Merge branch 'type/openwrt-uci' into 'master'

Add OpenWrt UCI types

See merge request ungleich-public/cdist!886

cdist/conf/type/__uci/explorer/state

@@ -0,0 +1,110 @@
+#!/bin/sh
+#
+# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+# This explorer retrieves the current state of the configuration option
+# The output of this explorer is one of these values:
+#   present
+#     The configuration option is present and has the value of the
+#     parameter --value.
+#   absent
+#     The configuration option is not defined.
+#   different
+#     The configuration option is present but has a different value than the
+#     parameter --value.
+#   rearranged
+#     The configuration option is present (a list) and has the same values as
+#     the parameter --value, but in a different order.
+
+RS=$(printf '\036')
+
+option=${__object_id:?}
+
+values_is=$(uci -s -N -d "${RS}" get "${option}" 2>/dev/null) || {
+	echo absent
+	exit 0
+}
+
+if test -f "${__object:?}/parameter/value"
+then
+	should_file="${__object:?}/parameter/value"
+else
+	should_file='/dev/null'
+fi
+
+
+# strip off trailing newline
+printf '%s' "${values_is}" \
+| awk '
+function unquote(s) {
+	# simplified dequoting of single quoted strings
+	if (s ~ /^'\''.*'\''$/) {
+		s = substr(s, 2, length(s) - 2)
+		sub(/'"'\\\\''"'/, "'\''", s)
+	}
+	return s
+}
+
+BEGIN {
+	state = "present"  # assume all is fine
+}
+NR == FNR {
+	# memoize "should" state
+	should[FNR] = $0
+	should_count++
+
+	# go to next line (important!)
+	next
+}
+
+# compare "is" state
+
+{ $0 = unquote($0) }
+
+$0 == should[FNR] { next }
+
+FNR > should_count {
+	# there are more "is" records than "should" -> definitely different
+	state = "different"
+	exit
+}
+
+{
+	# see if we can find the value somewhere in should
+	for (i in should) {
+		if ($0 == should[i]) {
+			# ... value found -> rearranged
+			# FIXME: Duplicate values are not properly handled here. Do they matter?
+			state = "rearranged"
+			next
+		}
+	}
+
+	state = "different"
+	exit
+}
+
+END {
+	if (FNR < should_count) {
+		# "is" was shorter than "should" -> different
+		state = "different"
+	}
+
+	print state
+}
+' "${should_file}" RS="${RS}" -

cdist/conf/type/__uci/files/functions.sh

@@ -0,0 +1,73 @@
+# -*- mode: sh; indent-tabs-mode: t -*-
+
+in_list() {
+	printf '%s\n' "$@" | { grep -qxF "$(read -r ndl; echo "${ndl}")"; }
+}
+
+quote() {
+	for _arg
+	do
+		shift
+		if test -n "$(printf %s "${_arg}" | tr -d -c '\t\n \042-\047\050-\052\073-\077\133\\`|~' | tr -c '' '.')"
+		then
+			# needs quoting
+			set -- "$@" "$(printf "'%s'" "$(printf %s "${_arg}" | sed -e "s/'/'\\\\''/g")")"
+		else
+			set -- "$@" "${_arg}"
+		fi
+	done
+	unset _arg
+
+	# NOTE: Use printf because POSIX echo interprets escape sequences
+	printf '%s' "$*"
+}
+
+uci_cmd() {
+	# Usage: uci_cmd [UCI ARGUMENTS]...
+	mkdir -p "${__object:?}/files"
+	printf '%s\n' "$(quote "$@")" >>"${__object:?}/files/uci_batch.txt"
+}
+
+uci_validate_name() {
+	# like util.c uci_validate_name()
+	test -n "$*" && test -z "$(echo "$*" | tr -d '[:alnum:]_')"
+}
+
+uci_validate_tuple() (
+	tok=${1:?}
+	case $tok
+	in
+		(*.*.*)
+			# check option
+			option=${tok##*.}
+			uci_validate_name "${option}" || {
+				printf 'Invalid option: %s\n' "${option}" >&2
+				return 1
+			}
+			tok=${tok%.*}
+			;;
+		(*.*)
+			# no option (section definition)
+			;;
+		(*)
+			printf 'Invalid tuple: %s\n' "$1" >&2
+			return 1
+			;;
+	esac
+
+	case ${tok#*.}
+	in
+		(@*) section=$(expr "${tok#*.}" : '@\(.*\)\[-*[0-9]*\]$') ;;
+		(*)  section=${tok#*.} ;;
+	esac
+	uci_validate_name "${section}" || {
+		printf 'Invalid section: %s\n' "${1#*.}" >&2
+		return 1
+	}
+
+	config=${tok%%.*}
+	uci_validate_name "${config}" || {
+		printf 'Invalid config: %s\n' "${config}" >&2
+		return 1
+	}
+)

