;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012-2014, 2016-2017, 2020-2022 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2013 Nikita Karetnikov <nikita@karetnikov.org>
;;; Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
;;; Copyright © 2018 Tim Gesthuizen <tim.gesthuizen@yahoo.de>
;;; Copyright © 2021, 2023 Simon Tournier <zimon.toutoune@gmail.com>
;;; Copyright © 2021 Sarah Morgensen <iskarian@mgsn.dev>
;;;
;;; 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 scripts hash)
#:use-module (gcrypt hash)
#:use-module (guix ui)
#:use-module (guix hash)
#:use-module (guix scripts)
#:use-module (guix base16)
#:use-module (guix base32)
#:autoload (guix base64) (base64-encode)
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-37)
#:autoload (disarchive git-hash) (git-hash-file git-hash-directory)
#:export (guix-hash))
;;;
;;; Serializers
;;;
(define* (nar-hash file #:optional
(algorithm (assoc-ref %default-options 'hash-algorithm))
select?)
(file-hash* file #:algorithm algorithm #:select? select? #:recursive? #true))
(define* (default-hash file #:optional
(algorithm (assoc-ref %default-options 'hash-algorithm))
select?)
(match file
("-" (port-hash algorithm (current-input-port)))
(_ (file-hash* file #:algorithm algorithm #:recursive? #false))))
(define* (git-hash file #:optional
(algorithm (assoc-ref %default-options 'hash-algorithm))
select?)
(define directory?
(case (stat:type (stat file))
((directory) #t)
(else #f)))
(if directory?
(git-hash-directory file algorithm #:select? select?)
(git-hash-file file algorithm)))
;;;
;;; Command-line options.
;;;
(define %default-options
;; Alist of default option values.
`((format . ,bytevector->nix-base32-string)
(hash-algorithm . ,(hash-algorithm sha256))
(serializer . ,default-hash)))
(define (show-help)
(display (G_ "Usage: guix hash [OPTION] FILE
Return the cryptographic hash of FILE.\n"))
(newline)
(display (G_ "\
Supported formats: 'base64', 'nix-base32' (default), 'base32',
and 'base16' ('hex' and 'hexadecimal' can be used as well).\n"))
(format #t (G_ "
-x, --exclude-vcs exclude version control directories"))
(format #t (G_ "
-H, --hash=ALGORITHM use the given hash ALGORITHM"))
(format #t (G_ "
-f, --format=FMT write the hash in the given format"))
(format #t (G_ "
-S, --serializer=TYPE compute the hash on FILE according to TYPE serialization"))
(newline)
(display (G_ "
-h, --help display this help and exit"))
(display (G_ "
-V, --version display version information and exit"))
(newline)
(show-bug-report-information))
(define %options
;; Specification of the command-line options.
(list (option '(#\x "exclude-vcs") #f #f
(lambda (opt name arg result)
(alist-cons 'exclude-vcs? #t result)))
(option '(#\H "hash") #t #f
(lambda (opt name arg result)
(match (lookup-hash-algorithm (string->symbol arg))
(#f
(leave (G_ "~a: unknown hash algorithm~%") arg))
(algo
(alist-cons 'hash-algorithm algo result)))))
(option '(#\f "format") #t #f
(lambda (opt name arg result)
(define fmt-proc
(match arg
("base64"
base64-encode)
("nix-base32"
bytevector->nix-base32-string)
("base32"
bytevector->base32-string)
((or "base16" "hex" "hexadecimal")
bytevector->base16-string)
(x
(leave (G_ "unsupported hash format: ~a~%")
arg))))
(alist-cons 'format fmt-proc
(alist-delete 'format result))))
(option '(#\r "recursive") #f #f
(lambda (opt name arg result)
(unless (eqv? name #\r)
(warning (G_ "'--recursive' is deprecated, \
use '--serializer=nar' instead~%")))
(alist-cons 'serializer nar-hash
(alist-delete 'serializer result))))
(option '(#\S "serializer") #t #f
(lambda (opt name arg result)
(define serializer-proc
(match arg
("none"
default-hash)
("nar"
nar-hash)
("git"
git-hash)
(x
(leave (G_ "unsupported serializer type: ~a~%")
arg))))
(alist-cons 'serializer serializer-proc
(alist-delete 'serializer result))))
(option '(#\h "help") #f #f
(lambda args
(leave-on-EPIPE (show-help))
(exit 0)))
(option '(#\V "version") #f #f
(lambda args
(show-version-and-exit "guix hash")))))
;;;
;;; Entry point.
;;;
(define-command (guix-hash . args)
(category packaging)
(synopsis "compute the cryptographic hash of a file")
(define (parse-options)
;; Return the alist of option values.
(parse-command-line args %options (list %default-options)
#:build-options? #f))
(let* ((opts (parse-options))
(args (filter-map (match-lambda
(('argument . value)
value)
(_ #f))
(reverse opts)))
(fmt (assq-ref opts 'format))
(algorithm (assoc-ref opts 'hash-algorithm))
(serializer (assoc-ref opts 'serializer)))
(define (file-hash file)
;; Compute the hash of FILE.
;; Catch and gracefully report possible error
(catch 'system-error
(lambda _
(with-error-handling
(let ((select? (if (assq-ref opts 'exclude-vcs?)
(negate (vcs-file-predicate file))
(const #t))))
(serializer file algorithm select?))))
(lambda args
(leave (G_ "~a ~a~%")
file
(strerror (system-error-errno args))))))
(define (formatted-hash thing)
(fmt (file-hash thing)))
(match args
(()
(leave (G_ "no arguments specified~%")))
(_
(for-each
(compose (cute format #t "~a~%" <>) formatted-hash)
args)))))