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;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2019 David Thompson <davet@gnu.org>
;;; Copyright © 2019 Jakob L. Kreuze <zerodaysfordays@sdf.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 (gnu machine)
  #:use-module (gnu system)
  #:use-module (guix derivations)
  #:use-module (guix monads)
  #:use-module (guix records)
  #:use-module (guix store)
  #:use-module ((guix diagnostics) #:select (source-properties->location))
  #:use-module (srfi srfi-35)
  #:export (environment-type
            environment-type?
            environment-type-name
            environment-type-description
            environment-type-location

            machine
            machine?

            machine-operating-system
            machine-environment
            machine-configuration
            machine-display-name

            deploy-machine
            roll-back-machine
            machine-remote-eval

            &deploy-error
            deploy-error?
            deploy-error-should-roll-back
            deploy-error-captured-args))

;;; Commentary:
;;;
;;; This module provides the types used to declare individual machines in a
;;; heterogeneous Guix deployment. The interface allows users of specify system
;;; configurations and the means by which resources should be provisioned on a
;;; per-host basis.
;;;
;;; Code:


;;;
;;; Declarations for resources that can be provisioned.
;;;

(define-record-type* <environment-type> environment-type
  make-environment-type
  environment-type?

  ;; Interface to the environment type's deployment code. Each procedure
  ;; should take the same arguments as the top-level procedure of this file
  ;; that shares the same name. For example, 'machine-remote-eval' should be
  ;; of the form '(machine-remote-eval machine exp)'.
  (machine-remote-eval environment-type-machine-remote-eval) ; procedure
  (deploy-machine      environment-type-deploy-machine)      ; procedure
  (roll-back-machine   environment-type-roll-back-machine)   ; procedure

  ;; Metadata.
  (name        environment-type-name)       ; symbol
  (description environment-type-description ; string
               (default #f))
  (location    environment-type-location    ; <location>
               (default (and=> (current-source-location)
                               source-properties->location))
               (innate)))


;;;
;;; Declarations for machines in a deployment.
;;;

(define-record-type* <machine> machine make-machine
  machine?
  (operating-system %machine-operating-system); <operating-system>
  (environment      machine-environment)      ; symbol
  (configuration    machine-configuration     ; configuration object
                    (default #f)))            ; specific to environment

(define (machine-operating-system machine)
  "Return the operating system of MACHINE."
  (operating-system-with-provenance
   (%machine-operating-system machine)))

(define (machine-display-name machine)
  "Return the host-name identifying MACHINE."
  (operating-system-host-name (machine-operating-system machine)))

(define (machine-remote-eval machine exp)
  "Evaluate EXP, a gexp, on MACHINE. Ensure that all the elements EXP refers to
are built and deployed to MACHINE beforehand."
  (let ((environment (machine-environment machine)))
    ((environment-type-machine-remote-eval environment) machine exp)))

(define (deploy-machine machine)
  "Monadic procedure transferring the new system's OS closure to the remote
MACHINE, activating it on MACHINE and switching MACHINE to the new generation."
  (let ((environment (machine-environment machine)))
    ((environment-type-deploy-machine environment) machine)))

(define (roll-back-machine machine)
  "Monadic procedure rolling back to the previous system generation on
MACHINE. Return the number of the generation that was current before switching
and the new generation number."
  (let ((environment (machine-environment machine)))
    ((environment-type-roll-back-machine environment) machine)))


;;;
;;; Error types.
;;;

