Merge remote-tracking branch 'upstream/master'

Conflicts:
	rsync_tmbackup.sh

3 files changed, 288 insertions, 185 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e8d64cc
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+.idea
+test.sh
\ No newline at end of file
diff --git a/README.md b/README.md
index 973cec4..27bd812 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,10 @@
 # Rsync time backup
 
-Time Machine style backup with rsync. Should work on Linux (tested), Mac OS X (tested) and Windows with Cygwin (not tested yet but feedback would be welcome).
+This script offers Time Machine-style backup using rsync. It creates incremental backups of files and directories to the destination of your choice. The backups are structured in a way that makes it easy to recover any file at any point in time.
+
+It should work on Linux, OS X and Windows with Cygwin. The main advantage over Time Machine is the flexibility as it can backup from/to any filesystem and works on any platform. You can also backup, for example, to a Truecrypt drive without any problem.
+
+On OS X, it has a few disadvantages compared to Time Machine - in particular it doesn't auto-start when the backup drive is plugged (though it can be achieved using a launch agent), it requires some knowledge of the command line, and no specific GUI is provided to restore files. Instead files can be restored by using any file explorer, including Finder, or the command line.
 
 # Installation
 
@@ -28,6 +32,8 @@ An optional exclude file can be provided as a third parameter. It should be comp
 
 * Each backup is on its own folder named after the current timestamp. Files can be copied and restored directly, without any intermediate tool.
 
+* Backup to remote destinations over SSH.
+
 * Files that haven't changed from one backup to the next are hard-linked to the previous backup so take very little extra space.
 
 * Safety check - the backup will only happen if the destination has explicitly been marked as a backup destination.
@@ -40,18 +46,32 @@ An optional exclude file can be provided as a third parameter. It should be comp
 
 * "latest" symlink that points to the latest successful backup.
 
-* The application is just one bash script that can be easily edited.
-
 # TODO
 
 * Check source and destination file-system. If one of them is FAT, use the --modify-window rsync parameter (see `man rsync`) with a value of 1 or 2.
 
 * Minor changes (see TODO comments in the source).
 
-* Backup to remote drive?
-
 # LICENSE
 
-[MIT](http://opensource.org/licenses/MIT)
+The MIT License (MIT)
+
+Copyright (c) 2013-2016 Laurent Cozic
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
 
-[![Bitdeli Badge](https://d2weczhvl823v0.cloudfront.net/laurent22/rsync-time-backup/trend.png)](https://bitdeli.com/free "Bitdeli Badge")
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/rsync_tmbackup.sh b/rsync_tmbackup.sh
index 11ccdd7..a5dd28d 100755
--- a/rsync_tmbackup.sh
+++ b/rsync_tmbackup.sh
@@ -9,14 +9,21 @@ APPNAME=$(basename $0 | sed "s/\.sh$//")
 fn_log_info()  { echo "$APPNAME: $1"; }
 fn_log_warn()  { echo "$APPNAME: [WARNING] $1" 1>&2; }
 fn_log_error() { echo "$APPNAME: [ERROR] $1" 1>&2; }
+fn_log_info_cmd()  {
+    if [ -n "$SSH_CMD" ]; then
+        echo "$APPNAME: $SSH_CMD '$1'";
+    else
+        echo "$APPNAME: $1";
+    fi
+}
 
 # -----------------------------------------------------------------------------
 # Make sure everything really stops when CTRL+C is pressed
 # -----------------------------------------------------------------------------
 
 fn_terminate_script() {
-	fn_log_info "SIGINT caught."
-	exit 1
+    fn_log_info "SIGINT caught."
+    exit 1
 }
 
 trap 'fn_terminate_script' SIGINT
@@ -25,58 +32,113 @@ trap 'fn_terminate_script' SIGINT
 # Small utility functions for reducing code duplication
 # -----------------------------------------------------------------------------
 fn_display_usage() {
-	fn_log_info "Usage : $(basename $0) <source> [destination] [exclude-pattern file]"
+	fn_log_info "Usage : $(basename $0) <source> [[[user@host:]destination] exclude-pattern-file]"
 }
 
