guix-kreyren/guix/scripts/home.scm
Ludovic Courtès 9ea6a18e99
guix home: Show "container" in '--help' output.
This is a followup to 094a2cfbe45c104d0da30ff9d975d052ca0c118c.

* guix/scripts/home.scm (show-help): Add "container".
2022-03-19 22:25:53 +01:00

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;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
;;; Copyright © 2021 Pierre Langlois <pierre.langlois@gmx.com>
;;; Copyright © 2021 Oleg Pykhalov <go.wigust@gmail.com>
;;; Copyright © 2022 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 home)
#:use-module (gnu packages admin)
#:use-module ((gnu services) #:hide (delete))
#:use-module (gnu packages)
#:autoload (gnu packages base) (coreutils)
#:autoload (gnu packages bash) (bash)
#:autoload (gnu packages gnupg) (guile-gcrypt)
#:autoload (gnu packages shells) (fish gash zsh)
#:use-module (gnu home)
#:use-module (gnu home services)
#:autoload (gnu home services shepherd) (home-shepherd-service-type
home-shepherd-configuration-services
shepherd-service-requirement)
#:autoload (guix modules) (source-module-closure)
#:autoload (gnu build linux-container) (call-with-container %namespaces)
#:autoload (gnu system linux-container) (eval/container)
#:autoload (gnu system file-systems) (file-system-mapping
file-system-mapping-source
file-system-mapping->bind-mount
specification->file-system-mapping
%network-file-mappings)
#:autoload (guix self) (make-config.scm)
#:use-module (guix channels)
#:use-module (guix derivations)
#:use-module (guix ui)
#:use-module (guix grafts)
#:use-module (guix packages)
#:use-module (guix profiles)
#:use-module (guix store)
#:use-module (guix utils)
#:autoload (guix graph) (lookup-backend export-graph)
#:use-module (guix scripts)
#:use-module (guix scripts package)
#:use-module (guix scripts build)
#:autoload (guix scripts system search) (service-type->recutils)
#:use-module (guix scripts system reconfigure)
#:autoload (guix scripts pull) (channel-commit-hyperlink)
#:autoload (guix scripts system) (service-node-type
shepherd-service-node-type)
#:autoload (guix scripts home import) (import-manifest)
#:use-module ((guix status) #:select (with-status-verbosity))
#:use-module ((guix build utils) #:select (mkdir-p))
#:use-module (guix gexp)
#:use-module (guix monads)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-35)
#:use-module (srfi srfi-37)
#:use-module (srfi srfi-71)
#:use-module (ice-9 match)
#:export (guix-home))
;;;
;;; Options.
;;;
(define %user-module
(make-user-module '((gnu home))))
(define %guix-home
(string-append %profile-directory "/guix-home"))
(define (show-help)
(display (G_ "Usage: guix home [OPTION ...] ACTION [ARG ...] [FILE]
Build the home environment declared in FILE according to ACTION.
Some ACTIONS support additional ARGS.\n"))
(newline)
(display (G_ "The valid values for ACTION are:\n"))
(newline)
(display (G_ "\
search search for existing service types\n"))
(display (G_ "
container run the home environment configuration in a container\n"))
(display (G_ "\
reconfigure switch to a new home environment configuration\n"))
(display (G_ "\
roll-back switch to the previous home environment configuration\n"))
(display (G_ "\
describe describe the current home environment\n"))
(display (G_ "\
list-generations list the home environment generations\n"))
(display (G_ "\
switch-generation switch to an existing home environment configuration\n"))
(display (G_ "\
delete-generations delete old home environment generations\n"))
(display (G_ "\
build build the home environment without installing anything\n"))
(display (G_ "\
import generates a home environment definition from dotfiles\n"))
(display (G_ "\
extension-graph emit the service extension graph\n"))
(display (G_ "\
shepherd-graph emit the graph of shepherd services\n"))
(show-build-options-help)
(display (G_ "
-e, --expression=EXPR consider the home-environment EXPR evaluates to
instead of reading FILE, when applicable"))
(display (G_ "
--allow-downgrades for 'reconfigure', allow downgrades to earlier
channel revisions"))
(newline)
(display (G_ "
-N, --network allow containers to access the network"))
(display (G_ "
--share=SPEC for containers, share writable host file system
according to SPEC"))
(display (G_ "
--expose=SPEC for containers, expose read-only host file system
according to SPEC"))
(newline)
(display (G_ "
-v, --verbosity=LEVEL use the given verbosity LEVEL"))
(display (G_ "
--graph-backend=BACKEND
use BACKEND for 'extension-graph' and 'shepherd-graph'"))
(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 (verbosity-level opts)
"Return the verbosity level based on OPTS, the alist of parsed options."
