store: (direct-store-path? (%store-prefix)) returns #f.

* guix/store.scm (direct-store-path?): Return #f if PATH
  is (%store-prefix).
* tests/store.scm ("direct-store-path?"): Add test.

gnu: Use gexps in obvious places in (gnu system ...).

* gnu/system.scm (operating-system-boot-script): Use 'gexp->file'
  instead of 'text-file*'.
* gnu/system/vm.scm (expression->derivation-in-linux-vm): Likewise.
  (system-qemu-image/shared-store-script)[builder]: Turn into a gexp.
  Use 'gexp->derivation' instead of 'derivation-expression'.

Add (guix gexp).

* guix/gexp.scm: New file.
* tests/gexp.scm: New file.
* Makefile.am (MODULES): Add guix/gexp.scm.
  (SCM_TESTS): Add tests/gexp.scm.
* doc/guix.texi (Derivations): Add #:inputs in 'derivation' example.
  Mark 'build-expression->derivation' as deprecated, refer to
  "G-Expressions".  Remove paragraph about code strata.
  (G-Expressions): New node.

gnu: soprano: Add input clucene.

* gnu/packages/rdf.scm (soprano): Add input clucene and patch the cmake
    file looking for it.
* gnu/packages/patches/soprano-find-clucene.patch: New file.
* gnu-system.am (dist_patch_DATA): Register the patch.

gnu: soprano: Upgrade to 2.9.4.

* gnu/packages/rdf.scm (soprano): Upgrade to 2.9.4.

guix: cmake: Add input and package libraries to the rpath, and adapt package
  definitions accordingly.

* guix/build/cmake-build-system.scm (configure): Add flags.
* gnu/packages/maths.scm (lapack): Drop special code.
* gnu/packages/ssh.scm (libssh): Drop special code.
* gnu/packages/slim.scm (slim): Drop special code and enable shared library.

Co-authored-by: Eric Bavier <bavier@member.fsf.org>

gnu: soprano: Add native input doxygen.

* gnu/packages/rdf.scm (soprano): Add native input doxygen.

gnu: doxygen: Add propagated input graphviz.

* gnu/packages/doxygen.scm (doxygen): Add propagated input graphviz.

gnu: libkate: Add native input doxygen and make input pkg-config native.

* gnu/packages/xiph.scm (libkate): Add native input doxygen.
    Make input pkg-config native.

gnu: libmpdclient: Add native input doxygen.

* gnu/packages/mpd.scm (libmpdclient): Add native input doxygen.

gnu: libdbusmenu-qt: Add native input doxygen for building the documentation,
  and make input qjson native.

* gnu/packages/kde.scm (libdbusmenu-qt): Add native input doxygen for
    building the documentation.
    Make input qjson native, as it is needed only for the tests.

gnu: Add doxygen.

* gnu/packages/doxygen.scm: New file.
* gnu/packages/patches/doxygen-test.patch,
  gnu/packages/patches/doxygen-tmake.patch: New files.
* gnu-system.am (GNU_SYSTEM_MODULES, dist_patch_DATA): Register the new files.

build: Add missing function checks for optional daemon features.

* config-daemon.ac: Check for lchown, posix_fallocate, vfork,
  sched_setaffinity, statvfs, nanosleep, and strsignal.  As a side
  effect, this enables daemon features depending on the corresponding
  feature test macros.

gnu: gp2c: Upgrade to 0.0.9pl1.

* gnu/packages/algebra.scm (gp2c): Upgrade to 0.0.9pl1.

vm: Clarify 'system-qemu-image/shared-store-script'.

* gnu/system/vm.scm (system-qemu-image/shared-store-script): Move
  'initrd' definition to the top-level.  Have a single definition of
  'initrd', 'image', and 'os-drv'.

system: Add 'operating-system-boot-script'.

* gnu/system.scm (operating-system-boot-script): New procedure.
  (operating-system-derivation): Use it.  Remove DMD-CONF from the
  file union.  Add BOOT-DRV to the inputs.

system: Factorize (gnu system).

* gnu/system.scm (operating-system-accounts,
  operating-system-etc-directory): New procedures.
  (operating-system-derivation): Use them.
* gnu/services/base.scm (%base-services): Add 'host-name-service'
  invocation.

gnu: cyrus-sasl: Add alternate source URL.

* gnu/packages/cyrus-sasl.scm (cyrus-sasl)[source]: Add alternate URL;
  the previous one is currently unreachable.

gnu: mplayer: Add mpg123 as an input.

* gnu/packages/video.scm (mplayer)[inputs]: Add mpg123.

gnu: Add mpg123.

* gnu/packages/mp3.scm (mpg123): New variable.