 fn_parse_date() {
-	# Converts YYYY-MM-DD-HHMMSS to YYYY-MM-DD HH:MM:SS and then to Unix Epoch.
-	case "$OSTYPE" in
-		linux*) date -d "${1:0:10} ${1:11:2}:${1:13:2}:${1:15:2}" +%s ;;
-		cygwin*) date -d "${1:0:10} ${1:11:2}:${1:13:2}:${1:15:2}" +%s ;;
-		darwin*) date -j -f "%Y-%m-%d-%H%M%S" "$1" "+%s" ;;
-	esac
+    # Converts YYYY-MM-DD-HHMMSS to YYYY-MM-DD HH:MM:SS and then to Unix Epoch.
+    case "$OSTYPE" in
+        linux*) date -d "${1:0:10} ${1:11:2}:${1:13:2}:${1:15:2}" +%s ;;
+        cygwin*) date -d "${1:0:10} ${1:11:2}:${1:13:2}:${1:15:2}" +%s ;;
+        darwin*) date -j -f "%Y-%m-%d-%H%M%S" "$1" "+%s" ;;
+    esac
 }
 
 fn_find_backups() {
-	find "$DEST_FOLDER" -type d -name "????-??-??-??????" -prune | sort -r
+    fn_run_cmd "find "$DEST_FOLDER" -type d -name "????-??-??-??????" -prune | sort -r"
 }
 
 fn_expire_backup() {
-	# Double-check that we're on a backup destination to be completely
-	# sure we're deleting the right folder
-	if [ -z "$(fn_find_backup_marker "$(dirname -- "$1")")" ]; then
-		fn_log_error "$1 is not on a backup destination - aborting."
-		exit 1
-	fi
+    # Double-check that we're on a backup destination to be completely
+    # sure we're deleting the right folder
+    if [ -z "$(fn_find_backup_marker "$(dirname -- "$1")")" ]; then
+        fn_log_error "$1 is not on a backup destination - aborting."
+        exit 1
+    fi
+
+    fn_log_info "Expiring $1"
+    fn_rm "$1"
+}
 
-	fn_log_info "Expiring $1"
-	rm -rf -- "$1"
+fn_parse_ssh() {
+    if [[ "$DEST_FOLDER" =~ ^[A-Za-z0-9\._%\+\-]+@[A-Za-z0-9.\-]+\:.+$ ]]
+    then
+        SSH_USER=$(echo "$DEST_FOLDER" | sed -E  's/^([A-Za-z0-9\._%\+\-]+)@([A-Za-z0-9.\-]+)\:(.+)$/\1/')
+        SSH_HOST=$(echo "$DEST_FOLDER" | sed -E  's/^([A-Za-z0-9\._%\+\-]+)@([A-Za-z0-9.\-]+)\:(.+)$/\2/')
+        SSH_DEST_FOLDER=$(echo "$DEST_FOLDER" | sed -E  's/^([A-Za-z0-9\._%\+\-]+)@([A-Za-z0-9.\-]+)\:(.+)$/\3/')
+        SSH_CMD="ssh ${SSH_USER}@${SSH_HOST}"
+        SSH_FOLDER_PREFIX="${SSH_USER}@${SSH_HOST}:"
+    fi
+}
+
+fn_run_cmd() {
+    if [ -n "$SSH_CMD" ]
+    then
+        eval "$SSH_CMD '$1'"
+    else
+        eval $1
+    fi
+}
+
+fn_find() {
+    fn_run_cmd "find $1"  2>/dev/null
+}
+
+fn_get_absolute_path() {
+    fn_run_cmd "cd $1;pwd"
+}
+
+fn_mkdir() {
+    fn_run_cmd "mkdir -p -- $1"
+}
+
+fn_rm() {
+    fn_run_cmd "rm -rf -- $1"
+}
+
+fn_touch() {
+    fn_run_cmd "touch -- $1"
+}
+
+fn_ln() {
+    fn_run_cmd "ln -vs -- $1 $2"
 }
 
 # -----------------------------------------------------------------------------
 # Source and destination information
 # -----------------------------------------------------------------------------
+SSH_USER=""
+SSH_HOST=""
+SSH_DEST_FOLDER=""
+SSH_CMD=""
+SSH_FOLDER_PREFIX=""
+
 #display usage information if required arguments are not passed
 if [[ "${#@}" -lt 1 ]]; then
 	fn_display_usage
 	exit 1
 fi
-
 SRC_FOLDER="${1%/}"
+
 #if destination folder is not specified assume current folder
 if [ -z ${2} ]; then
 	DEST_FOLDER="."
-	echo ${2}
 else
 	DEST_FOLDER="${2%/}"
 fi
 EXCLUSION_FILE="$3"
 
