Suggested by Mark H. Weaver.
* gnu/system/shadow.scm (<user-group>)[system?]: New field.
(%base-groups): Introduce 'system-group' macro, and use it.
* gnu/system.scm (user-group->gexp): Pass the 'system?' field.
* guix/build/activation.scm (add-group): Add #:system? and honor it.
(activate-users+groups): Handle the 'system?' field.
* gnu/system/file-systems.scm (%tty-gid): Choose an ID below 1000.
* doc/guix.texi (User Accounts): Document the 'system?' field.
* gnu/system/shadow.scm (<user-account>)[system?]: New field.
* gnu/system.scm (user-account->gexp): Add it.
* guix/build/activation.scm (add-user): Add #:system? parameter and
honor it.
(activate-users+groups): Handle the 'system?' part of user tuples.
Pass it to 'add-user'. Don't create PROFILE-DIR when SYSTEM? is
true.
* gnu/services/dbus.scm (dbus-service): Add 'system?' field for
"messagebus" account.
* gnu/services/base.scm (guix-build-accounts): Likewise.
* gnu/services/avahi.scm (avahi-service): Likewise.
This is a followup to e2fcc23. The /etc/group file would be cleared
when booting.
* guix/build/activation.scm (activate-users+groups)[touch]: Rewrite so
it does not wipe out FILE's contents.
Before that the effect would be to re-create groups at each boot, and
thus remove any members of the groups.
* guix/build/activation.scm (activate-users+groups): Call 'add-group'
only when (getgrname name) fails.
* gnu/system.scm (operating-system-activation-script): New procedure,
containing most of the former 'operating-system-boot-script'.
(operating-system-boot-script): Call it, and 'primitive-load' its
result.
* guix/build/activation.scm (%booted-system): Remove.
(activate-current-system): Remove #:boot? parameter and related code.
* gnu/system.scm (etc-directory): Change default value of #:profile.
Change contents of SHELLS. Use /run/current-system/profile/{s,}bin in
BASHRC.
(operating-system-boot-script)[%modules]: Add (guix build
linux-initrd). Add call to 'activate-current-system' in gexp.
(operating-system-initrd-file, operating-system-grub.cfg): New
procedures.
(operating-system-derivation): Don't build grub.cfg here and remove it
from the file union.
* gnu/system/vm.scm (qemu-image): Remove #:populate.
(operating-system-build-gid, operating-system-default-contents):
Remove.
(system-qemu-image): Remove call to
'operating-system-default-contents'. Use 'operating-system-grub.cfg'
to get grub.cfg. Add GRUB.CFG to #:inputs.
(system-qemu-image/shared-store): Likewise, but don't add GRUB.CFG to
#:inputs.
(system-qemu-image/shared-store-script): Pass --system kernel option.
* guix/build/activation.scm (%booted-system, %current-system): New
variables.
(boot-time-system, activate-current-system): New procedures.
* guix/build/install.scm (evaluate-populate-directive): Add case
for ('directory name uid gid mode).
(directives, populate-root-file-system): New procedures.
* guix/build/vm.scm (initialize-hard-disk): Replace calls to
'evaluate-populate-directive' by a call to
'populate-root-file-system'.
* gnu/services/dmd.scm (dmd-configuration-file): Use
/run/current-system/profile/bin.
* gnu/services/xorg.scm (slim-service): Likewise.
* gnu/system.scm (<operating-system>)[pam-services, setuid-programs]:
New fields.
(etc-directory)[bashrc]: Prepend /run/setuid-programs to $PATH.
(operating-system-etc-directory): Honor
'operating-system-pam-services'.
(%setuid-programs): New variable.
(operating-system-boot-script): Add (guix build utils) to the set of
imported modules. Call 'activate-setuid-programs' in boot script.
* gnu/system/linux.scm (base-pam-services): New procedure.
* guix/build/activation.scm (%setuid-directory): New variable.
(activate-setuid-programs): New procedure.
* build-aux/hydra/demo-os.scm: Add 'pam-services' field.
Ludovic Courtès