user-tools/symlinks-analyze

   1 #!/bin/bash
   2
   3 true <<EOF
   4 =pod
   5
   6 =head1 NAME
   7
   8 symlinks-analyze - Discover where symlinks point at, recursively
   9
  10 =cut
  11
  12 EOF
  13
  14
  15 set -e
  16 set -u
  17 . /usr/lib/tool/bash-utils
  18 shopt -s extglob
  19 unset CDPATH
  20 unset CDPATH
  21 set +e
  22
  23 notrailingslash()
  24 {
  25         local x=$1
  26         if [ "$x" = / ]; then echo /; return; fi
  27         echo ${x/%+(\/)/}
  28 }
  29
  30 show_abs_path()
  31 {
  32         local path=$1 logical_path=$2
  33         if [ $show_abs_path ]
  34         then
  35                 if [ "${path:0:1}" = / ]
  36                 then
  37                         return
  38                 fi
  39                 echo -n " [$logical_path]"
  40         fi
  41 }
  42
  43 show_realpath()
  44 {
  45         local path=$1
  46         if [ $show_realpath ]
  47         then
  48                 local realpath=`readlink -n -f "$path"`
  49                 if [ "$realpath" != "$path" ]
  50                 then
  51                         echo -n " ($realpath)"
  52                 fi
  53         fi
  54 }
  55
  56 logical_dirname()
  57 {
  58         local path=$1
  59         local dir=$(dirname "$path")
  60         cd "$dir" && pwd || kill -ABRT $$
  61         # kill ourself to prevent bad data at the caller,
  62         # so the caller does not need to set errexit
  63 }
  64
  65 logical_path()
  66 {
  67         local path=$1
  68         local dirname=`logical_dirname "$path"`
  69         if [ "$dirname" != / ]; then dirname=$dirname/; fi
  70         local basename=$(basename "$path")
  71         echo "$dirname$basename"
  72 }
  73
  74
  75 show_abs_path=''
  76 show_realpath=''
  77 show_parents=''
  78 skip_non_symlinks=''
  79
  80
  81 while [ $# -gt 0 ]
  82 do
  83         case "$1" in
  84         --)     shift; break;;
  85         --help)
  86                 echo "Usage: symlinks-analyze [OPTIONS] <PATH> [<PATH> [...]]"
  87                 echo "OPTIONS:"
  88                 echo " -a, --absolute-path      shown in [ brackets ]"
  89                 echo " -r, --real-path          shown in ( brackets )"
  90                 echo " -p, --parents            analyze parent directories of any traversed path too"
  91                 echo " -s, --skip-non-symlinks"
  92                 exit;;
  93         -a|--abs|--absolute|--abs-path|--absolute-path)
  94                 show_abs_path=1;;
  95         -p|--parent|--parents)
  96                 show_parents=1;;
  97         -r|--realpath|--real-path)
  98                 show_realpath=1;;
  99         -s|--skip-non-symlinks)
 100                 skip_non_symlinks=1;;
 101         -*)     echo "$0: unknown option: $1" >&2
 102                 exit -1;;
 103         *)      break;;
 104         esac
 105         shift
 106 done
 107
 108
 109 declare -a paths_to_analyze=("$@")
 110 declare -a paths_analyzed=()
 111 starting_wd=`pwd`
 112
 113 while [ ${#paths_to_analyze[@]} -gt 0 ]
 114 do
 115         declare -a visited=()
 116         show_this_analysis=yes
 117
 118         path_to_analyze=${paths_to_analyze[0]}
 119         path=`notrailingslash "$path_to_analyze"`
 120
 121         if [ $skip_non_symlinks ]
 122         then
 123                 if [ ! -L "$path" ]
 124                 then
 125                         show_this_analysis=no
 126                 fi
 127         fi
 128
 129         if [ ! -e "$path" -a ! -L "$path" ]
 130         then
 131                 # neither an actual existing file nor a broken symlink
 132                 warnx "$path: not found"
 133                 show_this_analysis=no
 134         fi
 135
 136         if [ $show_this_analysis = yes ]
 137         then
 138                 echo -n "$path"
 139
 140                 logical_path=`logical_path "$path"`
 141                 show_abs_path "$path" "$logical_path"
 142                 show_realpath "$path"
 143                 visited+=("$logical_path")
 144
 145                 while true
 146                 do
 147                         if [ $show_parents ]
 148                         then
 149                                 parent=`logical_dirname "$path"`
 150                                 if [ "$parent" != / ]
 151                                 then
 152                                         if ! in_list "$parent" "${paths_to_analyze[@]}" "${paths_analyzed[@]}"
 153                                         then
 154                                                 paths_to_analyze+=("$parent")
 155                                         fi
 156                                 fi
 157                         fi
 158
 159                         if [ ! -L "$path" ]
 160                         then
 161                                 break
 162                         fi
 163
 164                         set -e
 165                         target=`readlink "$path"`
 166                         dir=`dirname "$path"`
 167                         cd "$dir"
 168                         set +e
 169
 170                         echo -n " -> $target"
 171                         logical_path=`logical_path "$target"`
 172                         show_abs_path "$target" "$logical_path"
 173
 174                         if in_list "$logical_path" "${visited[@]}"
 175                         then
 176                                 break
 177                         fi
 178                         visited+=("$logical_path")
 179
 180                         path=$target
 181                         path=`notrailingslash "$path"`
 182                 done
 183
 184                 echo ";"
 185         fi
 186
 187         set -e
 188         cd "$starting_wd"
 189         set +e
 190
 191         array_shift paths_to_analyze >/dev/null
 192         paths_analyzed+=("$path_to_analyze")
 193 done