Adding upstream version 1.154.1.

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

diff --git a/bin/live-snapshot b/bin/live-snapshot
index b81a6af..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
 
@@ -58,6 +63,7 @@ SNAP_OUTPUT=""
 SNAP_RESYNC_STRING=""
 SNAP_TYPE="cpio"
 SNAP_LIST="/etc/live-snapshot.list"
+EXCLUDE_LIST="/etc/live-snapshot.exclude_list"
 
 Error ()
 {
@@ -315,23 +321,49 @@ 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 right now
+       # BUGS: supports only cpio.gz types, and does not handle deleted files yet
+
        TMP_FILELIST=$1
        if [ -f "${SNAP_LIST}" ]
        then
-               # Generate include list
-               for entry in $(cat "${SNAP_LIST}" | grep -v '^#.*$' | grep -v '^ *$')
+               # Generate include list removing empty and commented lines
+               for entry in $(sed -e '/^ *$/d' -e '/^#.*$/d' "${SNAP_LIST}")
                do
-                       if [ -f "${entry}" ]
-                       then
-                               printf "%s\000" "${entry}" >> "${TMP_FILELIST}"
-                       elif [ -d "${entry}" ]
+                       if [ -d "${entry}" ]
                        then
                                cd /
-                               find "${entry}" -print0 >> "${TMP_FILELIST}"
+                               find "${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
 
@@ -361,6 +393,13 @@ Do_snapshot ()
                        # Removing whiteheads of unionfs
                        cd "${SNAP_COW}"
                        find . -name '*.wh.*' >> "${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 "${TMP_FILELIST}"
                        ;;
@@ -368,10 +407,28 @@ Do_snapshot ()
                cpio)
                        WORKING_DIR=$(Do_filelist "${TMP_FILELIST}")
                        cd "${WORKING_DIR}"
-                       cat "${TMP_FILELIST}" | cpio --quiet -o0 -H newc | gzip -9c > "${DEST}" || exit 1
+                       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...