stop clobbering company-backends

* using add-hook to modify company-backends is bad juju
* there does not appear to be a sensible way for a mode to
  modify company-backends either in the variable docstring or the
  online documentation here

https://company-mode.github.io/manual/Backends.html

  so... we should not modify it.
* document the added effort to use the company backend
* the only additional fanciness to `systemd-company-backend' is that
  it will automatically insert an = after completing a directive, so
  it might be nice to work that into the capf completion somehow and
  trash the company-specific code

Makefile

@@ -1,4 +1,8 @@
-SRC = systemd.el systemd-company.el
+SRC = systemd.el
+DATA = unit-directives.txt network-directives.txt nspawn-directives.txt
+DISTFILES := Makefile $(SRC) $(DATA) LICENSE README systemd-pkg.el test
+
+VERSION := $(shell awk '/^;; Version:/ {print $$3}' $(SRC))
 
 PREFIX = /usr/local
 datarootdir := $(PREFIX)/share
@@ -8,14 +12,32 @@ EMACS = emacs
 
 all: $(SRC:.el=.elc)
 
+systemd-pkg.el: $(SRC)
+	printf "(define-package \"systemd\" \"%s\" " $(VERSION) > $@
+	echo "\"Major mode for editing systemd units\")" >> $@
+
+systemd.elc: $(DATA)
+
+check: test/systemd-tests.el systemd.elc
+	@$(EMACS) -Q --batch -L . --eval "(progn \
+		(load-file \"test/systemd-tests.el\") \
+		(ert-run-tests-batch-and-exit))"
+
 clean:
-	$(RM) $(SRC:.el=.elc)
+	$(RM) $(SRC:.el=.elc) systemd-pkg.el
+
+dist: clean systemd-pkg.el
+	mkdir systemd-$(VERSION)
+	cp -r $(DISTFILES) systemd-$(VERSION)
+	tar cf systemd-$(VERSION).tar systemd-$(VERSION)
+	rm -rf systemd-$(VERSION)
 
 install:
 	install -d $(DESTDIR)$(emacsdir)/systemd
 	install -m644 $(SRC) $(SRC:.el=.elc) -t $(DESTDIR)$(emacsdir)/systemd
+	install -m644 $(DATA) -t $(DESTDIR)$(emacsdir)/systemd
 
 .el.elc:
 	$(EMACS) -L . --batch -f batch-byte-compile $<
 
-.PHONY: all clean install
+.PHONY: all check clean dist install

README

@@ -7,11 +7,11 @@ in `systemd.el`.
 Installation
 ------------
 
-Available as the `systemd' package on MELPA <http://melpa.org/>.
+Available as the `systemd` package on MELPA <https://melpa.org/>.
 
-In Emacs 25 or later, one can locally install as a package with
+In Emacs, one can locally install as a package with `make dist` and
 
-  M-x package-install-file RET /path/to/systemd-mode RET
+  M-x package-install-file RET /path/to/systemd-VERSION.tar RET
 
 Otherwise, for either installing into one's `load-path` or a system
 install, do the usual

network-directives.txt

@@ -0,0 +1,316 @@
+ARP
+ARPAllTargets
+ARPIPTargets
+ARPIntervalSec
+ARPValidate
+Activate
+ActiveSlave
+AdActorSystem
+AdActorSystemPriority
+AdSelect
+AdUserPortKey
+Address
+AddressAutoconfiguration
+Advertise
+AgeingTimeSec
+Alias
+AllMulticast
+AllSlavesActive
+AllowLocalRemote
+AllowPortToBeRoot
+AllowedIPs
+Anonymize
+Architecture
+AssignToLoopback
+AssociatedWith
+AutoJoin
+AutoNegotiation
+BSSID
+BindCarrier
+BitRate
+BitsPerSecond
+BlackList
+Bond
+Bridge
+Broadcast
+ClientIdentifier
+CombinedChannels
+ConfigureWithoutCarrier
+CopyDSCP
+Cost
+DHCP
+DHCPServer
+DNS
+DNSDefaultRoute
+DNSLifetimeSec
+DNSOverTLS
+DNSSEC
+DNSSECNegativeTrustAnchors
+DUIDRawData
+DUIDType
+DefaultLeaseTimeSec
+DefaultPVID
+DefaultRouteOnDevice
+Description
+Destination
+DestinationPort
+DiscoverPathMTU
+Domains
+DownDelaySec
+Driver
+Duplex
+DuplicateAddressDetection
+DynamicTransmitLoadBalancing
+ERSPANIndex
+EgressUntagged
+EmitDNS
+EmitDomains
+EmitLLDP
+EmitNTP
+EmitRouter
+EmitSIP
+EmitTimezone
+Encapsulation
+EncapsulationLimit
+EncapsulationType
+Encrypt
+Endpoint
+FDBAgeingSec
+FOUDestinationPort
+FOUSourcePort
+FailOverMACPolicy
+Family
+FastLeave
+FastOpenNoCookie
+FirewallMark
+Flags
+FlowLabel
+FooOverUDP
+ForceDHCPv6PDOtherInformation
+ForwardDelaySec
+From
+GVRP
+Gateway
+GatewayOnLink
+GenericProtocolExtension
+GenericReceiveOffload
+GenericSegmentationOffload
+GratuitousARP
+Group
+GroupForwardMask
+GroupPolicyExtension
+HairPin
+HelloTimeSec
+HomeAddress
+Host
+Hostname
+IAID
+IPDoNotFragment
+IPForward
+IPMasquerade
+IPProtocol
+IPServiceType
+IPVLAN
+IPv4LLRoute
+IPv4ProxyARP
+IPv6AcceptRA
+IPv6DuplicateAddressDetection
+IPv6FlowLabel
+IPv6HopLimit
+IPv6MTUBytes
+IPv6Preference
+IPv6PrefixDelegation
+IPv6PrivacyExtensions
+IPv6ProxyNDP
+IPv6ProxyNDPAddress
+IPv6RapidDeploymentPrefix
+IPv6Token
+ISATAP
+Id
+IgnoreCarrierLoss
+IncomingInterface
+Independent
+InitialAdvertisedReceiveWindow
+InitialCongestionWindow
+InputKey
+InterfaceId
+InvertRule
+KeepConfiguration
+KernelCommandLine
+KernelVersion
+Key
+KeyFile
+KeyId
+Kind
+L2MissNotification
+L3MissNotification
+LACPTransmitRate
+LLDP
+LLMNR
+Label
+LargeReceiveOffload
+Layer2SpecificHeader
+LearnPacketIntervalSec
+Learning
+LifetimeSec
+LinkLayerAddress
+LinkLocalAddressing
+ListenPort
+Local
+LooseBinding
+MACAddress
+MACAddressPolicy
+MACVLAN
+MACsec
+MIIMonitorSec
+MTUBytes
+MVRP
+MacLearning
+ManageTemporaryAddress
+Managed
+MaxAgeSec
+MaxAttempts
+MaxLeaseTimeSec
+MaximumFDBEntries
+Metric
+MinLinks
+Mode
+MultiQueue
+Multicast
+MulticastDNS
+MulticastFlood
+MulticastIGMPVersion
+MulticastQuerier
+MulticastRouter
+MulticastSnooping
+MulticastToUnicast
+NTP
+Name
+NamePolicy
+NeighborSuppression
+NetworkEmulatorDelayJitterSec
+NetworkEmulatorDelaySec
+NetworkEmulatorDuplicateRate
+NetworkEmulatorLossRate
+NetworkEmulatorPacketLimit
+OnLink
+OriginalName
+OtherChannels
+OtherInformation
+OutgoingInterface
+OutputKey
+PVID
+PacketInfo
+PacketNumber
+PacketsPerSlave
+Parent
+Path
+Peer
+PeerPort
+PeerSessionId
+PeerTunnelId
+PersistentKeepalive
+PoolOffset
+PoolSize
+Port
+PortRange
+PreferredLifetime
+PreferredLifetimeSec
+PreferredSource
+Prefix
+PrefixDelegationHint
+PrefixRoute
+PresharedKey
+PresharedKeyFile
+PrimaryReselectPolicy
+PrimarySlave
+Priority
+PrivateKey
+PrivateKeyFile
+Property
+Protocol
+ProxyARP
+ProxyARPWiFi
+PublicKey
+QuickAck
+RapidCommit
+ReduceARPProxy
+Remote
+RemoteChecksumRx
+RemoteChecksumTx
+ReorderHeader
+RequestBroadcast
+RequestOptions
+RequiredForOnline
+ResendIGMP
+RestartSec
+Route
+RouteMetric
+RouteShortCircuit
+RouteTable
+RouterLifetimeSec
+RouterPreference
+RoutesToDNS
+RxBufferSize
+RxChannels
+SSID
+STP
+SamplePoint
+Scope
+SendHostname
+SendOption
+SendRelease
+SerializeTunneledPackets
+SessionId
+Source
+SourcePort
+TCP6SegmentationOffload
+TCPSegmentationOffload
+TOS
+TTL
+TTLPropagate
+Table
+Timezone
+To
+TransmitHashPolicy
+TripleSampling
+Tunnel
+TunnelId
+TxBufferSize
+TxChannels
+Type
+TypeOfService
+UDP6ZeroChecksumRx
+UDP6ZeroChecksumTx
+UDPChecksum
+UDPSourcePort
+UnicastFlood
+Unmanaged
+UpDelaySec
+UseAutonomousPrefix
+UseBPDU
+UseDNS
+UseDomains
+UseForEncoding
+UseHostname
+UseMTU
+UseNTP
+UseOnLinkPrefix
+UseRoutes
+UseSIP
+UseTimezone
+User
+UserClass
+VLAN
+VLANFiltering
+VLANId
+VNI
+VNetHeader
+VRF
+VXLAN
+ValidLifetimeSec
+VendorClassIdentifier
+Virtualization
+WLANInterfaceType
+WakeOnLan
+Xfrm