+fn_parse_ssh
+
+if [ -n "$SSH_DEST_FOLDER" ]; then
+    DEST_FOLDER="$SSH_DEST_FOLDER"
+fi
+
 for ARG in "$SRC_FOLDER" "$DEST_FOLDER" "$EXCLUSION_FILE"; do
 if [[ "$ARG" == *"'"* ]]; then
-		fn_log_error 'Arguments may not have any single quote characters.'
-		exit 1
-	fi
+        fn_log_error 'Arguments may not have any single quote characters.'
+        exit 1
+    fi
 done
 
 # -----------------------------------------------------------------------------
@@ -86,15 +148,15 @@ done
 # TODO: check that the destination supports hard links
 
 fn_backup_marker_path() { echo "$1/backup.marker"; }
-fn_find_backup_marker() { find "$(fn_backup_marker_path "$1")" 2>/dev/null; }
+fn_find_backup_marker() { fn_find "$(fn_backup_marker_path "$1")" 2>/dev/null; }
 
 if [ -z "$(fn_find_backup_marker "$DEST_FOLDER")" ]; then
-	fn_log_info "Safety check failed - the destination does not appear to be a backup folder or drive (marker file not found)."
-	fn_log_info "If it is indeed a backup folder, you may add the marker file by running the following command:"
-	fn_log_info ""
-	fn_log_info "touch \"$(fn_backup_marker_path "$DEST_FOLDER")\""
-	fn_log_info ""
-	exit 1
+    fn_log_info "Safety check failed - the destination does not appear to be a backup folder or drive (marker file not found)."
+    fn_log_info "If it is indeed a backup folder, you may add the marker file by running the following command:"
+    fn_log_info ""
+    fn_log_info_cmd "mkdir -p -- \"$DEST_FOLDER\" ; touch \"$(fn_backup_marker_path "$DEST_FOLDER")\""
+    fn_log_info ""
+    exit 1
 fi
 
 # -----------------------------------------------------------------------------
@@ -104,176 +166,195 @@ fi
 # Date logic
 NOW=$(date +"%Y-%m-%d-%H%M%S")
 EPOCH=$(date "+%s")
-KEEP_ALL_DATE=$(($EPOCH - 86400))       # 1 day ago
-KEEP_DAILIES_DATE=$(($EPOCH - 2678400)) # 31 days ago
+KEEP_ALL_DATE=$((EPOCH - 86400))       # 1 day ago
+KEEP_DAILIES_DATE=$((EPOCH - 2678400)) # 31 days ago
 
 export IFS=$'\n' # Better for handling spaces in filenames.
 PROFILE_FOLDER="$HOME/.$APPNAME"
 DEST="$DEST_FOLDER/$NOW"
 PREVIOUS_DEST="$(fn_find_backups | head -n 1)"
 INPROGRESS_FILE="$DEST_FOLDER/backup.inprogress"
+MYPID="$$"
 
 # -----------------------------------------------------------------------------
 # Create profile folder if it doesn't exist
 # -----------------------------------------------------------------------------
 
 if [ ! -d "$PROFILE_FOLDER" ]; then
-	fn_log_info "Creating profile folder in '$PROFILE_FOLDER'..."
-	mkdir -- "$PROFILE_FOLDER"
+    fn_log_info "Creating profile folder in '$PROFILE_FOLDER'..."
+    mkdir -- "$PROFILE_FOLDER"
 fi
 
 # -----------------------------------------------------------------------------
 # Handle case where a previous backup failed or was interrupted.
 # -----------------------------------------------------------------------------
 
