image: Add a new API.

Raw disk-images and ISO9660 images are created in a Qemu virtual machine. This
is quite fragile, very slow, and almost unusable without KVM.

For all these reasons, add support for host image generation. This implies the
use new image generation mechanisms.

- Raw disk images: images of partitions are created using tools such as mke2fs
  and mkdosfs depending on the partition file-system type. The partition
  images are then assembled into a final image using genimage.

- ISO9660 images: the ISO root directory is populated within the store. GNU
  xorriso is then called on that directory, in the exact same way as this is
  done in (gnu build vm) module.

Those mechanisms are built upon the new (gnu image) module.

* gnu/image.scm: New file.
* gnu/system/image.scm: New file.
* gnu/build/image: New file.
* gnu/local.mk: Add them.
* gnu/system/vm.scm (system-disk-image): Rename to system-disk-image-in-vm.
* gnu/ci.scm (qemu-jobs): Adapt to new API.
* gnu/tests/install.scm (run-install): Ditto.
* guix/scripts/system.scm (system-derivation-for-action): Ditto.

1 files changed, 76 insertions, 0 deletions

diff --git a/gnu/image.scm b/gnu/image.scm
new file mode 100644
index 0000000000..b05fc69dc5
--- /dev/null
+++ b/gnu/image.scm
@@ -0,0 +1,76 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2020 Mathieu Othacehe <m.othacehe@gmail.com>
+;;;
+;;; 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 (gnu image)
+  #:use-module (guix records)
+  #:export (partition
+            partition?
+            partition-device
+            partition-size
+            partition-file-system
+            partition-label
+            partition-uuid
+            partition-flags
+            partition-initializer
+
+            image
+            image-name
+            image-format
+            image-size
+            image-operating-system
+            image-partitions
+            image-compression?
+            image-volatile-root?
+            image-substitutable?))
+
+
+;;;
+;;; Partition record.
+;;;
+
+(define-record-type* <partition> partition make-partition
+  partition?
+  (device      partition-device (default #f))
+  (size        partition-size)
+  (file-system partition-file-system (default "ext4"))
+  (label       partition-label (default #f))
+  (uuid        partition-uuid (default #f))
+  (flags       partition-flags (default '()))
+  (initializer partition-initializer (default #f)))
+
+
+;;;
+;;; Image record.
+;;;
+
+(define-record-type* <image>
+  image make-image
+  image?
+  (format             image-format) ;symbol
+  (size               image-size  ;size in bytes as integer
+                      (default 'guess))
+  (operating-system   image-operating-system  ;<operating-system>
+                      (default #f))
+  (partitions         image-partitions ;list of <partition>
+                      (default '()))
+  (compression?       image-compression? ;boolean
+                      (default #t))
+  (volatile-root?     image-volatile-root? ;boolean
+                      (default #t))
+  (substitutable?     image-substitutable? ;boolean
+                      (default #t)))