* gnu/services/base.scm (<gpm-configuration>): New record type.
(gpm-dmd-service): New procedure.
(gpm-service-type): New variable.
(gpm-service): New procedure.
* doc/guix.texi (Base Services): Document it.
* gnu/services/base.scm (<guix-publish-configuration>): New record
type.
(guix-publish-dmd-service): New procedure.
(%guix-publish-accounts, guix-publish-service-type): New variables.
(guix-publish-service): New procedure.
* doc/guix.texi (Invoking guix publish): Add xref to
'guix-publish-service' anchor.
(Base Services): Document 'guix-publish-service'.
* gnu/services/desktop.scm (<udisks-configuration>): New record type.
(udisks-service-type): New variable.
(udisks-service): New procedure.
(%desktop-services): Use it.
* doc/guix.texi (Desktop Services): Document it.
* gnu/packages/polkit.scm (polkit)[source]: Adjust snippet so that rules
and actions are looked for under /etc/polkit-1.
* gnu/services/desktop.scm (<polkit-configuration>): New record type.
(polkit-directory, polkit-etc-files, polkit-setuid-programs): New
procedures.
(polkit-service-type)[compose, extend]: New fields.
(polkit-service): Refine docstring.
(colord-service-type): Extend POLKIT-SERVICE-TYPE.
(elogind-configuration-file): Extend POLKIT-SERVICE-TYPE.
* doc/guix.texi (Desktop Services): Update 'polkit-service'
documentation.
* gnu/services/networking.scm (tor-dmd-service): Take a 'config'
parameter and honor it.
(tor-service): Take a 'config-file' parameter. Pass it in the
service's value.
* doc/guix.texi (Networking Services): Adjust accordingly.
Fixes a regression introduced in commit 0adfe95.
* gnu/system.scm (other-file-system-services)[requirements]: Remove.
[add-dependencies]: New procedure.
Use it.
* gnu/system/file-systems.scm (<file-system>)[dependencies]: Update
comment.
* gnu/services/base.scm (mapped-device->dmd-service-name,
dependency->dmd-service-name): New procedures.
(file-system-service-type): Use it.
* gnu/services.scm (%modify-service, modify-services): New macros.
* gnu/services/base.scm (mingetty-service-type, guix-service-type):
Export.
* emacs/guix-devel.el (guix-devel-keywords): Add 'modify-services'.
Ditto in 'guix-devel-scheme-indent' call.
* doc/guix.texi (Using the Configuration System): Give an example of
'modify-services'.
(Service Reference): Document it.
* gnu/services/base.scm (<guix-configuration>)[substitute-urls]: New
field.
(guix-dmd-service): Honor it.
* doc/guix.texi (Base Services): Document it.
* gnu/services/dbus.scm (dbus-dmd-service): Rewrite using 'match-lambda'
so that the config's dbus package is used. Fixes a regression
introduced in 64643b9.
* gnu/services/dbus.scm (dbus-etc-files): New procedure.
(dbus-dmd-service): Remove the use of '--config-file'.
(dbus-configuration-directory): Adjust accordingly.
(dbus-root-service-type): Add extension of ETC-SERVICE-TYPE.
* gnu/services/base.scm (user-unmount-service-type): Change label and
dmd name to 'user-file-systems'.
(user-processes-service-type)[requirement]: Add 'user-file-systems'.
* gnu/services/avahi.scm (avahi-service): Mention the extension of
nscd.
* doc/guix.texi (Networking Services): Update accordingly.
(Name Service Switch): Remove '%my-base-services' example and
explanation.
This patch rewrites GuixSD services to make them extensible.
* gnu-system.am (GNU_SYSTEM_MODULES): Add gnu/services/dbus.scm.
* gnu/services.scm (<service>): Replace with new record type.
(<service-extension>, <service-type>): New record types.
(write-service-type, compute-boot-script, second-argument): New
procedures.
(%boot-service, boot-service-type): New variables.
(file-union, directory-union, modprobe-wrapper,
activation-service->script, activation-script,
gexps->activation-gexp): New procedures.
(activation-service-type, %activation-service): New variables.
(etc-directory, files->etc-directory, etc-service): New procedures.
(etc-service-type, setuid-program-service, firmware-service-type): New
variables.
(firmware->activation-gexp): New procedure.
(&service-error, &missing-target-service-error,
&ambiguous-target-service-error): New condition types.
(service-back-edges, fold-services): New procedures.
