gnu: Add the 'glib-or-gtk' build system.

* guix/build-system/glib-or-gtk.scm, guix/build/glib-or-gtk-build-system.scm:
  New files.
* Makefile.am (MODULES): Add them.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

3 files changed, 327 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
index e623978fc9..7eecef23ba 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -47,6 +47,7 @@ MODULES =					\
   guix/licenses.scm				\
   guix/build-system.scm				\
   guix/build-system/cmake.scm			\
+  guix/build-system/glib-or-gtk.scm		\
   guix/build-system/gnu.scm			\
   guix/build-system/perl.scm			\
   guix/build-system/python.scm			\
@@ -61,6 +62,7 @@ MODULES =					\
   guix/build/download.scm			\
   guix/build/cmake-build-system.scm		\
   guix/build/git.scm				\
+  guix/build/glib-or-gtk-build-system.scm	\
   guix/build/gnu-build-system.scm		\
   guix/build/gnu-dist.scm			\
   guix/build/perl-build-system.scm		\
diff --git a/guix/build-system/glib-or-gtk.scm b/guix/build-system/glib-or-gtk.scm
new file mode 100644
index 0000000000..078d5f6e8a
--- /dev/null
+++ b/guix/build-system/glib-or-gtk.scm
@@ -0,0 +1,195 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013 Cyril Roelandt <tipecaml@gmail.com>
+;;; Copyright © 2014 Federico Beffa <beffa@fbengineering.ch>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix 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.
+;;;
+;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix build-system glib-or-gtk)
+  #:use-module (guix store)
+  #:use-module (guix utils)
+  #:use-module (guix derivations)
+  #:use-module (guix build-system)
+  #:use-module (guix build-system gnu)
+  #:use-module (guix packages)
+  #:use-module (ice-9 match)
+  #:export (glib-or-gtk-build
+            glib-or-gtk-build-system))
+
+;; Commentary:
+;;
+;; This build system is an extension of the 'gnu-build-system'.  It
+;; accomodates the needs of applications making use of glib or gtk+ (with "or"
+;; to be interpreted in the mathematical sense).  This is achieved by adding
+;; two phases run after the 'install' phase:
+;;
+;; 'glib-or-gtk-wrap' phase:
+;;
+;; a) This phase looks for GSettings schemas by verifying the existence of
+;; path "datadir/glib-2.0/schemas" in all input packages.  If the path is
+;; found in any package, then all programs in "out/bin" are wrapped in scripts
+;; where the environment variable "XDG_DATA_DIRS" is set and points to the
+;; list of found schemas directories.
+;;
+;; b) Looks for the existence of "libdir/gtk-3.0" directories in all input
+;; packages.  If any is found, then the environment variable "GTK_PATH" is
+;; suitably set and added to the wrappers.  The variable "GTK_PATH" has been
+;; preferred over "GTK_EXE_PREFIX" because the latter can only point to a
+;; single directory, while we may need to point to several ones.
+;;
+;; 'glib-or-gtk-compile-schemas' phase:
+;;
+;; Looks for the presence of "out/share/glib-2.0/schemas".  If that directory
+;; exists and does not include a file named "gschemas.compiled", then
+;; "glib-compile-schemas" is run in that directory.
+;;
+;; Code:
+
+(define %default-modules
+  ;; Build-side modules made available in the build environment.
+  '((guix build glib-or-gtk-build-system)
+    (guix build utils)))
+
+(define %default-imported-modules
+  ;; Build-side modules imported and used by default.
+  '((guix build gnu-build-system)
+    (guix build glib-or-gtk-build-system)
+    (guix build utils)))
+
+(define (default-glib)
+  "Return the default glib package from which we use
+\"glib-compile-schemas\"."
+  ;; Do not use `@' to avoid introducing circular dependencies.
+  (let ((module (resolve-interface '(gnu packages glib))))
+    (module-ref module 'glib)))
+
+(define* (lower name
+                #:key source inputs native-inputs outputs system target
+                (glib (default-glib)) (implicit-inputs? #t)
+                (strip-binaries? #t)
+                #:allow-other-keys
+                #:rest arguments)
+  "Return a bag for NAME."
+  (define private-keywords
+    '(#:source #:target #:glib #:inputs #:native-inputs
+      #:outputs #:implicit-inputs?))
