What about this patch? Is there a way to compose the following part somehow to prevent a possible race condition?
(rename-file prog prog-real)
(with-output-to-file prog (lambda ()
(format #t
"#!~a~%~a~%exec ~a~%"
(which "bash")
(string-join (map export-variable vars)
"\n")
(canonicalize-path prog-real))))
(chmod prog #o755)))
From 6bd8c169c320ffe9dd13a85a6f63a60b8508bc3c Mon Sep 17 00:00:00 2001
From: Nikita Karetnikov <nik...@karetnikov.org>
Date: Sat, 2 Mar 2013 20:08:39 +0000
Subject: [PATCH] utils: Add 'wrap-program'.
* guix/build/utils.scm (wrap-program): New procedure.
---
guix/build/utils.scm | 40 +++++++++++++++++++++++++++++++++++++++-
1 files changed, 39 insertions(+), 1 deletions(-)
diff --git a/guix/build/utils.scm b/guix/build/utils.scm
index 6921e31..2bff789 100644
--- a/guix/build/utils.scm
+++ b/guix/build/utils.scm
@@ -1,5 +1,6 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012, 2013 Ludovic Courtès <l...@gnu.org>
+;;; Copyright © 2013 Nikita Karetnikov <nik...@karetnikov.org>
;;;
;;; This file is part of GNU Guix.
;;;
@@ -49,7 +50,8 @@
patch-shebang
patch-makefile-SHELL
fold-port-matches
- remove-store-references))
+ remove-store-references
+ wrap-program))
;;;
@@ -605,6 +607,42 @@ known as `nuke-refs' in Nixpkgs."
(put-u8 out (char->integer char))
result))))))
+(define* (wrap-program prog #:rest vars)
+ "Rename PROG to .PROG-real and make PROG a wrapper."
+ (let ((prog-real (string-append "." prog "-real")))
+ (define (export-variable lst)
+ ;; Return a string that exports an environment variable.
+ (match lst
+ ((var sep '= rest)
+ (format #f "export ~a=\"~a\""
+ var (string-join rest sep)))
+ ((var sep 'prefix rest)
+ (format #f "export ~a=\"~a${~a~a+~a}$~a\""
+ var (string-join rest sep) var sep sep var))
+ ((var sep 'suffix rest)
+ (format #f "export ~a=\"$~a${~a~a+~a}~a\""
+ var var var sep sep (string-join rest sep)))
+ ((var '= rest)
+ (format #f "export ~a=\"~a\""
+ var (string-join rest ":")))
+ ((var 'prefix rest)
+ (format #f "export ~a=\"~a${~a:+:}$~a\""
+ var (string-join rest ":") var var))
+ ((var 'suffix rest)
+ (format #f "export ~a=\"$~a${~a:+:}~a\""
+ var var var (string-join rest ":")))))
+
+ (rename-file prog prog-real)
+
+ (with-output-to-file prog (lambda ()
+ (format #t
+ "#!~a~%~a~%exec ~a~%"
+ (which "bash")
+ (string-join (map export-variable vars)
+ "\n")
+ (canonicalize-path prog-real))))
+ (chmod prog #o755)))
+
;;; Local Variables:
;;; eval: (put 'call-with-output-file/atomic 'scheme-indent-function 1)
;;; eval: (put 'with-throw-handler 'scheme-indent-function 1)
--
1.7.5.4
pgpmr73YE4upi.pgp
Description: PGP signature
