03/07: build-self: Use (guix self).

[Ludovic Courtès]

civodul pushed a commit to branch wip-pull-multiple-derivations
in repository guix.

commit be323c875c1ac1f5fc15291d34b2c1b96293f711
Author: Ludovic Courtès <address@hidden>
Date:   Fri Mar 23 17:18:15 2018 +0100

    build-self: Use (guix self).
    
    This mitigates <https://bugs.gnu.org/27284>.
    
    * build-aux/build-self.scm (libgcrypt, zlib, gzip, bzip2, xz)
    (false-if-wrong-guile, package-for-current-guile, guile-json)
    (guile-ssh, guile-git, guile-bytestructures, matching-guile-2.2): Remove.
    (%dependency-variables, %persona-variables, %config-variables): New
    variables.
    (make-config.scm, load-path-expression, gexp->script)
    (build-program): New procedures.
    (build): Rewrite to simply delegate to 'guix-derivation'.
---
 build-aux/build-self.scm | 419 +++++++++++++++++++++++------------------------
 1 file changed, 201 insertions(+), 218 deletions(-)

diff --git a/build-aux/build-self.scm b/build-aux/build-self.scm
index 4c85c09..f46991e 100644
--- a/build-aux/build-self.scm
+++ b/build-aux/build-self.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2014, 2016, 2017 Ludovic Courtès <address@hidden>
+;;; Copyright © 2014, 2016, 2017, 2018 Ludovic Courtès <address@hidden>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -19,10 +19,14 @@
 (define-module (build-self)
   #:use-module (gnu)
   #:use-module (guix)
+  #:use-module (guix ui)
   #:use-module (guix config)
+  #:use-module (guix modules)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-19)
+  #:use-module (rnrs io ports)
   #:use-module (ice-9 match)
+  #:use-module (ice-9 popen)
   #:export (build))
 
 ;;; Commentary:
@@ -40,116 +44,195 @@
 ;;; Code:
 
 
-;; The dependencies.  Don't refer explicitly to the variables because they
-;; could be renamed or shuffled around in modules over time.  Conversely,
-;; 'find-best-packages-by-name' is expected to always have the same semantics.
-
-(define guix
-  (first (find-best-packages-by-name "guix" #f)))
-
-(define libgcrypt
-  (first (find-best-packages-by-name "libgcrypt" #f)))
-
-(define zlib
-  (first (find-best-packages-by-name "zlib" #f)))
-
-(define gzip
-  (first (find-best-packages-by-name "gzip" #f)))
-
-(define bzip2
-  (first (find-best-packages-by-name "bzip2" #f)))
-
-(define xz
-  (first (find-best-packages-by-name "xz" #f)))
-
-(define (false-if-wrong-guile package)
-  "Return #f if PACKAGE depends on the \"wrong\" major version of Guile (e.g.,
-2.0 instead of 2.2), otherwise return PACKAGE."
-  (let ((guile (any (match-lambda
-                      ((label (? package? dep) _ ...)
-                       (and (string=? (package-name dep) "guile")
-                            dep)))
-                    (package-direct-inputs package))))
-    (and (or (not guile)
-             (string-prefix? (effective-version)
-                             (package-version guile)))
-         package)))
-
-(define (package-for-current-guile . names)
-  "Return the package with one of the given NAMES that depends on the current
-Guile major version (2.0 or 2.2), or #f if none of the packages matches."
-  (let loop ((names names))
-    (match names
-      (()
-       #f)
-      ((name rest ...)
-       (match (find-best-packages-by-name name #f)
-         (()
-          (loop rest))
-         ((first _ ...)
-          (or (false-if-wrong-guile first)
-              (loop rest))))))))
-
-(define guile-json
-  (package-for-current-guile "guile-json"
-                             "guile2.2-json"
-                             "guile2.0-json"))
-
-(define guile-ssh
-  (package-for-current-guile "guile-ssh"
-                             "guile2.2-ssh"
-                             "guile2.0-ssh"))
+;;;
+;;; Generating (guix config).
+;;;
+;;; This is copied from (guix self) because we cannot assume (guix self) is
+;;; available at this point.
+;;;
 