(define-condition-type &deploy-error &error
  deploy-error?
  (should-roll-back deploy-error-should-roll-back)
  (captured-args deploy-error-captured-args))
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;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2017, 2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
;;; Copyright © 2018, 2019 Clément Lassieur <clement@lassieur.org>
;;; Copyright © 2020 Julien Lepiller <julien@lepiller.eu>
;;; Copyright © 2020 Mathieu Othacehe <othacehe@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 (gnu ci)
  #:use-module (guix config)
  #:use-module (guix store)
  #:use-module (guix grafts)
  #:use-module (guix profiles)
  #:use-module (guix packages)
  #:use-module (guix channels)
  #:use-module (guix config)
  #:use-module (guix derivations)
  #:use-module (guix build-system)
  #:use-module (guix monads)
  #:use-module (guix gexp)
  #:use-module (guix ui)
  #:use-module ((guix licenses)
                #:select (gpl3+ license? license-name))
  #:use-module ((guix utils) #:select (%current-system))
  #:use-module ((guix scripts system) #:select (read-operating-system))
  #:use-module ((guix scripts pack)
                #:select (lookup-compressor self-contained-tarball))
  #:use-module (gnu bootloader)
  #:use-module (gnu bootloader u-boot)
  #:use-module (gnu image)
  #:use-module (gnu packages)
  #:use-module (gnu packages gcc)
  #:use-module (gnu packages base)
  #:use-module (gnu packages gawk)
  #:use-module (gnu packages guile)
  #:use-module (gnu packages gettext)
  #:use-module (gnu packages compression)
  #:use-module (gnu packages multiprecision)
  #:use-module (gnu packages make-bootstrap)
  #:use-module (gnu packages package-management)
  #:use-module (gnu system)
  #:use-module (gnu system image)
  #:use-module (gnu system vm)
  #:use-module (gnu system install)
  #:use-module (gnu system images hurd)
  #:use-module (gnu system images novena)
  #:use-module (gnu system images pine64)
  #:use-module (gnu system images pinebook-pro)
  #:use-module (gnu tests)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 match)
  #:export (%cross-targets
            channel-source->package
            hydra-jobs))

;;; Commentary:
;;;
;;; This file defines build jobs for the Hydra and Cuirass continuation
;;; integration tools.
;;;
;;; Code:

(define* (package->alist store package system
                         #:optional (package-derivation package-derivation))
  "Convert PACKAGE to an alist suitable for Hydra."
  (parameterize ((%graft? #f))
    (let ((drv (package-derivation store package system
                                   #:graft? #f)))
      `((derivation . ,(derivation-file-name drv))
        (log . ,(log-file store (derivation-file-name drv)))
        (outputs . ,(filter-map (lambda (res)
                                  (match res
                                    ((name . path)
                                     `(,name . ,path))))
                                (derivation->output-paths drv)))
        (nix-name . ,(derivation-name drv))
        (system . ,(derivation-system drv))
        (description . ,(package-synopsis package))
        (long-description . ,(package-description package))

        ;; XXX: Hydra ignores licenses that are not a <license> structure or a
        ;; list thereof.
        (license . ,(let loop ((license (package-license package)))
                      (match license
                        ((? license?)
                         (license-name license))
                        ((lst ...)
                         (map loop license)))))

        (home-page . ,(package-home-page package))
        (maintainers . ("bug-guix@gnu.org"))
        (max-silent-time . ,(or (assoc-ref (package-properties package)
                                           'max-silent-time)
                                3600))              ;1 hour by default
        (timeout . ,(or (assoc-ref (package-properties package) 'timeout)
                        72000))))))                  ;20 hours by default

(define (package-job store job-name package system)
  "Return a job called JOB-NAME that builds PACKAGE on SYSTEM."
  (let ((job-name (symbol-append job-name (string->symbol ".")
                                 (string->symbol system))))
    `(,job-name . ,(cut package->alist store package system))))

(define (package-cross-job store job-name package target system)
  "Return a job called TARGET.JOB-NAME that cross-builds PACKAGE for TARGET on
SYSTEM."
  `(,(symbol-append (string->symbol target) (string->symbol ".") job-name
                    (string->symbol ".") (string->symbol system)) .
    ,(cute package->alist store package system
           (lambda* (store package system #:key graft?)
             (package-cross-derivation store package target system
                                       #:graft? graft?)))))