cdist/conf/type/__uci/files/uci_apply.sh

@@ -0,0 +1,43 @@
+changes=$(uci changes)
+
+if test -n "${changes}"
+then
+	echo 'Uncommited UCI changes were found on the target:'
+	printf '%s\n\n' "${changes}"
+	echo 'This can be caused by manual changes or due to a previous failed run.'
+	echo 'Please investigate the situation, revert or commit the changes, and try again.'
+	exit 1
+fi >&2
+
+check_errors() {
+	# reads stdin and forwards non-empty lines to stderr.
+	# returns 0 if stdin is empty, else 1.
+	! grep -e . >&2
+}
+
+commit() {
+	uci commit
+}
+
+rollback() {
+	printf '\nAn error occurred when trying to commit UCI transaction!\n' >&2
+
+	uci changes \
+	| sed -e 's/^-//' -e 's/\..*\$//' \
+	| sort -u \
+	| while read -r _package
+	  do
+		  uci revert "${_package}"
+		  echo "${_package}"  # for logging
+	  done \
+	| awk '
+	  BEGIN { printf "Reverted changes in: " }
+	  { printf "%s%s", (FNR > 1 ? ", " : ""), $0 }
+	  END { printf "\n" }' >&2
+
+	return 1
+}
+
+uci_apply() {
+	uci batch 2>&1 | check_errors && commit || rollback
+}

cdist/conf/type/__uci/gencode-remote

@@ -0,0 +1,101 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# shellcheck source=files/functions.sh
+. "${__type:?}/files/functions.sh"
+
+state_is=$(cat "${__object:?}/explorer/state")
+state_should=$(cat "${__object:?}/parameter/state")
+
+config=${__object_id:?}
+uci_validate_tuple "${config}"
+
+
+case ${state_should}
+in
+	(present)
+		if in_list "${state_is}" 'present' 'rearranged'
+		then
+			# NOTE: order is ignored so rearranged is also fine.
+			exit 0
+		fi
+
+		# Determine type
+		type=$(cat "${__object:?}/parameter/type" 2>/dev/null || true)
+		case ${type}
+		in
+			(option|list) ;;
+			('')
+				# Guess type by the number of values
+				test "$(wc -l "${__object:?}/parameter/value")" -gt 1 \
+					 && type=list \
+					 || type=option
+				;;
+			(*)
+				printf 'Invalid --type: %s\n' "${type}" >&2
+				exit 1
+				;;
+		esac
+
+		case ${type}
+		in
+			(list)
+				printf 'set_list %s\n' "${config}" >>"${__messages_out:?}"
+
+				if test "${state_is}" != 'absent'
+				then
+					uci_cmd delete "${config}"
+				fi
+
+				while read -r value
+				do
+					uci_cmd add_list "${config}"="${value}"
+				done <"${__object:?}/parameter/value"
+				;;
+			(option)
+				printf 'set %s\n' "${config}" >>"${__messages_out:?}"
+
+				value=$(cat "${__object:?}/parameter/value")
+				uci_cmd set "${config}"="${value}"
+				;;
+		esac
+		;;
+	(absent)
+		if in_list "${state_is}" 'absent'
+		then
+			exit 0
+		fi
+
+		printf 'delete %s\n' "${config}" >>"${__messages_out:?}"
+		uci_cmd delete "${config}"
+		;;
+	(*)
+		printf 'Invalid --state: %s\n' "${state_should}" >&2
+		exit 1
+		;;
+esac
+
+if test -s "${__object:?}/files/uci_batch.txt"
+then
+	cat "${__type:?}/files/uci_apply.sh"
+	printf "uci_apply <<'EOF'\n"
+	cat "${__object:?}/files/uci_batch.txt"
+	printf '\nEOF\n'
+fi

