iankelling.org Git - lnf/blob - lnf

   1 #!/bin/bash
   2 # Copyright (C) 2014-2016 Ian Kelling
   3 # This program is under GPL v. 3 or later, see <http://www.gnu.org/licenses/>
   4
   5 lnf() {
   6     local help="Usage:
   7        lnf -T TARGET LINK_NAME     (1st form)
   8        lnf TARGET                  (2nd form)
   9        lnf TARGET... DIRECTORY     (3rd form)
  10 Create symlinks forcefully
  11
  12 Removes existing files using trash-put or rm -rf if it is not available,
  13 or trash-put fails due to a limitation such as a cross-filesystem link.
  14 Create directory if needed. Slightly more restrictive arguments than ln.
  15
  16 In the 1st form, create a link to TARGET with the name LINK_NAME.  In the 2nd
  17 form, create a link to TARGET in the current directory.  In the 3rd form, create
  18 links to each TARGET in DIRECTORY."
  19
  20     if [[ $1 == --help || $# -eq 0 ]]; then
  21         echo "$help"
  22         return 0
  23     fi
  24
  25     local nodir
  26     if [[ $1 == -T ]]; then
  27         nodir=-T
  28         shift
  29         if (( $# != 2 )); then
  30             echo "lnf error: expected 2 arguments with -T flag. Got $#"
  31             return 1
  32         fi
  33     fi
  34
  35     local reset_extglob=false
  36     ! shopt extglob >/dev/null && reset_extglob=true
  37     shopt -s extglob
  38
  39
  40     local x ret prefix dir to_remove
  41     local mkdir=false
  42
  43     to_remove=()
  44     if [[ $nodir ]]; then
  45         dir="$(dirname "$2")"
  46         if [[ -e $2 || -L $2 ]]; then
  47             to_remove+=("$2")
  48         elif [[ ! -d $dir ]]; then
  49             mkdir=true
  50             if [[ -e $dir || -L $dir ]]; then
  51                 to_remove+=("$dir")
  52             fi
  53         fi
  54     elif (( $# >= 2 )); then
  55         if [[ -d ${!#} ]]; then
  56             prefix="${!#}/" # last arg
  57             for x in "${@:1:$(( $# - 1 ))}"; do # all but last arg
  58                 # Remove 1 or more trailing slashes, using.
  59                 x="${x%%+(/)}"
  60                 # remove any leading directory components, add prefix
  61                 x="$prefix/${x##*/}"
  62                 [[ -e "$x" || -L "$x" ]] && to_remove+=("$x")
  63             done
  64         else
  65             if ! mkdir -p "${!#}"; then
  66                 echo "lnf error: failed to make directory ${!#}"
  67                 return 1
  68             fi
  69         fi
  70     elif  [[ $# -eq 1 ]]; then
  71         [[ -e "${1##*/}" || -L "${1##*/}" ]] && to_remove+=("${1##*/}")
  72     fi
  73     if (( ${#to_remove[@]} >= 1 )); then
  74         if type -P trash-put >/dev/null; then
  75             trash-put -- "${to_remove[@]}" || ret=$?
  76             # trash-put will fail to trash a link that goes across filesystems (72),
  77             # and for empty files (74)
  78             # so revert to rm -rf in that case
  79             if [[ $ret == 72 ]]; then
  80                 echo "$0: using rm -rf to overcome cross filesystem trash-put limitation"
  81                 rm -rf -- "${to_remove[@]}"
  82             elif [[ $ret == 74 ]]; then
  83                 echo "$0: using rm -rf to overcome empty file & hardlink trash-put limitation"
  84                 rm -rf -- "${to_remove[@]}"
  85             elif [[ $ret && $ret != 0 ]]; then
  86                 return $x
  87             fi
  88         else
  89             rm -rf -- "${to_remove[@]}"
  90         fi
  91     fi
  92
  93     $reset_extglob && shopt -u extglob
  94
  95     if $mkdir; then
  96         if ! mkdir -p "$(dirname "$2")"; then
  97             echo "lnf error: failed to make directory $(dirname "$2")"
  98             return 1
  99         fi
 100     fi
 101
 102     ln -s $nodir -- "$@"
 103 }
 104 lnf "$@"