(define %core-packages
  ;; Note: Don't put the '-final' package variants because (1) that's
  ;; implicit, and (2) they cannot be cross-built (due to the explicit input
  ;; chain.)
  (list gcc-7 gcc-8 gcc-9 gcc-10 glibc binutils
        gmp mpfr mpc coreutils findutils diffutils patch sed grep
        gawk gnu-gettext hello guile-2.0 guile-2.2 zlib gzip xz
        %bootstrap-binaries-tarball
        %binutils-bootstrap-tarball
        (%glibc-bootstrap-tarball)
        %gcc-bootstrap-tarball
        %guile-bootstrap-tarball
        %bootstrap-tarballs))

(define (packages-to-cross-build target)
  "Return the list of packages to cross-build for TARGET."
  ;; Don't cross-build the bootstrap tarballs for MinGW.
  (if (string-contains target "mingw")
      (drop-right %core-packages 6)
      %core-packages))

(define %cross-targets
  '("mips64el-linux-gnu"
    "arm-linux-gnueabihf"
    "aarch64-linux-gnu"
    "powerpc-linux-gnu"
    "riscv64-linux-gnu"
    "i586-pc-gnu"                                 ;aka. GNU/Hurd
    "i686-w64-mingw32"
    "x86_64-w64-mingw32"))

(define (cross-jobs store system)
  "Return a list of cross-compilation jobs for SYSTEM."
  (define (from-32-to-64? target)
    ;; Return true if SYSTEM is 32-bit and TARGET is 64-bit.  This hack
    ;; prevents known-to-fail cross-builds from i686-linux or armhf-linux to
    ;; mips64el-linux-gnuabi64.
    (and (or (string-prefix? "i686-" system)
             (string-prefix? "i586-" system)
             (string-prefix? "armhf-" system))
         (string-contains target "64")))    ;x86_64, mips64el, aarch64, etc.

  (define (same? target)
    ;; Return true if SYSTEM and TARGET are the same thing.  This is so we
    ;; don't try to cross-compile to 'mips64el-linux-gnu' from
    ;; 'mips64el-linux'.
    (or (string-contains target system)
        (and (string-prefix? "armhf" system)    ;armhf-linux
             (string-prefix? "arm" target))))   ;arm-linux-gnueabihf

  (define (pointless? target)
    ;; Return #t if it makes no sense to cross-build to TARGET from SYSTEM.
    (match system
      ((or "x86_64-linux" "i686-linux")
       (if (string-contains target "mingw")
           (not (string=? "x86_64-linux" system))
           #f))
      (_
       ;; Don't try to cross-compile from non-Intel platforms: this isn't
       ;; very useful and these are often brittle configurations.
       #t)))

  (define (either proc1 proc2 proc3)
    (lambda (x)
      (or (proc1 x) (proc2 x) (proc3 x))))

  (append-map (lambda (target)
                (map (lambda (package)
                       (package-cross-job store (job-name package)
                                          package target system))
                     (packages-to-cross-build target)))
              (remove (either from-32-to-64? same? pointless?)
                      %cross-targets)))

;; Architectures that are able to build or cross-build Guix System images.
;; This does not mean that other architectures are not supported, only that
;; they are often not fast enough to support Guix System images building.
(define %guix-system-supported-systems
  '("x86_64-linux" "i686-linux"))

(define %guix-system-images
  (list hurd-barebones-qcow2-image
        pine64-barebones-raw-image
        pinebook-pro-barebones-raw-image
        novena-barebones-raw-image))

(define (hours hours)
  (* 3600 hours))

(define (image-jobs store system)
  "Return a list of jobs that build images for SYSTEM.  Those jobs are
expensive in storage and I/O operations, hence their periodicity is limited by
passing the PERIOD argument."
  (define (->alist drv)
    `((derivation . ,(derivation-file-name drv))
      (log . ,(log-file store (derivation-file-name drv)))
      (outputs . ,(filter-map (lambda (res)
                                (match res
                                  ((name . path)
                                   `(,name . ,path))))
                              (derivation->output-paths drv)))
      (nix-name . ,(derivation-name drv))
      (system . ,(derivation-system drv))
      (description . "Stand-alone image of the GNU system")
      (long-description . "This is a demo stand-alone image of the GNU
system.")
      (license . ,(license-name gpl3+))
      (period . ,(hours 48))
      (max-silent-time . 600)
      (timeout . 3600)
      (home-page . ,%guix-home-page-url)
      (maintainers . ("bug-guix@gnu.org"))))