(or (assoc-ref opts 'verbosity)
(if (eq? (assoc-ref opts 'action) 'build)
3 1)))
(define %options
;; Specification of the command-line options.
(cons* (option '(#\h "help") #f #f
(lambda args
(show-help)
(exit 0)))
(option '(#\n "dry-run") #f #f
(lambda (opt name arg result)
(alist-cons 'dry-run? #t result)))
(option '(#\V "version") #f #f
(lambda args
(show-version-and-exit "guix show")))
(option '(#\v "verbosity") #t #f
(lambda (opt name arg result)
(let ((level (string->number* arg)))
(alist-cons 'verbosity level
(alist-delete 'verbosity result)))))
(option '(#\e "expression") #t #f
(lambda (opt name arg result)
(alist-cons 'expression arg result)))
(option '("allow-downgrades") #f #f
(lambda (opt name arg result)
(alist-cons 'validate-reconfigure
warn-about-backward-reconfigure
result)))
(option '("graph-backend") #t #f
(lambda (opt name arg result)
(alist-cons 'graph-backend arg result)))
;; Container options.
(option '(#\N "network") #f #f
(lambda (opt name arg result)
(alist-cons 'network? #t result)))
(option '("share") #t #f
(lambda (opt name arg result)
(alist-cons 'file-system-mapping
(specification->file-system-mapping arg #t)
result)))
(option '("expose") #t #f
(lambda (opt name arg result)
(alist-cons 'file-system-mapping
(specification->file-system-mapping arg #f)
result)))
%standard-build-options))
(define %default-options
`((graft? . #t)
(substitutes? . #t)
(offload? . #t)
(print-build-trace? . #t)
(print-extended-build-trace? . #t)
(multiplexed-build-output? . #t)
(verbosity . #f) ;default
(debug . 0)
(validate-reconfigure . ,ensure-forward-reconfigure)
(graph-backend . "graphviz")))
;;;
;;; Container.
;;;
(define not-config?
;; Select (guix …) and (gnu …) modules, except (guix config).
(match-lambda
(('guix 'config) #f)
(('guix _ ...) #t)
(('gnu _ ...) #t)
(_ #f)))
(define (user-shell)
(match (and=> (or (getenv "SHELL")
(passwd:shell (getpwuid (getuid))))
basename)
("zsh" (file-append zsh "/bin/zsh"))
("fish" (file-append fish "/bin/fish"))
("gash" (file-append gash "/bin/gash"))
(_ (file-append bash "/bin/bash"))))
(define %default-system-profile
;; The "system" profile available when running 'guix home container'. The
;; activation script currently expects to run "env -0" (XXX), so provide
;; Coreutils by default.
(delay (profile
(name "home-system-profile")
(content (packages->manifest (list coreutils))))))
(define* (spawn-home-container home
#:key
network?
(command '())
(mappings '())
(system-profile
(force %default-system-profile)))
"Spawn a login shell within a container running HOME, a home environment.
When COMMAND is a non-empty list, execute it in the container and exit
immediately. Return the exit status of the process in the container."
(define passwd (getpwuid (getuid)))
(define home-directory (or (getenv "HOME") (passwd:dir passwd)))
(define host (gethostname))
(define uid 1000)
(define gid 1000)
(define user-name (passwd:name passwd))
(define user-real-name (passwd:gecos passwd))
(define (optional-mapping mapping)
(and (file-exists? (file-system-mapping-source mapping))
mapping))
(define network-mappings
(if network?
