guix-devel/guix/ui.scm

422 lines
16 KiB
Scheme
Raw Normal View History

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012, 2013 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2013 Mark H Weaver <mhw@netris.org>
;;; Copyright © 2013 Nikita Karetnikov <nikita@karetnikov.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 ui)
#:use-module (guix utils)
#:use-module (guix store)
#:use-module (guix config)
#:use-module (guix packages)
#:use-module (guix derivations)
#:use-module ((guix licenses) #:select (license? license-name))
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-11)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-34)
#:use-module (srfi srfi-37)
#:use-module (ice-9 match)
#:use-module (ice-9 format)
#:export (_
N_
leave
show-version-and-exit
show-bug-report-information
show-what-to-build
call-with-error-handling
with-error-handling
read/eval-package-expression
location->string
switch-symlinks
config-directory
fill-paragraph
string->recutils
package->recutils
args-fold*
run-guix-command
program-name
guix-warning-port
warning
guix-main))
;;; Commentary:
;;;
;;; User interface facilities for command-line tools.
;;;
;;; Code:
(define %gettext-domain
"guix")
(define _ (cut gettext <> %gettext-domain))
(define N_ (cut ngettext <> <> <> %gettext-domain))
(define-syntax-rule (define-diagnostic name prefix)
"Create a diagnostic macro (i.e., NAME), which will prepend PREFIX to all
messages."
(define-syntax name
(lambda (x)
(define (augmented-format-string fmt)
(string-append "~:[~*~;guix ~a: ~]~a" (syntax->datum fmt)))
(syntax-case x (N_ _) ; these are literals, yeah...
((name (_ fmt) args (... ...))
(string? (syntax->datum #'fmt))
(with-syntax ((fmt* (augmented-format-string #'fmt))
(prefix (datum->syntax x prefix)))
#'(format (guix-warning-port) (gettext fmt*)
(program-name) (program-name) prefix
args (... ...))))
((name (N_ singular plural n) args (... ...))
(and (string? (syntax->datum #'singular))
(string? (syntax->datum #'plural)))
(with-syntax ((s (augmented-format-string #'singular))
(p (augmented-format-string #'plural))
(prefix (datum->syntax x prefix)))
#'(format (guix-warning-port)
(ngettext s p n %gettext-domain)
(program-name) (program-name) prefix
args (... ...))))))))
(define-diagnostic warning "warning: ") ; emit a warning
(define-diagnostic report-error "error: ")
(define-syntax-rule (leave args ...)
"Emit an error message and exit."
(begin
(report-error args ...)
(exit 1)))
(define (install-locale)
"Install the current locale settings."
(catch 'system-error
(lambda _
(setlocale LC_ALL ""))
(lambda args
(warning (_ "failed to install locale: ~a~%")
(strerror (system-error-errno args))))))
(define (initialize-guix)
"Perform the usual initialization for stand-alone Guix commands."
(install-locale)
(textdomain "guix")
(setvbuf (current-output-port) _IOLBF)
(setvbuf (current-error-port) _IOLBF))
(define* (show-version-and-exit #:optional (command (car (command-line))))
"Display version information for COMMAND and `(exit 0)'."
(simple-format #t "~a (~a) ~a~%"
command %guix-package-name %guix-version)
(exit 0))
(define (show-bug-report-information)
(format #t (_ "
Report bugs to: ~a.") %guix-bug-report-address)
(format #t (_ "
~a home page: <~a>") %guix-package-name %guix-home-page-url)
(display (_ "
General help using GNU software: <http://www.gnu.org/gethelp/>"))
(newline))
(define (call-with-error-handling thunk)
"Call THUNK within a user-friendly error handler."
(guard (c ((package-input-error? c)
(let* ((package (package-error-package c))
(input (package-error-invalid-input c))
(location (package-location package))
(file (location-file location))
(line (location-line location))
(column (location-column location)))
(leave (_ "~a:~a:~a: package `~a' has an invalid input: ~s~%")
file line column
(package-full-name package) input)))
((nix-connection-error? c)
(leave (_ "failed to connect to `~a': ~a~%")
(nix-connection-error-file c)
(strerror (nix-connection-error-code c))))
((nix-protocol-error? c)
;; FIXME: Server-provided error messages aren't i18n'd.
