Actually building/cleaning manpages through targets in Makefile.

[live-boot-grml.git] / bin / live-snapshot

diff --git a/bin/live-snapshot b/bin/live-snapshot
index a6550e5..3d4efad 100755 (executable)
--- a/bin/live-snapshot
+++ b/bin/live-snapshot
@@ -30,7 +30,12 @@
 ROOTSNAP=""
 HOMESNAP=""
 
-set -eu
+if [ -n "${LIVE_SNAPSHOT_CHECK_UNBOUND}" ]
+then
+       set -eu
+else
+       set -e
+fi
 
 . /usr/share/initramfs-tools/scripts/live-helpers
 
@@ -48,13 +53,17 @@ SAFE_TMPDIR="/live"
 # Permits multiple runs
 MOUNTP="$(mktemp -d -p ${SAFE_TMPDIR} live-snapshot-mnt.XXXXXX)"
 DEST="${MOUNTP}/live-sn.cpio.gz"
+DEF_SNAP_COW="/live/cow"
+TMP_FILELIST="${PROGRAM}.list"
 
 # Command line defaults and declarations
-SNAP_COW="/live/cow"
+SNAP_COW="${DEF_SNAP_COW}"
 SNAP_DEV=""
 SNAP_OUTPUT=""
 SNAP_RESYNC_STRING=""
 SNAP_TYPE="cpio"
+SNAP_LIST="/etc/live-snapshot.list"
+EXCLUDE_LIST="/etc/live-snapshot.exclude_list"
 
 Error ()
 {
@@ -312,23 +321,114 @@ Mount_device ()
        esac
 }
 
+Entry_is_modified ()
+{
+       # Returns true if file exists and it is also present in "cow" directory
+       # This means it is modified in respect to read-only media, so it deserve
+       # to be saved
+
+       entry="${1}"
+
+       if [ -e "${entry}" ] || [ -L "${entry}" ]
+       then
+               if [ -e "${DEF_SNAP_COW}/${entry}" ] || [ -L "${DEF_SNAP_COW}/${entry}" ]
+               then
+                       return 0
+               fi
+       fi
+       return 1
+}
+
+Do_filelist ()
+{
+       # BUGS: supports only cpio.gz types, and does not handle deleted files yet
+
+       TMP_FILELIST=$1
+       if [ -f "${SNAP_LIST}" ]
+       then
+               # Generate include list removing empty and commented lines
+               for entry in $(sed -e '/^ *$/d' -e '/^#.*$/d' "${SNAP_LIST}")
+               do
+                       if [ -d "${entry}" ]
+                       then
+                               cd /
+                               find "${entry}" | while read line
+                               do
+                                       if Entry_is_modified "${line}"
+                                       then
+                                               printf "%s\000" "${line}" >> "${TMP_FILELIST}"
+                                       fi
+                               done
+                               cd "${OLDPWD}"
+                       elif Entry_is_modified "${entry}"
+                       then
+                               # if file exists and it is modified
+                               printf "%s\000" "${entry}" >> "${TMP_FILELIST}"
+                       fi
+               done
+
+               if [ "${SNAP_COW}" = "${DEF_SNAP_COW}" ]
+               then
+                       # Relative to rootfs
+                       echo "/"
+               else
+                       # Mostly "/home"
+                       echo "${SNAP_COW}"
+               fi
+       else
+               cd "${SNAP_COW}"
+               find . -path '*.wh.*' -prune -o -print0 >> "${TMP_FILELIST}"
+               cd "${OLDPWD}"
+               echo "${SNAP_COW}"
+       fi
+}
+
 Do_snapshot ()
 {
+       TMP_FILELIST=$(mktemp -p "${SAFE_TMPDIR}" "${TMP_FILELIST}.XXXXXX")
+
        case "${SNAP_TYPE}" in
                squashfs)
-                       EXCLUDE_LIST="$(mktemp -p ${SAFE_TMPDIR} live-snapshot-exclude-list.XXXXXX)"
-                       echo "./${EXCLUDE_LIST}" > "${EXCLUDE_LIST}"
+                       echo ".${TMP_FILELIST}" > "${TMP_FILELIST}"
+                       # Removing whiteheads of unionfs
                        cd "${SNAP_COW}"
-                       find . -name '*.wh.*' >> "${EXCLUDE_LIST}"
+                       find . -name '*.wh.*' >> "${TMP_FILELIST}"
+
+                       if [ -e "${EXCLUDE_LIST}" ]
+                       then
+                               # Add explicitly excluded files
+                               grep -v '^#.*$' "${EXCLUDE_LIST}" | grep -v '^ *$' >> "${TMP_FILELIST}"
+                       fi
+
                        cd "${OLDPWD}"
-                       mksquashfs "${SNAP_COW}" "${DEST}" -ef "${EXCLUDE_LIST}"
-                       rm -f "${EXCLUDE_LIST}"
+                       mksquashfs "${SNAP_COW}" "${DEST}" -ef "${TMP_FILELIST}"
                        ;;
 
                cpio)
-                       ( cd "${SNAP_COW}" && find . -path '*.wh.*' -prune -o -print0 | cpio --quiet -o0 -H newc | gzip -9c > "${DEST}" ) || exit 1
+                       WORKING_DIR=$(Do_filelist "${TMP_FILELIST}")
+                       cd "${WORKING_DIR}"
+                       if [ -e "${EXCLUDE_LIST}" ]
+                       then
+                               # Convert \0 to \n and tag existing (rare but possible) \n in filenames,
+                               # this to let grep -F -v do a proper work in filtering out
+                               cat "${TMP_FILELIST}" | \
+                                       tr '\n' '\1' | \
+                                       tr '\0' '\n' | \
+                                       grep -F -v -f "${EXCLUDE_LIST}" | \
+                                       tr '\n' '\0' | \
+                                       tr '\1' '\n' | \
+                                       cpio --quiet -o0 -H newc | \
+                                       gzip -9c > "${DEST}" || exit 1
+                       else
+                               cat "${TMP_FILELIST}" | \
+                                       cpio --quiet -o0 -H newc | \
+                                       gzip -9c > "${DEST}" || exit 1
+                       fi
+                       cd "${OLDPWD}"
                        ;;
 
+               # ext2|ext3 and jffs2 does not easily support an exclude list; files
+               # should be copied to another directory in order to filter content
                ext2|ext3)
                        DU_DIM="$(du -ks ${SNAP_COW} | cut -f1)"
                        REAL_DIM="$(expr ${DU_DIM} + ${DU_DIM} / 20)" # Just 5% more to be sure, need something more sophistcated here...
@@ -339,6 +439,11 @@ Do_snapshot ()
                        mkfs.jffs2 --root="${SNAP_COW}" --output="${DEST}"
                        ;;
        esac
+
+       if [ -f "${TMP_FILELIST}" ]
+       then
+               rm -f "${TMP_FILELIST}"
+       fi
 }
 
 Clean ()