summaryrefslogtreecommitdiff
path: root/guix/build/profiles.scm
blob: 5c96fe9067a00780b65299bcd9b6f96356e81c95 (about) (plain)
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
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2015, 2017 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 build profiles)
  #:use-module (guix build union)
  #:use-module (guix build utils)
  #:use-module (guix search-paths)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 ftw)
  #:use-module (ice-9 match)
  #:use-module (ice-9 pretty-print)
  #:export (ensure-writable-directory
            build-profile))

;;; Commentary:
;;;
;;; Build a user profile (essentially the union of all the installed packages)
;;; with its associated meta-data.
;;;
;;; Code:

(define (abstract-profile profile)
  "Return a procedure that replaces PROFILE in VALUE with a reference to the
'GUIX_PROFILE' environment variable.  This allows users to specify what the
user-friendly name of the profile is, for instance ~/.guix-profile rather than
/gnu/store/...-profile."
  (let ((replacement (string-append "${GUIX_PROFILE:-" profile "}"))
        (crop        (cute string-drop <> (string-length profile))))
    (match-lambda
      ((search-path . value)
       (match (search-path-specification-separator search-path)
         (#f
          (cons search-path
                (string-append replacement (crop value))))
         ((? string? separator)
          (let ((items (string-tokenize* value separator)))
            (cons search-path
                  (string-join (map (lambda (str)
                                      (string-append replacement (crop str)))
                                    items)
                               separator)))))))))

(define (write-environment-variable-definition port)
  "Write the given environment variable definition to PORT."
  (match-lambda
    ((search-path . value)
     (display (search-path-definition search-path value #:kind 'prefix)
              port)
     (newline port))))

(define (build-etc/profile output search-paths)
  "Build the 'OUTPUT/etc/profile' shell file containing environment variable
definitions for all the SEARCH-PATHS."
  (mkdir-p (string-append output "/etc"))
  (call-with-output-file (string-append output "/etc/profile")
    (lambda (port)
      ;; The use of $GUIX_PROFILE described below is not great.  Another
      ;; option would have been to use "$1" and have users run:
      ;;
      ;;   source ~/.guix-profile/etc/profile ~/.guix-profile
      ;;
      ;; However, when 'source' is used with no arguments, $1 refers to the
      ;; first positional parameter of the calling script, so we cannot rely
      ;; on it.
      (display "\
# Source this file to define all the relevant environment variables in Bash
# for this profile.  You may want to define the 'GUIX_PROFILE' environment
# variable to point to the \"visible\" name of the profile, like this:
#
#  GUIX_PROFILE=/path/to/profile \\
#  source /path/to/profile/etc/profile
#
# When GUIX_PROFILE is undefined, the various environment variables refer
# to this specific profile generation.
\n" port)
      (let ((variables (evaluate-search-paths (cons $PATH search-paths)
                                              (list output))))
        (for-each (write-environment-variable-definition port)
                  (map (abstract-profile output) variables))))))

(define (ensure-writable-directory directory)
  "Ensure DIRECTORY exists and is writable.  If DIRECTORY is currently a
symlink (to a read-only directory in the store), then delete the symlink and
instead make DIRECTORY a \"real\" directory containing symlinks."
  (define (unsymlink link)
    (let* ((target (readlink link))
           ;; TARGET might itself be a symlink, so append "/" to make sure
           ;; 'scandir' enters it.
           (files  (scandir (string-append target "/")
                            (negate (cut member <> '("." ".."))))))
      (delete-file link)
      (mkdir link)
      (for-each (lambda (file)
                  (symlink (string-append target "/" file)
                           (string-append link "/" file)))
                files)))

  (catch 'system-error
    (lambda ()
      (mkdir directory))
    (lambda args
      (let ((errno (system-error-errno args)))
        (if (= errno EEXIST)
            (let ((stat (lstat directory)))
              (case (stat:type stat)
                ((symlink)
                 ;; "Unsymlink" DIRECTORY so that it is writable.
                 (unsymlink directory))
                ((directory)
                 #t)
                (else
                 (error "cannot mkdir because a same-named file exists"
                        directory))))
            (apply throw args))))))

(define* (build-profile output inputs
                        #:key manifest search-paths)
  "Build a user profile from INPUTS in directory OUTPUT.  Write MANIFEST, an
sexp, to OUTPUT/manifest.  Create OUTPUT/etc/profile with Bash definitions for
-all the variables listed in SEARCH-PATHS."
  ;; Make the symlinks.
  (union-build output inputs
               #:log-port (%make-void-port "w"))

  ;; Store meta-data.
  (call-with-output-file (string-append output "/manifest")
    (lambda (p)
      (pretty-print manifest p)))

  ;; Make sure we can write to 'OUTPUT/etc'.  'union-build' above could have
  ;; made 'etc' a symlink to a read-only sub-directory in the store so we need
  ;; to work around that.
  (ensure-writable-directory (string-append output "/etc"))

  ;; Write 'OUTPUT/etc/profile'.
  (build-etc/profile output search-paths))

;;; profile.scm ends here