mirror of
https://git.in.rschanz.org/ryan77627/guix.git
synced 2024-11-14 10:55:23 -05:00
210 lines
8.5 KiB
Scheme
210 lines
8.5 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
|
|
;;; Copyright © 2013, 2014, 2015, 2017, 2018 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 search-paths)
|
|
#:use-module (guix records)
|
|
#:use-module (guix build utils)
|
|
#:use-module (srfi srfi-1)
|
|
#:use-module (srfi srfi-26)
|
|
#:use-module (ice-9 match)
|
|
#:export (<search-path-specification>
|
|
search-path-specification
|
|
search-path-specification?
|
|
search-path-specification-variable
|
|
search-path-specification-files
|
|
search-path-specification-separator
|
|
search-path-specification-file-type
|
|
search-path-specification-file-pattern
|
|
|
|
$PATH
|
|
|
|
search-path-specification->sexp
|
|
sexp->search-path-specification
|
|
string-tokenize*
|
|
evaluate-search-paths
|
|
environment-variable-definition
|
|
search-path-definition
|
|
set-search-paths))
|
|
|
|
;;; Commentary:
|
|
;;;
|
|
;;; This module defines "search path specifications", which allow packages to
|
|
;;; declare environment variables that they use to define search paths. For
|
|
;;; instance, GCC has the 'CPATH' variable, Guile has the 'GUILE_LOAD_PATH'
|
|
;;; variable, etc.
|
|
;;;
|
|
;;; Code:
|
|
|
|
;; The specification of a search path.
|
|
(define-record-type* <search-path-specification>
|
|
search-path-specification make-search-path-specification
|
|
search-path-specification?
|
|
(variable search-path-specification-variable) ;string
|
|
(files search-path-specification-files) ;list of strings
|
|
(separator search-path-specification-separator ;string | #f
|
|
(default ":"))
|
|
(file-type search-path-specification-file-type ;symbol
|
|
(default 'directory))
|
|
(file-pattern search-path-specification-file-pattern ;#f | string
|
|
(default #f)))
|
|
|
|
(define $PATH
|
|
;; The 'PATH' variable. This variable is a bit special: it is not attached
|
|
;; to any package in particular.
|
|
(search-path-specification
|
|
(variable "PATH")
|
|
(files '("bin" "sbin"))))
|
|
|
|
(define (search-path-specification->sexp spec)
|
|
"Return an sexp representing SPEC, a <search-path-specification>. The sexp
|
|
corresponds to the arguments expected by `set-path-environment-variable'."
|
|
;; Note that this sexp format is used both by build systems and in
|
|
;; (guix profiles), so think twice before you change it.
|
|
(match spec
|
|
(($ <search-path-specification> variable files separator type pattern)
|
|
`(,variable ,files ,separator ,type ,pattern))))
|
|
|
|
(define (sexp->search-path-specification sexp)
|
|
"Convert SEXP, which is as returned by 'search-path-specification->sexp', to
|
|
a <search-path-specification> object."
|
|
(match sexp
|
|
((variable files separator type pattern)
|
|
(search-path-specification
|
|
(variable variable)
|
|
(files files)
|
|
(separator separator)
|
|
(file-type type)
|
|
(file-pattern pattern)))))
|
|
|
|
(define-syntax-rule (with-null-error-port exp)
|
|
"Evaluate EXP with the error port pointing to the bit bucket."
|
|
(with-error-to-port (%make-void-port "w")
|
|
(lambda () exp)))
|
|
|
|
;; XXX: This procedure used to be in (guix utils) but since we want to be able
|
|
;; to use (guix search-paths) on the build side, we want to avoid the
|
|
;; dependency on (guix utils), and so this procedure is back here for now.
|
|
(define (string-tokenize* string separator)
|
|
"Return the list of substrings of STRING separated by SEPARATOR. This is
|
|
like `string-tokenize', but SEPARATOR is a string."
