From ddc29a782eac30fcf4ff1f07677aa2896dc140e4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Sun, 11 Nov 2012 22:33:28 +0100 Subject: Move base32 code to (guix base32). * guix/utils.scm (bytevector-quintet-ref, bytevector-quintet-ref-right, bytevector-quintet-length, bytevector-quintet-fold, bytevector-quintet-fold-right, make-bytevector->base32-string, %nix-base32-chars, %rfc4648-base32-chars, bytevector->base32-string, bytevector->nix-base32-string, bytevector-quintet-set!, bytevector-quintet-set-right!, base32-string-unfold, base32-string-unfold-right, make-base32-string->bytevector, base32-string->bytevector, nix-base32-string->bytevector): Move to... * guix/base32.scm: ... here. New file. * tests/utils.scm (%nix-hash, "bytevector->base32-string", "base32-string->bytevector", "nix-base32-string->bytevector", "sha256 & bytevector->base32-string"): Move to... * tests/base32.scm: ... here. New file * guix-download.in, guix/derivations.scm, guix/packages.scm, guix/snix.scm, tests/builders.scm, tests/derivations.scm: Adjust accordingly. * guix.scm (%public-modules): Add `base32'. --- guix/base32.scm | 288 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 288 insertions(+) create mode 100644 guix/base32.scm (limited to 'guix/base32.scm') diff --git a/guix/base32.scm b/guix/base32.scm new file mode 100644 index 0000000000..6f0a92bd99 --- /dev/null +++ b/guix/base32.scm @@ -0,0 +1,288 @@ +;;; Guix --- Nix package management from Guile. -*- coding: utf-8 -*- +;;; Copyright (C) 2012 Ludovic Courtès +;;; +;;; 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 . + +(define-module (guix base32) + #:use-module (srfi srfi-1) + #:use-module (srfi srfi-60) + #:use-module (rnrs bytevectors) + #:use-module (ice-9 vlist) + #:export (bytevector-quintet-length + bytevector->base32-string + bytevector->nix-base32-string + base32-string->bytevector + nix-base32-string->bytevector)) + +;;; Commentary: +;;; +;;; A generic, customizable to convert bytevectors to/from a base32 +;;; representation. +;;; +;;; Code: + +(define bytevector-quintet-ref + (let* ((ref bytevector-u8-ref) + (ref+ (lambda (bv offset) + (let ((o (+ 1 offset))) + (if (>= o (bytevector-length bv)) + 0 + (bytevector-u8-ref bv o))))) + (ref0 (lambda (bv offset) + (bit-field (ref bv offset) 3 8))) + (ref1 (lambda (bv offset) + (logior (ash (bit-field (ref bv offset) 0 3) 2) + (bit-field (ref+ bv offset) 6 8)))) + (ref2 (lambda (bv offset) + (bit-field (ref bv offset) 1 6))) + (ref3 (lambda (bv offset) + (logior (ash (bit-field (ref bv offset) 0 1) 4) + (bit-field (ref+ bv offset) 4 8)))) + (ref4 (lambda (bv offset) + (logior (ash (bit-field (ref bv offset) 0 4) 1) + (bit-field (ref+ bv offset) 7 8)))) + (ref5 (lambda (bv offset) + (bit-field (ref bv offset) 2 7))) + (ref6 (lambda (bv offset) + (logior (ash (bit-field (ref bv offset) 0 2) 3) + (bit-field (ref+ bv offset) 5 8)))) + (ref7 (lambda (bv offset) + (bit-field (ref bv offset) 0 5))) + (refs (vector ref0 ref1 ref2 ref3 ref4 ref5 ref6 ref7))) + (lambda (bv index) + "Return the INDEXth quintet of BV." + (let ((p (vector-ref refs (modulo index 8)))) + (p bv (quotient (* index 5) 8)))))) + +(define bytevector-quintet-ref-right + (let* ((ref bytevector-u8-ref) + (ref+ (lambda (bv offset) + (let ((o (+ 1 offset))) + (if (>= o (bytevector-length bv)) + 0 + (bytevector-u8-ref bv o))))) + (ref0 (lambda (bv offset) + (bit-field (ref bv offset) 0 5))) + (ref1 (lambda (bv offset) + (logior (bit-field (ref bv offset) 5 8) + (ash (bit-field (ref+ bv offset) 0 2) 3)))) + (ref2 (lambda (bv offset) + (bit-field (ref bv offset) 2 7))) + (ref3 (lambda (bv offset) + (logior (bit-field (ref bv offset) 7 8) + (ash (bit-field (ref+ bv offset) 0 4) 1)))) + (ref4 (lambda (bv offset) + (logior (bit-field (ref bv offset) 4 8) + (ash (bit-field (ref+ bv offset) 0 1) 4)))) + (ref5 (lambda (bv offset) + (bit-field (ref bv offset) 1 6))) + (ref6 (lambda (bv offset) + (logior (bit-field (ref bv offset) 6 8) + (ash (bit-field (ref+ bv offset) 0 3) 2)))) + (ref7 (lambda (bv offset) + (bit-field (ref bv offset) 3 8))) + (refs (vector ref0 ref1 ref2 ref3 ref4 ref5 ref6 ref7))) + (lambda (bv index) + "Return the INDEXth quintet of BV, assuming quintets start from the +least-significant bits, contrary to what RFC 4648 describes." + (let ((p (vector-ref refs (modulo index 8)))) + (p bv (quotient (* index 5) 8)))))) + +(define (bytevector-quintet-length bv) + "Return the number of quintets (including truncated ones) available in BV." + (ceiling (/ (* (bytevector-length bv) 8) 5))) + +(define (bytevector-quintet-fold proc init bv) + "Return the result of applying PROC to each quintet of BV and the result of +the previous application or INIT." + (define len + (bytevector-quintet-length bv)) + + (let loop ((i 0) + (r init)) + (if (= i len) + r + (loop (1+ i) (proc (bytevector-quintet-ref bv i) r))))) + +(define (bytevector-quintet-fold-right proc init bv) + "Return the result of applying PROC to each quintet of BV and the result of +the previous application or INIT." + (define len + (bytevector-quintet-length bv)) + + (let loop ((i len) + (r init)) + (if (zero? i) + r + (let ((j (- i 1))) + (loop j (proc (bytevector-quintet-ref-right bv j) r)))))) + +(define (make-bytevector->base32-string quintet-fold base32-chars) + (lambda (bv) + "Return a base32 encoding of BV using BASE32-CHARS as the alphabet." + (let ((chars (quintet-fold (lambda (q r) + (cons (vector-ref base32-chars q) + r)) + '() + bv))) + (list->string (reverse chars))))) + +(define %nix-base32-chars + ;; See `libutil/hash.cc'. + #(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9 + #\a #\b #\c #\d #\f #\g #\h #\i #\j #\k #\l #\m #\n + #\p #\q #\r #\s #\v #\w #\x #\y #\z)) + +(define %rfc4648-base32-chars + #(#\a #\b #\c #\d #\e #\f #\g #\h #\i #\j #\k #\l #\m + #\n #\o #\p #\q #\r #\s #\t #\u #\v #\w #\x #\y #\z + #\2 #\3 #\4 #\5 #\6 #\7)) + +(define bytevector->base32-string + (make-bytevector->base32-string bytevector-quintet-fold + %rfc4648-base32-chars)) + +(define bytevector->nix-base32-string + (make-bytevector->base32-string bytevector-quintet-fold-right + %nix-base32-chars)) + + +(define bytevector-quintet-set! + (let* ((setq! (lambda (bv offset start stop value) + (let ((v (bytevector-u8-ref bv offset)) + (w (arithmetic-shift value start)) + (m (bitwise-xor (1- (expt 2 stop)) + (1- (expt 2 start))))) + (bytevector-u8-set! bv offset + (bitwise-merge m w v))))) + (set0! (lambda (bv offset value) + (setq! bv offset 3 8 value))) + (set1! (lambda (bv offset value) + (setq! bv offset 0 3 (bit-field value 2 5)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 6 8 (bit-field value 0 2))))) + (set2! (lambda (bv offset value) + (setq! bv offset 1 6 value))) + (set3! (lambda (bv offset value) + (setq! bv offset 0 1 (bit-field value 4 5)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 4 8 (bit-field value 0 4))))) + (set4! (lambda (bv offset value) + (setq! bv offset 0 4 (bit-field value 1 5)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 7 8 (bit-field value 0 1))))) + (set5! (lambda (bv offset value) + (setq! bv offset 2 7 value))) + (set6! (lambda (bv offset value) + (setq! bv offset 0 2 (bit-field value 3 5)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 5 8 (bit-field value 0 3))))) + (set7! (lambda (bv offset value) + (setq! bv offset 0 5 value))) + (sets (vector set0! set1! set2! set3! set4! set5! set6! set7!))) + (lambda (bv index value) + "Set the INDEXth quintet of BV to VALUE." + (let ((p (vector-ref sets (modulo index 8)))) + (p bv (quotient (* index 5) 8) (logand value #x1f)))))) + +(define bytevector-quintet-set-right! + (let* ((setq! (lambda (bv offset start stop value) + (let ((v (bytevector-u8-ref bv offset)) + (w (arithmetic-shift value start)) + (m (bitwise-xor (1- (expt 2 stop)) + (1- (expt 2 start))))) + (bytevector-u8-set! bv offset + (bitwise-merge m w v))))) + (set0! (lambda (bv offset value) + (setq! bv offset 0 5 value))) + (set1! (lambda (bv offset value) + (setq! bv offset 5 8 (bit-field value 0 3)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 0 2 (bit-field value 3 5))))) + (set2! (lambda (bv offset value) + (setq! bv offset 2 7 value))) + (set3! (lambda (bv offset value) + (setq! bv offset 7 8 (bit-field value 0 1)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 0 4 (bit-field value 1 5))))) + (set4! (lambda (bv offset value) + (setq! bv offset 4 8 (bit-field value 0 4)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 0 1 (bit-field value 4 5))))) + (set5! (lambda (bv offset value) + (setq! bv offset 1 6 value))) + (set6! (lambda (bv offset value) + (setq! bv offset 6 8 (bit-field value 0 2)) + (or (= (+ 1 offset) (bytevector-length bv)) + (setq! bv (+ 1 offset) 0 3 (bit-field value 2 5))))) + (set7! (lambda (bv offset value) + (setq! bv offset 3 8 value))) + (sets (vector set0! set1! set2! set3! set4! set5! set6! set7!))) + (lambda (bv index value) + "Set the INDEXth quintet of BV to VALUE, assuming quintets start from +the least-significant bits." + (let ((p (vector-ref sets (modulo index 8)))) + (p bv (quotient (* index 5) 8) (logand value #x1f)))))) + +(define (base32-string-unfold f s) + "Given procedure F which, when applied to a character, returns the +corresponding quintet, return the bytevector corresponding to string S." + (define len (string-length s)) + + (let ((bv (make-bytevector (quotient (* len 5) 8)))) + (string-fold (lambda (chr index) + (bytevector-quintet-set! bv index (f chr)) + (+ 1 index)) + 0 + s) + bv)) + +(define (base32-string-unfold-right f s) + "Given procedure F which, when applied to a character, returns the +corresponding quintet, return the bytevector corresponding to string S, +starting from the right of S." + (define len (string-length s)) + + (let ((bv (make-bytevector (quotient (* len 5) 8)))) + (string-fold-right (lambda (chr index) + (bytevector-quintet-set-right! bv index (f chr)) + (+ 1 index)) + 0 + s) + bv)) + +(define (make-base32-string->bytevector base32-string-unfold base32-chars) + (let ((char->value (let loop ((i 0) + (v vlist-null)) + (if (= i (vector-length base32-chars)) + v + (loop (+ 1 i) + (vhash-consv (vector-ref base32-chars i) + i v)))))) + (lambda (s) + "Return the binary representation of base32 string S as a bytevector." + (base32-string-unfold (lambda (chr) + (or (and=> (vhash-assv chr char->value) cdr) + (error "invalid base32 character" chr))) + s)))) + +(define base32-string->bytevector + (make-base32-string->bytevector base32-string-unfold %rfc4648-base32-chars)) + +(define nix-base32-string->bytevector + (make-base32-string->bytevector base32-string-unfold-right %nix-base32-chars)) + +;;; base32.scm ends here -- cgit v1.2.3