(leave (_ "build failed: ~a~%")
(nix-protocol-error-message c))))
(thunk)))
(define (read/eval-package-expression str)
"Read and evaluate STR and return the package it refers to, or exit an
error."
(let ((exp (catch #t
(lambda ()
(call-with-input-string str read))
(lambda args
(leave (_ "failed to read expression ~s: ~s~%")
str args)))))
(let ((p (catch #t
(lambda ()
(eval exp the-scm-module))
(lambda args
(leave (_ "failed to evaluate expression `~a': ~s~%")
exp args)))))
(if (package? p)
p
(leave (_ "expression `~s' does not evaluate to a package~%")
exp)))))
(define* (show-what-to-build store drv
#:key dry-run? (use-substitutes? #t))
"Show what will or would (depending on DRY-RUN?) be built in realizing the
derivations listed in DRV. Return #t if there's something to build, #f
otherwise. When USE-SUBSTITUTES?, check and report what is prerequisites are
available for download."
(let*-values (((build download)
(fold2 (lambda (drv-path build download)
(let ((drv (call-with-input-file drv-path
read-derivation)))
(let-values (((b d)
(derivation-prerequisites-to-build
store drv
#:use-substitutes?
use-substitutes?)))
(values (append b build)
(append d download)))))
'() '()
drv))
((build) ; add the DRV themselves
(delete-duplicates
(append (remove (compose (lambda (out)
(or (valid-path? store out)
(and use-substitutes?
(has-substitutes? store
out))))
derivation-path->output-path)
drv)
(map derivation-input-path build))))
((download) ; add the references of DOWNLOAD
(delete-duplicates
(append download
(remove (cut valid-path? store <>)
(append-map
substitutable-references
(substitutable-path-info store download)))))))
(if dry-run?
(begin
(format (current-error-port)
(N_ "~:[The following derivation would be built:~%~{ ~a~%~}~;~]"
"~:[The following derivations would be built:~%~{ ~a~%~}~;~]"
(length build))
(null? build) build)
(format (current-error-port)
(N_ "~:[The following file would be downloaded:~%~{ ~a~%~}~;~]"
"~:[The following files would be downloaded:~%~{ ~a~%~}~;~]"
(length download))
(null? download) download))
(begin
(format (current-error-port)
(N_ "~:[The following derivation will be built:~%~{ ~a~%~}~;~]"
"~:[The following derivations will be built:~%~{ ~a~%~}~;~]"
(length build))
(null? build) build)
(format (current-error-port)
(N_ "~:[The following file will be downloaded:~%~{ ~a~%~}~;~]"
"~:[The following files will be downloaded:~%~{ ~a~%~}~;~]"
(length download))
(null? download) download)))
(pair? build)))
(define-syntax with-error-handling
(syntax-rules ()
"Run BODY within a user-friendly error condition handler."
((_ body ...)
(call-with-error-handling
(lambda ()
body ...)))))
(define (location->string loc)
"Return a human-friendly, GNU-standard representation of LOC."
(match loc
(#f (_ "<unknown location>"))
(($ <location> file line column)
(format #f "~a:~a:~a" file line column))))
(define (switch-symlinks link target)
"Atomically switch LINK, a symbolic link, to point to TARGET. Works
both when LINK already exists and when it does not."
(let ((pivot (string-append link ".new")))
(symlink target pivot)
(rename-file pivot link)))
(define (config-directory)
"Return the name of the configuration directory, after making sure that it
exists. Honor the XDG specs,
<http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html>."
(let ((dir (and=> (or (getenv "XDG_CONFIG_HOME")
(and=> (getenv "HOME")
(cut string-append <> "/.config")))
(cut string-append <> "/guix"))))
(catch 'system-error
(lambda ()
(mkdir dir)
dir)
(lambda args
(match (system-error-errno args)
((or EEXIST 0)
dir)
(err
(leave (_ "failed to create configuration directory `~a': ~a~%")
dir (strerror err))))))))
(define* (fill-paragraph str width #:optional (column 0))
"Fill STR such that each line contains at most WIDTH characters, assuming
that the first character is at COLUMN.
