diff options
Diffstat (limited to 'baserock-system-config-sync/baserock-system-config-sync')
| -rwxr-xr-x | baserock-system-config-sync/baserock-system-config-sync | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/baserock-system-config-sync/baserock-system-config-sync b/baserock-system-config-sync/baserock-system-config-sync new file mode 100755 index 0000000..00ceac0 --- /dev/null +++ b/baserock-system-config-sync/baserock-system-config-sync @@ -0,0 +1,216 @@ +#!/bin/sh +# +# Copyright (c) 2013 Codethink Ltd. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License Version 2 as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License along +# with this program; if not, write to the Free Software Foundation, Inc., +# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + +set -eu + + +mounting_script="$(dirname "$0")/../libexec/mount-system-versions-dir" + + +usage() { + echo "Usage: $(basename $0) test V1_DIR VU_DIR V2_DIR VT_DIR" >&2 + echo " $(basename $0) merge NEW_VERSION_LABEL" >&2 + echo " $(basename $0) sync CANONICAL_VERSION_LABEL" >&2 + exit 1 +} + + +die () { + echo $@ >&2 + exit 1 +} + + +merge() { + local vp_dir="$1" # version being processed + local v1_dir="$2" # factory version + local vu_dir="$3" # user modified version + local v2_dir="$4" # unmodified new deployed version + local vt_dir="$5" # target version where the result of the + # merge should be placed + + # use `find "$vp_dir/"*` instead of `find "$vp_dir"` because + # the last one also gives $vp_dir in the list of directories + find "$vp_dir/"* | while read f; do + # strip first component from file name + local stripped_filename=${f#$vp_dir/} + + local vp="$vp_dir/$stripped_filename" + local v1="$v1_dir/$stripped_filename" + local vu="$vu_dir/$stripped_filename" + local v2="$v2_dir/$stripped_filename" + local vt="$vt_dir/$stripped_filename" + + if [ -e "$vt" ]; then + # If the file already exists in the target, + # check if it is of the same kind + vp_type="$(stat -c %F "$vp")" + vt_type="$(stat -c %F "$vt")" + echo "$vp - $vt - $vp_type - $vt_type" >&2 + if [ "$vp_type" != "$vt_type" ]; then + die "found two different types for '$stripped_filename':" \ + "$vp_type and $vt_type" + fi + elif [ -d "$vp" ] && [ ! -h "$vp" ]; then + mkdir "$vt" + elif [ -h "$vp" ]; then + # Discussion: what we want to do about symbolic links? + # I chose a symbolic link in this order of preference: + # Vuser, V2, V1 + if [ -h "$vu" ]; then + cp -a "$vu" "$vt" + elif [ -h "$v2" ]; then + cp -a "$v2" "$vt" + else + cp -a "$v1" "$vt" + fi + elif [ -f "$vp" ]; then + merge_regular_file "$v1" "$vu" "$v2" "$vt" + else + die "ERROR: unexpected error" + fi + done +} + + +merge_regular_file() { + local v1="$1" + local vu="$2" + local v2="$3" + local vt="$4" + # Reference table for merging a regular file + # + # V1 Vuser V2 action + # ------------------------------------------ + # none none none inconceivable! + # exists none none use V1 + # none exists none use Vuser + # none none exists use V2 + # exists none exists use V2 + # exists exists none use V2 + # none exists exists diff V2 Vuser applied to V2 + # exists exists exists diff V1 Vuser applied to V2 + + v1_exists=$(test -f "$v1" && echo exists || echo none) + vu_exists=$(test -f "$vu" && echo exists || echo none) + v2_exists=$(test -f "$v2" && echo exists || echo none) + case "$v1_exists $vu_exists $v2_exists" in + 'exists none none') + cp -a "$v1" "$vt" + ;; + 'none exists none') + cp -a "$vu" "$vt" + ;; + 'none none exists') + cp -a "$v2" "$vt" + ;; + 'exists none exists') + cp -a "$v2" "$vt" + ;; + 'exists exists none') + # In the relevant mustard node it is specified that + # when we have v1 and vu, but not v2, we shouldn't + # do nothing. I changed to copy the user configuration + # instead + cp -a "$vu" "$vt" + ;; + 'none exists exists') + # In the relevant mustard node it is specified a diff + # between /dev/null and vu. However this causes a + # complaint against reversed patches. The option + # "-R" didn't help. + if ! (diff "$v2" "$vu" | patch "$v2" -o "$vt"); then + cp -a "$v2" "$vt" # merge failed, use v2 + fi + ;; + 'exists exists exists') + if ! (diff "$v1" "$vu" | patch "$v2" -o "$vt"); then + cp -a "$v2" "$vt" # merge failed, use v2 + fi + ;; + *) + die "ERROR: unexpected error" + ;; + esac +} + + +if [ "$#" = 0 ]; then + usage "$0" +fi + + +if [ "$1" = "test" ]; then + if [ "$#" != 5 ]; then + usage "$0" + fi + local v1="$2" + local vu="$3" + local v2="$4" + local vt="$5" + mkdir -p "$vt" + # For every pathname in V1, Vuser, or V2 + merge "$v1" "$v1" "$vu" "$v2" "$vt" + merge "$vu" "$v1" "$vu" "$v2" "$vt" + merge "$v2" "$v1" "$vu" "$v2" "$vt" +elif [ "$1" = "merge" ]; then + if [ "$#" != 2 ]; then + usage "$0" + fi + local new_version="$2" + local mounting_point=$(mktemp -d) + "$mounting_script" "$mounting_point" + trap 'umount "$mounting_point"' INT ERR EXIT + if [ ! -d "$mounting_point/systems/$new_version" ]; then + die "Error: version not found - '$new_version'" + fi + local v1_dir="$mounting_point/systems/default/orig/etc" + local vu_dir="$mounting_point/systems/default/run/etc" + local v2_dir="$mounting_point/systems/$new_version/run/etc" + local vt_dir="$mounting_point/systems/$new_version/run/etc.new" + mkdir "$vt_dir" + + # For every pathname in V1, Vuser, or V2 + merge "$v1_dir" "$v1_dir" "$vu_dir" "$v2_dir" "$vt_dir" + merge "$vu_dir" "$v1_dir" "$vu_dir" "$v2_dir" "$vt_dir" + merge "$v2_dir" "$v1_dir" "$vu_dir" "$v2_dir" "$vt_dir" + + rm -rf "$v2_dir" + mv "$vt_dir" "$v2_dir" +elif [ "$1" = "sync" ]; then + local canonical_version="$2" + local mounting_point=$(mktemp -d) + "$mounting_script" "$mounting_point" + trap 'umount "$mounting_point"' INT EXIT + if [ ! -d "$mounting_point/systems/$canonical_version" ]; then + die "Error: version not found - '$canonical_version'" + fi + for version_dir in "$mounting_point/systems/"*; do + version="$(basename "$version_dir")" + if [ -d "$version_dir" ] && [ ! -h "$version_dir" ] \ + && [ $version != $canonical_version ]; then + cp -a "$mounting_point/systems/$canonical_version/run/etc" \ + "$version_dir/run/etc.new" + mv "$version_dir/run/etc" "$version_dir/run/etc.old" + mv "$version_dir/run/etc.new" "$version_dir/run/etc" + rm -rf "$version_dir/run/etc.old" + fi + done +else + usage "$0" +fi + |