-(define guile-git
-  (package-for-current-guile "guile-git"
-                             "guile2.0-git"))
+(define %dependency-variables
+  ;; (guix config) variables corresponding to dependencies.
+  '(%libgcrypt %libz %xz %gzip %bzip2 %nix-instantiate))
+
+(define %persona-variables
+  ;; (guix config) variables that define Guix's persona.
+  '(%guix-package-name
+    %guix-version
+    %guix-bug-report-address
+    %guix-home-page-url))
+
+(define %config-variables
+  ;; (guix config) variables corresponding to Guix configuration (storedir,
+  ;; localstatedir, etc.)
+  (sort (filter pair?
+                (module-map (lambda (name var)
+                              (and (not (memq name %dependency-variables))
+                                   (not (memq name %persona-variables))
+                                   (cons name (variable-ref var))))
+                            (resolve-interface '(guix config))))
+        (lambda (name+value1 name+value2)
+          (string<? (symbol->string (car name+value1))
+                    (symbol->string (car name+value2))))))
+
+(define* (make-config.scm #:key libgcrypt zlib gzip xz bzip2
+                          (package-name "GNU Guix")
+                          (package-version "0")
+                          (bug-report-address "address@hidden")
+                          (home-page-url "https://gnu.org/s/guix";))
+
+  ;; Hack so that Geiser is not confused.
+  (define defmod 'define-module)
+
+  (scheme-file "config.scm"
+               #~(begin
+                   (#$defmod (guix config)
+                     #:export (%guix-package-name
+                               %guix-version
+                               %guix-bug-report-address
+                               %guix-home-page-url
+                               %libgcrypt
+                               %libz
+                               %gzip
+                               %bzip2
+                               %xz
+                               %nix-instantiate))
+
+                   ;; XXX: Work around <http://bugs.gnu.org/15602>.
+                   (eval-when (expand load eval)
+                     #$@(map (match-lambda
+                               ((name . value)
+                                #~(define-public #$name #$value)))
+                             %config-variables)
+
+                     (define %guix-package-name #$package-name)
+                     (define %guix-version #$package-version)
+                     (define %guix-bug-report-address #$bug-report-address)
+                     (define %guix-home-page-url #$home-page-url)
+
+                     (define %gzip
+                       #+(and gzip (file-append gzip "/bin/gzip")))
+                     (define %bzip2
+                       #+(and bzip2 (file-append bzip2 "/bin/bzip2")))
+                     (define %xz
+                       #+(and xz (file-append xz "/bin/xz")))
+
+                     (define %libgcrypt
+                       #+(and libgcrypt
+                              (file-append libgcrypt "/lib/libgcrypt")))
+                     (define %libz
+                       #+(and zlib
+                              (file-append zlib "/lib/libz")))
+
+                     (define %nix-instantiate     ;for (guix import snix)
+                       "nix-instantiate")))))
 
-(define guile-bytestructures
-  (package-for-current-guile "guile-bytestructures"
-                             "guile2.0-bytestructures"))
 
-;; The actual build procedure.
-
-(define (top-source-directory)
-  "Return the name of the top-level directory of this source tree."
-  (and=> (assoc-ref (current-source-location) 'filename)
-         (lambda (file)
-           (string-append (dirname file) "/.."))))
+;;;
+;;; 'gexp->script'.
+;;;
+;;; This is our own variant of 'gexp->script' with an extra #:module-path
+;;; parameter, which was unavailable in (guix gexp) until commit
+;;; 1ae16033f34cebe802023922436883867010850f (March 2018.)
+;;;
 
+(define (load-path-expression modules path)
+  "Return as a monadic value a gexp that sets '%load-path' and
+'%load-compiled-path' to point to MODULES, a list of module names.  MODULES
+are searched for in PATH."
+  (mlet %store-monad ((modules  (imported-modules modules
+                                                  #:module-path path))
+                      (compiled (compiled-modules modules
+                                                  #:module-path path)))
+    (return (gexp (eval-when (expand load eval)
+                    (set! %load-path
+                      (cons (ungexp modules) %load-path))
+                    (set! %load-compiled-path
+                      (cons (ungexp compiled)
+                            %load-compiled-path)))))))
+
+(define* (gexp->script name exp
+                       #:key (guile (default-guile))
+                       (module-path %load-path))
+  "Return an executable script NAME that runs EXP using GUILE, with EXP's
+imported modules in its search path."
+  (mlet %store-monad ((set-load-path
+                       (load-path-expression (gexp-modules exp)
+                                             module-path)))
+    (gexp->derivation name
+                      (gexp
+                       (call-with-output-file (ungexp output)
+                         (lambda (port)
+                           ;; Note: that makes a long shebang.  When the store
+                           ;; is /gnu/store, that fits within the 128-byte
+                           ;; limit imposed by Linux, but that may go beyond
+                           ;; when running tests.
+                           (format port
+                                   "#!~a/bin/guile --no-auto-compile~%!#~%"
+                                   (ungexp guile))
+
+                           (write '(ungexp set-load-path) port)
+                           (write '(ungexp exp) port)
+                           (chmod port #o555))))
+                      #:module-path module-path)))
 
