Merge branch 'master' of simonslx:openslx-ng/tm-scripts

1 files changed, 210 insertions, 0 deletions

diff --git a/remote/includes/chroot.inc b/remote/includes/chroot.inc
new file mode 100644
index 00000000..48ad39d3
--- /dev/null
+++ b/remote/includes/chroot.inc
@@ -0,0 +1,210 @@
+# -----------------------------------------------------------------------------
+#
+# Copyright (c) 2014 - OpenSLX GmbH
+#
+# This program is free software distributed under the GPL version 2.
+# See http://openslx.org/COPYING
+#
+# If you have any feedback please consult http://openslx.org/feedback and
+# send your suggestions, praise, or complaints to feedback@openslx.org
+#
+# General information about OpenSLX can be found at http://openslx.org/
+# -----------------------------------------------------------------------------
+#
+#			Common functions for chrooting
+#
+# -----------------------------------------------------------------------------
+
+CHROOT_TEMPDIR="${ROOT_DIR}/remote/chroot.tmp"
+CHROOT_MOUNTDIR="${CHROOT_TEMPDIR}/rootmount"
+CHROOT_BINDDIR="${CHROOT_TEMPDIR}/rootbind"
+CHROOT_LOWERDIR="/"
+CHROOT_BINDMOUNTS="/dev /proc /sys /run"
+
+# Helper function to setup the directory structure
+chroot_prepare_dirs() {
+	# first check if CHROOT_TEMPDIR exists
+	if [ -d "${CHROOT_TEMPDIR}" ]; then
+		# try to umount and rmdir CHROOT_MOUNTDIR
+		umount "${CHROOT_MOUNTDIR}" 2>/dev/null
+		rmdir "${CHROOT_MOUNTDIR}" || perror "Could not remove '${CHROOT_MOUNTDIR}', meaning it has stuff in it. Aborting..."
+
+		# try to umount and rmdir CHROOT_BINDDIR
+		umount "${CHROOT_BINDDIR}" 2>/dev/null
+		rmdir "${CHROOT_BINDDIR}" || perror "Could not remove '${CHROOT_BINDDIR}', meaning it has stuff in it. Aborting..."
+
+		# try to rmdir CHROOT_TEMPDIR
+		rmdir "${CHROOT_TEMPDIR}" || perror "Could not remove '${CHROOT_TEMPDIR}', meaning it has stuff in it. Aborting..."
+	fi
+
+	mkdir -p "${CHROOT_TEMPDIR}"	|| perror "Could not create base directory for mount directories $CHROOT_TEMPDIR."
+	for DIR in "${CHROOT_BINDDIR}" "${CHROOT_MOUNTDIR}"; do
+		mkdir -p "${DIR}"			|| perror "Could not create directory for mount directory $DIR."
+	done
+}
+
+# Helper to mount the overlay structure:
+#	- bind mount system / to CHROOT_BINDDIR and make it read-only
+#	- make an overlay from CHROOT_LOWERDIR CHROOT_UPPERDIR
+#	- bind mount additional pseudo-fs (as given in CHROOT_BINDMOUNTS)
+chroot_prepare_mounts() {
+
+	# first mount / on CHROOT_BINDDIR and remount read-only
+	mount -o bind "${CHROOT_LOWERDIR}" "${CHROOT_BINDDIR}"	|| perror "Could not bind-mount '$CHROOT_LOWERDIR' to '$CHROOT_BINDDIR'."
+	mount -o remount,ro,bind "${CHROOT_BINDDIR}"		|| perror "Could not remount '$CHROOT_BINDDIR' read-only."
+
+	# check that it really is read-only
+	[ "x$(mount | grep -E "^/ on ${CHROOT_BINDDIR}" | grep -v '\(.*ro.*\)')" != "x" ] && perror "'${CHROOT_BINDDIR}' is not read-only! Aborting..."
+
+	# safe, go on to make the overlay
+	mount -t overlayfs overlayfs -o lowerdir="${CHROOT_BINDDIR}",upperdir="${CHROOT_UPPERDIR}" "${CHROOT_MOUNTDIR}"  \
+		|| perror "Could not mount (overlayfs) $CHROOT_LOWERDIR, $CHROOT_UPPERDIR to $CHROOT_BINDDIR."
+
+	# mount pseudo-filesystems
+	for DIR in $CHROOT_BINDMOUNTS; do
+		mount -o bind "${DIR}" "${CHROOT_MOUNTDIR}/${DIR}" \
+			|| perror "Could not bind mount '$DIR' into '$CHROOT_MOUNTDIR/$DIR'."
+	done
+}
+
+# Helper to generate the mighty autoexec.bat
+chroot_gen_autoexec() {
+	# create the script to be automatically executed.
+	cat >"${CHROOT_MOUNTDIR}/autoexec.bat"<<-EOF
+		#!/bin/bash
+		#######################################################
+		#						      #
+		#		    Warning!			      #
+		#						      #
+		#  This	file is only meant to be executed within      #
+		#  the specially chrooted mltk building environment.  # 
+		#						      #
+		#  Do NOT execute it if you are not sure what you do, #
+		#  it may be very harmful if being run in a normal    #
+		#  system environment!				      #
+		#						      #
+		#######################################################
+		echo "chroot started successfully."