+
+  (and (not target)                               ;XXX: no cross-compilation
+       (bag
+         (name name)
+         (system system)
+         (host-inputs `(,@(if source
+                              `(("source" ,source))
+                              '())
+                        ,@inputs))
+         (build-inputs `(("glib:bin" ,glib)
+                         ,@(if implicit-inputs?
+                               (standard-packages)
+                               '())
+                         ,@native-inputs))
+         (outputs outputs)
+         (build glib-or-gtk-build)
+         (arguments (strip-keyword-arguments private-keywords arguments)))))
+
+(define* (glib-or-gtk-build store name inputs
+                            #:key (guile #f)
+                            (outputs '("out"))
+                            (search-paths '())
+                            (configure-flags ''())
+                            (make-flags ''())
+                            (out-of-source? #t)
+                            (tests? #t)
+                            (test-target "check")
+                            (parallel-build? #t)
+                            (parallel-tests? #t)
+                            (patch-shebangs? #t)
+                            (strip-binaries? #t)
+                            (strip-flags ''("--strip-debug"))
+                            (strip-directories ''("lib" "lib64" "libexec"
+                                                  "bin" "sbin"))
+                            (phases '(@ (guix build glib-or-gtk-build-system)
+                                        %standard-phases))
+                            (system (%current-system))
+                            (imported-modules %default-imported-modules)
+                            (modules %default-modules)
+                            allowed-references)
+  "Build SOURCE with INPUTS.  See GNU-BUILD for more details."
+  (define canonicalize-reference
+    (match-lambda
+     ((? package? p)
+      (derivation->output-path (package-derivation store p system)))
+     (((? package? p) output)
+      (derivation->output-path (package-derivation store p system)
+                               output))
+     ((? string? output)
+      output)))
+
+  (define builder
+    `(begin
+       (use-modules ,@modules)
+       (glib-or-gtk-build #:source ,(match (assoc-ref inputs "source")
+                                      (((? derivation? source))
+                                       (derivation->output-path source))
+                                      ((source)
+                                       source)
+                                      (source
+                                       source))
+                          #:system ,system
+                          #:outputs %outputs
+                          #:inputs %build-inputs
+                          #:search-paths ',(map search-path-specification->sexp
+                                                search-paths)
+                          #:phases ,phases
+                          #:configure-flags ,configure-flags
+                          #:make-flags ,make-flags
+                          #:out-of-source? ,out-of-source?
+                          #:tests? ,tests?
+                          #:test-target ,test-target
+                          #:parallel-build? ,parallel-build?
+                          #:parallel-tests? ,parallel-tests?
+                          #:patch-shebangs? ,patch-shebangs?
+                          #:strip-binaries? ,strip-binaries?
+                          #:strip-flags ,strip-flags
+                          #:strip-directories ,strip-directories)))
+
+  (define guile-for-build
+    (match guile
+      ((? package?)
+       (package-derivation store guile system))
+      (#f                                         ; the default
+       (let* ((distro (resolve-interface '(gnu packages commencement)))
+              (guile  (module-ref distro 'guile-final)))
+         (package-derivation store guile system)))))
+
+  (build-expression->derivation store name builder
+                                #:system system
+                                #:inputs inputs
+                                #:modules imported-modules
+                                #:outputs outputs
+                                #:allowed-references
+                                (and allowed-references
+                                     (map canonicalize-reference
+                                          allowed-references))
+                                #:guile-for-build guile-for-build))
+
+(define glib-or-gtk-build-system
+  (build-system
+    (name 'glib-or-gtk)
+    (description
+     "The GNU Build System—i.e., ./configure && make && make install,
+augmented with definition of suitable environment variables for glib and gtk+
+in program wrappers.")
+    (lower lower)))
diff --git a/guix/build/glib-or-gtk-build-system.scm b/guix/build/glib-or-gtk-build-system.scm
new file mode 100644
index 0000000000..1d87a4cf27
--- /dev/null
+++ b/guix/build/glib-or-gtk-build-system.scm
@@ -0,0 +1,130 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014 Federico Beffa <beffa@fbengineering.ch>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix 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.
+;;;
+;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix build glib-or-gtk-build-system)
+  #:use-module ((guix build gnu-build-system) #:prefix gnu:)
+  #:use-module (guix build utils)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 regex)
+  #:use-module (srfi srfi-1)
+  #:export (%standard-phases
+            glib-or-gtk-build))
+
+;; Commentary:
+;;
+;; Builder-side code of the standard glib-or-gtk build procedure.