cdist/conf/type/__uci/man.rst

@@ -0,0 +1,78 @@
+cdist-type__uci(7)
+==================
+
+NAME
+----
+cdist-type__uci - Manage configuration values in UCI
+
+
+DESCRIPTION
+-----------
+This cdist type can be used to alter configuration options in OpenWrt's
+Unified Configuration Interface (UCI) system.
+
+
+REQUIRED PARAMETERS
+-------------------
+value
+    The value to be set. Can be used multiple times.
+    This parameter is ignored if ``--state`` is ``absent``.
+
+    Due to the way cdist handles arguments, values **must not** contain newline
+    characters.
+
+    Values do not need special quoting for UCI. The only requirement is that the
+    value is passed to the type as a single shell argument.
+
+OPTIONAL PARAMETERS
+-------------------
+state
+    ``present`` or ``absent``, defaults to ``present``.
+type
+    If the type should generate an option or a list.
+    One of: ``option`` or ``list``.
+    Defaults to auto-detect based on the number of ``--value`` parameters.
+
+
+BOOLEAN PARAMETERS
+------------------
+None.
+
+
+EXAMPLES
+--------
+
+.. code-block:: sh
+
+    # Set the system hostname
+    __uci system.@system[0].hostname --value 'OpenWrt'
+
+    # Set DHCP option 252: tell DHCP clients to not ask for proxy information.
+    __uci dhcp.lan.dhcp_option --type list --value '252,"\n"'
+
+    # Enable NTP and NTPd (each is applied individually)
+    __uci system.ntp.enabled --value 1
+    __uci system.ntp.enable_server --value 1
+    __uci system.ntp.server --type list \
+        --value '0.openwrt.pool.ntp.org' \
+        --value '1.openwrt.pool.ntp.org' \
+        --value '2.openwrt.pool.ntp.org' \
+        --value '3.openwrt.pool.ntp.org'
+
+
+SEE ALSO
+--------
+- https://openwrt.org/docs/guide-user/base-system/uci
+
+
+AUTHORS
+-------
+Dennis Camera <dennis.camera@ssrq-sds-fds.ch>
+
+
+COPYING
+-------
+Copyright \(C) 2020 Dennis Camera. 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.

cdist/conf/type/__uci/manifest

@@ -0,0 +1,51 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+os=$(cat "${__global:?}/explorer/os")
+
+state_should=$(cat "${__object:?}/parameter/state")
+
+case ${os}
+in
+	(openwrt)
+		# okay
+		;;
+	(*)
+		printf "Your operating system (%s) is currently not supported by this type (%s)\n" "${os}" "${__type##*/}" >&2
+		printf "Please contribute an implementation for it if you can.\n" >&2
+		exit 1
+		;;
+esac
+
+case ${state_should}
+in
+	(present)
+		test -s "${__object:?}/parameter/value" || {
+			echo 'The parameter --value is required.' >&2
+			exit 1
+		}
+		;;
+	(absent)
+		;;
+	(*)
+		printf 'Invalid --state: %s\n' "${state_should}" >&2
+		exit 1
+		;;
+esac