  (define (->job name drv)
    (let ((name (symbol-append name (string->symbol ".")
                               (string->symbol system))))
      `(,name . ,(lambda ()
                   (parameterize ((%graft? #f))
                     (->alist drv))))))

  (define (build-image image)
    (run-with-store store
      (mbegin %store-monad
        (set-guile-for-build (default-guile))
        (lower-object (system-image image)))))

  (define MiB
    (expt 2 20))

  (if (member system %guix-system-supported-systems)
      `(,(->job 'usb-image
                (build-image
                 (image
                  (inherit efi-disk-image)
                  (operating-system installation-os))))
        ,(->job 'iso9660-image
                (build-image
                 (image
                  (inherit (image-with-label
                             iso9660-image
                             (string-append "GUIX_" system "_"
                                            (if (> (string-length %guix-version) 7)
                                                (substring %guix-version 0 7)
                                                %guix-version))))
                  (operating-system installation-os))))
        ;; Only cross-compile Guix System images from x86_64-linux for now.
        ,@(if (string=? system "x86_64-linux")
              (map (lambda (image)
                     (->job (image-name image) (build-image image)))
                   %guix-system-images)
              '()))
      '()))

(define channel-build-system
  ;; Build system used to "convert" a channel instance to a package.
  (let* ((build (lambda* (store name inputs
                                #:key source commit system
                                #:allow-other-keys)
                  (run-with-store store
                    ;; SOURCE can be a lowerable object such as <local-file>
                    ;; or a file name.  Adjust accordingly.
                    (mlet* %store-monad ((source (if (string? source)
                                                     (return source)
                                                     (lower-object source)))
                                         (instance
                                          -> (checkout->channel-instance
                                              source #:commit commit)))
                      (channel-instances->derivation (list instance)))
                    #:system system)))
         (lower (lambda* (name #:key system source commit
                               #:allow-other-keys)
                  (bag
                    (name name)
                    (system system)
                    (build build)
                    (arguments `(#:source ,source
                                 #:commit ,commit))))))
    (build-system (name 'channel)
                  (description "Turn a channel instance into a package.")
                  (lower lower))))

(define* (channel-source->package source #:key commit)
  "Return a package for the given channel SOURCE, a lowerable object."
  (package
    (inherit guix)
    (version (string-append (package-version guix) "+"))
    (build-system channel-build-system)
    (arguments `(#:source ,source
                 #:commit ,commit))
    (inputs '())
    (native-inputs '())
    (propagated-inputs '())))

(define* (system-test-jobs store system
                           #:key source commit)
  "Return a list of jobs for the system tests."
  (define (test->thunk test)
    (lambda ()
      (define drv
        (run-with-store store
          (mbegin %store-monad
            (set-current-system system)
            (set-grafting #f)
            (set-guile-for-build (default-guile))
            (system-test-value test))))

      ;; Those tests are extremely expensive in I/O operations and storage
      ;; size, use the "period" attribute to run them with a period of at
      ;; least 48 hours.
      `((derivation . ,(derivation-file-name drv))
        (log . ,(log-file store (derivation-file-name drv)))
        (outputs . ,(filter-map (lambda (res)
                                  (match res
                                    ((name . path)
                                     `(,name . ,path))))
                                (derivation->output-paths drv)))
        (nix-name . ,(derivation-name drv))
        (system . ,(derivation-system drv))
        (description . ,(format #f "Guix '~a' system test"
                                (system-test-name test)))
        (long-description . ,(system-test-description test))
        (license . ,(license-name gpl3+))
        (period . ,(hours 48))
        (max-silent-time . 600)
        (timeout . 3600)
        (home-page . ,%guix-home-page-url)
        (maintainers . ("bug-guix@gnu.org")))))

