Add (guix build rpath).

* guix/build/rpath.scm: New file.
* Makefile.am (MODULES): Add it.
* gnu/packages/python.scm (python): Use it; remove local copy of
  the *rpath* procedures.
* gnu/packages/samba.scm (samba): Likewise.

Makefile.am

@@ -58,6 +58,7 @@ MODULES =					\
   guix/build/perl-build-system.scm		\
   guix/build/utils.scm				\
   guix/build/union.scm				\
+  guix/build/rpath.scm				\
   guix/packages.scm				\
   guix/snix.scm					\
   guix.scm					\

gnu/packages/python.scm

@@ -66,34 +66,16 @@ (define-public python
 
         #:modules ((guix build gnu-build-system)
                    (guix build utils)
-                   (ice-9 popen)
+                   (guix build rpath)
-                   (ice-9 rdelim)
                    (srfi srfi-26))
+        #:imported-modules ((guix build gnu-build-system)
+                            (guix build utils)
+                            (guix build rpath))
 
         #:phases
         (alist-cons-after
          'strip 'add-lib-to-runpath
          (lambda* (#:key outputs #:allow-other-keys)
-           ;; XXX: copied from Samba; TODO: factorize in a module
-
-           (define (file-rpath file)
-             ;; Return the RPATH of FILE.
-             (let* ((p (open-pipe* OPEN_READ "patchelf"
-                                   "--print-rpath" file))
-                    (l (read-line p)))
-               (and (zero? (close-pipe p)) l)))
-
-           (define (augment-rpath file dir)
-             ;; Add DIR to the RPATH of FILE.
-             (let* ((rpath  (file-rpath file))
-                    (rpath* (if rpath
-                                (string-append dir ":" rpath)
-                                dir)))
-               (format #t "~a: changing RPATH from `~a' to `~a'~%"
-                       file (or rpath "") rpath*)
-               (zero? (system* "patchelf" "--set-rpath"
-                               rpath* file))))
-
            (let* ((out (assoc-ref outputs "out"))
                   (lib (string-append out "/lib")))
              ;; Add LIB to the RUNPATH of all the executables.
@@ -107,7 +89,7 @@ (define (augment-rpath file dir)
        ("openssl" ,openssl)
        ("readline" ,readline)
        ("zlib" ,zlib)
-       ("patchelf" ,patchelf)))
+       ("patchelf" ,patchelf)))                   ; for (guix build rpath)
     (native-search-paths
      (list (search-path-specification
             (variable "PYTHONPATH")

gnu/packages/samba.scm

@@ -111,24 +111,6 @@ (define-public samba
                  (alist-cons-after
                   'strip 'add-lib-to-runpath
                   (lambda* (#:key outputs #:allow-other-keys)
-                    (define (file-rpath file)
-                      ;; Return the RPATH of FILE.
-                      (let* ((p (open-pipe* OPEN_READ "patchelf"
-                                            "--print-rpath" file))
-                             (l (read-line p)))
-                        (and (zero? (close-pipe p)) l)))
-
-                    (define (augment-rpath file dir)
-                      ;; Add DIR to the RPATH of FILE.
-                      (let* ((rpath  (file-rpath file))
-                             (rpath* (if rpath
-                                         (string-append dir ":" rpath)
-                                         dir)))
-                        (format #t "~a: changing RPATH from `~a' to `~a'~%"
-                                file (or rpath "") rpath*)
-                        (zero? (system* "patchelf" "--set-rpath"
-                                        rpath* file))))
-
                     (let* ((out (assoc-ref outputs "out"))
                            (lib (string-append out "/lib")))
                       ;; Add LIB to the RUNPATH of all the executables.
@@ -140,9 +122,11 @@ (define (augment-rpath file dir)
 
        #:modules ((guix build gnu-build-system)
                   (guix build utils)
-                  (ice-9 popen)
+                  (guix build rpath)
-                  (ice-9 rdelim)
                   (srfi srfi-26))
+       #:imported-modules ((guix build gnu-build-system)
+                           (guix build utils)
+                           (guix build rpath))
 
        ;; This flag is required to allow for "make test".
        #:configure-flags '("--enable-socket-wrapper")
@@ -163,7 +147,7 @@ (define (augment-rpath file dir)
        ("openldap" ,openldap)
        ("linux-pam" ,linux-pam)
        ("readline" ,readline)
-       ("patchelf" ,patchelf)))
+       ("patchelf" ,patchelf)))                   ; for (guix build rpath)
     (native-inputs                                ; for the test suite
      `(("perl" ,perl)
        ("python" ,python)))

guix/build/rpath.scm

@@ -0,0 +1,59 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2013 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;; 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 rpath)
+  #:use-module (ice-9 popen)
+  #:use-module (ice-9 rdelim)
+  #:export (%patchelf
+            file-rpath
+            augment-rpath))
+
+;;; Commentary:
+;;;
+;;; Tools to manipulate the RPATH and RUNPATH of ELF binaries.  Currently they
+;;; rely on PatchELF.
+;;;
+;;; Code:
+
+(define %patchelf
+  ;; The `patchelf' command.
+  (make-parameter "patchelf"))
+
+(define %not-colon
+  (char-set-complement (char-set #\:)))
+
+(define (file-rpath file)
+  "Return the RPATH (or RUNPATH) of FILE as a list of directory names, or #f
+on failure."
+  (let* ((p (open-pipe* OPEN_READ (%patchelf) "--print-rpath" file))
+         (l (read-line p)))
+    (and (zero? (close-pipe p))
+         (string-tokenize l %not-colon))))
+
+(define (augment-rpath file dir)
+  "Add DIR to the front of the RPATH and RUNPATH of FILE.  Return the new
+RPATH as a list, or #f on failure."
+  (let* ((rpath  (or (file-rpath file) '()))
+         (rpath* (cons dir rpath)))
+    (format #t "~a: changing RPATH from ~s to ~s~%"
+            file rpath rpath*)
+    (and (zero? (system* (%patchelf) "--set-rpath"
+                         (string-join rpath* ":") file))
+         rpath*)))
+
+;;; rpath.scm ends here