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;;; Guix --- Nix package management from Guile. -*- coding: utf-8 -*-
;;; Copyright (C) 2012 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of Guix.
;;;
;;; 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.
;;;
;;; 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 Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix build download)
#:use-module (web uri)
#:use-module (web client)
#:use-module (web response)
#:use-module (guix ftp-client)
#:use-module (guix build utils)
#:use-module (rnrs io ports)
#:use-module (srfi srfi-11)
#:use-module (ice-9 match)
#:export (url-fetch))
;;; Commentary:
;;;
;;; Fetch data such as tarballs over HTTP or FTP (builder-side code).
;;;
;;; Code:
(define (ftp-fetch uri file)
"Fetch data from URI and write it to FILE. Return FILE on success."
(let* ((conn (ftp-open (uri-host uri)))
(in (ftp-retr conn (basename (uri-path uri))
(dirname (uri-path uri)))))
(call-with-output-file file
(lambda (out)
;; TODO: Show a progress bar.
(dump-port in out)))
(ftp-close conn))
file)
(define (open-connection-for-uri uri)
"Return an open input/output port for a connection to URI.
This is the same as Guile's `open-socket-for-uri', except that we always
use a numeric port argument, to avoid the need to go through libc's NSS,
which is not available during bootstrap."
(define addresses
(let ((port (or (uri-port uri)
(case (uri-scheme uri)
((http) 80) ; /etc/services, not for me!
(else
(error "unsupported URI scheme" uri))))))
(getaddrinfo (uri-host uri)
(number->string port)
AI_NUMERICSERV)))
(let loop ((addresses addresses))
(let* ((ai (car addresses))
(s (with-fluids ((%default-port-encoding #f))
(socket (addrinfo:fam ai) (addrinfo:socktype ai)
(addrinfo:protocol ai)))))
(catch 'system-error
(lambda ()
(connect s (addrinfo:addr ai))
;; Buffer input and output on this port.
(setvbuf s _IOFBF)
;; Enlarge the receive buffer.
(setsockopt s SOL_SOCKET SO_RCVBUF (* 12 1024))
s)
(lambda args
;; Connection failed, so try one of the other addresses.
(close s)
(if (null? addresses)
(apply throw args)
(loop (cdr addresses))))))))
;; XXX: This is an awful hack to make sure the (set-port-encoding! p
;; "ISO-8859-1") call in `read-response' passes, even during bootstrap
;; where iconv is not available.
(module-define! (resolve-module '(web response))
'set-port-encoding!
(lambda (p e) #f))
(define (http-fetch uri file)
"Fetch data from URI and write it to FILE. Return FILE on success."
;; FIXME: Use a variant of `http-get' that returns a port instead of
;; loading everything in memory.
(let*-values (((connection)
(open-connection-for-uri uri))
((resp bv)
(http-get uri #:port connection #:decode-body? #f))
((code)
(response-code resp)))
(if (= 200 code)
(begin
(call-with-output-file file
(lambda (p)
(put-bytevector p bv)))
file)
(error "download failed" (uri->string uri)
code (response-reason-phrase resp)))))
(define-syntax-rule (false-if-exception* body ...)
"Like `false-if-exception', but print the exception on the error port."
(catch #t
(lambda ()
body ...)
(lambda (key . args)
#f)
(lambda (key . args)
(print-exception (current-error-port) #f key args))))
(define (url-fetch url file)
"Fetch FILE from URL; URL may be either a single string, or a list of
string denoting alternate URLs for FILE. Return #f on failure, and FILE
on success."
(define uri
(match url
((_ ...) (map string->uri url))
(_ (list (string->uri url)))))
(define (fetch uri file)
(format #t "starting download of `~a' from `~a'...~%"
file (uri->string uri))
(case (uri-scheme uri)
((http) (false-if-exception* (http-fetch uri file)))
((ftp) (false-if-exception* (ftp-fetch uri file)))
(else
(format #t "skipping URI with unsupported scheme: ~s~%"
uri)
#f)))
(setvbuf (current-output-port) _IOLBF)
(setvbuf (current-error-port) _IOLBF)
(let try ((uri uri))
(match uri
((uri tail ...)
(or (fetch uri file)
(try tail)))
(()
(format (current-error-port) "failed to download ~s from ~s~%"
file url)
#f))))
;;; download.scm ends here
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