* gnu/services/avahi.scm (<avahi-configuration>): New record type.
(configuration-file): Replace keyword parameters with a single
'config' parameter.
(%avahi-accounts, %avahi-activation, avahi-service-type): New
variables.
(avahi-dmd-service): New procedure.
(avahi-service): Rewrite using 'service' and 'avahi-configuration'.
* gnu/services/base.scm (%root-file-system-dmd-service,
root-file-system-service-type): New variables.
(root-file-system-service): Use them.
(file-system->dmd-service-name): New procedure.
(file-system-service-type): New variable.
(file-system-service): Use it. Replace keyword parameters with a
single 'file-system' object.
(user-unmount-service-type): New variable.
(user-unmount-service): Use it.
(user-processes-service-type): New variable.
(user-processes-service): Use it.
(host-name-service-type): New variable.
(host-name-service): Use it.
(console-keymap-service-type): New variable.
(console-keymap-service): Use it.
(console-font-service-type): New variable.
(console-font-service): Use it.
(mingetty-pam-service, mingetty-dmd-service): New procedures.
(mingetty-service-type): New variable.
(mingetty-service): Use it.
(nscd-dmd-service): New procedure.
(nscd-activation, nscd-service-type): New variables.
(nscd-service): Use the latter.
(syslog-service-type): New variable.
(syslog-service): Use it.
(<guix-configuration>): New record type.
(%default-guix-configuration): New variable.
(guix-dmd-service, guix-accounts, guix-activation): New procedures.
(guix-service-type): New variable.
(guix-service): Replace list of keyword parameters with a single
'config' parameter. Rewrite using 'service'.
(<udev-configuration>): New record type.
(udev-dmd-service): New procedure.
(udev-service-type): New variable.
(udev-service): Use it.
(device-mapping-service-type): New variable.
(device-mapping-service): Use it.
(swap-service-type): New variable.
(swap-service): Use it.
* gnu/services/databases.scm (<postgresql-configuration>): New record
type.
(%postgresql-accounts, postgresql-activation): New variables.
(postgresql-dmd-service): New procedure.
(postgresql-service): Rewrite using 'service' and
'postgresql-configuration'.
* gnu/services/dbus.scm: New file.
* gnu/services/desktop.scm (dbus-configuration-directory, dbus-service):
Remove.
(wrapped-dbus-service): New procedure.
(<upower-configuration>): New record type.
(upower-configuration-file): Replace keyword parameters with single
<upower-configuration> parameter.
(%upower-accounts, %upower-activation): New variables.
(upower-dbus-service, upower-dmd-service): New procedures.
(upower-service-type): New variable.
(upower-service): Rewrite using 'service' and 'upower-configuration'.
(%colord-activation, %colord-accounts): New variables.
(colord-dmd-service): New procedure.
(colord-service-type): New variable.
(colord-service): Rewrite using 'service'.
(<geoclue-configuration>): New record type.
(geoclue-configuration-file): Replace keyword parameters with a single
'config' parameter.
(geoclue-dbus-service, geoclue-dmd-service): New procedures.
(%geoclue-accounts, geoclue-service-type): New variables.
(geoclue-service): Rewrite using 'service' and
'geoclue-configuration'.
(%polkit-accounts, %polkit-pam-services, polkit-service-type): New
variables.
(polkit-dmd-service): New procedure.
(polkit-service): Rewrite using 'service'.
(<elogind-configuration>)[elogind]: New field.
(elogind-dmd-service): New procedure.
(elogind-service-type): New variable.
(elogind-service): Rewrite using 'service'.
(%desktop-services): Remove argument to 'dbus-service'. Remove 'map'
over %BASE-SERVICES.
* gnu/services/dmd.scm (dmd-boot-gexp): New procedure.
(dmd-root-service-type, %dmd-root-service): New variables.
(dmd-service-type): New macro.
(<dmd-service>): New record type.
* gnu/services/lirc.scm (<lirc-configuration>): New record type.
(%lirc-activation): New variable.
(lirc-dmd-service): New procedure.
(lirc-service-type): New variable.
(lirc-service): Rewrite using 'service' and 'lirc-configuration'.
* gnu/services/networking.scm (<static-networking>): New record type.
(static-networking-service-type): New variable.
(static-networking-service): Rewrite using 'service' and
'static-networking'.
(dhcp-client-service-type): New variable.
(dhcp-client-service): Rewrite using 'service'.