-if [ -f "$INPROGRESS_FILE" ]; then
-	if [ -n "$PREVIOUS_DEST" ]; then
-		# - Last backup is moved to current backup folder so that it can be resumed.
-		# - 2nd to last backup becomes last backup.
-		fn_log_info "$INPROGRESS_FILE already exists - the previous backup failed or was interrupted. Backup will resume from there."
-		mv -- "$PREVIOUS_DEST" "$DEST"
-		if [ "$(fn_find_backups | wc -l)" -gt 1 ]; then
-			PREVIOUS_DEST="$(fn_find_backups | sed -n '2p')"
-		else
-			PREVIOUS_DEST=""
-		fi
+if [ -n "$(fn_find "$INPROGRESS_FILE")" ]; then
+	if [ "$OSTYPE" == "cygwin" ]; then
+		# TODO: Cygwin reports the name of currently running Bash scripts as just "/usr/bin/bash"
+		# TODO: so the pgrep solution below won't work. Need to use "procps -wwFAH", grep
+		# TODO: the script name, and extract the process ID from it.
+		fn_log_warn "Cygwin only: Previous backup task has either been interrupted or it might still be active, but there is currently no check for this. Assuming that the task was simply interrupted."
+	else 
+	    RUNNINGPID="$(fn_run_cmd "cat $INPROGRESS_FILE")"
+	    if [ "$RUNNINGPID"="$(pgrep "$APPNAME")" ]; then
+	        fn_log_error "Previous backup task is still active - aborting."
+	        exit 1
+	    fi
 	fi
+
+    if [ -n "$PREVIOUS_DEST" ]; then
+        # - Last backup is moved to current backup folder so that it can be resumed.
+        # - 2nd to last backup becomes last backup.
+        fn_log_info "$SSH_FOLDER_PREFIX$INPROGRESS_FILE already exists - the previous backup failed or was interrupted. Backup will resume from there."
+        fn_run_cmd "mv -- $PREVIOUS_DEST $DEST"
+        if [ "$(fn_find_backups | wc -l)" -gt 1 ]; then
+            PREVIOUS_DEST="$(fn_find_backups | sed -n '2p')"
+        else
+            PREVIOUS_DEST=""
+        fi
+        # update PID to current process to avoid multiple concurrent resumes
+        fn_run_cmd "echo $MYPID > $INPROGRESS_FILE"
+    fi
 fi
 
