build-aux/download.scm

   1 ;;; Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
   2 ;;; Copyright (C) 2012, 2013 Ludovic Courtès <ludo@gnu.org>
   3 ;;;
   4 ;;; This file is part of Guix.
   5 ;;;
   6 ;;; Guix is free software; you can redistribute it and/or modify it
   7 ;;; under the terms of the GNU General Public License as published by
   8 ;;; the Free Software Foundation; either version 3 of the License, or (at
   9 ;;; your option) any later version.
  10 ;;;
  11 ;;; Guix is distributed in the hope that it will be useful, but
  12 ;;; WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;;; GNU General Public License for more details.
  15 ;;;
  16 ;;; You should have received a copy of the GNU General Public License
  17 ;;; along with Guix.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 ;;;
  20 ;;; Download a binary file from an external source.
  21 ;;;
  22
  23 (use-modules (ice-9 match)
  24              (web uri)
  25              (web client)
  26              (rnrs io ports)
  27              (srfi srfi-11)
  28              (guix utils))
  29
  30 (define %url-base
  31   "http://www.fdn.fr/~lcourtes/software/guix/packages")
  32
  33 (define (file-name->uri file)
  34   "Return the URI for FILE."
  35   (match (string-tokenize file (char-set-complement (char-set #\/)))
  36     ((_ ... system basename)
  37      (string->uri (string-append %url-base "/" system
  38                                  "/20130105/" basename)))))
  39
  40 (match (command-line)
  41   ((_ file expected-hash)
  42    (let ((uri (file-name->uri file)))
  43      (format #t "downloading file `~a' from `~a'...~%"
  44              file (uri->string uri))
  45      (let*-values (((resp data) (http-get uri #:decode-body? #f))
  46                    ((hash)      (bytevector->base16-string (sha256 data)))
  47                    ((part)      (string-append file ".part")))
  48        (if (string=? expected-hash hash)
  49            (begin
  50              (call-with-output-file part
  51                (lambda (port)
  52                  (put-bytevector port data)))
  53              (rename-file part file))
  54            (begin
  55              (format (current-error-port)
  56                      "file at `~a' has SHA256 ~a; expected ~a~%"
  57                      (uri->string uri) hash expected-hash)
  58              (exit 1)))))))