cdist/conf/type/__uci/parameter/default/state

@@ -0,0 +1 @@
+present

cdist/conf/type/__uci/parameter/optional

@@ -0,0 +1,2 @@
+state
+type

cdist/conf/type/__uci/parameter/optional_multiple

@@ -0,0 +1 @@
+value

cdist/conf/type/__uci_section/explorer/match

@@ -0,0 +1,103 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+# This explorer determines the "prefix" of the --type section matching --match
+# if set, or __object_id otherwise.
+
+RS=$(printf '\036')
+NL=$(printf '\n '); NL=${NL% }
+
+squote_values() {
+	sed -e '/=".*"$/{s/="/='\''/;s/"$/'\''/}' \
+	    -e "/='.*'$/"'!{s/=/='\''/;s/$/'\''/}'
+}
+count_lines() (
+	IFS=${NL?}
+	# shellcheck disable=SC2048,SC2086
+	set -f -- $*; echo $#
+)
+
+echo "${__object_id:?}" | grep -q -e '^[^.]\{1,\}\.[^.]\{1,\}$' || {
+	echo 'Section identifiers are a package and section name separated by a "." (period).' >&2
+	exit 1
+}
+
+test -s "${__object:?}/parameter/match" || {
+	# If no --match is given, we take the __object_id as the section identifier.
+	echo "${__object_id:?}"
+	exit 0
+}
+test -s "${__object:?}/parameter/type" || {
+	echo 'Parameters --match and --type must be used together.' >&2
+	exit 1
+}
+
+sect_type_param=$(cat "${__object:?}/parameter/type")
+expr "${sect_type_param}" : '[^.]\{1,\}\.[^.]\{1,\}$' >/dev/null 2>&1 || {
+	echo 'Section types are a package name and section type separated by a "." (period).' >&2
+	exit 1
+}
+package_filter=${sect_type_param%%.*}
+section_filter=${sect_type_param#*.}
+
+# Find by --match
+# NOTE: Apart from section types all values are printed in single quotes by uci show.
+match=$(head -n 1 "${__object:?}/parameter/match" | squote_values)
+
+if uci -s -N get "${__object_id:?}" >/dev/null 2>&1
+then
+	# Named section exists: ensure if --match applies to it
+	# if the "matched" option does not exist (e.g. empty section) we use the
+	# section unconditionally.
+	if match_value_is=$(uci -s -N get "${__object_id:?}.${match%%=*}" 2>/dev/null)
+	then
+		match_value_should=$(expr "${match}" : ".*='\\(.*\\)'$")
+
+		test "${match_value_is}" = "${match_value_should}" || {
+			printf 'Named section "%s" does not match --match "%s"\n' \
+				   "${__object_id:?}" "${match}" >&2
+			exit 1
+		}
+	fi
+
+	echo "${__object_id:?}"
+	exit 0
+fi
+
+# No correctly named section exists already: find one to which --match applies
+regex="^${package_filter}\\.@${section_filter}\\[[0-9]\\{1,\\}\\]\\.${match%%=*}="
+
+matched_sections=$(
+	uci -s -N -d "${RS}" show "${package_filter}" 2>/dev/null \
+	| grep -e "${regex}" \
+	| while read -r _line
+	  do
+		  if test "${_line#*=}" = "${match#*=}"
+		  then
+			  echo "${_line}"
+		  fi
+	  done \
+	| sed -e 's/\.[^.]*=.*$//')
+
+test "$(count_lines "${matched_sections}")" -le 1 || {
+	printf 'Found multiple matching sections:\n%s\n' "${matched_sections}" >&2
+	exit 1
+}
+
+echo "${matched_sections}"

cdist/conf/type/__uci_section/explorer/options

@@ -0,0 +1,48 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+# This explorer retrieves the current options of the configuration section.
+
+RS=$(printf '\036')
+
+section=$("${__type_explorer:?}/match")
+test -n "${section}" || exit 0
+
+uci -s -N -d "${RS}" show "${section}" 2>/dev/null \
+| awk -v VSEP="${RS}" '
+  {
+	  # Strip off the config and section parts
+	  is_opt = sub(/^([^.]*\.){2}/, "")
+
+	  if (!is_opt) {
+		  # this line represents the section -> skip
+		  next
+	  }
+
+	  if (index($0, VSEP)) {
+		  # Put values each on a line, like --option and --list parameters
+		  opt = substr($0, 1, index($0, "=") - 1)
+		  split(substr($0, length(opt) + 2), values, VSEP)
+		  for (i in values) {
+			  printf "%s=%s\n", opt, values[i]
+		  }
+	  } else {
+		  print
+	  }
+  }'