+;;
+;; Code:
+
+(define (subdirectory-exists? parent sub-directory)
+  (directory-exists? (string-append parent sub-directory)))
+
+(define (directory-included? directory directories-list)
+  "Is DIRECTORY included in DIRECTORIES-LIST?"
+  (fold (lambda (s p) (or (string-ci=? s directory) p)) 
+        #f directories-list))
+
+(define (gtk-module-directories inputs)
+  "Check for the existence of \"libdir/gtk-v.0\" in INPUTS.  Return a list
+with all found directories."
+  (let* ((version 
+          (if (string-match "gtk\\+-3" 
+                            (or (assoc-ref inputs "gtk+")
+                                (assoc-ref inputs "source")
+                                "gtk+-3")) ; we default to version 3
+              "3.0"
+              "2.0"))
+         (gtk-module
+          (lambda (input prev)
+            (let* ((in (match input
+                         ((_ . dir) dir)
+                         (_ "")))
+                   (libdir 
+                    (string-append in "/lib/gtk-" version)))
+              (if (and (directory-exists? libdir)
+                       (not (directory-included? libdir prev)))
+                  (cons libdir prev)
+                  prev)))))
+    (fold gtk-module '() inputs)))
+
+(define (schemas-directories inputs)
+  "Check for the existence of \"datadir/glib-2.0/schemas\" in INPUTS.  Return
+a list with all found directories."
+  (define (glib-schemas input previous)
+    (let* ((in (match input
+                 ((_ . dir) dir)
+                 (_ "")))
+           (datadir (string-append in "/share")))
+      (if (and (subdirectory-exists? datadir "/glib-2.0/schemas")
+               (not (directory-included? datadir previous)))
+          (cons datadir previous)
+          previous)))
+
+  (fold glib-schemas '() inputs))
+
+(define* (wrap-all-programs #:key inputs outputs #:allow-other-keys)
+  "Implement phase \"glib-or-gtk-wrap\": look for GSettings schemas and
+gtk+-v.0 libraries and create wrappers with suitably set environment variables
+if found."
+  (let* ((out (assoc-ref outputs "out"))
+         (bindir (string-append out "/bin"))
+         (bin-list (find-files bindir ".*"))
+         (schemas (schemas-directories (acons "out" out inputs)))
+         (schemas-env-var 
+          (if (not (null? schemas))
+              `("XDG_DATA_DIRS" ":" prefix ,schemas)
+              #f))
+         (gtk-mod-dirs (gtk-module-directories (acons "out" out inputs)))
+         (gtk-mod-env-var 
+          (if (not (null? gtk-mod-dirs))
+              `("GTK_PATH" ":" prefix ,gtk-mod-dirs)
+              #f)))
+    (cond
+     ((and schemas-env-var gtk-mod-env-var)
+      (map (lambda (prog) 
+             (wrap-program prog schemas-env-var gtk-mod-env-var))
+           bin-list))
+     (schemas-env-var
+      (map (lambda (prog) (wrap-program prog schemas-env-var)) bin-list))
+     (gtk-mod-env-var
+      (map (lambda (prog) (wrap-program prog gtk-mod-env-var)) bin-list)))))
+
+(define* (compile-glib-schemas #:key inputs outputs #:allow-other-keys)
+  "Implement phase \"glib-or-gtk-compile-schemas\": compile \"glib\" schemas
+if needed."
+  (let* ((out (assoc-ref outputs "out"))
+         (schemasdir (string-append out "/share/glib-2.0/schemas")))
+    (if (and (directory-exists? schemasdir)
+             (not (file-exists? 
+                   (string-append schemasdir "/gschemas.compiled"))))
+        (system* "glib-compile-schemas" schemasdir)
+        #t)))
+
+(define %standard-phases
+  (alist-cons-after
+   'install 'glib-or-gtk-wrap wrap-all-programs 
+   (alist-cons-after 
+    'install 'glib-or-gtk-compile-schemas compile-glib-schemas 
+    gnu:%standard-phases)))
+
+(define* (glib-or-gtk-build #:key inputs (phases %standard-phases)
+                            #:allow-other-keys #:rest args)
+  "Build the given package, applying all of PHASES in order."
+  (apply gnu:gnu-build #:inputs inputs #:phases phases args))
+
+;;; glib-or-gtk-build-system.scm ends here