nspawn-directives.txt

@@ -0,0 +1,38 @@
+Boot
+Ephemeral
+ProcessTwo
+Parameters
+Environment
+User
+WorkingDirectory
+PivotRoot
+Capability
+NoNewPrivileges
+KillSignal
+Personality
+MachineID
+PrivateUsers
+NotifyReady
+SystemCallFilter
+LimitCPU
+OOMScoreAdjust
+CPUAffinity
+Hostname
+ResolvConf
+Timezone
+LinkJournal
+ReadOnly
+Volatile
+Bind
+TemporaryFileSystem
+Inaccessible
+Overlay
+PrivateUsersChown
+Private
+VirtualEthernet
+VirtualEthernetExtra
+Interface
+MACVLAN
+Bridge
+Zone
+Port

systemd-company.el

@@ -1,131 +0,0 @@
-;;; systemd-company.el --- company backend for systemd unit directives -*- lexical-binding: t -*-
-
-;; Copyright (C) 2015  Mark Oteiza <mvoteiza@udel.edu>
-
-;; Author: Mark Oteiza <mvoteiza@udel.edu>
-
-;; 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/>.
-
-;;; Commentary:
-
-;;; Code:
-
-(require 'cl-lib)
-
-(declare-function company-mode "company")
-(declare-function company-begin-backend "company")
-(declare-function company-grab-symbol "company")
-
-(defconst systemd-company-directives
-  ;; TODO: keep a script of sorts for generating this list.  systemd
-  ;; source has a python script in tools/ for parsing the
-  ;; documentation xml for the unit directives.
-  ;;
-  ;; forcer on freenode threw together a curl monstrosity for achieving
-  ;; the same:
-  ;; curl -s http://www.freedesktop.org/software/systemd/man/systemd.directives.html | tr -d '\n' | sed 's/>/>\n/g' | sed -ne '/Unit directives/,/Options on the kernel/p' | sed -ne 's/.*<dt id="\([^-][^"]*\)=">.*/\1/p'
-  ;; Quote, wrap with fill-column at 72, insert into list and indent
-  '("Accept" "AccuracySec" "After" "Alias" "AllowIsolate" "Also"
-    "AppArmorProfile" "AssertACPower" "AssertArchitecture"
-    "AssertCapability" "AssertDirectoryNotEmpty" "AssertFileIsExecutable"
-    "AssertFileNotEmpty" "AssertFirstBoot" "AssertHost"
-    "AssertKernelCommandLine" "AssertNeedsUpdate" "AssertPathExists"
-    "AssertPathExistsGlob" "AssertPathIsDirectory" "AssertPathIsMountPoint"
-    "AssertPathIsReadWrite" "AssertPathIsSymbolicLink" "AssertSecurity"
-    "AssertVirtualization" "Backlog" "Before" "BindIPv6Only" "BindToDevice"
-    "BindsTo" "BlockIOAccounting" "BlockIODeviceWeight"
-    "BlockIOReadBandwidth" "BlockIOWeight" "BlockIOWriteBandwidth"
-    "Broadcast" "BusName" "BusPolicy" "CPUAccounting" "CPUAffinity"
-    "CPUQuota" "CPUSchedulingPolicy" "CPUSchedulingPriority"
-    "CPUSchedulingResetOnFork" "CPUShares" "Capabilities"
-    "CapabilityBoundingSet" "ConditionACPower" "ConditionArchitecture"
-    "ConditionCapability" "ConditionDirectoryNotEmpty"
-    "ConditionFileIsExecutable" "ConditionFileNotEmpty" "ConditionFirstBoot"
-    "ConditionHost" "ConditionKernelCommandLine" "ConditionNeedsUpdate"
-    "ConditionPathExists" "ConditionPathExistsGlob"
-    "ConditionPathIsDirectory" "ConditionPathIsMountPoint"
-    "ConditionPathIsReadWrite" "ConditionPathIsSymbolicLink"
-    "ConditionSecurity" "ConditionVirtualization" "Conflicts"
-    "DefaultDependencies" "DefaultInstance" "DeferAcceptSec" "Delegate"
-    "Description" "DeviceAllow" "DevicePolicy" "DirectoryMode"
-    "DirectoryNotEmpty" "Documentation" "Environment" "EnvironmentFile"
-    "ExecReload" "ExecStart" "ExecStartPost" "ExecStartPre" "ExecStop"
-    "ExecStopPost" "ExecStopPre" "FailureAction" "FileDescriptorStoreMax"
-    "FreeBind" "Group" "GuessMainPID" "IOSchedulingClass"
-    "IOSchedulingPriority" "IPTOS" "IPTTL" "IgnoreOnIsolate"
-    "IgnoreOnSnapshot" "IgnoreSIGPIPE" "InaccessibleDirectories"
-    "JobTimeoutAction" "JobTimeoutRebootArgument" "JobTimeoutSec"
-    "JoinsNamespaceOf" "KeepAlive" "KeepAliveIntervalSec" "KeepAliveProbes"
-    "KeepAliveTimeSec" "KillMode" "KillSignal" "LimitAS" "LimitCORE"
-    "LimitCPU" "LimitDATA" "LimitFSIZE" "LimitLOCKS" "LimitMEMLOCK"