(<ntp-configuration>): New record type.
(ntp-dmd-service): New procedure.
(ntp-service-type): New variable.
(ntp-service): New procedure.
(%tor-accounts, tor-service-type): New variable.
(tor-dmd-service): New procedure.
(tor-service): Rewrite using 'service'.
(<bitlbee-configuration>): New record type.
(bitlbee-dmd-service): New procedure.
(%bitlbee-accounts, %bitlbee-activation, bitlbee-service-type): New
variables.
(bitlbee-service): Rewrite using 'service'.
(%wicd-activation): New variable.
(wicd-dmd-service): New procedure.
(wicd-service-type): New variable.
(wicd-service): Rewrite using 'service'.
* gnu/services/ssh.scm (<lsh-configuration>): New record type.
(activation): Rename to...
(lsh-initialization): ... this.
(lsh-activation, lsh-dmd-service, lsh-pam-services): New procedures.
(lsh-service-type): New variable.
(lsh-service): Rewrite using 'service' and 'lsh-configuration'.
* gnu/services/web.scm (<nginx-configuration>): New record type.
(%nginx-accounts): New variable.
(nginx-activation, nginx-dmd-service): New procedures.
(nginx-service-type): New variable.
(nginx-service): Rewrite using 'service' and 'nginx-configuration'.
* gnu/services/xorg.scm (<slim-configuration>): New record type.
(slim-pam-service, slim-dmd-service): New procedures.
(slim-service-type): New variable.
(slim-service): Rewrite using 'service' and 'slim-configuration'.
* gnu/system.scm (file-union): Remove.
(other-file-system-services): Adjust to new 'file-system-service'
signature.
(essential-services): Add #:container? parameter. Add
%DMD-ROOT-SERVICE, %ACTIVATION-SERVICE, and calls to
'pam-root-service', 'account-service', 'operating-system-etc-service',
and a SETUID-PROGRAM-SERVICE instance.
(operating-system-services): Pass #:container? to 'essential-services.
(etc-directory): Remove.
(operating-system-etc-service): New procedure. Rewrite as a call to
'etc-service'.
(operating-system-accounts): Change to not return accounts required by
services.
(operating-system-etc-directory): Rewrite as a call to 'fold-services'
and 'etc-directory'.
(user-group->gexp, user-account->gexp, modprobe-wrapper): Remove.
(operating-system-activation-script): Rewrite as a call to
'fold-services' and 'activation-service->script'.
(operating-system-boot-script): Likewise.
(operating-system-derivation): Add call to 'lower-object'.
(emacs-site-file, emacs-site-directory, shells-file): Change to use
'computed-file' and 'scheme-file' instead of the monadic procedures.
* gnu/system/install.scm (cow-store-service-type): New variable.
(cow-store-service): Rewrite using 'service'.
(/etc/configuration-files): New procedure.
(configuration-template-service-type,
%configuration-template-service): New variables.
(configuration-template-service): Remove.
(installation-services): Adjust accordingly. Adjust argument to
'guix-service'.
* gnu/system/linux.scm (/etc-entry, pam-root-service): New procedures.
(pam-root-service-type): New variable.
* gnu/system/shadow.scm (user-group->gexp, user-account->gexp,
account-activation, etc-skel, account-service): New procedures.
(account-service-type): New variable.
* tests/services.scm: New file.
* doc/guix.texi (Base Services, Desktop Services): Adjust accordingly.
(Defining Services): Rewrite.
* doc/images/service-graph.dot: New file.
* doc.am (DOT_FILES): Add it.
* po/guix/POTFILES.in: Add gnu/services.scm.
* gnu/services/base.scm (<nscd-configuration>)[glibc, name-services]:
New fields.
(nscd-service): Remove #:glibc and #:name-services parameters. Adjust
body to take those from CONFIG.
* gnu/services/desktop.scm (%desktop-services): Adjust accordingly.
* doc/guix.texi (Base Services): Adjust accordingly.
(Name Service Switch): Adjust example.
* gnu/services/avahi.scm (configuration-file): Use 'plain-file' instead
of 'text-file'.
(avahi-service): Turn into a regular procedure that returns a <service>.
* gnu/services/base.scm (root-file-system-service, file-system-service,
user-unmount-service, user-processes-service, host-name-service,
console-keymap-service, console-font-service, mingetty-service,
nscd.conf-file, nscd-service): Likewise.
(%default-syslog.conf): New variable.
