aboutsummaryrefslogtreecommitdiff
path: root/guix/snix.scm
diff options
context:
space:
mode:
Diffstat (limited to 'guix/snix.scm')
-rw-r--r--guix/snix.scm439
1 files changed, 439 insertions, 0 deletions
diff --git a/guix/snix.scm b/guix/snix.scm
new file mode 100644
index 0000000000..ef98eb42a0
--- /dev/null
+++ b/guix/snix.scm
@@ -0,0 +1,439 @@
+;;; Guix --- Nix package management from Guile. -*- coding: utf-8 -*-
+;;; Copyright (C) 2010, 2011, 2012 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;; This file is part of Guix.
+;;;
+;;; 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.
+;;;
+;;; 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 Guix. If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix snix)
+ #:use-module (sxml ssax)
+ #:use-module (ice-9 popen)
+ #:use-module (ice-9 match)
+ #:use-module (ice-9 rdelim)
+ #:use-module (ice-9 format)
+ #:use-module (ice-9 regex)
+ #:use-module (ice-9 vlist)
+ #:use-module (srfi srfi-1)
+ #:use-module (srfi srfi-9)
+ #:use-module (srfi srfi-11)
+ #:use-module (srfi srfi-26)
+ #:use-module (srfi srfi-37)
+ #:use-module (system foreign)
+ #:use-module (rnrs bytevectors)
+ #:use-module (guix utils)
+ #:use-module (guix config)
+ #:export (open-nixpkgs
+ xml->snix
+ nixpkgs->guix-package))
+
+;;; Commentary:
+;;;
+;;; Converting Nix code to s-expressions, and then to Guix `package'
+;;; declarations, using the XML output of `nix-instantiate'.
+;;;
+;;; Code:
+
+
+;;;
+;;; SNix.
+;;;
+
+;; Nix object types visible in the XML output of `nix-instantiate' and
+;; mapping to S-expressions (we map to sexps, not records, so that we
+;; can do pattern matching):
+;;
+;; at (at varpat attrspat)
+;; attr (attribute loc name value)
+;; attrs (attribute-set attributes)
+;; attrspat (attribute-set-pattern patterns)
+;; bool #f|#t
+;; derivation (derivation drv-path out-path attributes)
+;; ellipsis '...
+;; expr (snix loc body ...)
+;; function (function loc at|attrspat|varpat)
+;; int int
+;; list list
+;; null 'null
+;; path string
+;; string string
+;; unevaluated 'unevaluated
+;; varpat (varpat name)
+;;
+;; Initially ATTRIBUTES in `derivation' and `attribute-set' was a promise;
+;; however, handling `repeated' nodes makes it impossible to do anything
+;; lazily because the whole SXML tree has to be traversed to maintain the
+;; list of known derivations.
+
+(define (xml-element->snix elem attributes body derivations)
+ "Return an SNix element corresponding to XML element ELEM."
+
+ (define (loc)
+ (location (assq-ref attributes 'path)
+ (assq-ref attributes 'line)
+ (assq-ref attributes 'column)))
+
+ (case elem
+ ((at)
+ (values `(at ,(car body) ,(cadr body)) derivations))
+ ((attr)
+ (let ((name (assq-ref attributes 'name)))
+ (cond ((null? body)
+ (values `(attribute-pattern ,name) derivations))
+ ((and (pair? body) (null? (cdr body)))
+ (values `(attribute ,(loc) ,name ,(car body))
+ derivations))
+ (else
+ (error "invalid attribute body" name (loc) body)))))
+ ((attrs)
+ (values `(attribute-set ,(reverse body)) derivations))
+ ((attrspat)
+ (values `(attribute-set-pattern ,body) derivations))
+ ((bool)
+ (values (string-ci=? "true" (assq-ref attributes 'value))
+ derivations))
+ ((derivation)
+ (let ((drv-path (assq-ref attributes 'drvPath))
+ (out-path (assq-ref attributes 'outPath)))
+ (if (equal? body '(repeated))
+ (let ((body (vhash-assoc drv-path derivations)))
+ (if (pair? body)
+ (values `(derivation ,drv-path ,out-path ,(cdr body))
+ derivations)
+
+ ;; DRV-PATH hasn't been encountered yet but may be later
+ ;; (see <http://article.gmane.org/gmane.linux.distributions.nixos/5946>.)