-    "LimitMSGQUEUE" "LimitNICE" "LimitNOFILE" "LimitNPROC" "LimitRSS"
-    "LimitRTPRIO" "LimitRTTIME" "LimitSIGPENDING" "LimitSTACK"
-    "ListenDatagram" "ListenFIFO" "ListenMessageQueue" "ListenNetlink"
-    "ListenSequentialPacket" "ListenSpecial" "ListenStream" "MakeDirectory"
-    "Mark" "MaxConnections" "MemoryAccounting" "MemoryLimit"
-    "MessageQueueMaxMessages" "MessageQueueMessageSize" "MountFlags" "Nice"
-    "NoDelay" "NoNewPrivileges" "NonBlocking" "NotifyAccess"
-    "OOMScoreAdjust" "OnActiveSec" "OnBootSec" "OnCalendar" "OnFailure"
-    "OnFailureJobMode" "OnStartupSec" "OnUnitActiveSec" "OnUnitInactiveSec"
-    "Options" "PAMName" "PIDFile" "PartOf" "PassCredentials" "PassSecurity"
-    "PathChanged" "PathExists" "PathExistsGlob" "PathModified"
-    "PermissionsStartOnly" "Persistent" "Personality" "PipeSize" "Priority"
-    "PrivateDevices" "PrivateNetwork" "PrivateTmp" "PropagatesReloadTo"
-    "ProtectHome" "ProtectSystem" "ReadOnlyDirectories"
-    "ReadWriteDirectories" "RebootArgument" "ReceiveBuffer"
-    "RefuseManualStart" "RefuseManualStop" "ReloadPropagatedFrom"
-    "RemainAfterExit" "RemoveOnStop" "RequiredBy" "Requires"
-    "RequiresMountsFor" "RequiresOverridable" "Requisite"
-    "RequisiteOverridable" "Restart" "RestartForceExitStatus"
-    "RestartPreventExitStatus" "RestartSec" "RestrictAddressFamilies"
-    "ReusePort" "RootDirectory" "RootDirectoryStartOnly" "RuntimeDirectory"
-    "RuntimeDirectoryMode" "SELinuxContext" "SELinuxContextFromNet"
-    "SecureBits" "SendBuffer" "SendSIGHUP" "SendSIGKILL" "Service" "Slice"
-    "SloppyOptions" "SmackLabel" "SmackLabelIPIn" "SmackLabelIPOut"
-    "SmackProcessLabel" "SocketGroup" "SocketMode" "SocketUser" "Sockets"
-    "SourcePath" "StandardError" "StandardInput" "StandardOutput"
-    "StartLimitAction" "StartLimitBurst" "StartLimitInterval"
-    "StartupBlockIOWeight" "StartupCPUShares" "StopWhenUnneeded"
-    "SuccessExitStatus" "SupplementaryGroups" "Symlinks" "SyslogFacility"
-    "SyslogIdentifier" "SyslogLevel" "SyslogLevelPrefix"
-    "SystemCallArchitectures" "SystemCallErrorNumber" "SystemCallFilter"
-    "TCPCongestion" "TTYPath" "TTYReset" "TTYVHangup" "TTYVTDisallocate"
-    "TimeoutIdleSec" "TimeoutSec" "TimeoutStartSec" "TimeoutStopSec"
-    "TimerSlackNSec" "Transparent" "Type" "UMask" "Unit" "User"
-    "UtmpIdentifier" "WakeSystem" "WantedBy" "Wants" "WatchdogSec" "What"
-    "Where" "WorkingDirectory")
-  "Configuration directives for systemd 220.")
-
-(defun systemd-company--setup (enable)
-  (when (fboundp 'systemd-company--setup-company)
-    (systemd-company--setup-company enable)))
-
-(with-eval-after-load "company"
-  (defun systemd-company-backend (command &optional arg &rest ignored)
-    (interactive (list 'interactive))
-    (cl-case command
-      (interactive (company-begin-backend 'systemd-company-backend))
-      (prefix (and (eq major-mode 'systemd-mode)
-                   (company-grab-symbol)))
-      (candidates
-       (cl-remove-if-not (lambda (c) (string-prefix-p arg c))
-                         systemd-company-directives))))
-  (defun systemd-company--setup-company (enable)
-    (when enable
-      (add-to-list (make-local-variable 'company-backends) 'systemd-company-backend))
-    (company-mode (if enable 1 -1))))
-
-(provide 'systemd-company)
-
-;;; systemd-company.el ends here

systemd.el

@@ -1,9 +1,9 @@
 ;;; systemd.el --- Major mode for editing systemd units -*- lexical-binding: t -*-
 
-;; Copyright (C) 2014-2015  Mark Oteiza <mvoteiza@udel.edu>
+;; Copyright (C) 2014-2023  Mark Oteiza <mvoteiza@udel.edu>
 
 ;; Author: Mark Oteiza <mvoteiza@udel.edu>
-;; Version: 1.2.1
+;; Version: 1.6.1
 ;; Package-Requires: ((emacs "24.4"))
 ;; Keywords: tools, unix
 
@@ -24,24 +24,33 @@
 
 ;; Major mode for editing systemd units.
 