(syslog-service): Use it. Turn into a regular procedure.
(guix-service, udev-rules-union, kvm-udev-rule, udev-service,
device-mapping-service, swap-service): Likewise.
* gnu/services/databases.scm (%default-postgres-hba,
%default-postgres-ident): Use 'plain-file' instead of 'text-file'.
(%default-postgres-config): Use 'mixed-text-file' instead of
'text-file*'.
(postgresql-service): Use 'program-file' instead of 'gexp->script'.
Turn into a regular procedure.
* gnu/services/desktop.scm (dbus-configuration-directory): Use
'computed-file' instead of 'gexp->derivation'.
(upower-configuration-file, geoclue-configuration-file,
elogind-configuration-file): Use 'plain-file' instead of 'text-file'.
(dbus-service, upower-service, colord-service, geoclue-service,
polkit-service, elogind-service): Turn into regular procedures.
(%desktop-services): Remove use of 'mlet' when iterating on
%BASE-SERVICES.
* gnu/services/lirc.scm (lirc-service): Turn into a regular procedure.
* gnu/services/networking.scm (static-networking-service,
dhcp-client-service, ntp-service, tor-service, bitlbee-service,
wicd-service): Likewise.
* gnu/services/ssh.scm (lsh-service): Likewise.
* gnu/services/web.scm (nginx-service): Likewise.
* gnu/services/xorg.scm (xorg-configuration-file): Use 'mixed-text-file'
instead of 'text-file*'.
(xorg-start-command, slim-service): Turn into regular procedures.
(xinitrc): Use 'program-file' instead of 'gexp->script'.
* gnu/system/install.scm (cow-store-service,
configuration-template-service): Turn into regular procedures.
* gnu/system.scm (other-file-system-services, device-mapping-services,
swap-services, essential-services, operating-system-services,
user-shells, operating-system-accounts): Remove now unnecessary
'mlet' and turn into regular procedures.
(operating-system-etc-directory, operating-system-activation-script,
operating-system-boot-script): Adjust accordingly.
* doc/guix.texi (Base Services, Networking Services, X Window, Desktop
Services, Database Services, Web Services, Various Services, Name
Service Switch): Adjust accordingly.
* gnu/services/base.scm (mingetty-service): Change default value of
#:motd from a monadic value to a <plain-file>. Assume MOTD to be a
file-like object. Assume LOGIN-PROGRAM is a gexp or #f.
(%base-services): Use 'plain-file' instead of 'text-file' for motd.
* gnu/system/linux.scm (unix-pam-service): Update docstring to mention
that MOTD is a file-like object.
* doc/guix.texi (Base Services): Adjust 'mingetty-service' documentation
accordingly.
* gnu/system/install.scm (installation-services): Adjust accordingly.
(log-to-info): Use 'program-file' instead of 'gexp->script'.
* gnu/services/base.scm (mingetty-service): Change default value of
#:motd from a monadic value to a <plain-file>. Assume MOTD to be a
file-like object. Assume LOGIN-PROGRAM is a gexp or #f.
(%base-services): Use 'plain-file' instead of 'text-file' for motd.
* gnu/system/linux.scm (unix-pam-service): Update docstring to mention
that MOTD is a file-like object.
* doc/guix.texi (Base Services): Adjust 'mingetty-service' documentation
accordingly.
* gnu/services/desktop.scm (%desktop-services): Replace the 'udev-service'
from %base-services.
* gnu/services/base.scm (%base-services): Add a comment to keep them in sync.
* gnu/services/desktop.scm (<elogind-configuration>): New record type.
(elogind-configuration-file, elogind-service): New functions.
(%desktop-services): Add elogind-service.
* gnu/services/desktop.scm (bool): New top-level helper.
(upower-configuration-file): Use top-level `bool'.
(geoclue-application): New public function.
(%standard-geoclue-applications): New public variable.
(geoclue-service): New public variable.
(%desktop-services): Add GeoClue. Add a comment about activation.
* doc/guix.texi (Desktop Services): Document the GeoClue service.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>
* gnu/services/xorg.scm (xorg-configuration-file): New procedure, with code
formerly in 'xorg-start-command'.
(xorg-start-command): Remove #:drivers and #:resolutions; add
#:configuration-file; use it as well as 'xorg-configuration-file'.
Somehow, as of Linux 4.0.2, the interfaces are down by default, which
prevents 'dhclient' from actually using them.
