X-Git-Url: http://git.treefish.org/~alex/backmeupscotty.git/blobdiff_plain/1aa0158b6b4d4aaca7f413d76aec814a206a212b..85ea4b7f90d54f48e0b3f0b7a71cd05983ed8e50:/backmeupscotty

diff --git a/backmeupscotty b/backmeupscotty
index ed41ae2..3ee85c9 100644
--- a/backmeupscotty
+++ b/backmeupscotty
@@ -18,37 +18,32 @@ function scottyerror {
     echo $(upperme): $@ >&2 
 }
 
-if [ $(pidof -x $(basename $0) | wc -w) -gt 2 ]; then 
-    scottyerror Another instance of $(basename $0) is already running!
-    exit 1
-fi
+function ssh255 {
+    ssh $@
+    sshret=$?
 
-while getopts "qn:" opt; do
-    case $opt in
-	q)
-	    exec > /dev/null
-	    ;;
-	n)
-	    BACKUP_RUNEVERYNTHDAY=$OPTARG
-	    ;;
-    esac
-done
+    if [ $sshret -eq 255 ]; then
+	scottyerror "SSH connection failed!"
+	exit 1
+    else
+	return $sshret
+    fi
+}
 
 function grepbackups {
-    ssh $REMOTE_HOST "ls $REMOTE_DIR" | grep -E '[0-9]+-[0-9]+'
+    ssh255 $REMOTE_HOST "ls $REMOTE_DIR" | grep -E '[0-9]+-[0-9]+'
 }
 
 function isIncomplete {
-    if ( ssh $REMOTE_HOST '[ -d '$REMOTE_DIR/incomplete' ]' ); then
+    if ( ssh255 $REMOTE_HOST '[ -d '$REMOTE_DIR/incomplete' ]' ); then
 	return 0
     else
 	return 1
     fi
 }
 
-function isIncompleteOrNthDay {
-    if isIncomplete || \
-	[ $(( ( $(date +%s) / (60*60*24) ) % $BACKUP_RUNEVERYNTHDAY )) -eq 0 ]; 
+function isNthDay {
+    if [ $(( ( $(date +%s) / (60*60*24) ) % $BACKUP_RUNEVERYNTHDAY )) -eq 0 ]; 
     then
 	return 0
     else
@@ -56,6 +51,20 @@ function isIncompleteOrNthDay {
     fi	
 }
 
+function latestTooOld {
+    for oldbackup in $(grepbackups); do
+	tstamp=$(echo $oldbackup | cut -d'-' -f1)
+	
+	if [ $(( $(date +%s) - $tstamp )) -lt \
+	    $(( ($BACKUP_RUNEVERYNTHDAY*24+12)*60*60 )) ]
+	then
+	    return 1
+	fi
+    done
+
+    return 0
+}
+
 function scottysync {
     timestamp=$(date +%s)
 
@@ -81,9 +90,9 @@ function scottysync {
 	rsync_exclude=$(eval echo --exclude={$SYNC_EXC} | tr -d {})
     fi
 
-    if (ssh $REMOTE_HOST '[ ! -d '$REMOTE_DIR' ]'); then
+    if (ssh255 $REMOTE_HOST '[ ! -d '$REMOTE_DIR' ]'); then
 	scottyinfo Creating destination directory $REMOTE_HOST:$REMOTE_DIR
-	ssh $REMOTE_HOST "mkdir $REMOTE_DIR"
+	ssh255 $REMOTE_HOST "mkdir $REMOTE_DIR"
     fi
 
     if isIncomplete; then
@@ -99,7 +108,7 @@ function scottysync {
     
     if [ $? -eq 0 ]; then
 	scottyinfo Timestamping completed backup and linking to current backup
-	ssh $REMOTE_HOST \
+	ssh255 $REMOTE_HOST \
 	    "mv $dir_incomplete $dir_timestamped && rm -f $dir_current && ln -s $(basename $dir_timestamped) $dir_current"
     fi
 
@@ -109,58 +118,104 @@ function scottysync {
 
 	if [ $oldestbackuptstamp -lt $(( $(date +%s) - $ARCHIVE_KEEPNDAYS*60*60*24 )) ]; then
 	    scottyinfo Removing old backup $oldestbackup
-	    ssh $REMOTE_HOST rm -r "$REMOTE_DIR/$oldestbackup"
+	    ssh255 $REMOTE_HOST rm -r "$REMOTE_DIR/$oldestbackup"
 	else
 	    break
 	fi
     done
 }
 
-function prepare {
-    scottyinfo "Preparing for sync"
+function deleteLock {
+    if ! rmdir /tmp/$(basename $0).lock; then
+	scottyerror "Could not delete lockfile /tmp/$(basename $0).lock!"
+    fi
 }
 
-function cleanup_abrt {
-    scottyinfo "No cleanup_abrt function was defined."
+function prepare {
+    scottyinfo "Preparing for sync"
 }
 
-function _cleanup_abrt {
+function cleanup_abort {
     scottyerror "Caught exit signal! Cleaning up..."
-    cleanup_abrt
+
+    cleanup ABORT
+
     if [ $(jobs -p) ]; then
 	scottyerror TERMinating remaining child processes...
 	kill $(jobs -p)
     fi
+
+    deleteLock
+
     exit
 }
 
-function prepare {
-    scottyinfo "No prepare function was defined."
+function cleanup {
+    scottyinfo "No cleanup function was defined."
 }
 
-function _prepare {
-    prepare
+function prepare {
+    scottyinfo "No prepare function was defined."
 }
 
 function cleanup_normal {
-    scottyinfo "No cleanup_normal function was defined."
+    cleanup
+    deleteLock
 }
 
-function _cleanup_normal {
-    cleanup_normal
+function printhelp {
+    cat <<EOF
+Usage: $(basename $0) [OPTION]...
+
+Recognized options:
+  -q   Only output errors
+  -n   Run only on nth day
+  -h   Print out this help
+EOF
 }
 
 function backmeupscotty {
-    if ! isIncompleteOrNthDay; then
-	scottyinfo "This is not the nth day and no incomplete backup exists."
+    while getopts "qn:h" opt; do
+	case $opt in
+	    q)
+		exec > /dev/null
+		;;
+	    n)
+		BACKUP_RUNEVERYNTHDAY=$OPTARG
+		;;
+	    h)
+		printhelp
+                exit 0
+                ;;
+	esac
+    done
+    
+    ssh255 $REMOTE_HOST exit
+
+    if latestTooOld; then
+	scottyerror "The latest backup is too old."
+    elif isNthDay; then
+	scottyinfo "This is the nth day."
+    else
+	scottyinfo "No backup has to be done. Exiting."
 	exit 0
     fi
 
-    trap _cleanup_abrt EXIT
+    scottyinfo "Performing backup."
 
-    _prepare
+    trap cleanup_abort EXIT
+
+    prepare
     scottysync
-    _cleanup_normal
 
-    trap - EXIT
+    trap cleanup_normal EXIT
+
+    exit 0
 }
+
+if ! mkdir /tmp/$(basename $0).lock; then
+    scottyerror "Another instance of $(basename $0) is still running!"
+    exit 1
+else
+    trap deleteLock EXIT
+fi