-;; Reflects a stripped down conf-mode, except with strict regex for
-;; whitespace, and highlighting for special syntax, such as specifiers
-;; and booleans.  Features a facility for browsing documentation: use
-;; C-c C-o to open links to documentation in a unit (cf. systemctl
-;; help).
+;; Similar to `conf-mode' but with enhanced highlighting; e.g. for
+;; specifiers and booleans.  Employs strict regex for whitespace.
+;; Features a facility for browsing documentation: use C-c C-o to open
+;; links to documentation in a unit (cf. systemctl help).
 
-;; Supports completion of unit directives via `company-mode'.
+;; Supports completion of directives and sections in either units or
+;; network configuration.  Both a completer for
+;; `completion-at-point-functions' and a company backend are provided.
+;; The latter can be enabled by adding `company-mode' to
+;; `systemd-mode-hook' and adding `systemd-company-backend' to
+;; `company-backends'.
 
 ;;; Code:
 
+(require 'conf-mode)
 (require 'thingatpt)
 (require 'url-parse)
 
-(require 'systemd-company)
+(declare-function company-begin-backend "company")
+(declare-function company-grab-symbol "company")
+
+(defvar font-lock-beg)
+(defvar font-lock-end)
 
 (defgroup systemd ()
   "Major mode for editing systemd units."
-  :link '(url-link "http://www.freedesktop.org/wiki/Software/systemd/")
+  :link '(url-link "https://www.freedesktop.org/wiki/Software/systemd/")
   :group 'tools)
 
 (defcustom systemd-browse-url-function 'browse-url
@@ -65,46 +74,96 @@
                 (function :tag "Other function"))
   :group 'systemd)
 
-(defcustom systemd-use-company-p t
-  "Whether to use `company-mode' for completion, if available."
-  :type 'boolean
+(defcustom systemd-mode-hook nil
+  "Hook run after entering `systemd-mode'."
+  :type 'hook
+  :options '(company-mode flycheck-mode)
   :group 'systemd)
 
-(defvar systemd-font-lock-keywords
-  `(("^\\([#;]\\)\\(.*\\)$"
-     (1 'font-lock-comment-delimiter-face)
-     (2 'font-lock-comment-face))
-    ("\\\\$" 0 'font-lock-warning-face) ; line break
-    ;; sections
-    ("^\\(\\[[[:upper:]][[:alnum:]]+\\]\\)"
-     1 'font-lock-type-face)
-    ;; keys
-    ("^\\([[:upper:]][[:alnum:]]+\\)="
-     1 'font-lock-keyword-face)
-    ;; boolean arguments
-    ("=\\(1\\|yes\\|true\\|on\\|0\\|no\\|false\\|off\\)$"
-     1 'font-lock-constant-face)
-    ;; specifiers
-    ("%[nNpPiIfcrRtuUhsmbHv%]" 0 'font-lock-constant-face))
-  "Default expressions to highlight in `systemd-mode'. See systemd.unit(5)
-for details on unit file syntax.")
+(defconst systemd-unit-sections
+  '("Unit" "Install" "Service")
+  "Configuration sections for systemd 244.")
+
+(defconst systemd-unit-directives
+  (eval-when-compile
+    (with-temp-buffer
+      (insert-file-contents
+       (let ((f "unit-directives.txt"))
+         (if (null load-file-name) f
+           (expand-file-name f (file-name-directory load-file-name)))))
+      (split-string (buffer-string))))
+  "Configuration directives for systemd.")
+
+(defconst systemd-network-sections
+  '("Match" "Link" "NetDev" "VLAN" "MACVLAN" "MACVTAP" "IPVLAN" "IPVTAP" "VXLAN"
+    "GENEVE" "L2TP" "L2TPsession" "MACsec" "FooOverUDP"
+    "Tunnel" "Peer" "Tun" "Tap" "Bond" "Network" "Address" "Route" "DHCP"
+    "Neighbor" "IPv6AddressLabel" "RoutingPolicyRule" "NextHop" "DHCPv4"
+    "DHCPv6" "IPv6AcceptRA" "DHCPServer" "IPv6Prefix" "CAN" 
+    "Bridge" "BridgeFDB" "BridgeVLAN" "VXCAN" "WireGuard" "WireGuardPeer")
+  "Network configuration sections for systemd 244 (not exhaustive).")
+
+(defconst systemd-network-directives
+  (eval-when-compile
+    (with-temp-buffer
+      (insert-file-contents
+       (let ((f "network-directives.txt"))
+         (if (null load-file-name) f
+           (expand-file-name f (file-name-directory load-file-name)))))
+      (split-string (buffer-string))))
+  "Network configuration directives for systemd.")
+
+(defconst systemd-nspawn-sections
+  '("Exec" "Files" "Network")
+  "Namespace container configuration sections for systemd 244.")
+
+(defconst systemd-nspawn-directives
+  (eval-when-compile
+    (with-temp-buffer
+      (insert-file-contents
+       (let ((f "nspawn-directives.txt"))
+         (if (null load-file-name) f
+           (expand-file-name f (file-name-directory load-file-name)))))
+      (split-string (buffer-string))))
+  "Namespace container configuration directives for systemd.")
+
+;;;###autoload
+(defconst systemd-autoload-regexp
+  (rx (+? (any "a-zA-Z0-9-_.@\\")) "."
+      (or "automount" "busname" "mount" "service" "slice"
+          "socket" "swap" "target" "timer" "link" "netdev" "network")
+      string-end)
+  "Regexp for file buffers in which to autoload `systemd-mode'.")
+
+;;;###autoload
+(defconst systemd-tempfn-autoload-regexp
+  (rx ".#"
+      (or (and (+? (any "a-zA-Z0-9-_.@\\")) "."
+               (or "automount" "busname" "mount" "service" "slice"
+                   "socket" "swap" "target" "timer" "link" "netdev" "network"))
+          "override.conf")
+      (= 16 (char hex-digit)) string-end)
+  "Regexp for temp file buffers in which to autoload `systemd-mode'.")
+
+;;;###autoload
+(defconst systemd-dropin-autoload-regexp
+  (rx "/systemd/" (+? anything) ".d/" (+? (not (any ?/))) ".conf" string-end)
+  "Regexp for dropin config file buffers in which to autoload `systemd-mode'.")
 
