1 files changed, 111 insertions, 0 deletions
diff --git a/forwarddown.in b/forwarddown.in
new file mode 100644
index 0000000..31b4487
--- /dev/null
+++ b/forwarddown.in
@@ -0,0 +1,111 @@
+#!/bin/bash
+
+[ -r "#ETCDIR#/backup.conf" ] && \
+  . "#ETCDIR#/backup.conf"
+
+usage()
+{
+  >&2 echo \
+'Usage:  forwarddown key-id date backup-id1 backup-id2 ...
+Write encrypted, compressed tar from backed up files not newer than date to stdout.
+
+Options:
+  key-id        key id of key to encrypt to
+  date          backup should not be newer than the given date
+  backup-id[n]  backups to restore
+#HELPTEXT#              #'
+  [ -z "$1" ] && exit 1
+  exit $1
+}
+
+if [ $# -eq 1 ]; then
+  if [ "$1" == "--help" ]; then
+    usage 0
+  elif [ "$1" == "--version" ]; then
+    echo '#VERSION#'
+    exit
+  fi
+fi
+
+if [ $# -lt 3 ]; then
+  usage
+fi
+
+key_id=$(
+  printf '%s\n' "$1" \
+  | tr '[:lower:]' '[:upper:]'
+)
+shift
+
+if ! gpg --list-keys --with-colon "${key_id}" \
+| grep -qxF 'fpr:::::::::'"${key_id}"':'; then
+  >&2 printf 'Cannot find gpg key with fingerprint "%s"\n' "${key_id}"
+  usage
+fi
+
+if ! date=$(date -u '+%Y_%m_%d' -d"${1}"); then
+  >&2 printf 'Cannot parse date "%s"\n' "${1}"
+  usage
+fi
+shift
+
+forwarddown_dirs=()
+
+for backup_id in "$@"; do
+  if [ -z "${backups[${backup_id}]}" ]; then
+    >&2 printf 'backup id "%s" is unknown\n' "${backup_id}"
+    usage
+  fi
+  forwarddown_dirs+=("${backups[${backup_id}]## *}")
+done
+
+date=$(
+  {
+    find "${forwarddown_dirs[@]%% *}" -mindepth 1 -maxdepth 1 -type d -printf '0 %f\n'
+    printf '1 %s\n' "${date}"
+  } \
+  | sort -k2,2 -k1,1 \
+  | sed '
+    s/^0 //
+    t
+    /^1 / q
+  ' \
+  | uniq -c \
+  | sed '
+    s/^\s*'"${#forwarddown_dirs[@]}"'\s\+//
+    t
+    d
+  ' \
+  | tail -n1
+)
+
+transforms=(
+  $(
+    for backup_id in "$@"; do
+      printf -- '--transform=s@^%s/%s/@%s/%s/@\n' \
+        "${backups[${backup_id}]%% *}" \
+        "${date}" \
+        "${date}" \
+        "${backup_id}"
+    done
+  )
+)
+
+directories=(
+  $(
+    for backup_id in "$@"; do
+      printf '%s/%s/\n' \
+        "${backups[${backup_id}]%% *}" \
+        "${date}"
+    done
+  )
+)
+
+tar \
+  -c \
+  -f - \
+  --absolute-names \
+  "${transforms[@]}" \
+  "${directories[@]}" \
+| pigz --best -c - \
+| gpg -e -r "${key_id}" -o - -