Add editor functions

Signed-off-by: Jonatan Schlag <jonatan.schlag@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/Makefile.am b/Makefile.am
index 61c520c862608ac405ecdf643ce69f99ec467c5b..32e71660609504801da01e9a23a6440f96826e46 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -121,6 +121,7 @@ dist_network_SCRIPTS = \
        src/functions/functions.distro \
        src/functions/functions.dns \
        src/functions/functions.dummy \
+       src/functions/functions.editor \
        src/functions/functions.ethernet \
        src/functions/functions.firewall \
        src/functions/functions.firewall-policy \

diff --git a/src/functions/functions.editor b/src/functions/functions.editor
new file mode 100644 (file)
index 0000000..f362a6f
--- /dev/null
+++ b/src/functions/functions.editor
@@ -0,0 +1,149 @@
+#!/bin/bash
+###############################################################################
+#                                                                             #
+# IPFire.org - A linux based firewall                                         #
+# Copyright (C) 2017 IPFire Network Development Team                          #
+#                                                                             #
+# This program is free software: you can redistribute it and/or modify        #
+# it under the terms of the GNU General Public License as published by        #
+# the Free Software Foundation, either version 3 of the License, or           #
+# (at your option) any later version.                                         #
+#                                                                             #
+# This program is distributed in the hope that it will be useful,             #
+# but WITHOUT ANY WARRANTY; without even the implied warranty of              #
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
+# GNU General Public License for more details.                                #
+#                                                                             #
+# You should have received a copy of the GNU General Public License           #
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
+#                                                                             #
+###############################################################################
+
+editor_cleanup() {
+       # Cleanup after a file was edited
+       assert [ $# -eq 2 ]
+
+       local file=${1}
+       local temp_file=${2}
+
+       lock_release "${file}.lock"
+       rm -f ${temp_file}
+}
+
+editor_find_best() {
+       # Open a file with the best available editor
+       assert [ $# -eq 1 ]
+
+       local file=${1}
+       local ret
+
+       for editor in ${EDITOR} vim vi; do
+               ${editor} "${file}"
+               ret=${?}
+
+               case "${ret}" in
+                       ${EXIT_OK})
+                               return ${EXIT_OK}
+                               ;;
+
+                       ${EXIT_COMMAND_NOT_FOUND})
+                               continue
+                               ;;
+
+                       *)
+                               return ${ret}
+                               ;;
+               esac
+       done
+
+       error "Unable to find a working editor"
+
+       return ${EXIT_COMMAND_NOT_FOUND}
+}
+
+editor() {
+       # This function open a file for editing and take care of all preperation and postprocessing
+       assert [ $# -ge 1 ]
+
+       local file=${1}
+       if [ ! -f ${file} ] || [ ! -w ${file} ]; then
+               error "${file} is not valid file or is not writeable"
+               return ${EXIT_ERROR}
+       fi
+
+       local check_func=${2}
+
+       # check if the file is locked
+       if lock_exists "${file}.lock"; then
+               error "Cannot edit ${file} because it is locked"
+               return ${EXIT_ERROR}
+       fi
+
+       # lock the file
+       if ! lock_acquire "${file}.lock"; then
+               error "Cannot lock file ${file}"
+               return ${EXIT_ERROR}
+       fi
+
+       # create a temporary file
+       local temp_file=$(mktemp)
+
+       if ! [ -f "${temp_file}" ]; then
+               error "Cannot create temporary file"
+       fi
+
+       # copy the content into this temporary file
+       cp -f "${file}" "${temp_file}"
+
+       # edit the file
+       if ! editor_find_best "${temp_file}"; then
+               error "Could not edit ${file}"
+               # cleanup
+               editor_cleanup "${file}" "${temp_file}"
+       fi
+
+       # run the check if we have one
+       if isset check_func && ! editor_check "${check_func}" "${temp_file}"; then
+               return ${EXIT_ERROR}
+       fi
+
+       # copy the changes back
+       cp -f "${temp_file}" "${file}"
+
+       # cleanup
+       editor_cleanup "${file}" "${temp_file}"
+
+}
+
+editor_check() {
+       # Execute the check function to make sure that the changes does not break anything
+       local check_func="${1}"
+       shift
+
+       # Execute the check function
+       "${check_func}" $@
+       local ret="${?}"
+
+       case "${ret}" in
+               # OK
+               ${EXIT_OK}|${EXIT_TRUE})
+                       log DEBUG "Check succeeded"
+                       return ${EXIT_TRUE}
+                       ;;
+
+               # Error
+               ${EXIT_ERROR}|${EXIT_FALSE})
+                       log CRITICAL "Check failed"
+                       return ${EXIT_FALSE}
+                       ;;
+
+               # Command not found
+               ${EXIT_COMMAND_NOT_FOUND})
+                       log CRITICAL "Check function '${check_func}' was not found"
+                       return ${EXIT_FALSE}
+                       ;;
+       esac
+
+       log CRITICAL "Unhandled exit code for '${check_func}': ${ret}"
+       return ${EXIT_ERROR}
+}