|
|
(define (index string what)
|
|
(let loop ((string string)
|
|
(offset 0))
|
|
(cond ((string-null? string)
|
|
#f)
|
|
((string-prefix? what string)
|
|
offset)
|
|
(else
|
|
(loop (string-drop string 1) (+ 1 offset))))))
|
|
|
|
(define len
|
|
(string-length separator))
|
|
|
|
(let loop ((string string)
|
|
(result '()))
|
|
(cond ((index string separator)
|
|
=>
|
|
(lambda (offset)
|
|
(loop (string-drop string (+ offset len))
|
|
(cons (substring string 0 offset)
|
|
result))))
|
|
(else
|
|
(reverse (cons string result))))))
|
|
|
|
(define* (evaluate-search-paths search-paths directories
|
|
#:optional (getenv (const #f)))
|
|
"Evaluate SEARCH-PATHS, a list of search-path specifications, for
|
|
DIRECTORIES, a list of directory names, and return a list of
|
|
specification/value pairs. Use GETENV to determine the current settings and
|
|
report only settings not already effective."
|
|
(define (search-path-definition spec)
|
|
(match spec
|
|
(($ <search-path-specification> variable files #f type pattern)
|
|
;; Separator is #f so return the first match.
|
|
(match (with-null-error-port
|
|
(search-path-as-list files directories
|
|
#:type type
|
|
#:pattern pattern))
|
|
(()
|
|
#f)
|
|
((head . _)
|
|
(let ((value (getenv variable)))
|
|
(if (and value (string=? value head))
|
|
#f ;VARIABLE already set appropriately
|
|
(cons spec head))))))
|
|
(($ <search-path-specification> variable files separator
|
|
type pattern)
|
|
(let* ((values (or (and=> (getenv variable)
|
|
(cut string-tokenize* <> separator))
|
|
'()))
|
|
;; XXX: Silence 'find-files' when it stumbles upon non-existent
|
|
;; directories (see
|
|
;; <http://lists.gnu.org/archive/html/guix-devel/2015-01/msg00269.html>.)
|
|
(path (with-null-error-port
|
|
(search-path-as-list files directories
|
|
#:type type
|
|
#:pattern pattern))))
|
|
(if (every (cut member <> values) path)
|
|
#f ;VARIABLE is already set appropriately
|
|
(cons spec (string-join path separator)))))))
|
|
|
|
(filter-map search-path-definition search-paths))
|
|
|
|
(define* (environment-variable-definition variable value
|
|
#:key
|
|
(kind 'exact)
|
|
(separator ":"))
|
|
"Return a the definition of VARIABLE to VALUE in Bash syntax.
|
|
|
|
KIND can be either 'exact (return the definition of VARIABLE=VALUE),
|
|
'prefix (return the definition where VALUE is added as a prefix to VARIABLE's
|
|
current value), or 'suffix (return the definition where VALUE is added as a
|
|
suffix to VARIABLE's current value.) In the case of 'prefix and 'suffix,
|
|
SEPARATOR is used as the separator between VARIABLE's current value and its
|
|
prefix/suffix."
|
|
(match (if (not separator) 'exact kind)
|
|
('exact
|
|
(format #f "export ~a=\"~a\"" variable value))
|
|
('prefix
|
|
(format #f "export ~a=\"~a${~a:+~a}$~a\""
|
|
variable value variable separator variable))
|
|
('suffix
|
|
(format #f "export ~a=\"$~a${~a:+~a}~a\""
|
|
variable variable variable separator value))))
|
|
|
|
(define* (search-path-definition search-path value
|
|
#:key (kind 'exact))
|
|
"Similar to 'environment-variable-definition', but applied to a
|
|
<search-path-specification>."
|
|
(match search-path
|
|
(($ <search-path-specification> variable _ separator)
|
|
(environment-variable-definition variable value
|
|
#:kind kind
|
|
#:separator separator))))
|
|
|
|
(define* (set-search-paths search-paths directories
|
|
#:key (setenv setenv))
|
|
"Set the search path environment variables specified by SEARCH-PATHS for the
|
|
given directories."
|
|
(for-each (match-lambda
|
|
((spec . value)
|
|
(setenv (search-path-specification-variable spec)
|
|
value)))
|
|
(evaluate-search-paths search-paths directories)))
|
|
|
|
;;; search-paths.scm ends here
|