 (defun systemd-get-value (start)
-  "Joins lines in the key value starting at buffer position START,
-possibly broken by a backslash, and returns a string containing
-the value."
-  (let ((break "\\\\\n")
-        end)
+  "Return the value of the key whose value begins at position START.
+Lines ending in a backslash are concatenated with the next
+according to systemd.unit(5)."
+  (let (end)
     (save-excursion
-      (while (progn (goto-char (1- (line-end-position)))
-                    (looking-at break))
+      (while (= (char-before (line-end-position)) ?\\)
         (forward-line))
       (setq end (line-end-position))
-      (replace-regexp-in-string break " " (buffer-substring start end)))))
+      (replace-regexp-in-string "\\\\\n" " " (buffer-substring start end)))))
 
 (defun systemd-doc-find ()
-  "Find the value of the unit's “Documentation” keys and return
-as a list of strings, otherwise nil."
+  "Find the value of the unit's “Documentation” keys.
+Return values in a list of strings, otherwise nil."
   (let ((key "^Documentation=")
         string)
     (save-excursion
@@ -115,15 +174,16 @@ as a list of strings, otherwise nil."
       (remove "\\" (split-string string)))))
 
 (defun systemd-doc-man (page)
-  "Open a manual page with `systemd-man-function'."
+  "Open a manual page PAGE with `systemd-man-function'."
   (pcase (symbol-name systemd-man-function)
     ("woman" (woman (replace-regexp-in-string "([[:alnum:]]+)" "" page)))
     ("man" (man page))
     (_ (apply 'systemd-man-function page))))
 
 (defun systemd-doc-open (url)
-  "Open URL.  Interactively completes the documentation in the
-current unit file, defaulting to the link under point, if any."
+  "Prompt to open URL.
+Interactively completes the documentation in the current unit
+file, defaulting to the link under point, if any."
   (interactive
    (let* ((completion-cycle-threshold t)
           (collection (systemd-doc-find))
@@ -142,15 +202,174 @@ current unit file, defaulting to the link under point, if any."
       (_ (user-error "Invalid link")))))
 
 (defun systemd-doc-directives ()
-  "Open systemd.directives(7)"
+  "Open systemd.directives(7)."
   (interactive)
   (systemd-doc-man "systemd.directives(7)"))
 
