all messages for Guix-related lists mirrored at yhetil.org
 help / color / mirror / code / Atom feed
blob 8f967387adc9078e425d1418db56746a53b5c82d 12512 bytes (raw)
name: gnu/system/uuid.scm 	 # note: path name is non-authoritative(*)

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
 
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2017 Danny Milosavljevic <dannym@scratchpost.org>
;;; Copyright © 2019, 2020 Tobias Geerinckx-Rice <me@tobias.gr>
;;;
;;; 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 (gnu system uuid)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-9)
  #:use-module (rnrs bytevectors)
  #:use-module (ice-9 match)
  #:use-module (ice-9 vlist)
  #:use-module (ice-9 regex)
  #:use-module (ice-9 format)
  #:export (uuid
            uuid?
            uuid-type
            uuid-bytevector
            uuid=?

            bytevector->uuid

            uuid->string
            dce-uuid->string
            string->uuid
            string->dce-uuid
            string->iso9660-uuid
            string->ext2-uuid
            string->ext3-uuid
            string->ext4-uuid
            string->bcachefs-uuid
            string->btrfs-uuid
            string->fat-uuid
            string->jfs-uuid
            string->ntfs-uuid
            string->xfs-uuid
            iso9660-uuid->string

            ;; XXX: For lack of a better place.
            sub-bytevector
            latin1->string))

\f
;;;
;;; Tools that lack a better place.
;;;

(define (sub-bytevector bv start size)
  "Return a copy of the SIZE bytes of BV starting from offset START."
  (let ((result (make-bytevector size)))
    (bytevector-copy! bv start result 0 size)
    result))

(define (latin1->string bv terminator)
  "Return a string of BV, a latin1 bytevector, or #f.  TERMINATOR is a predicate
that takes a number and returns #t when a termination character is found."
    (let ((bytes (take-while (negate terminator) (bytevector->u8-list bv))))
      (if (null? bytes)
          #f
          (list->string (map integer->char bytes)))))

\f
;;;
;;; DCE UUIDs.
;;;

(define-syntax %network-byte-order
  (identifier-syntax (endianness big)))

(define (dce-uuid->string uuid)
  "Convert UUID, a 16-byte bytevector, to its string representation, something
like \"6b700d61-5550-48a1-874c-a3d86998990e\"."
  ;; See <https://tools.ietf.org/html/rfc4122>.
  (let ((time-low  (bytevector-uint-ref uuid 0 %network-byte-order 4))
        (time-mid  (bytevector-uint-ref uuid 4 %network-byte-order 2))
        (time-hi   (bytevector-uint-ref uuid 6 %network-byte-order 2))
        (clock-seq (bytevector-uint-ref uuid 8 %network-byte-order 2))
        (node      (bytevector-uint-ref uuid 10 %network-byte-order 6)))
    (format #f "~8,'0x-~4,'0x-~4,'0x-~4,'0x-~12,'0x"
            time-low time-mid time-hi clock-seq node)))

(define %uuid-rx
  ;; The regexp of a UUID.
  (make-regexp "^([[:xdigit:]]{8})-([[:xdigit:]]{4})-([[:xdigit:]]{4})-([[:xdigit:]]{4})-([[:xdigit:]]{12})$"))

(define (string->dce-uuid str)
  "Parse STR as a DCE UUID (see <https://tools.ietf.org/html/rfc4122>) and
return its contents as a 16-byte bytevector.  Return #f if STR is not a valid
UUID representation."
  (and=> (regexp-exec %uuid-rx str)
         (lambda (match)
           (letrec-syntax ((hex->number
                            (syntax-rules ()
                              ((_ index)
                               (string->number (match:substring match index)
                                               16))))
                           (put!
                            (syntax-rules ()
                              ((_ bv index (number len) rest ...)
                               (begin
                                 (bytevector-uint-set! bv index number
                                                       (endianness big) len)
                                 (put! bv (+ index len) rest ...)))
                              ((_ bv index)
                               bv))))
             (let ((time-low  (hex->number 1))
                   (time-mid  (hex->number 2))
                   (time-hi   (hex->number 3))
                   (clock-seq (hex->number 4))
                   (node      (hex->number 5))
                   (uuid      (make-bytevector 16)))
               (put! uuid 0
                     (time-low 4) (time-mid 2) (time-hi 2)
                     (clock-seq 2) (node 6)))))))

\f
;;;
;;; ISO-9660.
;;;

;; <http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-119.pdf>.