(filter-map optional-mapping %network-file-mappings)
'()))
(eval/container
(with-extensions (list guile-gcrypt)
(with-imported-modules `(((guix config) => ,(make-config.scm))
,@(source-module-closure
'((gnu build accounts)
(guix profiles)
(guix build utils)
(guix build syscalls))
#:select? not-config?))
#~(begin
(use-modules (guix build utils)
(gnu build accounts)
((guix build syscalls)
#:select (set-network-interface-up)))
(define shell
#$(user-shell))
(define term
#$(getenv "TERM"))
(define passwd
(password-entry
(name #$user-name)
(real-name #$user-real-name)
(uid #$uid) (gid #$gid) (shell shell)
(directory #$home-directory)))
(define groups
(list (group-entry (name "users") (gid #$gid))
(group-entry (gid 65534) ;the overflow GID
(name "overflow"))))
;; (guix profiles) loads (guix utils), which calls 'getpw' from the
;; top level. Thus, arrange so that it's loaded after /etc/passwd
;; has been created.
(module-autoload! (current-module)
'(guix profiles) '(load-profile))
;; Create /etc/passwd for applications that need it, such as mcron.
(mkdir-p "/etc")
(write-passwd (list passwd))
(write-group groups)
(unless #$network?
;; When isolated from the network, provide a minimal /etc/hosts
;; to resolve "localhost".
(call-with-output-file "/etc/hosts"
(lambda (port)
(display "127.0.0.1 localhost\n" port)
(chmod port #o444))))
;; Set PATH for things that the activation script might expect, such
;; as "env".
(load-profile #$system-profile)
(mkdir-p #$home-directory)
(setenv "HOME" #$home-directory)
(setenv "GUIX_NEW_HOME" #$home)
(primitive-load (string-append #$home "/activate"))
(setenv "GUIX_NEW_HOME" #f)
(when term
;; Preserve TERM for proper interactive use.
(setenv "TERM" term))
(chdir #$home-directory)
;; Invoke SHELL with argv[0] starting with "-": that's how shells
;; figure out that they are login shells!
(execl shell (string-append "-" (basename shell))
#$@(match command
(() #~())
((_ ...)
#~("-c" #$(string-join command))))))))
#:namespaces (if network?
(delq 'net %namespaces) ; share host network
%namespaces)
#:mappings (append network-mappings mappings)
#:guest-uid uid
#:guest-gid gid))
;;;
;;; Actions.
;;;
(define* (export-extension-graph home port
#:key (backend (lookup-backend "graphviz")))
"Export the service extension graph of HOME to PORT using BACKEND."
(let* ((services (home-environment-services home))
(home (find (lambda (service)
(eq? (service-kind service) home-service-type))
services)))
(export-graph (list home) port
#:backend backend
#:node-type (service-node-type services)
#:reverse-edges? #t)))
(define* (export-shepherd-graph home port
#:key (backend (lookup-backend "graphviz")))
"Export the graph of shepherd services of HOME to PORT using BACKEND."
(let* ((services (home-environment-services home))
(root (fold-services services
#:target-type home-shepherd-service-type))
;; Get the list of <shepherd-service>.
(shepherds (home-shepherd-configuration-services
(service-value root)))
(sinks (filter (lambda (service)
(null? (shepherd-service-requirement service)))
shepherds)))
(export-graph sinks port
#:backend backend
#:node-type (shepherd-service-node-type shepherds)
#:reverse-edges? #t)))
(define* (perform-action action he
#:key
dry-run?
derivations-only?
use-substitutes?
(graph-backend "graphviz")
(validate-reconfigure ensure-forward-reconfigure)
;; Container options.
(file-system-mappings '())
(container-command '())
network?)
"Perform ACTION for home environment. "
(define println
(cut format #t "~a~%" <>))
(when (eq? action 'reconfigure)
(check-forward-update validate-reconfigure
#:current-channels (home-provenance %guix-home)))
(case action
((extension-graph)
(export-extension-graph he (current-output-port)
#:backend (lookup-backend graph-backend)))
((shepherd-graph)
(export-shepherd-graph he (current-output-port)
#:backend (lookup-backend graph-backend)))
(else
(mlet* %store-monad
((he-drv (home-environment-derivation he))
(drvs (mapm/accumulate-builds lower-object (list he-drv)))
(% (if derivations-only?