cdist/conf/type/__uci_section/explorer/type

@@ -0,0 +1,25 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+# This explorer retrieves the current section type.
+
+section=$("${__type_explorer:?}/match")
+test -n "${section}" || exit 0
+
+uci -s -N get "${section}" 2>/dev/null || true

cdist/conf/type/__uci_section/files/functions.sh

@@ -0,0 +1,59 @@
+# -*- mode: sh; indent-tabs-mode: t -*-
+
+NL=$(printf '\n '); NL=${NL% }
+
+grep_line() {
+	{ shift; printf '%s\n' "$@"; } | grep -qxF "$1"
+}
+
+print_errors() {
+	awk -v prefix="${1:-Found errors:}" -v suffix="${2-}" '
+		BEGIN {
+			if (getline) {
+				print prefix
+				print
+				rc = 1
+			}
+		}
+		{ print }
+		END {
+			if (rc && suffix) print suffix
+			exit rc
+		}' >&2
+}
+
+quote() {
+	for _arg
+	do
+		shift
+		if test -n "$(printf %s "${_arg}" | tr -d -c '\t\n \042-\047\050-\052\073-\077\133\\`|~' | tr -c '' '.')"
+		then
+			# needs quoting
+			set -- "$@" "$(printf "'%s'" "$(printf %s "${_arg}" | sed -e "s/'/'\\\\''/g")")"
+		else
+			set -- "$@" "${_arg}"
+		fi
+	done
+	unset _arg
+	printf '%s' "$*"
+}
+
+uci_cmd() {
+	# Usage: uci_cmd [UCI ARGUMENTS]...
+	mkdir -p "${__object:?}/files"
+	printf '%s\n' "$(quote "$@")" >>"${__object:?}/files/uci_batch.txt"
+}
+
+uci_validate_name() {
+	# like util.c uci_validate_name()
+	test -n "$*" && test -z "$(printf %s "$*" | tr -d '[:alnum:]_' | tr -c '' .)"
+}
+
+unquote_lines() {
+	sed -e '/^".*"$/{s/^"//;s/"$//}' \
+	    -e '/'"^'.*'"'$/{s/'"^'"'//;s/'"'$"'//}'
+}
+
+validate_options() {
+	grep -shv -e '^[[:alnum:]_]\{1,\}=' "$@"
+}

cdist/conf/type/__uci_section/files/option_state.awk

@@ -0,0 +1,91 @@
+# -*- mode: awk; indent-tabs-mode:t -*-
+# Usage: awk -f option_state.awk option_type option_name
+# e.g. awk -f option_state.awk option title
+#      awk -f option_state.awk list entry
+
+function unquote(s) {
+	# simplified dequoting of single quoted strings
+	if (s ~ /^'.*'$/) {
+		s = substr(s, 2, length(s) - 2)
+		sub(/'\\''/, "'", s)
+	}
+	return s
+}
+
+function valueof(line) {
+	if (line !~ /^[[:alpha:]_]+=/) return 0
+	return unquote(substr(line, index(line, "=") + 1))
+}
+
+BEGIN {
+	__object = ENVIRON["__object"]
+	if (!__object) exit 1
+
+	opttype = ARGV[1]
+	optname = ARGV[2]
+
+	if (opttype !~ /^(option|list)/ || !optname) {
+		print "invalid"
+		exit (e=1)
+	}
+
+	ARGV[1] = __object "/parameter/" opttype
+	ARGV[2] = __object "/explorer/options"
+
+	state = "present"
+}
+
+NR == FNR {
+	# memoize "should" state
+	if (index($0, optname "=") == 1) {
+		should[++should_count] = valueof($0)
+	}
+
+	# go to next line (important!)
+	next
+}
+
+{
+	# compare "is" state
+	if (index($0, optname "=") != 1)
+		next
+	++is_count
+
+	v = valueof($0)
+
+	if (v == should[is_count]) {
+		# looks good, but can't say definitely just from this line
+	} else if (is_count > should_count) {
+		# there are more "is" records than "should" -> definitely different
+		state = "different"
+		exit
+	} else {
+		# see if we can find the "is" value somewhere in "should"
+		for (i in should) {
+			if (v == should[i]) {
+				# value found -> could be rearranged
+				# FIXME: Duplicate values are not properly handled here. Do they matter?
+				state = "rearranged"
+				next
+			}
+		}
+
+		# "is" value could not be found in "should" -> definitely different
+		state = "different"
+		exit
+	}
+}
+
+END {
+	if (e) exit
+
+	if (!is_count) {
+		# no "is" values -> absent
+		state = "absent"
+	} else if (is_count < should_count) {
+		# "is" was shorter than "should" -> different
+		state = "different"
+	}
+
+	print state
+}

