Abort on low disk space

diff --git a/wizbackup b/wizbackup
index f857379346de4bb5e38bace10e2d9e14c05e9598..816a66b82ff3641eaa40a41f3ebceb4ba97ca33c 100755 (executable)
--- a/wizbackup
+++ b/wizbackup
@@ -20,7 +20,6 @@
 #  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 
-
 if [ $# -lt 2 ]; then
        echo "Usage: $0 SOURCE DEST [RSYNC_OPTS]"
        exit 1
@@ -33,10 +32,10 @@ set -u
 # CONFIGURATION
 #####################################################################
 
-# Source path
+# Source rsync URL
 SRC=$1; shift
 
-# DESTINATION DIRECTORY (must exists)
+# Destination directory (will be created if it doesn't exist)
 DEST=$1; shift
 
 # NOTE: --timeout needs to be large enough: if a large dir tree don't change a lot of time can pass without I/O
@@ -46,6 +45,9 @@ RSYNC_OPTS="-HAXa --stats --timeout 1800 --numeric-ids --delete --delete-exclude
 # Number of saved snapshots
 SNAPSHOTS=45
 
+# Abort backup if the destination volume has less than these GBs free
+MIN_FREE_GB=10
+
 RESULT=500
 DATE=`date +"%Y%m%d"`
 DEST="`echo $DEST | sed -e 's/\/$//'`"
@@ -125,7 +127,7 @@ do_link()
                echo "$(date): Linking snapshot $DEST/$newest to $DEST/tmp"
                # TODO: Creating the hardlinks takes a lot of time.
                # Perhaps we could save time by recycling the oldest snapshot
-               cp -lR "$DEST/$newest" "$DEST/tmp"
+               cp -la "$DEST/$newest" "$DEST/tmp"
                RESULT=$?
                if [ $RESULT -ne 0 ]; then
                        echo "$(date): Failed to setup tmp snapshot: $RESULT. Cleaning up."
@@ -138,6 +140,15 @@ do_link()
 do_test()
 {
        # TODO: test for free space and free inodes in the $DEST filesystem
+       block_size=`stat --file-system --format "%S" "$DEST"`
+       free_blocks=`stat --file-system --format "%f" "$DEST"`
+       free_inodes=`stat --file-system --format "%d" "$DEST"`
+       free_gb=$((block_size * free_blocks / 1024 / 1024 / 1024))
+
+       if [ "$free_gb" -lt "$MIN_FREE_GB" ]; then
+               echo "$(date): Aborting due to insufficient free space ${free_gb}GB."
+               exit 670
+       fi
 
        # Avoid clobbering the latest snapshot if the remote host does
        # not allow us to connect
@@ -150,9 +161,9 @@ do_test()
        fi
 }
 
-######################
-# MAIN
-######################
+######################################
+# Main
+######################################
 
 # make sure to be root
 if (( `id -u` != 0 )); then { echo "Sorry, must be root.  Exiting..."; exit; } fi