add dry-run, backup-only and prune-only optionsHEADmaster

2 files changed, 36 insertions, 19 deletions

diff --git a/backomp b/backomp
index f955916..1d465fa 100755
--- a/backomp
+++ b/backomp
@@ -42,7 +42,7 @@ BEGIN {
 	wshift = (11 - arr2[opt_week_start])*24*60*60
 }
 
-!n_buckets || NR == 1 {
+!n_buckets || keep_first && NR == 1 {
 	++keep[$0]
 }
 
@@ -113,7 +113,7 @@ parse_flags() {
 }
 
 qargs() {
-	local arg str=
+	local arg str
 
 	for arg; do
 		[[ "${arg:-*}" =~ [^A-Za-z0-9%+./:=@_-] ]] && arg="${arg@Q}"
@@ -198,7 +198,7 @@ filter() {
 	local -n __src="${1}" __dest="${2}"
 	local __label="${3}" __script="${4}"
 	shift 4
-	local res
+	local res c="${#__src[@]}"
 
 	mapfile -td '' __dest < <(
 		printf '%s\0' "${__src[@]}" | \
@@ -210,7 +210,7 @@ filter() {
 		return 1
 	fi
 
-	if ((${#__src[@]})); then
+	if ((!DRY && c)); then
 		exists "${__dest[0]}" && return 0
 		[[ "$?" -eq 1 ]] &&
 			err "${__label} returned empty or invalid list"
@@ -238,10 +238,12 @@ populate() {
 	fi
 
 	if [[ "${__dir}" =~ ^([^:/]*):(.*) ]]; then
-		mapfile -td '' __arr < <(
-			ssh_run "${BASH_REMATCH[1]}" \
-				"shopt -s nullglob; printf '%s\0' $( \
-					printf '%q' "${BASH_REMATCH[2]}")/*")
+		read -rd '' cmd <<-EOF
+			shopt -s nullglob
+			x=($(printf '%q' "${BASH_REMATCH[2]}")/*)
+			((!\${#x[@]})) || printf '%s\0' \"\${x[@]}\"
+		EOF
+		mapfile -td '' __arr < <(ssh_run "${BASH_REMATCH[1]}" "${cmd}")
 		wait "$!" || return 1
 
 		__arr=("${__arr[@]/#/${BASH_REMATCH[1]}:}")
@@ -249,7 +251,9 @@ populate() {
 	fi
 
 	mapfile -td '' __arr < <(
-		shopt -s nullglob; printf '%s\0' "${__dir}/"*)
+		shopt -s nullglob
+		x=("${__dir}/"*)
+		((!${#x[@]})) || printf '%s\0' "${x[@]}")
 }
 
 copy() {
@@ -266,6 +270,11 @@ copy() {
 		fi
 	done
 
+	if ((DRY)); then
+		echo "* DRY: copy ${dest}${link_dest:+ (link: ${link_dest})}"
+		return
+	fi
+
 	if [[ -n "${opts['pre_copy']}" ]]; then
 		bash -c "$(declare -p src dest link_dest opts \
 			); temp_dest=$(printf '%q' "${dest}.tmp" \
@@ -318,7 +327,9 @@ prune() {
 		if [[ "${__snaps[__i]}" == "${__keep[__k]}" ]]; then
 			((++__k))
 		else
-			if [[ "${__snaps[__i]}" == rclone://* ]]; then
+			if ((DRY)); then
+				echo "* DRY: prune ${__snaps[__i]}"
+			elif [[ "${__snaps[__i]}" == rclone://* ]]; then
 				run rclone purge -- "${__snaps[__i]#*//}"
 			elif [[ "${__snaps[__i]}" =~ ^([^:/]*):(.*) ]]; then
 				USE_RUN=1 ssh_run "${BASH_REMATCH[1]}" \
@@ -337,7 +348,7 @@ backup() {
 	local rsync_flags="${6}" rclone_flags="${7}" ssh_flags="${8}"
 	local dest_path snaps keep
 
-	if [[ ! -e "${src_path}" ]]; then
+	if ((!NO_BACKUP)) && [[ ! -e "${src_path}" ]]; then
 		err "source does not exist: ${src_path}"
 		return 1
 	fi
@@ -348,22 +359,28 @@ backup() {
 	populate snaps "${dest_dir}" || return 1
 	filter snaps snaps 'pre-snapshot awk prefilter' "${AWK_PREFILTER}" \
 		|| return 1
-	[[ -n "${snaps}" ]] && current "${snaps[0]##*/}" "${interval}" \
-		&& return
 
-	dest_path="${dest_dir}/$(date -u '+%Y-%m-%d-%H%M%S')"
-	copy "${src_path}" "${dest_path}" "${snaps[0]}" || return 1
+	if ((!NO_BACKUP)) && ( [[ -z "${snaps}" ]] ||
+			! current "${snaps[0]##*/}" "${interval}" ); then
+		dest_path="${dest_dir}/$(date -u '+%Y-%m-%d-%H%M%S')"
+		copy "${src_path}" "${dest_path}" "${snaps[0]}" || return 1
+		snaps+=("${dest_path}")
+	fi
+
+	((NO_PRUNE)) && return
 
 	if [[ ! "${retain}" =~ ^( *([0-9]+|\*)\^?[hdwM])*\ *$ ]]; then
 		err "invalid \$retain setting: ${retain}"
 		return 1
 	fi
 
-	snaps+=("${dest_path}")
-	filter snaps snaps 'post-snapshot awk prefilter' "${AWK_PREFILTER}" \
-		|| return 1
+	if [[ -n "${dest_path}" ]]; then
+		filter snaps snaps 'post-snapshot awk prefilter' \
+			"${AWK_PREFILTER}" || return 1
+	fi
 	filter snaps keep 'awk filter' "${AWK_FILTER}" \
 		-v "opt_retain=${retain}" -v "opt_week_start=${week_start}" \
+		-v "keep_first=$((!NO_BACKUP))" \
 		|| return 1
 	prune snaps keep
 }
diff --git a/pre-copy-rclone-hardlink.sh b/pre-copy-rclone-hardlink.sh
index 01f7b6e..aa763b5 100755
--- a/pre-copy-rclone-hardlink.sh
+++ b/pre-copy-rclone-hardlink.sh
@@ -3,7 +3,7 @@
 # Copyright 2023 David Vazgenovich Shakaryan
 
 qargs() {
-	local arg str=
+	local arg str
 
 	for arg; do
 		[[ "${arg:-*}" =~ [^A-Za-z0-9%+./:=@_-] ]] && arg="${arg@Q}"