(return
(for-each (compose println derivation-file-name) drvs))
(built-derivations drvs)))
(he-out-path -> (derivation->output-path he-drv)))
(if (or dry-run? derivations-only?)
(return #f)
(case action
((reconfigure)
(let* ((number (generation-number %guix-home))
(generation (generation-file-name
%guix-home (+ 1 number))))
(switch-symlinks generation he-out-path)
(switch-symlinks %guix-home generation)
(setenv "GUIX_NEW_HOME" he-out-path)
(primitive-load (string-append he-out-path "/activate"))
(setenv "GUIX_NEW_HOME" #f)
(return he-out-path)))
((container)
(mlet %store-monad ((status (spawn-home-container
he
#:network? network?
#:mappings file-system-mappings
#:command
container-command)))
(match (status:exit-val status)
(0 (return #t))
((? integer? n) (return (exit n)))
(#f
(if (status:term-sig status)
(leave (G_ "process terminated with signal ~a~%")
(status:term-sig status))
(leave (G_ "process stopped with signal ~a~%")
(status:stop-sig status)))))))
(else
(for-each (compose println derivation->output-path) drvs)
(return he-out-path))))))))
(define (process-action action args opts)
"Process ACTION, a sub-command, with the arguments are listed in ARGS.
ACTION must be one of the sub-commands that takes a home environment
declaration as an argument (a file name.) OPTS is the raw alist of options
resulting from command-line parsing."
(define (ensure-home-environment file-or-exp obj)
(ensure-profile-directory)
(unless (home-environment? obj)
(leave (G_ "'~a' does not return a home environment ~%")
file-or-exp))
obj)
(let* ((file (match args
(() #f)
((x . _) x)))
(expr (assoc-ref opts 'expression))
(system (assoc-ref opts 'system))
(transform (lambda (obj)
(home-environment-with-provenance obj file)))
(home-environment
(transform
(ensure-home-environment
(or file expr)
(cond
((and expr file)
(leave
(G_ "both file and expression cannot be specified~%")))
(expr
(read/eval expr))
(file
(load* file %user-module
#:on-error (assoc-ref opts 'on-error)))
(else
(leave (G_ "no configuration specified~%")))))))
(mappings (filter-map (match-lambda
(('file-system-mapping . mapping) mapping)
(_ #f))
opts))
(dry? (assoc-ref opts 'dry-run?)))
(with-store store
(set-build-options-from-command-line store opts)
(with-build-handler (build-notifier #:use-substitutes?
(assoc-ref opts 'substitutes?)
#:verbosity
(verbosity-level opts)
#:dry-run?
(assoc-ref opts 'dry-run?))
(run-with-store store
(mbegin %store-monad
(set-guile-for-build (default-guile))
(perform-action action home-environment
#:dry-run? dry?
#:derivations-only? (assoc-ref opts 'derivations-only?)
#:use-substitutes? (assoc-ref opts 'substitutes?)
#:validate-reconfigure
(assoc-ref opts 'validate-reconfigure)
#:graph-backend
(assoc-ref opts 'graph-backend)
#:network? (assoc-ref opts 'network?)
#:file-system-mappings mappings
#:container-command
(or (assoc-ref opts 'container-command) '()))))))
(warn-about-disk-space)))
(define (process-command command args opts)
"Process COMMAND, one of the 'guix home' sub-commands. ARGS is its
argument list and OPTS is the option alist."
(define-syntax-rule (with-store* store exp ...)
(with-store store
(set-build-options-from-command-line store opts)
exp ...))
(case command
;; The following commands do not need to use the store, and they do not need
;; an home environment file.