  (define (->job test)
    (let ((name (string->symbol
                 (string-append "test." (system-test-name test)
                                "." system))))
      (cons name (test->thunk test))))

  (if (member system %guix-system-supported-systems)
      ;; Override the value of 'current-guix' used by system tests.  Using a
      ;; channel instance makes tests that rely on 'current-guix' less
      ;; expensive.  It also makes sure we get a valid Guix package when this
      ;; code is not running from a checkout.
      (parameterize ((current-guix-package
                      (channel-source->package source #:commit commit)))
        (map ->job (all-system-tests)))
      '()))

(define (tarball-jobs store system)
  "Return Hydra jobs to build the self-contained Guix binary tarball."
  (define (->alist drv)
    `((derivation . ,(derivation-file-name drv))
      (log . ,(log-file store (derivation-file-name drv)))
      (outputs . ,(filter-map (lambda (res)
                                (match res
                                  ((name . path)
                                   `(,name . ,path))))
                              (derivation->output-paths drv)))
      (nix-name . ,(derivation-name drv))
      (system . ,(derivation-system drv))
      (description . "Stand-alone binary Guix tarball")
      (long-description . "This is a tarball containing binaries of Guix and
all its dependencies, and ready to be installed on \"foreign\" distributions.")
      (license . ,(license-name gpl3+))
      (home-page . ,%guix-home-page-url)
      (maintainers . ("bug-guix@gnu.org"))
      (period . ,(hours 24))))

  (define (->job name drv)
    (let ((name (symbol-append name (string->symbol ".")
                               (string->symbol system))))
      `(,name . ,(lambda ()
                   (parameterize ((%graft? #f))
                     (->alist drv))))))

  ;; XXX: Add a job for the stable Guix?
  (list (->job 'binary-tarball
               (run-with-store store
                 (mbegin %store-monad
                   (set-guile-for-build (default-guile))
                   (>>= (profile-derivation (packages->manifest (list guix)))
                        (lambda (profile)
                          (self-contained-tarball "guix-binary" profile
                                                  #:localstatedir? #t
                                                  #:compressor
                                                  (lookup-compressor "xz")))))
                 #:system system))))

(define job-name
  ;; Return the name of a package's job.
  (compose string->symbol
           (cut package-full-name <> "-")))

(define package->job
  (let ((base-packages
         (delete-duplicates
          (append-map (match-lambda
                       ((_ package _ ...)
                        (match (package-transitive-inputs package)
                          (((_ inputs _ ...) ...)
                           inputs))))
                      (%final-inputs)))))
    (lambda (store package system)
      "Return a job for PACKAGE on SYSTEM, or #f if this combination is not
valid."
      (cond ((member package base-packages)
             (package-job store (symbol-append 'base. (job-name package))
                          package system))
            ((supported-package? package system)
             (let ((drv (package-derivation store package system
                                            #:graft? #f)))
               (and (substitutable-derivation? drv)
                    (package-job store (job-name package)
                                 package system))))
            (else
             #f)))))

(define (all-packages)
  "Return the list of packages to build."
  (define (adjust package result)
    (cond ((package-replacement package)
           ;; XXX: If PACKAGE and its replacement have the same name/version,
           ;; then both Cuirass jobs will have the same name, which
           ;; effectively means that the second one will be ignored.  Thus,
           ;; return the replacement first.
           (cons* (package-replacement package)   ;build both
                  package
                  result))
          ((package-superseded package)
           result)                                ;don't build it
          (else
           (cons package result))))

  (fold-packages adjust
                 (fold adjust '()                 ;include base packages
                       (match (%final-inputs)
                         (((labels packages _ ...) ...)
                          packages)))
                 #:select? (const #t)))           ;include hidden packages