+	EOF
+
+	# dump the piped input to it
+	cat >> "${CHROOT_MOUNTDIR}/autoexec.bat"
+
+	# make it executable
+	chmod +x "${CHROOT_MOUNTDIR}/autoexec.bat"
+}
+
+chroot_handle_whiteouts() {
+	local WHITEOUT_LIST="${CHROOT_UPPERDIR}/overlay.whiteout.list"
+	rm -f -- "$WHITEOUT_LIST="
+	#mkdir -p "$(dirname "$WHITEOUT_LIST")" || perror "Could not create $(dirname "$WHITEOUT_LIST")"
+	pdebug "Searching for overlayfs-whiteouts ..."
+	for WHITEOUT in $(find "$CHROOT_UPPERDIR" -lname "(overlay-whiteout)"); do
+		pdebug "Whiteout found: $WHITEOUT"
+		echo "/./${WHITEOUT#$CHROOT_UPPERDIR}" >> "$WHITEOUT_LIST"
+		rm -f -- "$WHITEOUT" || perror "Could not delete whiteout $WHITEOUT!"
+	done
+	pinfo "Whiteout list dumped to '${CHROOT_UPPERDIR}/overlay.whiteout.list'"
+}
+
+###############################################################################
+#
+#				MAIN FUNCTION
+#
+# Main function to be called from the outside
+# Usage:
+#	chroot_run <build_dir> < <code_to_exec_in_chroot>
+#
+# Example:
+#	chroot_run /tmp/chroot_build <<-EOF
+#		echo "This will be executed inside the chroot"
+#	EOF
+#
+# It will run:
+#	- chroot_prepare
+#	- chroot $CHROOT_TEMPDIR/rootmount
+#	- executes $CHROOT_TEMPDIR/rootmount/autoexec.bat
+#	- chroot_cleanup
+chroot_run() {
+	# check args
+	[ $# -eq 1 ] || perror "'chroot_run' requires exactly 1 parameter. Given $#.  Use 'chroot_run <build_dir>'"
+
+	local CHROOT_UPPERDIR="$1"
+	mkdir -p "$1" 
+
+	# first prepare the dir structure
+	chroot_prepare_dirs || perror "'chroot_prepare_dirs' failed with $?."
+	chroot_prepare_mounts || perror "'chroot_prepare_mounts' failed with $?."
+
+	# generate the code to be executed when chroot'ing
+	chroot_gen_autoexec || perror "'chroot_gen_autoexec' failed with $?."
+
+	# do the chroot
+	exec 0>&8		# This redirection is used for debugging within a chroot
+	chroot --userspec root:root "${CHROOT_MOUNTDIR}" /autoexec.bat
+	local RET=$?
+	if [ "$RET" -eq 0 ]; then
+		pinfo "chroot executed '${CHROOT_MOUNTDIR}/autoexec.bat' succeeded."
+	else
+		perror "Failed to run '$CHROOT_MOUNTDIR/autoexec.bat' inside the chroot to '$CHROOT_MOUNTDIR' with error code: $RET"
+	fi
+
+	# handle whiteouts
+	chroot_handle_whiteouts || perror "'chroot_handle_whiteouts' failed with error code: $?"
+
+	# finally cleanup all the mounting stuff we did previously
+	chroot_cleanup_mounts			|| perror "'chroot_cleanup' failed with $?."
+}
+
+###############################################################################
+#
+#				CLEANUP FUNCTIONS
+#
+# Helper to check if the given path is mounted
+chroot_check_mount_point() {
+	[ "$#" -eq 1 ] || perror "'chroot_check_mount_point' called with $# arguements, only 1 accepted."
+	local MOUNT="$1"	
+	if [ "x$(mount | grep "$(readlink -f $MOUNT)")" != "x" ]; then
+		# still mounted
+		pdebug "'$MOUNT' is mounted!"
+		return 1
+	else
+		pdebug "'$MOUNT' is not mounted."
+		return 0
+	fi
+}
+
+# Helper to umount the given path
+chroot_umount() {
+	[ "$#" -eq 1 ] || perror "'chroot_umount' called with $# arguments, only 1 accepted."
+	local MOUNT="$1"
+
+	# check if MOUNT is mounted
+	if ! chroot_check_mount_point "${MOUNT}"; then
+		# still mounted
+		if umount -l "${MOUNT}"; then
+			pdebug "Successfully umounted '${MOUNT}'."
+		else
+			pwarning "Could not umount '${MOUNT}'! Trying again..."
+			# now it gets ugly
+			for i in `seq 1 5`; do
+				umount -l "${MOUNT}" && return 0
+			done
+			perror "Could not umount '${MOUNT}' after 5 tries! This shouldn't happen. Check your scripts."
+		fi
+	else
+		pdebug "'${MOUNT}' is not mounted."
+	fi
+
+	# better be safe than sorry
+	chroot_check_mount_point "$MOUNT" || perror "'$MOUNT' is still mounted, exiting before something bad happens..."
+}
+
+# Helper to cleanup the temporary mounts
+chroot_cleanup_mounts() {
+	for DIR in $CHROOT_BINDMOUNTS; do
+		chroot_umount "${CHROOT_MOUNTDIR}/${DIR}"
+	done
+	chroot_umount "${CHROOT_MOUNTDIR}"
+	chroot_umount "${CHROOT_BINDDIR}"
+}