+(defun systemd-buffer-section-p ()
+  "Return t if current line begins with \"[\", otherwise nil."
+  (= (char-after (line-beginning-position)) ?\[))
+
+(defun systemd-file-network-p (filename)
+  "Return non-nil if FILENAME has a network-type extension, otherwise nil."
+  (string-match-p (rx "." (or "link" "netdev" "network") string-end)
+                  filename))
+
+(defun systemd-file-nspawn-p (filename)
+  "Return non-nil if FILENAME has an nspawn extension, otherwise nil."
+  (string-match-p (rx ".nspawn" string-end) filename))
+
+(defun systemd-completion-table (&rest _ignore)
+  "Return a list of completion candidates."
+  (let ((sectionp (systemd-buffer-section-p))
+        (name (buffer-name)))
+    (cond
+     ((systemd-file-nspawn-p name)
+      (if sectionp systemd-nspawn-sections systemd-nspawn-directives))
+     ((systemd-file-network-p name)
+      (if sectionp systemd-network-sections systemd-network-directives))
+     (t (if sectionp systemd-unit-sections systemd-unit-directives)))))
+
+(defun systemd-complete-at-point ()
+  "Complete the symbol at point."
+  (let ((bounds (bounds-of-thing-at-point 'symbol)))
+    (list (or (car bounds) (point))
+          (or (cdr bounds) (point))
+          (completion-table-dynamic #'systemd-completion-table))))
+
+(defun systemd-company-backend (command &optional arg &rest _ignored)
+  "Backend for `company-mode' in `systemd-mode' buffers."
+  (interactive (list 'interactive))
+  (pcase command
+    (`interactive (company-begin-backend 'systemd-company-backend))
+    (`prefix (and (eq major-mode 'systemd-mode) (company-grab-symbol)))
+    (`candidates (all-completions arg (systemd-completion-table nil)))
+    (`post-completion (if (not (systemd-buffer-section-p)) (insert "=")))))
+
+(defun systemd-construct-start-p ()
+  "Return non-nil if the current line is the first in a multi-line construct."
+  (let ((flag t))
+    (save-excursion
+      (while (and (zerop (forward-line -1))
+                  (eq ?\\ (char-before (line-end-position)))
+                  (skip-chars-forward " \t")
+                  (setq flag (memq (following-char) '(?# ?\;))))))
+    flag))
+
+(defun systemd-syntax-propertize (start end)
+  "`systemd-propertize-function' for `systemd-mode' buffers."
+  (let ((case-fold-search nil))
+    (goto-char start)
+    (funcall
+     (syntax-propertize-rules
+      ("^[ \t]*\\([;#]\\)$?"
+       (1 (when (systemd-construct-start-p) (string-to-syntax "<")))))
+     start end)))
+
+(defun systemd-value-extend-region ()
+  "Return the EOL position of the last line of the construct at point."
+  (while (and (= (char-before (line-end-position)) ?\\)
+              (skip-chars-forward " \t")
+              (not (memq (following-char) '(?# ?\;)))
+              (zerop (forward-line))))
+  (line-end-position))
+
+(defun systemd-font-lock-extend-region ()
+  (goto-char font-lock-beg)
+  (while (and (zerop (forward-line -1))
+              (= (char-before (line-end-position)) ?\\)
+              (skip-chars-forward " \t")
+              (not (memq (following-char) '(?# ?\;)))))
+  (setq font-lock-beg (point-marker))
+  (goto-char font-lock-end)
+  (setq font-lock-end (systemd-value-extend-region)))
+
+(defmacro define-systemd-matcher (name regexp &optional docstring)
+  "Define a new function NAME that matches REGEXP in a multi-line construct.
+Only returns matches of REGEXP on lines passing `systemd-construct-start-p'."
+  (declare (debug (symbolp stringp &optional stringp))
+           (indent 2) (doc-string 3))
+  `(defun ,name (limit)
+     ,docstring
+     (let (match)
+       (while (and (setq match (re-search-forward ,regexp limit t))
+                   (not (systemd-construct-start-p))))
+       match)))
+
+(define-systemd-matcher systemd-section-matcher
+    "^\\(\\[\\([[:upper:]][[:alnum:]]+\\|X-.*?\\)\\]\\)"
+  "Matcher for section titles.")
+
+(define-systemd-matcher systemd-key-matcher "^\\([[:upper:]][[:alnum:]]+\\)="
+  "Matcher for keys (unit directives).")
+
+(defun systemd-exec-prefix-anchored-matcher (limit)
+  "Matcher for the exec prefix in anchored font-lock rule.
+See `font-lock-keywords' and (info \"(elisp) Search-based Fontification\")."
+  (let ((pos (car (match-data)))
+        (prefixes '(?- ?@ ?+))
+        char end res)
+    (while (and (memq (setq char (following-char)) prefixes)
+                (< (point) limit))
+      (forward-char)
+      (setq prefixes (remq char prefixes))
+      (setq end (point-marker)))
+    (when end
+      (prog1 (setq res (list (1+ pos) end))
+        (set-match-data res)))))
+
+(defconst systemd-font-lock-keywords-1
+  '((systemd-section-matcher 1 'font-lock-type-face)
+    (systemd-key-matcher 1 'font-lock-keyword-face))
+  "Minimal expressions to highlight in `systemd-mode'.")
+
+(defconst systemd-font-lock-keywords-2
+  `(,@systemd-font-lock-keywords-1
+    ("\\\\$" 0 'font-lock-warning-face) ; line break
+    ;; boolean arguments
+    (,(rx "=" (group (or "yes" "true" "on" "0" "no" "false" "off")) eol)
+     1 'font-lock-constant-face)
+    ("="
+     ;; exec prefixes
+     (systemd-exec-prefix-anchored-matcher
+      nil nil (0 'font-lock-negation-char-face))
+     ;; environment variables
+     ("\\$[A-Z_]+\\>"
+      (systemd-value-extend-region) nil (0 'font-lock-variable-name-face))
+     ;; specifiers
+     ("%[abBCEfgGhHiIjJlLmnNopPrRsStTuUvVw%]"
+      (systemd-value-extend-region) nil (0 'font-lock-constant-face))))
+  "Extended expressions to highlight in `systemd-mode'.")
+
+(defconst systemd-font-lock-keywords-3
+  `(,@systemd-font-lock-keywords-2
+    ("^Type=\\(simple\\|forking\\|oneshot\\|dbus\\|notify\\|idle\\)$"
+     1 'font-lock-builtin-face)
+    (,(rx bol "Restart="
+          (group (or "no" "on-success" "on-failure"
+                     "on-abnormal" "on-watchdog" "on-abort" "always"))
+          eol)
+     1 'font-lock-builtin-face)
+    ("^KillMode=\\(control-group\\|process\\|mixed\\|none\\)$"
+     1 'font-lock-builtin-face)
+    (,(rx bol "KillSignal="
+          (group
+           (or "SIGHUP" "SIGINT" "SIGQUIT" "SIGILL" "SIGABRT" "SIGFPE" "SIGKILL"
+               "SIGSEGV" "SIGPIPE" "SIGALRM" "SIGTERM" "SIGUSR1" "SIGUSR2"
+               "SIGCHLD" "SIGCONT" "SIGSTOP" "SIGTSTP" "SIGTTIN" "SIGTTOU"))
+          eol)
+     1 'font-lock-constant-face))
+  "Flamboyant expressions to highlight in `systemd-mode'.")
+
+(defvar systemd-font-lock-keywords 'systemd-font-lock-keywords-2
+  "Default expressions to highlight in `systemd-mode'.
+See systemd.unit(5) for details on unit file syntax.")
+
 (defvar systemd-mode-syntax-table
   (let ((table (make-syntax-table)))
-    (modify-syntax-entry ?\" "." table)
-    (modify-syntax-entry ?\n ">" table)
-    (modify-syntax-entry ?\% "\\" table)
+    (modify-syntax-entry ?% "/" table)
+    (modify-syntax-entry ?$ "'" table)
+    (modify-syntax-entry ?\; "." table)
     table)
   "Syntax table used in `systemd-mode' buffers.")
 
@@ -161,31 +380,42 @@ current unit file, defaulting to the link under point, if any."
     map)
   "Keymap used in `systemd-mode' buffers.")
 
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.automount\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.busname\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.mount\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.service\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.slice\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.socket\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.target\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.timer\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.link\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.netdev\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.network\\'" . systemd-mode))
-;;;###autoload (add-to-list 'auto-mode-alist '("\\.override\\.conf.*\\'" . systemd-mode))
+(easy-menu-define systemd-mode-menu systemd-mode-map
+  "Menu used in `systemd-mode' buffers."
+  '("Systemd"
+    ["Open Unit File help" systemd-doc-open
+     :help "Documentation referenced in current buffer"]
+    ["Open systemd.directives(7)" systemd-doc-directives
+     :help "Index of configuration directives"]))
+
+;;;###autoload (add-to-list 'auto-mode-alist '("\\.nspawn\\'" . systemd-mode))
+;;;###autoload (add-to-list 'auto-mode-alist `(,systemd-autoload-regexp . systemd-mode))
+;;;###autoload (add-to-list 'auto-mode-alist `(,systemd-tempfn-autoload-regexp . systemd-mode))
+;;;###autoload (add-to-list 'auto-mode-alist `(,systemd-dropin-autoload-regexp . systemd-mode))
 
 ;;;###autoload
-(define-derived-mode systemd-mode fundamental-mode "Systemd"
-  "Major mode for editing systemd unit files. See
-http://www.freedesktop.org/wiki/Software/systemd/ for more
-information about systemd.  The hook `systemd-mode-hook' is run
-at mode initialization.
+(define-derived-mode systemd-mode conf-mode "Systemd"
+  "Major mode for editing systemd unit files.
+See https://www.freedesktop.org/wiki/Software/systemd/ for more
+information about systemd.
+
+In addition to any hooks its parent mode might have run, this
+mode runs the hook `systemd-mode-hook' at mode initialization.
 