(define (arguments->manifests arguments)
  "Return the list of manifests extracted from ARGUMENTS."
  (map (match-lambda
         ((input-name . relative-path)
          (let* ((checkout (assq-ref arguments (string->symbol input-name)))
                 (base (assq-ref checkout 'file-name)))
            (in-vicinity base relative-path))))
       (assq-ref arguments 'manifests)))

(define (manifests->packages store manifests)
  "Return the list of packages found in MANIFESTS."
  (define (load-manifest manifest)
    (save-module-excursion
     (lambda ()
       (set-current-module (make-user-module '((guix profiles) (gnu))))
       (primitive-load manifest))))

  (delete-duplicates!
   (map manifest-entry-item
        (append-map (compose manifest-entries
                             load-manifest)
                    manifests))))

(define (find-current-checkout arguments)
  "Find the first checkout of ARGUMENTS that provided the current file.
Return #f if no such checkout is found."
  (let ((current-root
         (canonicalize-path
          (string-append (dirname (current-filename)) "/.."))))
    (find (lambda (argument)
            (and=> (assq-ref argument 'file-name)
                   (lambda (name)
                     (string=? name current-root)))) arguments)))


;;;
;;; Hydra entry point.
;;;

(define (hydra-jobs store arguments)
  "Return Hydra jobs."
  (define subset
    (match (assoc-ref arguments 'subset)
      ("core" 'core)                              ; only build core packages
      ("hello" 'hello)                            ; only build hello
      (((? string?) (? string?) ...) 'list)       ; only build selected list of packages
      ("manifests" 'manifests)                    ; only build packages in the list of manifests
      (_ 'all)))                                  ; build everything

  (define systems
    (match (assoc-ref arguments 'systems)
      (#f              %hydra-supported-systems)
      ((lst ...)       lst)
      ((? string? str) (call-with-input-string str read))))

  (define checkout
    (or (find-current-checkout arguments)
        (assq-ref arguments 'superior-guix-checkout)))

  (define commit
    (assq-ref checkout 'revision))

  (define source
    (assq-ref checkout 'file-name))

  ;; Turn off grafts.  Grafting is meant to happen on the user's machines.
  (parameterize ((%graft? #f))
    ;; Return one job for each package, except bootstrap packages.
    (append-map (lambda (system)
                  (format (current-error-port)
                          "evaluating for '~a' (heap size: ~a MiB)...~%"
                          system
                          (round
                           (/ (assoc-ref (gc-stats) 'heap-size)
                              (expt 2. 20))))
                  (invalidate-derivation-caches!)
                  (case subset
                    ((all)
                     ;; Build everything, including replacements.
                     (let ((all (all-packages))
                           (job (lambda (package)
                                  (package->job store package
                                                system))))
                       (append (filter-map job all)
                               (image-jobs store system)
                               (system-test-jobs store system
                                                 #:source source
                                                 #:commit commit)
                               (tarball-jobs store system)
                               (cross-jobs store system))))
                    ((core)
                     ;; Build core packages only.
                     (append (map (lambda (package)
                                    (package-job store (job-name package)
                                                 package system))
                                  %core-packages)
                             (cross-jobs store system)))
                    ((hello)
                     ;; Build hello package only.
                     (let ((hello (specification->package "hello")))
                       (list (package-job store (job-name hello) hello system))))
                    ((list)
                     ;; Build selected list of packages only.
                     (let* ((names (assoc-ref arguments 'subset))
                            (packages (map specification->package names)))
                       (map (lambda (package)
                              (package-job store (job-name package)
                                           package system))
                            packages)))
                    ((manifests)
                     ;; Build packages in the list of manifests.
                     (let* ((manifests (arguments->manifests arguments))
                            (packages (manifests->packages store manifests)))
                       (map (lambda (package)
                              (package-job store (job-name package)
                                           package system))
                            packages)))
                    (else
                     (error "unknown subset" subset))))
                systems)))