cdist/conf/type/__uci_section/files/uci_apply.sh

@@ -0,0 +1 @@
+../../__uci/files/uci_apply.sh

cdist/conf/type/__uci_section/gencode-remote

@@ -0,0 +1,174 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# shellcheck source=files/functions.sh
+. "${__type:?}/files/functions.sh"
+
+
+section=$(cat "${__object:?}/explorer/match")
+
+state_is=$(test -s "${__object:?}/explorer/type" && echo present || echo absent)
+state_should=$(cat "${__object:?}/parameter/state")
+
+case $state_should
+in
+	(present)
+		test -f "${__object:?}/parameter/type" || {
+			echo 'Parameter --type is required.' >&2
+			exit 1
+		}
+
+		type_is=$(cat "${__object:?}/explorer/type")
+		type_should=$(cat "${__object:?}/parameter/type")
+
+		if test -n "${type_is}"
+		then
+			sect_type=${type_is}
+		else
+			sect_type=${type_should##*.}
+		fi
+
+		if test -z "${section}"
+		then
+			# No section exists and --match was used.
+			# So we generate a new section identifier from $__object_id.
+			case ${__object_id:?}
+			in
+				(*.*) section=${__object_id:?} ;;
+				(*) section="${type_should%%.*}.${__object_id:?}" ;;
+			esac
+		fi
+
+		# Collect option names
+		if test -f "${__object:?}/parameter/list"
+		then
+			listnames_should=$(
+				sed -e 's/=.*$//' "${__object:?}/parameter/list" | sort -u)
+		fi
+
+		if test -f "${__object:?}/parameter/option"
+		then
+			optnames_should=$(
+				sed -e 's/=.*$//' "${__object:?}/parameter/option" | sort -u)
+		fi
+
+		# Make sure the section itself is present
+		if test "${state_is}" = absent \
+			|| test "${type_is}" != "${type_should#*.}"
+		then
+			printf 'set %s\n' "${section}" >>"${__messages_out:?}"
+			# shellcheck disable=SC2140
+			uci_cmd set "${section}"="${sect_type}"
+		fi
+
+		# Delete options/lists not in "should"
+		sed -e 's/=.*$//' "${__object:?}/explorer/options" \
+		| while read -r _optname
+		  do
+			  grep_line "${_optname}" "${listnames_should}" "${optnames_should}" || {
+				  printf 'delete %s\n' "${section}.${_optname}" >>"${__messages_out:?}"
+				  uci_cmd delete "${section}.${_optname}"
+			  } </dev/null
+		  done
+
+		opt_proc_error() {
+			printf 'An error occurred during processing of option %s\n' "${1:?}" >&2
+			exit 1
+		}
+
+		# Set "should" options
+		echo "${optnames_should}" \
+		| grep -e . \
+		| while read -r _optname
+		  do
+			  _opt_state=$(awk -f "${__type:?}/files/option_state.awk" option "${_optname}") \
+				  || opt_proc_error "${_optname}"
+			  case ${_opt_state}
+			  in
+				  (invalid)
+					  opt_proc_error "${_optname}"
+					  ;;
+				  (present)
+					  ;;
+				  (*)
+					  printf 'set %s\n' "${section}.${_optname}" >>"${__messages_out:?}"
+
+					  # shellcheck disable=SC2140
+					  uci_cmd set "${section}.${_optname}"="$(
+						  grep -e "^${_optname}=" "${__object:?}/parameter/option" \
+						  | sed -e 's/^.*=//' \
+						  | unquote_lines \
+						  | head -n 1)"
+					  ;;
+			  esac
+		  done
+
+		echo "${listnames_should}" \
+		| grep -e . \
+		| while read -r _optname
+		  do
+			  _list_state=$(awk -f "${__type:?}/files/option_state.awk" list "${_optname}") \
+				  || opt_proc_error "${_optname}"
+			  case ${_list_state}
+			  in
+				  (invalid)
+					  opt_proc_error "${_optname}"
+					  ;;
+				  (present)
+					  ;;
+				  (*)
+					  printf 'set_list %s\n' "${section}.${_optname}" >>"${__messages_out:?}"
+
+					  if test "${_list_state}" != absent
+					  then
+						  uci_cmd delete "${section}.${_optname}"
+					  fi
+
+					  grep "^${_optname}=" "${__object:?}/parameter/list" \
+					  | sed -e 's/^.*=//' \
+					  | unquote_lines \
+					  | while read -r _value
+					    do
+						    # shellcheck disable=SC2140
+						    uci_cmd add_list "${section}.${_optname}"="${_value}"
+					    done
+					  ;;
+			  esac
+		  done
+		;;
+	(absent)
+		if test "${state_is}" = absent
+		then
+			# if explorer found no section there is nothing to delete
+			exit 0
+		fi
+
+		printf 'delete %s\n' "${section}" >>"${__messages_out:?}"
+		uci_cmd delete "${section}"
+		;;
+esac
+
+if test -s "${__object:?}/files/uci_batch.txt"
+then
+	cat "${__type:?}/files/uci_apply.sh"
+	printf "uci_apply <<'EOF'\n"
+	cat "${__object:?}/files/uci_batch.txt"
+	printf '\nEOF\n'
+fi