* gnu/services/networking.scm (dhcp-client-service): Call
'set-network-interface-up' on each item of IFACES.
* gnu/services/colord.scm, gnu/services/dbus.scm,
gnu/services/upower.scm: Remove.
* gnu/services/desktop.scm: New file, with contents taken from the above
files.
* gnu-system.am (GNU_SYSTEM_MODULES): Adjust accordingly.
* doc/guix.texi (Desktop Services): New section.
(Various Services): Move colord-service and upower-service from
here to "Desktop Services".
* gnu/build/file-systems.scm (MS_REMOUNT): New constant.
(mount-file-system): Add 'flags' local variable. When FLAGS has
MS_BIND & MS_RDONLY, call 'mount' with MS_REMOUNT.
* gnu/services/base.scm (file-system-service) <start>: Likewise.
* gnu/services/avahi.scm (avahi-service): Change 'shell' to a gexp
referring to "nologin" in the SHADOW package.
* gnu/services/dbus.scm (dbus-service): Likewise.
* gnu/services/networking.scm (ntp-service, tor-service): Likewise.
* doc/guix.texi (Name Service Switch): Add link to nss-mdns. Add
example show how to pass #:name-services to 'nscd-service'.
(Base Services): Add link from 'nscd-service' to the above.
* gnu/services/base.scm (nscd-service): Update docstring accordingly.
Reported by 白い熊 @相撲道 <guix-devel_gnu.org@sumou.com>
at <http://lists.gnu.org/archive/html/guix-devel/2015-03/msg00264.html>.
* gnu/services/dmd.scm (assert-no-duplicates): New procedure.
(dmd-configuration-file): Use it.
* po/guix/POTFILES.in: Add gnu/services/dmd.scm.
* tests/guix-system.sh (errorfile): Add test.
Previously processes started from the window manager would have a couple
of leaked file descriptors: writable /var/log/slim.log and readable
/gnu/store/…-xinitrc.
* gnu/services/xorg.scm (xinitrc)[builder]: Add 'close-all-fdes'. Use
it in 'exec-from-login-shell'.
That makes WindowMaker the default session, by default.
* gnu/services/xorg.scm (xsessions-directory)[builder]: Prepend a number
in the file name to preserve the order of SESSIONS.
(slim-service): Augment docstring.
* doc/guix.texi (X Window): Adjust accordingly.
* gnu/services/base.scm (nscd-service): Add #:name-services parameter.
In 'start' field, set LD_LIBRARY_PATH based on #:name-services.
* doc/guix.texi (Base Services): Document it.
(Name Service Switch): Link to 'nscd-service'.
* gnu/services/xorg.scm (<session-type>): New record type.
(%windowmaker-session-type, %ratpoison-session-type): New variables.
(%default-xsessions): Use them.
(xsessions-directory): Expect SESSIONS to be a list of <session-type>
and rewrite accordingly.
(slim-service): Adjust docstring.
* doc/guix.texi (X Window): Update accordingly.
Includes fixes for CVE-2014-8091, CVE-2014-8092, CVE-2014-8093, CVE-2014-8094,
CVE-2014-8095, CVE-2014-8096, CVE-2014-8097, CVE-2014-8098, CVE-2014-8099,
CVE-2014-8100, CVE-2014-8101, CVE-2014-8102, and CVE-2014-8103.
See <http://www.x.org/wiki/Development/Security/Advisory-2014-12-09/>
* gnu/packages/xorg.scm (xorg-server): Update to 1.16.2.901. Move mesa,
resourceproto, scrnsaverproto, and xf86driproto from inputs to
propagated-inputs. Add dri3proto and presentproto to propagated-inputs.
Add eudev and libxshmfence to inputs. Add a 'pre-configure' phase instead
of modifying the 'configure' phase. Adapt substitution that avoids trying
to 'mkdir /var' to build system changes.
* gnu/services/xorg.scm (xserver.conf): Add xf86-input-evdev ModulePath line.
* gnu/packages/xorg.scm (xf86-video-modesetting): Remove a comment stating
that the libdrm used in this driver is incompatible with the one in mesa,
because it is no longer true.
* gnu/services/xorg.scm (xserver.conf): Uncomment 'xf86-video-modesetting'
ModulePath and remove associated comment.
Before that, as it was given an empty configuration file, nscd would
actually have all its caches disabled.
* gnu/services/base.scm (<nscd-configuration>, <nscd-cache>): New record
types.