 # Run in a loop to handle the "No space left on device" logic.
 while : ; do
 
-	# -----------------------------------------------------------------------------
-	# Check if we are doing an incremental backup (if previous backup exists).
-	# -----------------------------------------------------------------------------
-
-	LINK_DEST_OPTION=""
-	if [ -z "$PREVIOUS_DEST" ]; then
-		fn_log_info "No previous backup - creating new one."
-	else
-		# If the path is relative, it needs to be relative to the destination. To keep
-		# it simple, just use an absolute path. See http://serverfault.com/a/210058/118679
-		PREVIOUS_DEST="$(cd "$PREVIOUS_DEST"; pwd)"
-		fn_log_info "Previous backup found - doing incremental backup from $PREVIOUS_DEST"
-		LINK_DEST_OPTION="--link-dest='$PREVIOUS_DEST'"
-	fi
-
-	# -----------------------------------------------------------------------------
-	# Create destination folder if it doesn't already exists
-	# -----------------------------------------------------------------------------
-
-	if [ ! -d "$DEST" ]; then
-		fn_log_info "Creating destination $DEST"
-		mkdir -p -- "$DEST"
-	fi
-
-	# -----------------------------------------------------------------------------
-	# Purge certain old backups before beginning new backup.
-	# -----------------------------------------------------------------------------
-
-	# Default value for $PREV ensures that the most recent backup is never deleted.
-	PREV="0000-00-00-000000"
-	for FILENAME in $(fn_find_backups | sort -r); do
-		BACKUP_DATE=$(basename "$FILENAME")
-		TIMESTAMP=$(fn_parse_date $BACKUP_DATE)
-
-		# Skip if failed to parse date...
-		if [ -z "$TIMESTAMP" ]; then
-			fn_log_warn "Could not parse date: $FILENAME"
-			continue
-		fi
-
-		if   [ $TIMESTAMP -ge $KEEP_ALL_DATE ]; then
-			true
-		elif [ $TIMESTAMP -ge $KEEP_DAILIES_DATE ]; then
-			# Delete all but the most recent of each day.
-			[ "${BACKUP_DATE:0:10}" == "${PREV:0:10}" ] && fn_expire_backup "$FILENAME"
-		else
-			# Delete all but the most recent of each month.
-			[ "${BACKUP_DATE:0:7}" == "${PREV:0:7}" ] && fn_expire_backup "$FILENAME"
-		fi
-
-		PREV=$BACKUP_DATE
-	done
-
-	# -----------------------------------------------------------------------------
-	# Start backup
-	# -----------------------------------------------------------------------------
-
-	LOG_FILE="$PROFILE_FOLDER/$(date +"%Y-%m-%d-%H%M%S").log"
-
-	fn_log_info "Starting backup..."
-	fn_log_info "From: $SRC_FOLDER"
-	fn_log_info "To:   $DEST"
-
-	CMD="rsync"
-	CMD="$CMD --compress"
-	CMD="$CMD --numeric-ids"
-	CMD="$CMD --links"
-	CMD="$CMD --hard-links"
-	CMD="$CMD --one-file-system"
-	CMD="$CMD --archive"
-	CMD="$CMD --itemize-changes"
-	CMD="$CMD --verbose"
-	CMD="$CMD --log-file '$LOG_FILE'"
-	if [ -n "$EXCLUSION_FILE" ]; then
-		# We've already checked that $EXCLUSION_FILE doesn't contain a single quote
-		CMD="$CMD --exclude-from '$EXCLUSION_FILE'"
-	fi
-	CMD="$CMD $LINK_DEST_OPTION"
-	CMD="$CMD -- '$SRC_FOLDER/' '$DEST/'"
-	CMD="$CMD | grep -E '^deleting|[^/]$'"
-
-	fn_log_info "Running command:"
-	fn_log_info "$CMD"
-
-	touch -- "$INPROGRESS_FILE"
-	eval $CMD
-
-	# -----------------------------------------------------------------------------
-	# Check if we ran out of space
-	# -----------------------------------------------------------------------------
-
-	# TODO: find better way to check for out of space condition without parsing log.
-	NO_SPACE_LEFT="$(grep "No space left on device (28)\|Result too large (34)" "$LOG_FILE")"
-
-	if [ -n "$NO_SPACE_LEFT" ]; then
-		fn_log_warn "No space left on device - removing oldest backup and resuming."
-
-		if [[ "$(fn_find_backups | wc -l)" -lt "2" ]]; then
-			fn_log_error "No space left on device, and no old backup to delete."
-			exit 1
-		fi
-
-		fn_expire_backup "$(fn_find_backups | tail -n 1)"
-
-		# Resume backup
-		continue
-	fi
-
-	# -----------------------------------------------------------------------------
-	# Check whether rsync reported any errors
-	# -----------------------------------------------------------------------------
-	
-	if [ -n "$(grep "rsync:" "$LOG_FILE")" ]; then
-		fn_log_warn "Rsync reported a warning, please check '$LOG_FILE' for more details."
-	fi
-	if [ -n "$(grep "rsync error:" "$LOG_FILE")" ]; then
-		fn_log_error "Rsync reported an error, please check '$LOG_FILE' for more details."
-		exit 1
-	fi
-
-	# -----------------------------------------------------------------------------
-	# Add symlink to last successful backup
-	# -----------------------------------------------------------------------------
-
-	rm -rf -- "$DEST_FOLDER/latest"
-	ln -vs -- "$(basename -- "$DEST")" "$DEST_FOLDER/latest"
-
-	rm -f -- "$INPROGRESS_FILE"
-	rm -f -- "$LOG_FILE"
-	
-	fn_log_info "Backup completed without errors."
-
-	exit 0
+    # -----------------------------------------------------------------------------
+    # Check if we are doing an incremental backup (if previous backup exists).
+    # -----------------------------------------------------------------------------
+
+    LINK_DEST_OPTION=""
+    if [ -z "$PREVIOUS_DEST" ]; then
