Merge branch 'master' into core-updates

services: nscd: Make sure /var/db/nscd exists.

* gnu/services/base.scm (nscd-service)[activate]: Make /var/db/nscd.

services: nscd-service: Add #:name-services parameter.

* 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'.

services: mingetty: Wait for udev.

* gnu/services/base.scm (mingetty-service): Add 'udev' to
  'requirement'.

services: guix: #:authorize-hydra-key? now defaults to #t.

* gnu/services/base.scm (guix-service): Change AUTHORIZE-HYDRA-KEY?
  default value to #t.

monads: Move '%store-monad' and related procedures where they belong.

This turns (guix monads) into a generic module for monads, and moves the
store monad and related monadic procedures in their corresponding
module.

* guix/monads.scm (store-return, store-bind, %store-monad, store-lift,
  text-file, interned-file, package-file, package->derivation,
  package->cross-derivation, origin->derivation, imported-modules,
  compiled, modules, built-derivations, run-with-store): Move to...
* guix/store.scm (store-return, store-bind, %store-monad, store-lift,
  text-file, interned-file): ... here.
  (%guile-for-build): New variable.
  (run-with-store): Moved from monads.scm.  Remove default value for
  #:guile-for-build.
* guix/packages.scm (default-guile): Export.
  (set-guile-for-build): New procedure.
  (package-file, package->derivation, package->cross-derivation,
  origin->derivation): Moved from monads.scm.
* guix/derivations.scm (%guile-for-build): Remove.
  (imported-modules): Rename to...
  (%imported-modules): ... this.
  (compiled-modules): Rename to...
  (%compiled-modules): ... this.
  (built-derivations, imported-modules, compiled-modules): New
  procedures.
* gnu/services/avahi.scm, gnu/services/base.scm, gnu/services/dbus.scm,
  gnu/services/dmd.scm, gnu/services/networking.scm,
  gnu/services/ssh.scm, gnu/services/xorg.scm, gnu/system/install.scm,
  gnu/system/linux-initrd.scm, gnu/system/shadow.scm, guix/download.scm,
  guix/gexp.scm, guix/git-download.scm, guix/profiles.scm,
  guix/svn-download.scm, tests/monads.scm: Adjust imports accordingly.
* guix/monad-repl.scm (default-guile-derivation): New procedure.
  (store-monad-language, run-in-store): Use it.
* build-aux/hydra/gnu-system.scm (qemu-jobs): Add explicit
  'set-guile-for-build' call.
* guix/scripts/archive.scm (derivation-from-expression): Likewise.
* guix/scripts/build.scm (options/resolve-packages): Likewise.
* guix/scripts/environment.scm (guix-environment): Likewise.
* guix/scripts/system.scm (guix-system): Likewise.
* doc/guix.texi (The Store Monad): Adjust module names accordingly.

services: user-processes: Really honor the grace delay.

* gnu/services/base.scm (user-processes-service): Change #:grace-delay
  default value to 4.  Define 'sleep*' and use it.

Merge branch 'master' into core-updates

services: user-processes: Write debugging messages to the output port.

* gnu/services/base.scm (user-processes-service): Write "sending all
  processes..." message to the current output port, not to /dev/console.

Merge branch 'master' into core-updates

services: Make 'nscd-service' configurable; cache hosts/services by default.

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'.

services: user-unmount: Change directory to "/" before unmounting.

* gnu/services/base.scm (user-unmount-service): Add 'chdir' call.

services: Add 'user-unmount-service' as an essential service.

* 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.

services: udev: Make /dev/kvm 666 as a workaround.

* gnu/services/base.scm (kvm-udev-rule): Change /dev/kvm mode to 666 to
  work around <http://bugs.gnu.org/18994>.

services: Increase delay before SIGKILL is sent when halting.

* 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.

system: Fix value of 'EUDEV_RULES_DIRECTORY'.

* gnu/services/base.scm (udev-service): Append "/lib/udev/rules.d" to
  EUDEV_RULES_DIRECTORY.

system: Add udev rule for /dev/kvm.

* 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".

system: Add support for swap devices.

* 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.

system: Define 'device-mapping-kind', and add a 'close' procedure.

* 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'.

services: file-system: Change directory to root before unmounting.

* gnu/services/base.scm (file-system-service)[stop]: Add 'chdir' call.