+ ;; Return an `unresolved' node.
+ (values `(unresolved
+ ,(lambda (derivations)
+ (let ((body (vhash-assoc drv-path derivations)))
+ (if (pair? body)
+ `(derivation ,drv-path ,out-path
+ ,(cdr body))
+ (error "no previous occurrence of derivation"
+ drv-path)))))
+ derivations)))
+ (values `(derivation ,drv-path ,out-path ,body)
+ (vhash-cons drv-path body derivations)))))
+ ((ellipsis)
+ (values '... derivations))
+ ((expr)
+ (values `(snix ,(loc) ,@body) derivations))
+ ((function)
+ (values `(function ,(loc) ,body) derivations))
+ ((int)
+ (values (string->number (assq-ref attributes 'value))
+ derivations))
+ ((list)
+ (values body derivations))
+ ((null)
+ (values 'null derivations))
+ ((path)
+ (values (assq-ref attributes 'value) derivations))
+ ((repeated)
+ (values 'repeated derivations))
+ ((string)
+ (values (assq-ref attributes 'value) derivations))
+ ((unevaluated)
+ (values 'unevaluated derivations))
+ ((varpat)
+ (values `(varpat ,(assq-ref attributes 'name)) derivations))
+ (else (error "unhandled Nix XML element" elem))))
+
+(define (resolve snix derivations)
+ "Return a new SNix tree where `unresolved' nodes from SNIX have been
+replaced by the result of their application to DERIVATIONS, a vhash."
+ (let loop ((node snix)
+ (seen vlist-null))
+ (if (vhash-assq node seen)
+ (values node seen)
+ (match node
+ (('unresolved proc)
+ (let ((n (proc derivations)))
+ (values n seen)))
+ ((tag body ...)
+ (let ((body+seen (fold (lambda (n body+seen)
+ (call-with-values
+ (lambda ()
+ (loop n (cdr body+seen)))
+ (lambda (n* seen)
+ (cons (cons n* (car body+seen))
+ (vhash-consq n #t seen)))))
+ (cons '() (vhash-consq node #t seen))
+ body)))
+ (values (cons tag (reverse (car body+seen)))
+ (vhash-consq node #t (cdr body+seen)))))
+ (anything
+ (values anything seen))))))
+
+(define xml->snix
+ (let ((parse
+ (ssax:make-parser NEW-LEVEL-SEED
+ (lambda (elem-gi attributes namespaces expected-content
+ seed)
+ (cons '() (cdr seed)))
+
+ FINISH-ELEMENT
+ (lambda (elem-gi attributes namespaces parent-seed
+ seed)
+ (let ((snix (car seed))
+ (derivations (cdr seed)))
+ (let-values (((snix derivations)
+ (xml-element->snix elem-gi
+ attributes
+ snix
+ derivations)))
+ (cons (cons snix (car parent-seed))
+ derivations))))
+
+ CHAR-DATA-HANDLER
+ (lambda (string1 string2 seed)
+ ;; Discard inter-node strings, which are blanks.
+ seed))))
+ (lambda (port)
+ "Return the SNix represention of TREE, an SXML tree as returned by
+parsing the XML output of `nix-instantiate' on Nixpkgs."
+ (match (parse port (cons '() vlist-null))
+ (((snix) . derivations)
+ (resolve snix derivations))))))
+
+(define (attribute-value attribute)
+ "Return the value of ATTRIBUTE."
+ (match attribute
+ (('attribute _ _ value) value)))
+
+(define (derivation-source derivation)
+ "Return the \"src\" attribute of DERIVATION or #f if not found."
+ (match derivation
+ (('derivation _ _ (attributes ...))