+        fn_log_info "No previous backup - creating new one."
+    else
+        # If the path is relative, it needs to be relative to the destination. To keep
+        # it simple, just use an absolute path. See http://serverfault.com/a/210058/118679
+        PREVIOUS_DEST="$(fn_get_absolute_path "$PREVIOUS_DEST")"
+        fn_log_info "Previous backup found - doing incremental backup from $SSH_FOLDER_PREFIX$PREVIOUS_DEST"
+        LINK_DEST_OPTION="--link-dest='$PREVIOUS_DEST'"
+    fi
+
+    # -----------------------------------------------------------------------------
+    # Create destination folder if it doesn't already exists
+    # -----------------------------------------------------------------------------
+
+    if [ -z "$(fn_find "$DEST -type d" 2>/dev/null)" ]; then
+        fn_log_info "Creating destination $SSH_FOLDER_PREFIX$DEST"
+        fn_mkdir "$DEST"
+    fi
+
+    # -----------------------------------------------------------------------------
+    # Purge certain old backups before beginning new backup.
+    # -----------------------------------------------------------------------------
+
+    # Default value for $PREV ensures that the most recent backup is never deleted.
+    PREV="0000-00-00-000000"
+    for FILENAME in $(fn_find_backups | sort -r); do
+        BACKUP_DATE=$(basename "$FILENAME")
+        TIMESTAMP=$(fn_parse_date $BACKUP_DATE)
+
+        # Skip if failed to parse date...
+        if [ -z "$TIMESTAMP" ]; then
+            fn_log_warn "Could not parse date: $FILENAME"
+            continue
+        fi
+
+        if   [ $TIMESTAMP -ge $KEEP_ALL_DATE ]; then
+            true
+        elif [ $TIMESTAMP -ge $KEEP_DAILIES_DATE ]; then
+            # Delete all but the most recent of each day.
+            [ "${BACKUP_DATE:0:10}" == "${PREV:0:10}" ] && fn_expire_backup "$FILENAME"
+        else
+            # Delete all but the most recent of each month.
+            [ "${BACKUP_DATE:0:7}" == "${PREV:0:7}" ] && fn_expire_backup "$FILENAME"
+        fi
+
+        PREV=$BACKUP_DATE
+    done
+
+    # -----------------------------------------------------------------------------
+    # Start backup
+    # -----------------------------------------------------------------------------
+
+    LOG_FILE="$PROFILE_FOLDER/$(date +"%Y-%m-%d-%H%M%S").log"
+
+    fn_log_info "Starting backup..."
+    fn_log_info "From: $SRC_FOLDER"
+    fn_log_info "To:   $SSH_FOLDER_PREFIX$DEST"
+
+    CMD="rsync"
+    if [ -n "$SSH_CMD" ]; then
+        CMD="$CMD  -e 'ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null'"
+    fi
+    CMD="$CMD --compress"
+    CMD="$CMD --numeric-ids"
+    CMD="$CMD --links"
+    CMD="$CMD --hard-links"
+    CMD="$CMD --one-file-system"
+    CMD="$CMD --archive"
+    CMD="$CMD --itemize-changes"
+    CMD="$CMD --verbose"
+    CMD="$CMD --log-file '$LOG_FILE'"
+    if [ -n "$EXCLUSION_FILE" ]; then
+        # We've already checked that $EXCLUSION_FILE doesn't contain a single quote
+        CMD="$CMD --exclude-from '$EXCLUSION_FILE'"
+    fi
+    CMD="$CMD $LINK_DEST_OPTION"
+    CMD="$CMD -- '$SRC_FOLDER/' '$SSH_FOLDER_PREFIX$DEST/'"
+    CMD="$CMD | grep -E '^deleting|[^/]$'"
+
+    fn_log_info "Running command:"
+    fn_log_info "$CMD"
+
+    fn_run_cmd "echo $MYPID > $INPROGRESS_FILE"
+
+    eval $CMD
+
+    # -----------------------------------------------------------------------------
+    # Check if we ran out of space
+    # -----------------------------------------------------------------------------
+
+    # TODO: find better way to check for out of space condition without parsing log.
+    NO_SPACE_LEFT="$(grep "No space left on device (28)\|Result too large (34)" "$LOG_FILE")"
+
+    if [ -n "$NO_SPACE_LEFT" ]; then
+        fn_log_warn "No space left on device - removing oldest backup and resuming."
+
+        if [[ "$(fn_find_backups | wc -l)" -lt "2" ]]; then
+            fn_log_error "No space left on device, and no old backup to delete."
+            exit 1
+        fi
+
+        fn_expire_backup "$(fn_find_backups | tail -n 1)"
+
+        # Resume backup
+        continue
+    fi
+
+    # -----------------------------------------------------------------------------
+    # Check whether rsync reported any errors
+    # -----------------------------------------------------------------------------
+    if [ -n "$(grep "rsync:" "$LOG_FILE")" ]; then
+        fn_log_warn "Rsync reported a warning, please check '$LOG_FILE' for more details."
+    fi
+    if [ -n "$(grep "rsync error:" "$LOG_FILE")" ]; then
+        fn_log_error "Rsync reported an error, please check '$LOG_FILE' for more details."
+        exit 1
+    fi
+
+    # -----------------------------------------------------------------------------
+    # Add symlink to last successful backup
+    # -----------------------------------------------------------------------------
+
+    fn_rm "$DEST_FOLDER/latest"
+    fn_ln "$(basename -- "$DEST")" "$DEST_FOLDER/latest"
+
+    fn_rm "$INPROGRESS_FILE"
+    rm -f -- "$LOG_FILE"
+
+    fn_log_info "Backup completed without errors."
+
+    exit 0
 done