+
 (define (date-version-string)
   "Return the current date and hour in UTC timezone, for use as a poor
 person's version identifier."
   ;; XXX: Replace with a Git commit id.
   (date->string (current-date 0) "~Y~m~d.~H"))
 
-(define (matching-guile-2.2)
-  "Return a Guile 2.2 with the same version as the current one or immediately
-older than then current one.  This is so that we do not build ABI-incompatible
-objects.  See <https://bugs.gnu.org/29570>."
-  (let loop ((packages (find-packages-by-name "guile" "2.2"))
-             (best     #f))
-    (match packages
-      (()
-       best)
-      ((head tail ...)
-       (if (string=? (package-version head) (version))
-           head
-           (if best
-               (if (version>? (package-version head) (version))
-                   (loop tail best)
-                   (loop tail head))
-               (loop tail head)))))))
-
-(define (guile-for-build)
-  "Return a derivation for Guile 2.0 or 2.2, whichever matches the currently
-running Guile."
-  (package->derivation (cond-expand
-                         (guile-2.2
-                          (canonical-package (matching-guile-2.2)))
-                         (else
-                          (canonical-package
-                           (specification->package "address@hidden"))))))
+(define* (build-program source version
+                        #:optional (guile-version (effective-version)))
+  "Return a program that computes the derivation to build Guix from SOURCE."
+  (with-imported-modules `(((guix config)
+                            => ,(make-config.scm
+                                 #:libgcrypt
+                                 (specification->package "libgcrypt")))
+                           ,@(delete '(guix config)
+                                     (source-module-closure `((guix store)
+                                                              (guix self)
+                                                              (guix 
derivations)
+                                                              (gnu packages 
bootstrap))
+                                                            (cons source 
%load-path))))
+    (gexp->script "compute-guix-derivation"
+                  #~(begin
+                      (use-modules (ice-9 match))
+
+                      (eval-when (expand load eval)
+                        ;; XXX: This hack allows us to ignore
+                        ;; $GUILE_LOAD_COMPILED_PATH, thereby making sure we
+                        ;; only load our own modules or those of Guile.
+                        (unsetenv "GUIX_PACKAGE_PATH")
+                        (match %load-compiled-path
+                          ((front _ ... sys1 sys2)
+                           (set! %load-compiled-path
+                             (list front sys1 sys2)))
+                          (_ #t)))
+
+                      (define-syntax source
+                        (identifier-syntax
+                         (match (command-line)
+                           ((program source) source))))
+
+                      ;; (gnu packages …) modules are going to be looked up
+                      ;; under SOURCE.
+                      (add-to-load-path source)
+
+                      (use-modules (guix store)
+                                   (guix self)
+                                   (guix derivations))
+
+                      (with-store store
+                        (display "Computing Guix derivation...\n"
+                                 (current-error-port))
+                        (display
+                         (derivation-file-name
+                          (run-with-store store
+                            (guix-derivation source #$version
+                                             #$guile-version))))))
+                  #:module-path (list source))))
 