+ (find-attribute-by-name "src" attributes))))
+
+(define (derivation-output-path derivation)
+ "Return the output path of DERIVATION."
+ (match derivation
+ (('derivation _ out-path _)
+ out-path)
+ (_ #f)))
+
+(define (source-output-path src)
+ "Return the output path of SRC, the \"src\" attribute of a derivation."
+ (derivation-output-path (attribute-value src)))
+
+(define (source-urls src)
+ "Return the URLs of SRC, the \"src\" attribute of a derivation."
+ (match src
+ (('attribute _ _ ('derivation _ _ (attributes ...)))
+ (match (find-attribute-by-name "urls" attributes)
+ (('attribute _ _ value)
+ value)))
+ (_ #f)))
+
+(define (source-sha256 src)
+ "Return the sha256 of SRC, the \"src\" attribute of a derivation, as a
+bytevector."
+ (match src
+ (('attribute _ _ ('derivation _ _ (attributes ...)))
+ (match (find-attribute-by-name "outputHash" attributes)
+ (('attribute _ _ value)
+ (match value
+ ((= string-length 52)
+ (nix-base32-string->bytevector value))
+ ((= string-length 64)
+ (base16-string->bytevector value))
+ (_
+ (error "unsupported hash format" value))))))
+ (_ #f)))
+
+(define (derivation-source-output-path derivation)
+ "Return the output path of the \"src\" attribute of DERIVATION or #f
+if DERIVATION lacks an \"src\" attribute."
+ (and=> (derivation-source derivation) source-output-path))
+
+(define* (open-nixpkgs nixpkgs #:optional attribute)
+ "Return an input pipe to the XML representation of Nixpkgs. When
+ATTRIBUTE is true, only that attribute is considered."
+ (with-fluids ((%default-port-encoding "UTF-8"))
+ (let ((cross-system (format #f "{
+ config = \"i686-guix-linux-gnu\";
+ libc = \"glibc\";
+ arch = \"guix\";
+ withTLS = true;
+ float = \"hard\";
+ openssl.system = \"linux-generic32\";
+ platform = (import ~a/pkgs/top-level/platforms.nix).sheevaplug;
+}" nixpkgs)))
+ (apply open-pipe* OPEN_READ
+ %nix-instantiate "--strict" "--eval-only" "--xml"
+
+ ;; Pass a dummy `crossSystem' argument so that `buildInputs' and
+ ;; `buildNativeInputs' are not coalesced.
+ ;; XXX: This is hacky and has other problems.
+ ;"--arg" "crossSystem" cross-system
+
+ `(,@(if attribute
+ `("-A" ,attribute)
+ '())
+ ,nixpkgs)))))
+
+(define (pipe-failed? pipe)
+ "Close pipe and return its status if it failed."
+ (let ((status (close-pipe pipe)))
+ (if (or (status:term-sig status)
+ (not (= (status:exit-val status) 0)))
+ status
+ #f)))
+
+(define (find-attribute-by-name name attributes)
+ "Return attribute NAME in ATTRIBUTES, an attribute set or list of SNix
+attributes, or #f if NAME cannot be found."
+ (find (lambda (a)
+ (match a
+ (('attribute _ (? (cut string=? <> name)) _)
+ a)
+ (_ #f)))
+ (match attributes
+ (('attribute-set (attributes ...))
+ attributes)
+ (_
+ attributes))))
+
+(define (package-source-output-path package)
+ "Return the output path of the \"src\" derivation of PACKAGE."
+ (derivation-source-output-path (attribute-value package)))
+
+
+;;;
+;;; Conversion of "Nix expressions" to "Guix expressions".
+;;;
+
+(define (factorize-uri uri version)
+ "Factorize URI, a package tarball URI as a string, such that any occurrences
+of the string VERSION is replaced by the symbol 'version."
+ (let ((version-rx (make-regexp (regexp-quote version))))
+ (match (regexp-exec version-rx uri)
+ (#f
+ uri)
+ (_
+ (let ((indices (fold-matches version-rx uri
+ '((0))
+ (lambda (m result)
+ (match result
+ (((start) rest ...)
