln|bin|rm)
				echo "$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= rootfs=
	local file= source= target= xtarget= ext=
	local type= mode= ref= targetdir=
	local patchopt="-p1 --no-backup-if-mismatch -N"
	local overwrite=yes echo_status=echo_status

	while [ $# -gt 0 ]; do
		case "$1" in
		-n)	overwrite= ;;
		-q)	echo_status=echo ;;
		--)	shift; break ;;
		-*)	echo_warning "overlay_apply: $1: invalid option." ;;
		*)	break ;;
		esac
		shift
	done

	overlaydir="$1" rootfs="${2:-$root}"

	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" )
		xtarget="$rootfs/$target" targetdir="${xtarget%/*}"

		if [ -L "$xtarget" -o -e "$xtarget" ]; then
			if [ "$type" != rm -a "$overwrite" != yes ]; then
				$echo_status "skipping $target ($type)"
				continue
			fi

			if [ "$type" = patch ]; then
				:
			elif [ ! -d "$xtarget/" ]; then
				rm -f "$xtarget"
			else
				rm -rf "$xtarget"
			fi
		fi

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

		[ "$type" = "patch" ] || mkdir -p "$targetdir"

		# and finally inject the file
		case "$type" in
			bin|exec|txt)
				$echo_status "injecting $target ($type)"
				if [ "$type" = bin ]; then
					cp "$file" "$xtarget"
				else
					cat "$file" | rock_substitute > "$xtarget"
				fi
				chmod $mode "$xtarget"
				;;
			ln)	ref=$( cat "$file" | rock_substitute )
				$echo_status "injecting $target -> $ref"
				ln -snf "$ref" "$xtarget"
				;;
			rm)
				$echo_status "removing $target"
				;;
			patch)
				$echo_status "overlay: patching $target"
				rock_substitute "$file" | patch $patchopt "$xtarget"
				;;
		esac

		# flist hackery... needed?
		case "$type" in
		patch|rm) ;;
		*) add_flist "$xtarget" ;;
		esac
	done
}