cuirass/src/cuirass/utils.scm

84 lines
3.1 KiB
Scheme

;;; utils.scm -- helper procedures
;;; Copyright © 2012, 2013, 2016 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2015 David Thompson <davet@gnu.org>
;;; Copyright © 2016 Mathieu Lirzin <mthl@gnu.org>
;;;
;;; This file is part of Cuirass.
;;;
;;; Cuirass 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.
;;;
;;; Cuirass 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 Cuirass. If not, see <http://www.gnu.org/licenses/>.
(define-module (cuirass utils)
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:export (;; Procedures
alist?
mkdir-p
make-user-module
;; Macros.
λ*
with-directory-excursion))
(define-syntax-rule (λ* formals body ...)
(lambda* formals body ...))
(define (alist? obj)
"Return #t if OBJ is an alist."
(and (list? obj)
(every pair? obj)))
(define mkdir-p
(let ((not-slash (char-set-complement (char-set #\/))))
(λ* (dir #:optional mode)
"Create directory DIR and all its ancestors."
(let ((absolute? (string-prefix? "/" dir)))
(let loop ((components (string-tokenize dir not-slash))
(root (if absolute? "" ".")))
(match components
((head tail ...)
(let ((dir-name (string-append root "/" head)))
(catch 'system-error
(λ ()
(if mode
(mkdir dir-name mode)
(mkdir dir-name))
(loop tail dir-name))
(λ args
;; On GNU/Hurd we can get EROFS instead of EEXIST here.
;; Thus, if we get something other than EEXIST, check
;; whether DIR-NAME exists. See
;; <https://lists.gnu.org/archive/html/guix-devel/2016-02/msg00049.html>.
(if (or (= EEXIST (system-error-errno args))
(let ((st (stat dir-name #f)))
(and st (eq? 'directory (stat:type st)))))
(loop tail dir-name)
(apply throw args))))))
(() #t)))))))
(define-syntax-rule (with-directory-excursion dir body ...)
"Run BODY with DIR as the process's current directory."
(let ((init (getcwd)))
(dynamic-wind
(λ () (chdir dir))
(λ () body ...)
(λ () (chdir init)))))
(define* (make-user-module #:optional (modules '()))
"Return a new user module with the additional MODULES loaded."
;; Module in which the machine description file is loaded.
(let ((module (make-fresh-user-module)))
(for-each (lambda (iface)
(module-use! module (resolve-interface iface)))
modules)
module))