((search)
(apply search args))
((import)
(let* ((profiles (delete-duplicates
(match (filter-map (match-lambda
(('profile . p) p)
(_ #f))
opts)
(() (list %current-profile))
(lst (reverse lst)))))
(manifest (concatenate-manifests
(map profile-manifest profiles)))
(destination (match args
((destination) destination)
(_ (leave (G_ "wrong number of arguments~%"))))))
(unless (file-exists? destination)
(mkdir-p destination))
(call-with-output-file
(string-append destination "/home-configuration.scm")
(cut import-manifest manifest destination <>))
(info (G_ "'~a' populated with all the Home configuration files~%")
destination)
(display-hint (format #f (G_ "\
Run @command{guix home reconfigure ~a/home-configuration.scm} to effectively
deploy the home environment described by these files.\n")
destination))))
((describe)
(match (generation-number %guix-home)
(0
(leave (G_ "no home environment generation, nothing to describe~%")))
(generation
(display-home-environment-generation generation))))
((list-generations)
(let ((pattern (match args
(() #f)
((pattern) pattern)
(x (leave (G_ "wrong number of arguments~%"))))))
(list-generations pattern)))
((switch-generation)
(let ((pattern (match args
((pattern) pattern)
(x (leave (G_ "wrong number of arguments~%"))))))
(with-store* store
(switch-to-home-environment-generation store pattern))))
((roll-back)
(let ((pattern (match args
(() "")
(x (leave (G_ "wrong number of arguments~%"))))))
(with-store* store
(roll-back-home-environment store))))
((delete-generations)
(let ((pattern (match args
(() #f)
((pattern) pattern)
(x (leave (G_ "wrong number of arguments~%"))))))
(with-store*
store
(delete-matching-generations store %guix-home pattern))))
(else (process-action command args opts))))
(define-command (guix-home . args)
(synopsis "build and deploy home environments")
(define (parse-sub-command arg result)
;; Parse sub-command ARG and augment RESULT accordingly.
(if (assoc-ref result 'action)
(alist-cons 'argument arg result)
(let ((action (string->symbol arg)))
(case action
((build
reconfigure
extension-graph shepherd-graph
list-generations describe
delete-generations roll-back
switch-generation search
import container)
(alist-cons 'action action result))
(else (leave (G_ "~a: unknown action~%") action))))))
(define (match-pair car)
;; Return a procedure that matches a pair with CAR.
(match-lambda
((head . tail)
(and (eq? car head) tail))
(_ #f)))
(define (option-arguments opts)
;; Extract the plain arguments from OPTS.
(let* ((args (reverse (filter-map (match-pair 'argument) opts)))
(count (length args))
(action (assoc-ref opts 'action))
(expr (assoc-ref opts 'expression)))
(define (fail)
(leave (G_ "wrong number of arguments for action '~a'~%")
action))
(unless action
(format (current-error-port)
(G_ "guix home: missing command name~%"))
(format (current-error-port)
(G_ "Try 'guix home --help' for more information.~%"))
(exit 1))
(case action
((build reconfigure)
(unless (or (= count 1)
(and expr (= count 0)))
(fail)))
((init)
(unless (= count 2)
(fail))))
args))
(define (parse-args args)
;; Parse the list of command line arguments ARGS.
;; The '--' token is used to separate the command to run from the rest of
;; the operands.
(let* ((args rest (break (cut string=? "--" <>) args))
(opts (parse-command-line args %options (list %default-options)
#:argument-handler
parse-sub-command)))
(match rest
(() opts)
(("--") opts)
(("--" command ...)
(match (assoc-ref opts 'action)
('container
(alist-cons 'container-command command opts))
(_
(leave (G_ "~a: extraneous command~%")
(string-join command))))))))
(with-error-handling
(let* ((opts (parse-args args))
(args (option-arguments opts))
(command (assoc-ref opts 'action)))
(parameterize ((%graft? (assoc-ref opts 'graft?)))
(with-status-verbosity (verbosity-level opts)
(process-command command args opts))))))
;;;
;;; Searching.
;;;
(define service-type-name*
(compose symbol->string service-type-name))
(define (service-type-description-string type)
"Return the rendered and localised description of TYPE, a service type."
(and=> (service-type-description type)
(compose texi->plain-text P_)))
(define %service-type-metrics
;; Metrics used to estimate the relevance of a search result.
