Add __uci and __uci_commit types

cdist/conf/type/__uci/explorer/state

@@ -0,0 +1,89 @@
+#!/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 "${option}" 2>/dev/null) || {
+	echo absent
+	exit 0
+}
+
+# strip off trailing newline
+printf '%s' "${values_is}" \
+| awk '
+BEGIN {
+	state = "present"  # assume all is fine
+}
+NR == FNR {
+	# memoize "should" state
+	should[FNR] = $0
+
+	# go to next line (important!)
+	next
+}
+
+# compare "is" state
+$0 == should[FNR] { next }
+
+FNR > length(should) {
+	# 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 ($0 == should[i]) {
+			# ... value found -> rearranged
+			# FIXME: Duplicate values are not properly handled here. Do they matter?
+			state = "rearranged"
+			next
+		}
+	}
+
+	state = "different"
+	exit
+}
+
+END {
+	if (FNR < length(should)) {
+		# "is" was shorter than "should" -> different
+		state = "different"
+	}
+
+	print state
+}
+' "${__object:?}/parameter/value" RS="${RS}" -

cdist/conf/type/__uci/gencode-remote

@@ -0,0 +1,67 @@
+#!/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/>.
+#
+
+in_list() { printf '%s\n' "$@" | { grep -qxF "$(read -r NDL; echo "${NDL}")"; } }
+
+config=${__object_id:?}
+
+state_is=$(cat "${__object:?}/explorer/state")
+state_should=$(cat "${__object:?}/parameter/state")
+
+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
+
+		if test "$(wc -l "${__object:?}/parameter/value")" -gt 1
+		then
+			# "should" is a list
+			if test "${state_is}" != 'absent'
+			then
+				printf "uci delete '%s'\n" "${config}"
+			fi
+
+			while read -r value
+			do
+				printf "uci add_list '%s'='%s'\n" "${config}" "${value}"
+			done <"${__object:?}/parameter/value"
+		else
+			# "should" is a scalar
+			value=$(cat "${__object:?}/parameter/value")
+			printf "uci set '%s'='%s'\n" "${config}" "${value}"
+		fi
+		;;
+	(absent)
+		if in_list "${state_is}" 'absent'
+		then
+			exit 0
+		fi
+
+		printf "uci delete '%s'\n" "${config}"
+		;;
+	(*)
+		printf 'Invalid --state: %s\n' "${state_should}" >&2
+		exit 1
+		;;
+esac

cdist/conf/type/__uci/man.rst

@@ -0,0 +1,77 @@
+cdist-type__uci(7)
+==================
+
+NAME
+----
+cdist-type__uci - Manage configuration values in OpenWrt's
+Unified Configuration Interface (UCI)
+
+
+DESCRIPTION
+-----------
+This cdist type can be used to alter configuration options in OpenWrt's UCI
+system.
+
+Options can be applied in batches if the `--transaction` parameter is used.
+It is important to ensure that the `__uci_commit` object is executed before a
+new transaction is started.
+
+REQUIRED PARAMETERS
+-------------------
+value
+    The value to be set. Can be used multiple times.
+
+    Due to the way cdist handles arguments, values **must not** contain newline
+    characters.
+
+
+OPTIONAL PARAMETERS
+-------------------
+state
+    `present` or `absent`, defaults to `present`.
+transaction
+    The name of the transaction this option belongs to.
+    If none is given: "default" is used.
+
+
+BOOLEAN PARAMETERS
+------------------
+None.
+
+
+EXAMPLES
+--------
+
+.. code-block:: sh
+
+    # Set the system hostname
+    __uci system.@system[0].hostname --value 'OpenWrt'
+
+    # Enable NTP and NTPd (in one transaction)
+    __uci system.ntp.enabled --value 1 --transaction ntp
+    __uci system.ntp.enable_server --value 1 --transaction ntp
+    __uci system.ntp.server --transaction ntp \
+        --value '0.openwrt.pool.ntp.org' \
+        --value '1.openwrt.pool.ntp.org' \
+        --value '2.openwrt.pool.ntp.org' \
+        --value '3.openwrt.pool.ntp.org'
+    export require=__uci_commit/ntp
+
+
+SEE ALSO
+--------
+- https://openwrt.org/docs/guide-user/base-system/uci
+- :strong:`cdist-type__uci_commit`\ (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/manifest

@@ -0,0 +1,40 @@
+#!/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")
+
+transaction_name=$(cat "${__object:?}/parameter/transaction")
+
+case ${os}
+in
+	(openwrt)
+		# okay
+		;;
+	(*)
+		printf "Your operating system (%s) is currently not supported by this type (%s)\n" "${os}" "${__type##*/}" >&2
+		printf "Please contribute an implementation for it if you can.\n" >&2
+		exit 1
+		;;
+esac
+
+
+# Make sure the changes are being commited
+require=${__object_name:?} __uci_commit "${transaction_name}"

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

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

cdist/conf/type/__uci/parameter/default/transaction

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

cdist/conf/type/__uci/parameter/optional

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

cdist/conf/type/__uci/parameter/required_multiple

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

cdist/conf/type/__uci_commit/gencode-remote

@@ -0,0 +1,21 @@
+#!/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/>.
+#
+
+echo 'uci commit'

cdist/conf/type/__uci_commit/man.rst

@@ -0,0 +1,58 @@
+cdist-type__uci_commit(7)
+=========================
+
+NAME
+----
+cdist-type__uci_commit - Commit a UCI transaction.
+
+
+DESCRIPTION
+-----------
+This type executes the "uci commit" command on the target.
+It is usually not required to use this type. Use the `--transaction` parameter
+of `cdist-type__uci`\ (7) instead.
+
+
+REQUIRED PARAMETERS
+-------------------
+None.
+
+
+OPTIONAL PARAMETERS
+-------------------
+None.
+
+
+BOOLEAN PARAMETERS
+------------------
+None.
+
+
+EXAMPLES
+--------
+
+.. code-block:: sh
+
+    # Commit the default transaction
+    __uci_commit default
+
+    # Commit another transaction
+    __uci_commit my_transaction
+
+
+SEE ALSO
+--------
+: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.