rename backup -> hardlinked-backup

* avoid file conflict with tar's /usr/bin/backup script

1 files changed, 302 insertions, 0 deletions

diff --git a/hardlinked-backup.in b/hardlinked-backup.in
new file mode 100755
index 0000000..d5c76e2
--- /dev/null
+++ b/hardlinked-backup.in
@@ -0,0 +1,302 @@
+#!/bin/bash
+
+rsyncOptions='-vxcaHAXF'
+rsync --help | \
+  grep -q -- --may-modify-others && \
+  rsyncOptions="${rsyncOptions} --may-modify-others"
+
+[ -r "#ETCDIR#/backup.conf" ] && \
+  . "#ETCDIR#/backup.conf"
+
+usage()
+{
+  >&2 echo \
+'Usage:  hardlinked-backup /tmp/pidFile /path/to/destination/ user@source:path [proxy_user@ssh_host]
+Backup files from remote with rsync, possibly via SSH-tunnel.
+
+With no arguments, information is expected to be in array $backups in #ETCDIR#/backup.conf with name of executable (e.g. a symlink) as key.
+With one argument, information is expected to be in array ${backups[$1]} in #ETCDIR#/backup.conf.
+
+Options:
+  /tmp/pidFile           location of file to store PID in
+  /path/to/destination   location to store backups in
+  user@source:path       remote data to back up
+  proxy_user@ssh_host    ssh login to proxy node (optional)
+#HELPTEXT#              #'
+  [ -z "$1" ] && exit 1
+  exit $1
+}
+
+extract_ssh_host() {
+  {
+    printf '%s\n' "$1"
+    if [ -f ~/.ssh/config ]; then
+      sed '
+        /^Host\s\+'"$1"'$/,/^Host\s/ {
+          s/^\s*Hostname\s\+//
+          t
+        }
+        d
+      ' ~/.ssh/config
+    fi
+  } \
+    | tail -n1
+}
+
+extract_ssh_ip_protocols() {
+  getent ahosts "$(extract_ssh_host "$1")" \
+    | sed '
+      s/^\([0-9]\+\.\)\{3\}[0-9]\+\s\+STREAM\(\s.*\)\?$/4/
+      t
+      s/^[0-9a-f][0-9a-f:]\+\s\+STREAM\(\s.*\)\?$/6/
+      t
+      d
+    ' \
+    | sort -u \
+    | if [ -f ~/.ssh/config ]; then
+      grep -vxF "$(
+        sed '
+          /^Host\s\+'"$1"'$/,/^Host\s/ {
+            s/^\s*AddressFamily\s\+inet\s*$/6/
+            t
+            s/^\s*AddressFamily\s\+inet6\s*$/4/
+            t
+          }
+          d
+        ' ~/.ssh/config
+      )"
+    else
+      cat
+    fi
+}
+
+connected_ip_versions() {
+  ip -o addr show scope global \
+    | awk '{print $4}' \
+    | sed '
+      s@^\([0-9]\+\.\)\{3\}[0-9]\+\(/[0-9]\+\)\?$@4@
+      t
+      s@^[0-9a-f][0-9a-f:]\+\(/[0-9]\+\)\?$@6@
+      t
+      d
+    ' \
+    | sort -u
+}
+
+if [ $# -eq 1 ]; then
+  if [ "$1" == "--help" ]; then
+    usage 0
+  elif [ "$1" == "--version" ]; then
+    echo '#VERSION#'
+    exit
+  fi
+fi
+
+seldom=false
+if [ $# -eq 0 ] || [ $# -eq 1 ]; then
+  if [ $# -eq 0 ]; then
+    backupID="$(basename $0)"
+  else
+    backupID="$1"
+  fi
+  [ -z "${backups[${backupID}]}" ] && usage
+  set /tmp/${backupID}.pid ${backups[${backupID}]}
+  if printf '%s\n' "${seldomBackups[@]}" | \
+    grep -qxF "${backupID}"; then
+    seldom=true
+  fi
+fi
+
+Basis="$2"
+pidFile="$1"
+QuellIP=$(echo "$3" | sed "s|^[a-zA-Z]*://||; s|^[a-zA-Z]*@||; s|:\?/.*$||")
+
+if [ "$#" -eq 3 ]; then
+  Quelle="$3"
+  ipVer=$(
+    {
+      extract_ssh_ip_protocols "${QuellIP}" \
+        | sort -n
+      extract_ssh_ip_protocols "${QuellIP}" \
+        | grep -xF "$(connected_ip_versions)" \
+        | sort -n
+    } \
+      | tail -n1
+  )
+elif [ "$#" -eq 4 ]; then
+  sshHopp="$4"
+  lokPort=$[$RANDOM/2+8000]
+  HoppIP="${sshHopp#*@}"
+  ipVer=$(
+    {
+      extract_ssh_ip_protocols "${QuellIP}"
+      extract_ssh_ip_protocols "${HoppIP}"
+    } \
+      | sort -n \
+      | uniq -d \
+      | tail -n1
+  )
+  if [ -z ${ipVer} ]; then
+    >&2 echo 'not reachable'
+    exit 11
+  fi
+  if [ ${ipVer} -eq 4 ]; then
+    localAddress='127.0.0.1'
+  elif [ ${ipVer} -eq 6 ]; then
+    localAddress='[::1]'
+  else
+    >&2 echo 'ip version of hopp and target must be the same'
+    exit 1
+  fi
+  rsyncShell="-e ssh -${ipVer} -p${lokPort} -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null"
+  tunnelBefehl="ssh -${ipVer} -t -t -L${localAddress}:${lokPort}:${QuellIP}:22 ${sshHopp} while sleep 60; do date; done"
+  Quelle="$(echo "$3" | sed "s|${QuellIP}|${localAddress}|")"
