Use systemd-sysusers to create user & group

This duplicates the sysusers config from upstream but only installs the
upstream one. The configs should be kept in sync.

We can not use the upstream one as it requires pre-processing that will
only happen at a later time in the build process.

See: https://docs.fedoraproject.org/en-US/packaging-guidelines/UsersAndGroups/#_dynamic_allocation

https://src.fedoraproject.org/rpms/flatpak/pull-request/8

flatpak.spec

@@ -4,7 +4,7 @@
 
 Name:           flatpak
 Version:        1.13.2
-Release:        2%{?dist}
+Release:        3%{?dist}
 Summary:        Application deployment framework for desktop apps
 
 License:        LGPLv2+
@@ -16,6 +16,10 @@ Source0:        https://github.com/flatpak/flatpak/releases/download/%{version}/
 Source1:        flatpak-add-fedora-repos.service
 %endif
 
+# systemd-sysusers config. Only used for the %%pre macro. Must be kept in sync
+# with the config from upstream sources.
+Source2:        flatpak.sysusers.conf
+
 Patch0:         flatpak-selinux-permissions.patch
 
 BuildRequires:  pkgconfig(appstream) >= %{appstream_version}
@@ -44,6 +48,7 @@ BuildRequires:  gpgme-devel
 BuildRequires:  libcap-devel
 BuildRequires:  python3-pyparsing
 BuildRequires:  systemd
+BuildRequires:  systemd-rpm-macros
 BuildRequires:  /usr/bin/xdg-dbus-proxy
 BuildRequires:  /usr/bin/xmlto
 BuildRequires:  /usr/bin/xsltproc
@@ -158,11 +163,7 @@ install -D -t %{buildroot}%{_unitdir} %{SOURCE1}
 %find_lang %{name}
 
 %pre
-getent group flatpak >/dev/null || groupadd -r flatpak
-getent passwd flatpak >/dev/null || \
-    useradd -r -g flatpak -d / -s /sbin/nologin \
-     -c "User for flatpak system helper" flatpak
-exit 0
+%sysusers_create_compat %{SOURCE2}
 
 
 %if 0%{?fedora}
@@ -227,7 +228,7 @@ fi
 %{_sysconfdir}/dbus-1/system.d/org.freedesktop.Flatpak.SystemHelper.conf
 %{_sysconfdir}/flatpak/remotes.d
 %{_sysconfdir}/profile.d/flatpak.sh
-%{_sysusersdir}/flatpak.conf
+%{_sysusersdir}/%{name}.conf
 %{_unitdir}/flatpak-system-helper.service
 %{_userunitdir}/flatpak-oci-authenticator.service
 %{_userunitdir}/flatpak-portal.service
@@ -267,6 +268,9 @@ fi
 
 
 %changelog
+* Tue May 17 2022 Timothée Ravier <tim@siosm.fr> - 1.13.2-3
+- Use sysusers_create_compat macro to create user & group.
+
 * Tue Apr 12 2022 Debarshi Ray <rishi@fedoraproject.org> - 1.13.2-2
 - Avoid SELinux denials caused by read access to /etc/passwd, watching files
   inside /usr/libexec and read access to /var/lib/flatpak

flatpak.sysusers.conf

@@ -0,0 +1 @@
+u flatpak - "Flatpak system helper" -