 ;; The procedure below is our return value.
 (define* (build source
@@ -158,124 +241,24 @@ running Guile."
                 #:rest rest)
   "Return a derivation that unpacks SOURCE into STORE and compiles Scheme
 files."
-  ;; The '%xxxdir' variables were added to (guix config) in July 2016 so we
-  ;; cannot assume that they are defined.  Try to guess their value when
-  ;; they're undefined (XXX: we get an incorrect guess when environment
-  ;; variables such as 'NIX_STATE_DIR' are defined!).
-  (define storedir
-    (if (defined? '%storedir) %storedir %store-directory))
-  (define localstatedir
-    (if (defined? '%localstatedir) %localstatedir (dirname %state-directory)))
-  (define sysconfdir
-    (if (defined? '%sysconfdir) %sysconfdir (dirname %config-directory)))
-
-  (define builder
-    #~(begin
-        (use-modules (guix build pull))
-
-        (letrec-syntax ((maybe-load-path
-                         (syntax-rules ()
-                           ((_ item rest ...)
-                            (let ((tail (maybe-load-path rest ...)))
-                              (if (string? item)
-                                  (cons (string-append item
-                                                       "/share/guile/site/"
-                                                       #$(effective-version))
-                                        tail)
-                                  tail)))
-                           ((_)
-                            '()))))
-          (set! %load-path
-                (append
-                 (maybe-load-path #$guile-json #$guile-ssh
-                                  #$guile-git #$guile-bytestructures)
-                 %load-path)))
-
-        (letrec-syntax ((maybe-load-compiled-path
-                         (syntax-rules ()
-                           ((_ item rest ...)
-                            (let ((tail (maybe-load-compiled-path rest ...)))
-                              (if (string? item)
-                                  (cons (string-append item
-                                                       "/lib/guile/"
-                                                       #$(effective-version)
-                                                       "/site-ccache")
-                                        tail)
-                                  tail)))
-                           ((_)
-                            '()))))
-          (set! %load-compiled-path
-                (append
-                 (maybe-load-compiled-path #$guile-json #$guile-ssh
-                                           #$guile-git #$guile-bytestructures)
-                 %load-compiled-path)))
-
-        ;; XXX: The 'guile-ssh' package prior to Guix commit 92b7258 was
-        ;; broken: libguile-ssh could not be found.  Work around that.
-        ;; FIXME: We want Guile-SSH 0.10.2 or later anyway.
-        #$(if (string-prefix? "0.9." (package-version guile-ssh))
-              #~(setenv "LTDL_LIBRARY_PATH" (string-append #$guile-ssh "/lib"))
-              #t)
-
-        (build-guix #$output #$source
-
-                    #:system #$%system
-                    #:storedir #$storedir
-                    #:localstatedir #$localstatedir
-                    #:sysconfdir #$sysconfdir
-                    #:sbindir (string-append #$guix "/sbin")
-
-                    #:package-name #$%guix-package-name
-                    #:package-version #$version
-                    #:bug-report-address #$%guix-bug-report-address
-                    #:home-page-url #$%guix-home-page-url
-
-                    #:libgcrypt #$libgcrypt
-                    #:zlib #$zlib
-                    #:gzip #$gzip
-                    #:bzip2 #$bzip2
-                    #:xz #$xz
-
-                    ;; XXX: This is not perfect, enabling VERBOSE? means
-                    ;; building a different derivation.
-                    #:debug-port (if #$verbose?
-                                     (current-error-port)
-                                     (%make-void-port "w")))))
-
-  (unless guile-git
-    ;; XXX: Guix before February 2017 lacks a 'guile-git' package altogether.
-    ;; If we try to upgrade anyway, the logic in (guix scripts pull) will not
-    ;; build (guix git), which will leave us with an unusable 'guix pull'.  To
-    ;; avoid that, fail early.
-    (format (current-error-port)
-            "\
-Your installation is too old and lacks a '~a' package.
-Please upgrade to an intermediate version first, for instance with:
-
-  guix pull 
--url=https://git.savannah.gnu.org/cgit/guix.git/snapshot/v0.13.0.tar.gz
-\n"
-            (match (effective-version)
-              ("2.0" "guile2.0-git")
-              (_     "guile-git")))
-    (exit 1))
-
-  (mlet %store-monad ((guile (guile-for-build)))
-    (gexp->derivation "guix-latest" builder
-                      #:modules '((guix build pull)
-                                  (guix build utils)
-                                  (guix build compile)
-
-                                  ;; Closure of (guix modules).
-                                  (guix modules)
-                                  (guix memoization)
-                                  (guix profiling)
-                                  (guix sets))
-
-                      ;; Arrange so that our own (guix build …) modules are
-                      ;; used.
-                      #:module-path (list (top-source-directory))
-
-                      #:guile-for-build guile)))
+  ;; Build the build program and then use it as a trampoline to build from
+  ;; SOURCE.
+  (mlet %store-monad ((build (build-program source version)))
+    (mbegin %store-monad
+      (show-what-to-build* (list build))
+      (built-derivations (list build))
+      (let ((pipe (open-pipe* OPEN_READ
+                              (derivation->output-path build)
+                              source)))
+        (match (get-string-all pipe)
+          ((? eof-object?)
+           (error "build program failed" build))
+          ((? derivation-path? drv)
+           (mbegin %store-monad
+             ((store-lift add-temp-root) drv)
+             (return (read-derivation-from-file drv))))
+          ((? string? str)
+           (error "invalid build result" (list build str))))))))
 
 ;; This file is loaded by 'guix pull'; return it the build procedure.
 build