+ `((,(match:end m))
+ (,start . ,(match:start m))
+ ,@rest)))))))
+ (fold (lambda (index result)
+ (match index
+ ((start)
+ (cons (substring uri start)
+ result))
+ ((start . end)
+ (cons* (substring uri start end)
+ 'version
+ result))))
+ '()
+ indices))))))
+
+(define (snix-derivation->guix-package derivation)
+ "Return the `package' s-expression corresponding to SNix DERIVATION, a
+Nixpkgs `stdenv.mkDerivation'-style derivation, and the original source
+location of DERIVATION."
+ (match derivation
+ (('derivation _ _ (attributes ...))
+ (let*-values (((full-name loc)
+ (match (find-attribute-by-name "name" attributes)
+ (('attribute loc _ value)
+ (values value loc))
+ (_
+ (values #f #f))))
+ ((name version)
+ (package-name->name+version full-name)))
+ (define (convert-inputs type)
+ ;; Convert the derivation's input from a list of SNix derivations to
+ ;; a list of name/variable pairs.
+ (match (and=> (find-attribute-by-name type attributes)
+ attribute-value)
+ (#f
+ '())
+ ((('derivation _ _ (attributes ...)) ...)
+ (map (lambda (attrs)
+ (let* ((full-name (attribute-value
+ (find-attribute-by-name "name" attrs)))
+ (name (package-name->name+version full-name)))
+ (list name
+ (list 'unquote
+ (string->symbol name)))))
+ attributes))))
+
+ (define (maybe-inputs guix-name inputs)
+ (match inputs
+ (()
+ '())
+ ((inputs ...)
+ (list (list guix-name
+ (list 'quasiquote inputs))))))
+
+ (define (pretty-uri uri version)
+ (match (factorize-uri uri version)
+ ((items ...)
+ `(string-append ,@items))
+ (x x)))
+
+ (let* ((source (find-attribute-by-name "src" attributes))
+ (urls (source-urls source))
+ (sha256 (source-sha256 source))
+ (meta (and=> (find-attribute-by-name "meta" attributes)
+ attribute-value)))
+ (values
+ `(package
+ (name ,name)
+ (version ,version)
+ (source (origin
+ (method http-fetch)
+ (uri ,(pretty-uri (car urls) version))
+ (sha256
+ (base32
+ ,(bytevector->nix-base32-string sha256)))))
+ (build-system gnu-build-system)
+
+ ;; When doing a native Nixpkgs build, `buildInputs' is empty and
+ ;; everything is in `buildNativeInputs'. So we can't distinguish
+ ;; between both, here.
+ ,@(maybe-inputs 'inputs
+ (convert-inputs "buildNativeInputs"))
+ ,@(maybe-inputs 'propagated-inputs
+ (convert-inputs "propagatedBuildNativeInputs"))
+
+ (home-page ,(and=> (find-attribute-by-name "homepage" meta)
+ attribute-value))
+ (synopsis ,(and=> (find-attribute-by-name "description" meta)
+ attribute-value))
+ (description
+ ,(and=> (find-attribute-by-name "longDescription" meta)
+ attribute-value))
+ (license ,(and=> (find-attribute-by-name "license" meta)
+ attribute-value)))
+ loc))))))
+
+(define (nixpkgs->guix-package nixpkgs attribute)
+ "Evaluate ATTRIBUTE in NIXPKGS, the file name of a Nixpkgs checkout,
+and return the `package' s-expression corresponding to that package."
+ (let ((port (open-nixpkgs nixpkgs attribute)))
+ (match (xml->snix port)
+ (('snix loc (and drv ('derivation _ ...)))
+ (and (not (pipe-failed? port))
+ (snix-derivation->guix-package drv)))
+ (_
+ (not (pipe-failed? port))))))
+
+;;; snix.scm ends here
generated by cgit v1.2.3 (git 2.45.0) at 2024-12-22 02:45:48 +0000