cdist/conf/type/__uci_section/man.rst

@@ -0,0 +1,119 @@
+cdist-type__uci_section(7)
+==========================
+
+NAME
+----
+cdist-type__uci_section - Manage configuration sections in UCI
+
+
+DESCRIPTION
+-----------
+This cdist type can be used to replace whole configuration sections in OpenWrt's
+Unified Configuration Interface (UCI) system.
+It can be thought of as syntactic sugar for :strong:`cdist-type__uci`\ (7),
+as this type will generate the required `__uci` objects to make the section
+contain exactly the options specified using ``--option``.
+
+Since many default UCI sections are unnamed, this type allows to find the
+matching section by one of its options using the ``--match`` parameter.
+
+**NOTE:** Options already present on the target and not listed in ``--option``
+or ``--list`` will be deleted.
+
+
+REQUIRED PARAMETERS
+-------------------
+None.
+
+
+OPTIONAL PARAMETERS
+-------------------
+list
+    An option that is part of a list and should be present in the section (as
+    part of a list).  Lists with multiple options can be expressed by using the
+    same ``<option>`` repeatedly.
+
+    The value to this parameter is a ``<option>=<value>`` string.
+
+    ``<value>`` does not need special quoting for UCI.
+    The only requirement is that the value is passed to the type as a single
+    shell argument.
+match
+    Allows to find a section to "replace" through one of its parameters.
+
+    The value to this parameter is a ``<option>=<value>`` string.
+option
+    An option that should be present in the section.
+    This parameter can be used multiple times to specify multiple options.
+
+    The value to this parameter is a ``<option>=<value>`` string.
+
+    ``<value>`` does not need special quoting for UCI.
+    The only requirement is that the value is passed to the type as a single
+    shell argument.
+state
+    ``present`` or ``absent``, defaults to ``present``.
+type
+    The type of the section in the format: ``<config>.<section-type>``
+
+
+BOOLEAN PARAMETERS
+------------------
+None.
+
+
+EXAMPLES
+--------
+
+.. code-block:: sh
+
+    # Configure the dropbear daemon
+    __uci_section dropbear --type dropbear.dropbear \
+        --match Port=22 --option Port=22 \
+        --option PasswordAuth=off \
+        --option RootPasswordAuth=off
+
+    # Define a firewall zone comprised of lan and wlan networks
+    __uci_section firewall.internal --type firewall.zone \
+        --option name='internal' \
+        --list network='lan' \
+        --list network='wlan' \
+        --option input='ACCEPT' \
+        --option output='ACCEPT' \
+        --option forward='ACCEPT'
+
+    # Block SSH access from the guest network
+    __uci_section firewall.block_ssh_from_guest --type firewall.rule \
+        --option name='Block-SSH-Access-from-Guest' \
+        --option src='guest' \
+        --option proto='tcp' \
+        --option dest_port='22' \
+        --option target='REJECT'
+
+    # Configure a Wi-Fi access point
+    __uci_section wireless.default_radio0 --type wireless.wifi-iface \
+        --option device='radio0' \
+        --option mode='ap' \
+        --option network='wlan' \
+        --option ssid='mywifi' \
+        --option encryption="psk2' \
+        --option key='hunter2'
+
+
+SEE ALSO
+--------
+- https://openwrt.org/docs/guide-user/base-system/uci
+- :strong:`cdist-type__uci`\ (7)
+
+
+AUTHORS
+-------
+Dennis Camera <dennis.camera@ssrq-sds-fds.ch>
+
+
+COPYING
+-------
+Copyright \(C) 2020 Dennis Camera. 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.