`((,service-type-name* . 3)
(,service-type-description-string . 2)
(,(lambda (type)
(match (and=> (service-type-location type) location-file)
((? string? file)
(basename file ".scm"))
(#f
"")))
. 1)))
(define (find-service-types regexps)
"Return a list of service type/score pairs: service types whose name or
description matches REGEXPS sorted by relevance, and their score."
(let ((matches (fold-home-service-types
(lambda (type result)
(match (relevance type regexps
%service-type-metrics)
((? zero?)
result)
(score
(cons (cons type score) result))))
'())))
(sort matches
(lambda (m1 m2)
(match m1
((type1 . score1)
(match m2
((type2 . score2)
(if (= score1 score2)
(string>? (service-type-name* type1)
(service-type-name* type2))
(> score1 score2))))))))))
(define (search . args)
(with-error-handling
(let* ((regexps (map (cut make-regexp* <> regexp/icase) args))
(matches (find-service-types regexps)))
(leave-on-EPIPE
(display-search-results matches (current-output-port)
#:print service-type->recutils
#:command "guix home search")))))
;;;
;;; Generations.
;;;
(define* (display-home-environment-generation
number
#:optional (profile %guix-home))
"Display a summary of home-environment generation NUMBER in a
human-readable format."
(define (display-channel channel)
(format #t " ~a:~%" (channel-name channel))
(format #t (G_ " repository URL: ~a~%") (channel-url channel))
(when (channel-branch channel)
(format #t (G_ " branch: ~a~%") (channel-branch channel)))
(format #t (G_ " commit: ~a~%")
(if (supports-hyperlinks?)
(channel-commit-hyperlink channel)
(channel-commit channel))))
(unless (zero? number)
(let* ((generation (generation-file-name profile number)))
(define-values (channels config-file)
;; The function will work for home environments too, we just
;; need to keep provenance file.
(system-provenance generation))
(display-generation profile number)
(format #t (G_ " file name: ~a~%") generation)
(format #t (G_ " canonical file name: ~a~%") (readlink* generation))
;; TRANSLATORS: Please preserve the two-space indentation.
(unless (null? channels)
;; TRANSLATORS: Here "channel" is the same terminology as used in
;; "guix describe" and "guix pull --channels".
(format #t (G_ " channels:~%"))
(for-each display-channel channels))
(when config-file
(format #t (G_ " configuration file: ~a~%")
(if (supports-hyperlinks?)
(file-hyperlink config-file)
config-file))))))
(define* (list-generations pattern #:optional (profile %guix-home))
"Display in a human-readable format all the home environment
generations matching PATTERN, a string. When PATTERN is #f, display
all the home environment generations."
(cond ((not (file-exists? profile)) ; XXX: race condition
(raise (condition (&profile-not-found-error
(profile profile)))))
((not pattern)
(for-each display-home-environment-generation (profile-generations profile)))
((matching-generations pattern profile)
=>
(lambda (numbers)
(if (null-list? numbers)
(exit 1)
(leave-on-EPIPE
(for-each display-home-environment-generation numbers)))))))
;;;
;;; Switch generations.
;;;
;; TODO: Make it public in (guix scripts system)
(define-syntax-rule (unless-file-not-found exp)
(catch 'system-error
(lambda ()
exp)
(lambda args
(if (= ENOENT (system-error-errno args))
#f
(apply throw args)))))
(define (switch-to-home-environment-generation store spec)
"Switch the home-environment profile to the generation specified by
SPEC. STORE is an open connection to the store."
(let* ((number (relative-generation-spec->number %guix-home spec))
(generation (generation-file-name %guix-home number))
(activate (string-append generation "/activate")))
(if number
(begin
(setenv "GUIX_NEW_HOME" (readlink generation))
(switch-to-generation* %guix-home number)
(unless-file-not-found (primitive-load activate))
(setenv "GUIX_NEW_HOME" #f))
(leave (G_ "cannot switch to home environment generation '~a'~%") spec))))
;;;
;;; Roll-back.
;;;
(define (roll-back-home-environment store)
"Roll back the home-environment profile to its previous generation.
STORE is an open connection to the store."
(switch-to-home-environment-generation store "-1"))