src/functions/functions.editor

   1 #!/bin/bash
   2 ###############################################################################
   3 #                                                                             #
   4 # IPFire.org - A linux based firewall                                         #
   5 # Copyright (C) 2017 IPFire Network Development Team                          #
   6 #                                                                             #
   7 # This program is free software: you can redistribute it and/or modify        #
   8 # it under the terms of the GNU General Public License as published by        #
   9 # the Free Software Foundation, either version 3 of the License, or           #
  10 # (at your option) any later version.                                         #
  11 #                                                                             #
  12 # This program is distributed in the hope that it will be useful,             #
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of              #
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
  15 # GNU General Public License for more details.                                #
  16 #                                                                             #
  17 # You should have received a copy of the GNU General Public License           #
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 editor_find_best() {
  23         # Open a file with the best available editor
  24         assert [ $# -eq 1 ]
  25
  26         local file=${1}
  27         local ret
  28
  29         for editor in ${EDITOR} vim vi; do
  30                 ${editor} "${file}"
  31                 ret=${?}
  32
  33                 case "${ret}" in
  34                         ${EXIT_OK})
  35                                 return ${EXIT_OK}
  36                                 ;;
  37
  38                         ${EXIT_COMMAND_NOT_FOUND})
  39                                 continue
  40                                 ;;
  41
  42                         *)
  43                                 return ${ret}
  44                                 ;;
  45                 esac
  46         done
  47
  48         error "Unable to find a working editor"
  49
  50         return ${EXIT_COMMAND_NOT_FOUND}
  51 }
  52
  53 editor() {
  54         local file="${1}"
  55         assert isset file
  56
  57         if [ ! -f ${file} ] || [ ! -w ${file} ]; then
  58                 error "${file} is not valid file or is not writeable"
  59                 return ${EXIT_ERROR}
  60         fi
  61
  62         lock "${file}.lock" __editor "$@"
  63 }
  64
  65 __editor() {
  66         # This function open a file for editing and take care of all preperation and postprocessing
  67         assert [ $# -ge 1 ]
  68
  69         local file="${1}"
  70         local check_func="${2}"
  71
  72         # create a temporary file
  73         local temp_file="$(mktemp)"
  74
  75         if ! [ -f "${temp_file}" ]; then
  76                 error "Cannot create temporary file"
  77         fi
  78
  79         # copy the content into this temporary file
  80         cp -f "${file}" "${temp_file}"
  81
  82         # edit the file
  83         if ! editor_find_best "${temp_file}"; then
  84                 error "Could not edit ${file}"
  85
  86                 # Delete temporary file
  87                 file_delete "${temp_file}"
  88
  89                 return ${EXIT_ERROR}
  90         fi
  91
  92         # run the check if we have one
  93         if isset check_func && ! editor_check "${check_func}" "${temp_file}"; then
  94                 # Delete temporary file
  95                 file_delete "${temp_file}"
  96
  97                 return ${EXIT_ERROR}
  98         fi
  99
 100         # copy the changes back
 101         cp -f "${temp_file}" "${file}"
 102
 103         # Delete temporary file
 104         file_delete "${temp_file}"
 105 }
 106
 107 editor_check() {
 108         # Execute the check function to make sure that the changes does not break anything
 109         local check_func="${1}"
 110         shift
 111
 112         # Execute the check function
 113         "${check_func}" "$@"
 114         local ret="${?}"
 115
 116         case "${ret}" in
 117                 # OK
 118                 ${EXIT_OK}|${EXIT_TRUE})
 119                         log DEBUG "Check succeeded"
 120                         return ${EXIT_TRUE}
 121                         ;;
 122
 123                 # Error
 124                 ${EXIT_ERROR}|${EXIT_FALSE})
 125                         log CRITICAL "Check failed"
 126                         return ${EXIT_FALSE}
 127                         ;;
 128
 129                 # Command not found
 130                 ${EXIT_COMMAND_NOT_FOUND})
 131                         log CRITICAL "Check function '${check_func}' was not found"
 132                         return ${EXIT_FALSE}
 133                         ;;
 134         esac
 135
 136         log CRITICAL "Unhandled exit code for '${check_func}': ${ret}"
 137         return ${EXIT_ERROR}
 138 }