cdist/conf/type/__uci_section/manifest

@@ -0,0 +1,88 @@
+#!/bin/sh -e
+#
+# 2020 Dennis Camera (dennis.camera@ssrq-sds-fds.ch)
+#
+# This file is part of cdist.
+#
+# cdist 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.
+#
+# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# shellcheck source=files/functions.sh
+. "${__type:?}/files/functions.sh"
+
+
+## Check section name and error if invalid!
+case ${__object_id:?}
+in
+	(*.*)
+		uci_validate_name "${__object_id%%.*}" || {
+			printf 'Invalid package name: %s\n' "${__object_id%%.*}" >&2
+			exit 1
+		}
+		uci_validate_name "${__object_id#*.}" || {
+			printf 'Invalid section name: %s\n' "${__object_id#*.}" >&2
+			exit 1
+		}
+		;;
+	(*)
+		uci_validate_name "${__object_id:?}" || {
+			printf 'Invalid section name: %s\n' "${__object_id:?}" >&2
+			exit 1
+		}
+		;;
+esac
+
+state_should=$(cat "${__object:?}/parameter/state")
+
+case $state_should
+in
+	(present)
+		test -f "${__object:?}/parameter/type" || {
+			echo 'Parameter --type is required.' >&2
+			exit 1
+		}
+		type_is=$(cat "${__object:?}/explorer/type")
+		type_should=$(cat "${__object:?}/parameter/type")
+
+		if test -n "${type_is}" && test "${type_is}" != "${type_should##*.}"
+		then
+			# Check if section type matches (section exists and --type provided)
+			printf 'Section type "%s" does not match --type "%s".\n' \
+				"${type_is}" "${type_should}" >&2
+			exit 1
+		fi
+
+		# Check options for syntax errors
+		validate_options "${__object:?}/parameter/list" "${__object:?}/parameter/object" \
+		| print_errors 'Found erroneous options in arguments:'
+
+		# Check for duplicate option names
+		if test -s "${__object:?}/parameter/option"
+		then
+			sed -e 's/=.*$//' "${__object:?}/parameter/option" \
+			| sort \
+			| uniq -d \
+			| print_errors \
+				  'Found duplicate --options:' \
+				  "$(printf '\nUse --list for lists, instead.')"
+		fi
+		;;
+	(absent)
+		:
+		;;
+	(*)
+		printf 'Invalid --state: %s\n' "${state_should}" >&2
+		exit 1
+		;;
+esac

cdist/conf/type/__uci_section/parameter/default/state

@@ -0,0 +1 @@
+present

cdist/conf/type/__uci_section/parameter/default/transaction

@@ -0,0 +1 @@
+default

cdist/conf/type/__uci_section/parameter/optional

@@ -0,0 +1,4 @@
+match
+state
+transaction
+type

cdist/conf/type/__uci_section/parameter/optional_multiple

@@ -0,0 +1,2 @@
+list
+option