(define %iso9660-uuid-rx
  ;;                   Y                m                d                H                M                S                ss
  (make-regexp "^([[:digit:]]{4})-([[:digit:]]{2})-([[:digit:]]{2})-([[:digit:]]{2})-([[:digit:]]{2})-([[:digit:]]{2})-([[:digit:]]{2})$"))
(define (string->iso9660-uuid str)
  "Parse STR as a ISO9660 UUID (which is really a timestamp - see /dev/disk/by-uuid).
Return its contents as a 16-byte bytevector.  Return #f if STR is not a valid
ISO9660 UUID representation."
  (and=> (regexp-exec %iso9660-uuid-rx str)
         (lambda (match)
           (letrec-syntax ((match-numerals
                            (syntax-rules ()
                              ((_ index (name rest ...) body)
                               (let ((name (match:substring match index)))
                                 (match-numerals (+ 1 index) (rest ...) body)))
                              ((_ index () body)
                               body))))
            (match-numerals 1 (year month day hour minute second hundredths)
              (string->utf8 (string-append year month day
                                           hour minute second hundredths)))))))
(define (iso9660-uuid->string uuid)
  "Given an UUID bytevector, return its timestamp string."
  (define (digits->string bytes)
    (latin1->string bytes (lambda (c) #f)))
  (let* ((year (sub-bytevector uuid 0 4))
         (month (sub-bytevector uuid 4 2))
         (day (sub-bytevector uuid 6 2))
         (hour (sub-bytevector uuid 8 2))
         (minute (sub-bytevector uuid 10 2))
         (second (sub-bytevector uuid 12 2))
         (hundredths (sub-bytevector uuid 14 2))
         (parts (list year month day hour minute second hundredths)))
    (string-append (string-join (map digits->string parts) "-"))))

\f
;;;
;;; FAT32/FAT16.
;;;

(define-syntax %fat-endianness
  ;; Endianness of FAT32/FAT16 file systems.
  (identifier-syntax (endianness little)))

(define (fat-uuid->string uuid)
  "Convert FAT32/FAT16 UUID, a 4-byte bytevector, to its string representation."
  (let ((high  (bytevector-uint-ref uuid 0 %fat-endianness 2))
        (low (bytevector-uint-ref uuid 2 %fat-endianness 2)))
    (format #f "~:@(~4,'0x-~4,'0x~)" low high)))

(define %fat-uuid-rx
  (make-regexp "^([[:xdigit:]]{4})-([[:xdigit:]]{4})$"))

(define (string->fat-uuid str)
  "Parse STR, which is in FAT32/FAT16 format, and return a bytevector or #f."
  (match (regexp-exec %fat-uuid-rx str)
    (#f
     #f)
    (rx-match
     (uint-list->bytevector (list (string->number
                                   (match:substring rx-match 2) 16)
                                  (string->number
                                   (match:substring rx-match 1) 16))
                            %fat-endianness
                            2))))

\f
;;;
;;; NTFS.
;;;

(define-syntax %ntfs-endianness
  ;; Endianness of NTFS file system.
  (identifier-syntax (endianness little)))

(define (ntfs-uuid->string uuid)
  "Convert NTFS UUID, a 8-byte bytevector, to its string representation."
  (format #f "~{~:@(~2,'0x~)~}" (reverse (bytevector->u8-list uuid))))

(define %ntfs-uuid-rx
  (make-regexp "^([[:xdigit:]]{16})$"))

(define (string->ntfs-uuid str)
  "Parse STR, which is in NTFS format, and return a bytevector or #f."
  (match (regexp-exec %ntfs-uuid-rx str)
    (#f
     #f)
    (rx-match
     (u8-list->bytevector
      (let loop ((str str)
                 (res '()))
        (if (string=? str "")
            res
            (loop (string-drop str 2)
                  (cons
                   (string->number (string-take str 2) 16)
                   res))))))))

\f
;;;
;;; Generic interface.
;;;

(define string->ext2-uuid string->dce-uuid)
(define string->ext3-uuid string->dce-uuid)
(define string->ext4-uuid string->dce-uuid)
(define string->bcachefs-uuid string->dce-uuid)
(define string->btrfs-uuid string->dce-uuid)
(define string->f2fs-uuid string->dce-uuid)
(define string->jfs-uuid string->dce-uuid)
(define string->xfs-uuid string->dce-uuid)

(define-syntax vhashq
  (syntax-rules (=>)
    ((_)
     vlist-null)
    ((_ (key others ... => value) rest ...)
     (vhash-consq key value
                  (vhashq (others ... => value) rest ...)))
    ((_ (=> value) rest ...)
     (vhashq rest ...))))