(%nscd-default-caches, %nscd-default-configuration): New variables.
(nscd.conf-file): New procedure.
(nscd-service): Add 'config' parameter. Use 'nscd.conf-file', and
pass its result as the '-f' parameter of nscd.
* doc/guix.texi (Base Services): Update 'nscd-service' documentation
accordingly. Document 'nscd-configuration', 'nscd-cache',
'%nscd-default-configuration', and '%nscd-default-caches'.
This is a followup to 1d18d87, which fixes <http://bugs.gnu.org/19119>.
* gnu/services/xorg.scm (xinitrc)[builder]: Add 'exec-from-login-shell'
procedure. Use it instead of 'execl' when launching XSESSION, WMAKER,
or RATPOISON.
Suggested by Adam Pribyl <pribyl@lowlevel.cz>.
* gnu/services/ssh.scm (lsh-service): Update docstring with xrefs to
the lsh manual. Fix typos.
* doc/guix.texi (Networking Services): Synchronize.
Fixes <http://bugs.gnu.org/19119>.
Reported by David Thompson <dthompson2@worcester.edu>.
* gnu/services/xorg.scm (xinitrc): Augment $PATH to include
~/.guix-profile/bin.
* gnu/artwork.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.
* gnu/services/xorg.scm: Use it.
(%artwork-repository): Remove.
* gnu/system/grub.scm: Use it.
(%artwork-repository): Remove.
* gnu/services/base.scm (user-unmount-service): New procedure.
* gnu/system.scm (essential-services): Use it.
* gnu/system/install.scm (cow-store-service): Mention it in comment.
* gnu/services/xorg.scm (xorg-start-command): Add #:drivers parameter.
Add 'device-section' procedure, and use it in 'xserver.conf'.
* doc/guix.texi (X Window): Document it.
* gnu/packages/xorg.scm (xf86-video-modesetting): New variable.
* gnu/services/xorg.scm (xorg-start-command)[xserver.conf]: Add
ModulePath line for XF86-VIDEO-MODESETTING, commented out.
* gnu/services/base.scm (user-processes-service): Increase the default
value of 'grace-delay'. This leaves more time for processes to clean
up their PID files, /tmp/.X0-lock, etc.
* gnu/packages/xorg.scm (xf86-input-vmmouse): Remove. This driver
implement the mouse protocol of a proprietary emulator.
* gnu/services/xorg.scm (xorg-start-command): Remove reference.
* gnu/services/base.scm (kvm-udev-rule): New procedure.
(udev-service): Use it, and add it to RULES.
(guix-build-accounts): Add "kvm" to the 'supplementary-groups' field.
* gnu/system/shadow.scm (%base-groups): Add "kvm".
* gnu/services/base.scm (swap-service): New procedure.
* gnu/system.scm (<operating-system>)[swap-devices]: New field.
(swap-services): New procedure.
(essential-services): Use it.
* gnu/system/file-systems.scm (<mapped-device-type>): New record type.
(<mapped-device>)[command]: Remove field.
[type]: New field.
* gnu/services/base.scm (device-mapping-service): Rename 'command'
parameter to 'open'. Add 'close' parameter and honor it.
* gnu/system.scm (luks-device-mapping): Rename to...
(open-luks-device): ... this.
(close-luks-device): New procedure.
(luks-device-mapping): New variable.
(device-mapping-services): Get the type of MD, and pass its 'open' and
'close' fields to 'device-mapping-service'.
Reported by DusXMT on #guix.
* gnu/services/networking.scm (static-networking-service): Add
'requirement' field. Change 'documentation' to be a string literal.
* gnu/system/file-systems.scm (<mapped-device>): New record type.
* gnu/system.scm (<operating-system>)[mapped-devices]: New field.
(luks-device-mapping): New procedure.
(other-file-system-services)[device-mappings, requirements]: New
procedures. Pass #:requirements to 'file-system-service'.
(device-mapping-services): New procedure.
(essential-services): Use it. Append its result to the return value.
(operating-system-initrd-file): Add comment.
* gnu/services/base.scm (file-system-service): Add #:requirements
parameter and honor it.
(device-mapping-service): New procedure.
* gnu/system/linux-initrd.scm (base-initrd): Add comment.
* gnu/services/base.scm (udev-rules-union): New procedure.
(udev-service): Add #:rules parameter. Call 'udev-rules-union' and
create udev.conf. Set $UDEV_CONFIG_FILE before spawning udevd.