When STR contains a single line break surrounded by other characters, it is
converted to a space; sequences of more than one line break are preserved."
(define (maybe-break chr result)
(match result
((column newlines chars)
(case chr
((#\newline)
`(,column ,(+ 1 newlines) ,chars))
(else
(let ((chars (case newlines
((0) chars)
((1) (cons #\space chars))
(else
(append (make-list newlines #\newline) chars))))
(column (case newlines
((0) column)
((1) (+ 1 column))
(else 0))))
(let ((chars (cons chr chars))
(column (+ 1 column)))
(if (> column width)
(let*-values (((before after)
(break (cut eqv? #\space <>) chars))
((len)
(length before)))
(if (<= len width)
`(,len
0
,(if (null? after)
before
(append before (cons #\newline (cdr after)))))
`(,column 0 ,chars))) ; unbreakable
`(,column 0 ,chars)))))))))
(match (string-fold maybe-break
`(,column 0 ())
str)
((_ _ chars)
(list->string (reverse chars)))))
(define (string->recutils str)
"Return a version of STR where newlines have been replaced by newlines
followed by \"+ \", which makes for a valid multi-line field value in the
`recutils' syntax."
(list->string
(string-fold-right (lambda (chr result)
(if (eqv? chr #\newline)
(cons* chr #\+ #\space result)
(cons chr result)))
'()
str)))
(define* (package->recutils p port
#:optional (width (or (and=> (getenv "WIDTH")
string->number)
80)))
"Write to PORT a `recutils' record of package P, arranging to fit within
WIDTH columns."
(define (description->recutils str)
(let ((str (_ str)))
(string->recutils
(fill-paragraph str width
(string-length "description: ")))))
;; Note: Don't i18n field names so that people can post-process it.
(format port "name: ~a~%" (package-name p))
(format port "version: ~a~%" (package-version p))
(format port "location: ~a~%"
(or (and=> (package-location p) location->string)
(_ "unknown")))
(format port "home-page: ~a~%" (package-home-page p))
(format port "license: ~a~%"
(match (package-license p)
(((? license? licenses) ...)
(string-join (map license-name licenses)
", "))
((? license? license)
(license-name license))
(x
(_ "unknown"))))
(format port "synopsis: ~a~%"
(string-map (match-lambda
(#\newline #\space)
(chr chr))
(or (and=> (package-synopsis p) _)
"")))
(format port "description: ~a~%"
(and=> (package-description p) description->recutils))
(newline port))
(define (args-fold* options unrecognized-option-proc operand-proc . seeds)
"A wrapper on top of `args-fold' that does proper user-facing error
reporting."
(catch 'misc-error
(lambda ()
(apply args-fold options unrecognized-option-proc
operand-proc seeds))
(lambda (key proc msg args . rest)
;; XXX: MSG is not i18n'd.
(leave (_ "invalid argument: ~a~%")
(apply format #f msg args)))))
(define (show-guix-usage)
;; TODO: Dynamically generate a summary of available commands.
(format (current-error-port)
(_ "Usage: guix COMMAND ARGS...~%")))
(define (run-guix-command command . args)
;; TODO: Gracefully report errors
(let* ((module (resolve-interface `(guix scripts ,command)))
(command-main (module-ref module
(symbol-append 'guix- command))))
(apply command-main args)))
(define program-name
;; Name of the command-line program currently executing, or #f.
(make-parameter #f))
(define guix-warning-port
(make-parameter (current-warning-port)))
(define (guix-main arg0 . args)
(initialize-guix)
(let ()
(define (option? str) (string-prefix? "-" str))
(match args
(() (show-guix-usage) (exit 1))
(("--help") (show-guix-usage))
(("--version") (show-version-and-exit "guix"))
(((? option?) args ...) (show-guix-usage) (exit 1))
((command args ...)
(parameterize ((program-name command))
(apply run-guix-command
(string->symbol command)
args))))))
;;; ui.scm ends here