guix package: Export generation procedures.

* guix/scripts/package.scm: Export 'roll-back', 'delete-generation',
  'delete-generations'.
  (link-to-empty-profile, roll-back): Add 'store' argument.
  (delete-generations): New procedure.
  (guix-package): Adjust accordingly.
  [delete-generation]: Move to the top level.  Add 'store' and 'profile'
  arguments.
  [display-and-delete]: Move to 'delete-generation'.
This commit is contained in:
Alex Kost 2014-10-04 20:45:35 +04:00
parent 881c3f0163
commit b72a312c30

View file

@ -2,6 +2,7 @@
;;; Copyright © 2012, 2013, 2014 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2013 Nikita Karetnikov <nikita@karetnikov.org>
;;; Copyright © 2013 Mark H Weaver <mhw@netris.org>
;;; Copyright © 2014 Alex Kost <alezost@gmail.com>
;;;
;;; This file is part of GNU Guix.
;;;
@ -43,6 +44,9 @@ (define-module (guix scripts package)
#:use-module (gnu packages guile)
#:use-module ((gnu packages bootstrap) #:select (%bootstrap-guile))
#:export (specification->package+output
roll-back
delete-generation
delete-generations
guix-package))
(define %store
@ -80,12 +84,12 @@ (define (canonicalize-profile profile)
%current-profile
profile))
(define (link-to-empty-profile generation)
(define (link-to-empty-profile store generation)
"Link GENERATION, a string, to the empty profile."
(let* ((drv (run-with-store (%store)
(let* ((drv (run-with-store store
(profile-derivation (manifest '()))))
(prof (derivation->output-path drv "out")))
(when (not (build-derivations (%store) (list drv)))
(when (not (build-derivations store (list drv)))
(leave (_ "failed to build the empty profile~%")))
(switch-symlinks generation prof)))
@ -99,7 +103,7 @@ (define (switch-to-previous-generation profile)
number previous-number)
(switch-symlinks profile previous-generation)))
(define (roll-back profile)
(define (roll-back store profile)
"Roll back to the previous generation of PROFILE."
(let* ((number (generation-number profile))
(previous-number (previous-generation-number profile number))
@ -112,11 +116,39 @@ (define (roll-back profile)
(_ "nothing to do: already at the empty profile~%")))
((or (zero? previous-number) ; going to emptiness
(not (file-exists? previous-generation)))
(link-to-empty-profile previous-generation)
(link-to-empty-profile store previous-generation)
(switch-to-previous-generation profile))
(else
(switch-to-previous-generation profile))))) ; anything else
(define (delete-generation store profile number)
"Delete generation with NUMBER from PROFILE."
(define (display-and-delete)
(let ((generation (generation-file-name profile number)))
(format #t (_ "deleting ~a~%") generation)
(delete-file generation)))
(let* ((current-number (generation-number profile))
(previous-number (previous-generation-number profile number))
(previous-generation (generation-file-name profile previous-number)))
(cond ((zero? number)) ; do not delete generation 0
((and (= number current-number)
(not (file-exists? previous-generation)))
(link-to-empty-profile store previous-generation)
(switch-to-previous-generation profile)
(display-and-delete))
((= number current-number)
(roll-back store profile)
(display-and-delete))
(else
(display-and-delete)))))
(define (delete-generations store profile generations)
"Delete GENERATIONS from PROFILE.
GENERATIONS is a list of generation numbers."
(for-each (cut delete-generation store profile <>)
generations))
(define* (matching-generations str #:optional (profile %current-profile)
#:key (duration-relation <=))
"Return the list of available generations matching a pattern in STR. See
@ -680,32 +712,10 @@ (define profile (assoc-ref opts 'profile))
(define current-generation-number
(generation-number profile))
(define (display-and-delete number)
(let ((generation (generation-file-name profile number)))
(unless (zero? number)
(format #t (_ "deleting ~a~%") generation)
(delete-file generation))))
(define (delete-generation number)
(let* ((previous-number (previous-generation-number profile number))
(previous-generation
(generation-file-name profile previous-number)))
(cond ((zero? number)) ; do not delete generation 0
((and (= number current-generation-number)
(not (file-exists? previous-generation)))
(link-to-empty-profile previous-generation)
(switch-to-previous-generation profile)
(display-and-delete number))
((= number current-generation-number)
(roll-back profile)
(display-and-delete number))
(else
(display-and-delete number)))))
;; First roll back if asked to.
(cond ((and (assoc-ref opts 'roll-back?) (not dry-run?))
(begin
(roll-back profile)
(roll-back (%store) profile)
(process-actions (alist-delete 'roll-back? opts))))
((and (assoc-ref opts 'delete-generations)
(not dry-run?))
@ -716,9 +726,10 @@ (define (delete-generation number)
(leave (_ "profile '~a' does not exist~%")
profile))
((string-null? pattern)
(for-each display-and-delete
(delete current-generation-number
(profile-generations profile))))
(delete-generations
(%store) profile
(delete current-generation-number
(profile-generations profile))))
;; Do not delete the zeroth generation.
((equal? 0 (string->number pattern))
(exit 0))
@ -731,7 +742,7 @@ (define (delete-generation number)
(lambda (numbers)
(if (null-list? numbers)
(exit 1)
(for-each delete-generation numbers))))
(delete-generations (%store) profile numbers))))
(else
(leave (_ "invalid syntax: ~a~%")
pattern)))