 Key bindings:
 \\{systemd-mode-map}"
-  (systemd-company--setup systemd-use-company-p)
-  (setq-local comment-start systemd-comment-start)
-  (setq-local font-lock-defaults '(systemd-font-lock-keywords)))
+  (set-keymap-parent systemd-mode-map nil)
+  (conf-mode-initialize systemd-comment-start)
+  (setq-local auto-fill-inhibit-regexp "^[ \t]*?[^;#]")
+  (add-hook 'completion-at-point-functions #'systemd-complete-at-point nil t)
+  (add-hook 'font-lock-extend-region-functions
+            'systemd-font-lock-extend-region nil t)
+  (setq-local syntax-propertize-function #'systemd-syntax-propertize)
+  (setq font-lock-defaults
+        '((systemd-font-lock-keywords
+           systemd-font-lock-keywords-1
+           systemd-font-lock-keywords-2
+           systemd-font-lock-keywords-3))))
 
 (provide 'systemd)
 

test/systemd-tests.el

@@ -0,0 +1,85 @@
+;;; systemd-tests.el --- Tests for systemd.el -*- lexical-binding: t -*-
+
+;; Copyright (C) 2016-2020  Mark Oteiza <mvoteiza@udel.edu>
+
+;; Author: Mark Oteiza <mvoteiza@udel.edu>
+
+;; This file 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 file 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 file. If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(require 'ert)
+(require 'systemd)
+
+(ert-deftest test-normal-autoloads ()
+  "Tests for `systemd-autoload-regexp'.
+This should match unit names: alpha-numeric ascii base names,
+with exceptions in the set [-_.@\\]. Extensions are a prescribed
+list.  Some from systemd.unit(5) are excluded intentionally;
+e.g. scope files which are created programmatically."
+  (let ((re systemd-autoload-regexp))
+    (should (string-match-p re "70-snark-ethernet.link"))
+    (should-not (string-match-p re "abusname"))
+    (should-not (string-match-p re "busname"))
+    ;; Do not match empty unit name
+    (should-not (string-match-p re ".service"))
+    ;; Non-alphanumeric ASCII exceptions
+    (should (string-match-p re "-.mount"))
+    (should (string-match-p re "dev-dm\\x2d4.service"))
+    (should (string-match-p re "proc-sys-fs-binfmt_misc.automount"))
+    (should (string-match-p re "bitlbee@.service"))
+    (should (string-match-p re "org.freedesktop.timedate1.busname"))
+    ;; Do not match non-ASCII
+    (should-not (string-match-p re "割り箸.service"))
+    ;; Do not match non-alphanumeric ASCII
+    (should-not (string-match-p re "~.service"))))
+
+(ert-deftest test-tempfile-autoloads ()
+  "Tests for `systemd-tempfn-autoload-regexp'.
+Should match file names generated by \"tempfn_random\" in
+src/basic/fileio.c which, to quote its comments, does the
+transformation
+
+  /foo/bar/waldo  =>  /foo/bar/.#<extra>waldobaa2a261115984a9
+
+but not plain unit names.  For temp files made from systemctl
+edit, <extra> is NULL as of systemd 229."
+  (let ((re systemd-tempfn-autoload-regexp))
+    (should-not (string-match-p re "/foo/bar/.#waldobaa2a261115984a9"))
+    (should (string-match-p re ".#override.conf064d87263873e7f7"))
+    (should (string-match-p re ".#FOObar.timer064d87263873e7f7"))
+    ;; Do not match just the conf extension or unit names
+    (should-not (string-match-p re "override.conf"))
+    (should-not (string-match-p re "mmmmm.mount"))))
+
+(ert-deftest test-dropin-autoloads ()
+  "Tests for `systemd-dropin-autoload-regexp'.
+It should match file names with the \".conf\" extension if and
+only if in an appropriately named parent directory."
+  (let ((re systemd-dropin-autoload-regexp))
+    (should (string-match-p re "/systemd/dog.socket.d/woof.conf"))
+    (should-not (string-match-p re "foobar.conf"))
+    (should-not (string-match-p re "/etc/modprobe.d/bonding.conf"))
+    (should-not (string-match-p re "/etc/systemd/system.conf"))
+    ;; No restrictions on the base name
+    (should (string-match-p re ".config/systemd/user/foo.timer.d/კულტის.conf"))
+    (should (string-match-p re "/etc/systemd/user/c.service.d/a\nb.conf"))
+    ;; Do not match inside a subdirectory of foobar.d/
+    (should-not (string-match-p re ".config/systemd/user/foo.timer.d/a/b.conf"))))
+
+(provide 'systemd-tests)
+
+;;; systemd-tests.el ends here

