store-copy: 'populate-store' can optionally deduplicate files.

Until now deduplication was performed as an additional pass after
copying files, which involve re-traversing all the files that had just
been copied.

* guix/store/deduplication.scm (copy-file/deduplicate): New procedure.
* tests/store-deduplication.scm ("copy-file/deduplicate"): New test.
* guix/build/store-copy.scm (populate-store): Add #:deduplicate?
parameter and honor it.
* tests/gexp.scm ("gexp->derivation, store copy"): Pass #:deduplicate? #f
to 'populate-store'.
* gnu/build/image.scm (initialize-root-partition): Pass #:deduplicate?
to 'populate-store'.  Pass #:deduplicate? #f to 'register-closure'.
* gnu/build/vm.scm (root-partition-initializer): Likewise.
* gnu/build/install.scm (populate-single-profile-directory): Pass
 #:deduplicate? #f to 'populate-store'.
* gnu/build/linux-initrd.scm (build-initrd): Likewise.
* guix/scripts/pack.scm (self-contained-tarball)[import-module?]: New
procedure.
[build]: Pass it as an argument to 'source-module-closure'.
* guix/scripts/pack.scm (squashfs-image)[build]: Wrap in
'with-extensions'.
* gnu/system/linux-initrd.scm (expression->initrd)[import-module?]: New
procedure.
[builder]: Pass it to 'source-module-closure'.
* gnu/system/install.scm (cow-store-service-type)[import-module?]: New
procedure.  Pass it to 'source-module-closure'.

2 files changed, 19 insertions, 3 deletions

diff --git a/gnu/system/install.scm b/gnu/system/install.scm
index a6b9e3d9523..e7534634739 100644
--- a/gnu/system/install.scm
+++ b/gnu/system/install.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2015 Mark H Weaver <mhw@netris.org>
 ;;; Copyright © 2016 Andreas Enge <andreas@enge.fr>
 ;;; Copyright © 2017 Marius Bakke <mbakke@fastmail.com>
@@ -176,6 +176,13 @@ manual."
   (shepherd-service-type
    'cow-store
    (lambda _
+     (define (import-module? module)
+       ;; Since we don't use deduplication support in 'populate-store', don't
+       ;; import (guix store deduplication) and its dependencies, which
+       ;; includes Guile-Gcrypt.
+       (and (guix-module-name? module)
+            (not (equal? module '(guix store deduplication)))))
+
      (shepherd-service
       (requirement '(root-file-system user-processes))
       (provision '(cow-store))
@@ -190,7 +197,8 @@ the given target.")
                  ,@%default-modules))
       (start
        (with-imported-modules (source-module-closure
-                               '((gnu build install)))
+                               '((gnu build install))
+                               #:select? import-module?)
          #~(case-lambda
              ((target)
               (mount-cow-store target #$%backing-directory)
diff --git a/gnu/system/linux-initrd.scm b/gnu/system/linux-initrd.scm
index 4fb1d863c9d..c6ba9bb5605 100644
--- a/gnu/system/linux-initrd.scm
+++ b/gnu/system/linux-initrd.scm
@@ -76,12 +76,20 @@ the derivations referenced by EXP are automatically copied to the initrd."
   (define init
     (program-file "init" exp #:guile guile))
 
+  (define (import-module? module)
+    ;; Since we don't use deduplication support in 'populate-store', don't
+    ;; import (guix store deduplication) and its dependencies, which includes
+    ;; Guile-Gcrypt.  That way we can run tests with '--bootstrap'.
+    (and (guix-module-name? module)
+         (not (equal? module '(guix store deduplication)))))
+
   (define builder
     ;; Do not use "guile-zlib" extension here, otherwise it would drag the
     ;; non-static "zlib" package to the initrd closure.  It is not needed
     ;; anyway because the modules are stored uncompressed within the initrd.
     (with-imported-modules (source-module-closure
-                            '((gnu build linux-initrd)))
+                            '((gnu build linux-initrd))
+                            #:select? import-module?)
       #~(begin
           (use-modules (gnu build linux-initrd))