iankelling.org Git - cedit/blob - cedit

   1 #!/bin/bash
   2 # Copyright (C) 2016 Ian Kelling
   3
   4 # Licensed under the Apache License, Version 2.0 (the "License");
   5 # you may not use this file except in compliance with the License.
   6 # You may obtain a copy of the License at
   7
   8 #     http://www.apache.org/licenses/LICENSE-2.0
   9
  10 # Unless required by applicable law or agreed to in writing, software
  11 # distributed under the License is distributed on an "AS IS" BASIS,
  12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 # See the License for the specific language governing permissions and
  14 # limitations under the License.
  15
  16 cedit() {
  17   local help="Usage: [-h|--help ] [-v] [SECTION_NAME] FILE
  18 Create/modify a section in a config file
  19
  20 Returns 1 if the file is modified by this command, 2 or higher
  21 for other problems.
  22
  23 The section is #comment delimited. Reads STDIN for the contents of the
  24 section. Without SECTION_NAME, it acts on a global unnamed
  25 section. cedit is short for config edit.
  26
  27 -v         Verbose
  28 -b         Keep backup file
  29 -h|--help  Help"
  30   local s diff name init
  31   local file_dir="$(dirname "$file")"
  32   local exists=true
  33   local verbose=false
  34   local backup=false
  35
  36   case $1 in
  37     -b) backup=true; shift ;;
  38     -v) verbose=true; shift ;;
  39     -h|--help) echo "$help"; return ;;
  40   esac
  41
  42   if (( $# == 2 )); then
  43     name=": $1"
  44     shift
  45   fi
  46
  47   local file="$1"
  48   local file_name="${file##*/}"
  49
  50   local begin="#_#_# start delimiter of cedit section$name. do not modify. #_#_#"
  51   local end="#_#_# end delimiter of cedit section$name. do not modify. #_#_#"
  52
  53   if [[ ! -e $file_dir ]]; then
  54     if ! mkdir -p $file_dir; then
  55       s=sudo
  56       $s mkdir -p $file_dir || return 2
  57     fi
  58   fi
  59   if [[ ! -e $file ]]; then
  60     exists=false
  61     if ! $s touch $file; then
  62       s=sudo
  63       $s touch $file || return 2
  64     fi
  65   fi
  66
  67   [[ -w $file ]] || s=sudo
  68
  69
  70   local in_section=false
  71   if $exists; then
  72     local tailn=1
  73     local temp="$(mktemp -d)/$file_name"
  74     cp "$file" "$temp"
  75     cp /dev/null "$file"
  76     while IFS= read -r line; do
  77       tailn=$(( tailn + 1 ))
  78       if [[ $line == "$begin" ]]; then
  79         in_section=true;
  80         break
  81       fi
  82       printf '%s\n' "$line" >> $file
  83     done < "$temp"
  84   fi
  85
  86   IFS= read -d '' -n 1 -r init
  87   if [[ $init ]]; then
  88     $s tee -a "$file" >/dev/null <<<"$begin"
  89     printf '%s' "$init" | $s tee -a "$file" >/dev/null
  90     $s tee -a "$file" >/dev/null
  91     $s tee -a "$file" >/dev/null <<<"$end"
  92   fi
  93
  94   if $exists && $in_section; then
  95     while IFS= read -r line; do
  96       if [[ $line == "$begin" ]]; then
  97         in_section=true;
  98       fi
  99       if ! $in_section; then
 100         printf '%s\n' "$line" >> $file
 101       fi
 102       if [[ $line == $end ]]; then
 103         in_section=false;
 104       fi
 105     done < <(tail -n +$tailn "$temp")
 106   fi
 107
 108
 109   if ! $exists; then
 110     ret=1
 111     if $verbose; then
 112       echo "New file $file:"
 113       cat "$file"
 114     fi
 115   elif type -t diff &>/dev/null; then
 116     diff=$(diff -u "$temp" "$file")
 117     ret=$?
 118     if (( $ret )); then
 119       echo "backup of original at $temp"
 120       echo diff -u "$temp" "$file":
 121       echo "$diff"
 122       #elif $debug; then
 123       #  echo "No changes made to $file"
 124     fi
 125   else
 126     # for systems like openwrt which don't have diff
 127     diff=$(cmp "$temp" "$file")
 128     ret=$?
 129     if $verbose; then
 130       echo "$diff"
 131     fi
 132   fi
 133   if ! $backup; then
 134     rm -r $"$temp"
 135   fi
 136   return $ret
 137 }
 138 cedit "$@"