unit-directives.txt

@@ -0,0 +1,360 @@
+Accept
+AccuracySec
+After
+Alias
+AllowIsolate
+AllowedCPUs
+AllowedMemoryNodes
+Also
+AmbientCapabilities
+AppArmorProfile
+AssertACPower
+AssertArchitecture
+AssertCapability
+AssertControlGroupController
+AssertDirectoryNotEmpty
+AssertFileIsExecutable
+AssertFileNotEmpty
+AssertFirstBoot
+AssertGroup
+AssertHost
+AssertKernelCommandLine
+AssertKernelVersion
+AssertNeedsUpdate
+AssertPathExists
+AssertPathExistsGlob
+AssertPathIsDirectory
+AssertPathIsMountPoint
+AssertPathIsReadWrite
+AssertPathIsSymbolicLink
+AssertSecurity
+AssertUser
+AssertVirtualization
+Backlog
+Before
+BindIPv6Only
+BindPaths
+BindReadOnlyPaths
+BindToDevice
+BindsTo
+BlockIOAccounting
+BlockIODeviceWeight
+BlockIOReadBandwidth
+BlockIOWeight
+BlockIOWriteBandwidth
+Broadcast
+BusName
+CPUAccounting
+CPUAffinity
+CPUQuota
+CPUQuotaPeriodSec
+CPUSchedulingPolicy
+CPUSchedulingPriority
+CPUSchedulingResetOnFork
+CPUShares
+CPUWeight
+CacheDirectory
+CacheDirectoryMode
+CapabilityBoundingSet
+CollectMode
+ConditionACPower
+ConditionArchitecture
+ConditionCPUs
+ConditionCapability
+ConditionControlGroupController
+ConditionDirectoryNotEmpty
+ConditionFileIsExecutable
+ConditionFileNotEmpty
+ConditionFirstBoot
+ConditionGroup
+ConditionHost
+ConditionKernelCommandLine
+ConditionKernelVersion
+ConditionMemory
+ConditionNeedsUpdate
+ConditionPathExists
+ConditionPathExistsGlob
+ConditionPathIsDirectory
+ConditionPathIsMountPoint
+ConditionPathIsReadWrite
+ConditionPathIsSymbolicLink
+ConditionSecurity
+ConditionUser
+ConditionVirtualization
+ConfigurationDirectory
+ConfigurationDirectoryMode
+Conflicts
+DefaultDependencies
+DefaultInstance
+DeferAcceptSec
+Delegate
+Description
+DeviceAllow
+DevicePolicy
+DirectoryMode
+DirectoryNotEmpty
+DisableControllers
+Documentation
+DynamicUser
+Environment
+EnvironmentFile
+ExecCondition
+ExecReload
+ExecStart
+ExecStartPost
+ExecStartPre
+ExecStop
+ExecStopPost
+ExecStopPre
+FailureAction
+FailureActionExitStatus
+FileDescriptorName
+FileDescriptorStoreMax
+FinalKillSignal
+ForceUnmount
+FreeBind
+Group
+GuessMainPID
+IOAccounting
+IODeviceLatencyTargetSec
+IODeviceWeight
+IOReadBandwidthMax
+IOReadIOPSMax
+IOSchedulingClass
+IOSchedulingPriority
+IOWeight
+IOWriteBandwidthMax
+IOWriteIOPSMax
+IPAccounting
+IPAddressAllow
+IPAddressDeny
+IPEgressFilterPath
+IPIngressFilterPath
+IPTOS
+IPTTL
+IgnoreOnIsolate
+IgnoreSIGPIPE
+InaccessiblePaths
+JobRunningTimeoutSec
+JobTimeoutAction
+JobTimeoutRebootArgument
+JobTimeoutSec
+JoinsNamespaceOf
+KeepAlive
+KeepAliveIntervalSec
+KeepAliveProbes
+KeepAliveTimeSec
+KeyringMode
+KillMode
+KillSignal
+LazyUnmount
+LimitAS
+LimitCORE
+LimitCPU
+LimitDATA
+LimitFSIZE
+LimitLOCKS
+LimitMEMLOCK
+LimitMSGQUEUE
+LimitNICE
+LimitNOFILE
+LimitNPROC
+LimitRSS
+LimitRTPRIO
+LimitRTTIME
+LimitSIGPENDING
+LimitSTACK
+ListenDatagram
+ListenFIFO
+ListenMessageQueue
+ListenNetlink
+ListenSequentialPacket
+ListenSpecial
+ListenStream
+ListenUSBFunction
+LockPersonality
+LogExtraFields
+LogLevelMax
+LogRateLimitBurst
+LogRateLimitIntervalSec
+LogsDirectory
+LogsDirectoryMode
+MakeDirectory
+Mark
+MaxConnections
+MaxConnectionsPerSource
+MemoryAccounting
+MemoryDenyWriteExecute
+MemoryHigh
+MemoryLimit
+MemoryLow
+MemoryMax
+MemoryMin
+MemorySwapMax
+MessageQueueMaxMessages
+MessageQueueMessageSize
+MountAPIVFS
+MountFlags
+NUMAMask
+NUMAPolicy
+NetworkNamespacePath
+Nice
+NoDelay
+NoNewPrivileges
+NonBlocking
+NotifyAccess
+OOMPolicy
+OOMScoreAdjust
+OnActiveSec
+OnBootSec
+OnCalendar
+OnClockChange
+OnFailure
+OnFailureJobMode
+OnStartupSec
+OnTimezoneChange
+OnUnitActiveSec
+OnUnitInactiveSec
+Options
+PAMName
+PIDFile
+PartOf
+PassCredentials
+PassEnvironment
+PassSecurity
+PathChanged
+PathExists
+PathExistsGlob
+PathModified
+Persistent
+Personality
+PipeSize
+Priority
+PrivateDevices
+PrivateMounts
+PrivateNetwork
+PrivateTmp
+PrivateUsers
+PropagatesReloadTo
+ProtectControlGroups
+ProtectHome
+ProtectHostname
+ProtectKernelLogs
+ProtectKernelModules
+ProtectKernelTunables
+ProtectSystem
+RandomizedDelaySec
+ReadOnlyPaths
+ReadWritePaths
+RebootArgument
+ReceiveBuffer
+RefuseManualStart
+RefuseManualStop
+ReloadPropagatedFrom
+RemainAfterElapse
+RemainAfterExit
+RemoveIPC
+RemoveOnStop
+RequiredBy
+Requires
+RequiresMountsFor
+Requisite
+Restart
+RestartForceExitStatus
+RestartKillSignal
+RestartPreventExitStatus
+RestartSec
+RestrictAddressFamilies
+RestrictNamespaces
+RestrictRealtime
+RestrictSUIDSGID
+ReusePort
+RootDirectory
+RootDirectoryStartOnly
+RootImage
+RuntimeDirectory
+RuntimeDirectoryMode
+RuntimeDirectoryPreserve
+RuntimeMaxSec
+SELinuxContext
+SELinuxContextFromNet
+SecureBits
+SendBuffer
+SendSIGHUP
+SendSIGKILL
+Service
+Slice
+SloppyOptions
+SmackLabel
+SmackLabelIPIn
+SmackLabelIPOut
+SmackProcessLabel
+SocketGroup
+SocketMode
+SocketProtocol
+SocketUser
+Sockets
+SourcePath
+StandardError
+StandardInput
+StandardInputData
+StandardInputText
+StandardOutput
+StartLimitAction
+StartLimitBurst
+StartLimitIntervalSec
+StartupBlockIOWeight
+StartupCPUShares
+StartupCPUWeight
+StartupIOWeight
+StateDirectory
+StateDirectoryMode
+StopWhenUnneeded
+SuccessAction
+SuccessActionExitStatus
+SuccessExitStatus
+SupplementaryGroups
+Symlinks
+SyslogFacility
+SyslogIdentifier
+SyslogLevel
+SyslogLevelPrefix
+SystemCallArchitectures
+SystemCallErrorNumber
+SystemCallFilter
+TCPCongestion
+TTYPath
+TTYReset
+TTYVHangup
+TTYVTDisallocate
+TasksAccounting
+TasksMax
+TemporaryFileSystem
+TimeoutAbortSec
+TimeoutCleanSec
+TimeoutIdleSec
+TimeoutSec
+TimeoutStartSec
+TimeoutStopSec
+TimerSlackNSec
+Transparent
+TriggerLimitBurst
+TriggerLimitIntervalSec
+Type
+UMask
+USBFunctionDescriptors
+USBFunctionStrings
+Unit
+UnsetEnvironment
+User
+UtmpIdentifier
+UtmpMode
+WakeSystem
+WantedBy
+Wants
+WatchdogSec
+WatchdogSignal
+What
+Where
+WorkingDirectory
+Writable