+else
+  usage
+fi
+
+rsyncOptions="${rsyncOptions}${ipVer}"
+
+if [ ! -d ${Basis} ]; then
+  for neededMount in "${neededMounts[@]}"; do
+    if ! mountpoint -q "${neededMount}"; then
+      >&2 printf 'Mountpoint %s is not available.\n' "${neededMount}"
+      exit 11
+    fi
+  done
+  exit 2
+fi
+
+neues_Datum="${Basis}/$(date "+%Y_%m_%d")"
+neues="${Basis}/aktuell"
+linkdests=""
+for s in $(ls -1 "${Basis}" | sort -r | grep -vxF -m 20 aktuell ); do
+  linkdests="${linkdests} --link-dest ${Basis}/${s}"
+done
+
+if [ ! "$(whoami)" == "root" ]; then
+  echo "I need to be root."
+  exit 3
+fi
+
+[ -e "${neues_Datum}" ] && exit 4
+if ${seldom}; then
+  for date_diff in $(seq ${seldomness}); do
+    if [ -e "${Basis}/$(date '+%Y_%m_%d' -d@$(($(date '+%s')-24*60*60*date_diff)))" ]; then
+      exit 4
+    fi
+  done
+fi
+[ -w "${Basis}" ] || exit 11
+[ -s "${pidFile}" ] && [ -d "/proc/$(cat "${pidFile}")" ] && exit 5
+
+echo $$ > "${pidFile}"
+
+if [ -n "${tunnelBefehl}" ]; then
+  preConnectHook
+  ${tunnelBefehl} &
+  backgroundPid=$!
+  sleep 4
+fi
+
+for toExclude in "${excludes[@]}"; do
+  excludeArgs="${excludeArgs} --exclude ${toExclude}"
+done
+
+mkdir -p "${neues}/wip"
+chmod 750 "${neues}"{,/wip}
+chown root:root "${neues}"{,/wip}
+if [ -z "${rsyncShell}" ]; then
+  preConnectHook
+  if [ -z "${Quelle#*@*:/}" ]; then
+    ssh "-${ipVer}" "${Quelle%:/}" '
+      pacman-conf Architecture
+      find /var/lib/pacman/local -name desc -exec cat {} +
+    ' \
+    | {
+      read -r arch
+      sed -n '
+        /^%\(NAME\|VERSION\|ARCH\)%/ {
+          N
+          s/\n/ /
+          p
+        }
+      ' \
+      | sed '
+        N
+        N
+        s@^%NAME% \(\S\+\)\n%VERSION% \(\S\+\)\n%ARCH% \(\S\+\)$@\1-\2-\3.pkg.tar.zst@
+        t
+        w /dev/stderr
+        d
+      ' \
+      | while read -r file; do
+        cache_file='/var/cache/pacman/pkg/'"${file}"
+        if [ ! -f "${cache_file}" ]; then
+          case "${arch}" in
+            'x86_64')
+              for url in \
+                'https://mirror.f4st.host/archlinux/pool/packages/'"${file}" \
+                'https://archive.archlinux.org/packages/'"${file:0:1}"'/'"${file%-*}"'/'"${file}"; do
+                curl -Lo "${cache_file}" "${url}" || continue
+                tar --zstd -tf "${cache_file}" >/dev/null 2>&1 && break
+              done
+            ;;
+            'i486'|'i686'|'pentium4')
+              for url in \
+                'https://mirror.archlinux32.org/pool/'"${file}" \
+                'https://archive.archlinux32.org/packages/'"${file:0:1}"'/'"${file%-*}"'/'"${file}"; do
+                curl -Lo "${cache_file}" "${url}" || continue
+                tar --zstd -tf "${cache_file}" >/dev/null 2>&1 && break
+              done
+            ;;
+            *)
+              for url in \
+                'https://mirror.archlinux.org/'"${arch}"'/'{extra,community,core,alarm,aur}'/'"${file}"; do
+                curl -Lo "${cache_file}" "${url}" || continue
+                tar --zstd -tf "${cache_file}" >/dev/null 2>&1 && break
+              done
+            ;;
+          esac
+        fi
+        if [ -f "${cache_file}" ]; then
+          tar -C "${neues:?}/wip/" --zstd -xkf "${cache_file}"
+        fi
+      done
+    }
+  fi
+  rsync ${rsyncOptions} \
+    ${linkdests} \
+    ${excludeArgs} \
+    ${Quelle} "${neues}/wip/"
+  sleep 1
+  preConnectHook
+  rsync ${Quelle}
+else
+  preConnectHook
+  rsync "${rsyncShell}" \
+    ${rsyncOptions} \
+    ${linkdests} \
+    ${excludeArgs} \
+    ${Quelle} "${neues}/wip/"
+  sleep 1
+  preConnectHook
+  rsync "${rsyncShell}" ${Quelle}
+fi
+erg=$?
+
+[ -n "${backgroundPid}" ] && kill "${backgroundPid}"
+
+if [ ${erg} -eq 0 ] || [ ${erg} -eq 24 ] && ! rmdir "${neues}/wip" 2>/dev/null; then
+  chmod o-rwx "${neues}/wip"
+  neueres_Datum="${Basis}/$(date "+%Y_%m_%d")"
+  if [ ! -e "${neueres_Datum}" ]; then
+    neues_Datum="${neueres_Datum}"
+  fi
+  mv "${neues}/wip" "${neues_Datum}"
+  rmdir "${neues}"
+  rm "${pidFile}"
+else
+  rm "${pidFile}"
+  exit 11
+fi