(define %uuid-parsers
  (vhashq
   ('dce 'ext2 'ext3 'ext4 'bcachefs 'btrfs 'f2fs 'jfs 'xfs 'luks
         => string->dce-uuid)
   ('fat32 'fat16 'fat => string->fat-uuid)
   ('ntfs => string->ntfs-uuid)
   ('iso9660 => string->iso9660-uuid)))

(define %uuid-printers
  (vhashq
   ('dce 'ext2 'ext3 'ext4 'bcachefs 'btrfs 'f2fs 'jfs 'xfs 'luks
         => dce-uuid->string)
   ('iso9660 => iso9660-uuid->string)
   ('fat32 'fat16 'fat => fat-uuid->string)
   ('ntfs => ntfs-uuid->string)))

(define* (string->uuid str #:optional (type 'dce))
  "Parse STR as a UUID of the given TYPE.  On success, return the
corresponding bytevector; otherwise return #f."
  (match (vhash-assq type %uuid-parsers)
    (#f #f)
    ((_ . (? procedure? parse)) (parse str))))

;; High-level UUID representation that carries its type with it.
;;
;; This is necessary to serialize bytevectors with the right printer in some
;; circumstances.  For instance, GRUB "search --fs-uuid" command compares the
;; string representation of UUIDs, not the raw bytes; thus, when emitting a
;; GRUB 'search' command, we need to produce the right string representation
;; (see <https://debbugs.gnu.org/cgi/bugreport.cgi?msg=52;att=0;bug=27735>).
(define-record-type <uuid>
  (make-uuid type bv)
  uuid?
  (type  uuid-type)                               ;'dce | 'iso9660 | ...
  (bv    uuid-bytevector))

(define* (bytevector->uuid bv #:optional (type 'dce))
  "Return a UUID object make of BV and TYPE."
  (make-uuid type bv))

(define-syntax uuid
  (lambda (s)
    "Return the UUID object corresponding to the given UUID representation or
#f if the string could not be parsed."
    (syntax-case s (quote)
      ((_ str (quote type))
       (and (string? (syntax->datum #'str))
            (identifier? #'type))
       ;; A literal string: do the conversion at expansion time.
       (let ((bv (string->uuid (syntax->datum #'str)
                               (syntax->datum #'type))))
         (unless bv
           (syntax-violation 'uuid "invalid UUID" s))
         #`(make-uuid 'type #,(datum->syntax s bv))))
      ((_ str)
       (string? (syntax->datum #'str))
       #'(uuid str 'dce))
      ((_ str)
       #'(let ((bv (string->uuid str 'dce)))
           (and bv (make-uuid 'dce bv))))
      ((_ str type)
       #'(let ((bv (string->uuid str type)))
           (and bv (make-uuid type bv)))))))

(define uuid->string
  ;; Convert the given bytevector or UUID object, to the corresponding UUID
  ;; string representation.
  (match-lambda*
    (((? bytevector? bv))
     (uuid->string bv 'dce))
    (((? bytevector? bv) type)
     (match (vhash-assq type %uuid-printers)
       (#f #f)
       ((_ . (? procedure? unparse)) (unparse bv))))
    (((? uuid? uuid))
     (uuid->string (uuid-bytevector uuid) (uuid-type uuid)))))

(define uuid=?
  ;; Return true if A is equal to B, comparing only the actual bits.
  (match-lambda*
    (((? bytevector? a) (? bytevector? b))
     (bytevector=? a b))
    (((? uuid? a) (? bytevector? b))
     (bytevector=? (uuid-bytevector a) b))
    (((? uuid? a) (? uuid? b))
     (bytevector=? (uuid-bytevector a) (uuid-bytevector b)))
    (((or (? uuid? a) (? bytevector? a)) (or (? uuid? b) (? bytevector? b)))
     (uuid=? b a))))

debug log:

solving 8f967387ad ...
found 8f967387ad in https://git.savannah.gnu.org/cgit/guix.git

(*) Git path names are given by the tree(s) the blob belongs to.
    Blobs themselves have no identifier aside from the hash of its contents.^

Code repositories for project(s) associated with this external index

	https://git.savannah.gnu.org/cgit/guix.git

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.