Add --with-dracut

This installs a Dracut module which parses the ostree= kernel command
line argument, and if given, sets up the OS/ at /sysroot, which
systemd's switch-root then moves into.  This only works if dracut is
configured to use systemd itself.

src/dracut/module-setup.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
+# ex: ts=8 sw=4 sts=4 et filetype=sh
+#
+# Copyright (C) 2013 Colin Walters <walters@verbum.org>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the
+# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+# Boston, MA 02111-1307, USA.
+
+check() {
+    if [[ -x $systemdutildir/systemd ]] && [[ -x /usr/sbin/ostree-prepare-root ]]; then
+       return 255
+    fi
+
+    return 1
+}
+
+depends() {
+    return 0
+}
+
+install() {
+    dracut_install ostree-prepare-root
+    inst_simple "$moddir/ostree-prepare-root.service" "${systemdsystemunitdir}/ostree-prepare-root.service"
+    mkdir -p "${initdir}${systemdsystemconfdir}/initrd-switch-root.target.wants"
+    ln_r "${systemdsystemunitdir}/ostree-prepare-root.service" \
+        "${systemdsystemconfdir}/initrd-switch-root.target.wants/ostree-prepare-root.service"
+}
+

src/dracut/ostree-prepare-root.service

@@ -0,0 +1,32 @@
+# Copyright (C) 2013 Colin Walters <walters@verbum.org>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the
+# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+# Boston, MA 02111-1307, USA.
+
+[Unit]
+Description=OSTree Prepare OS/
+DefaultDependencies=no
+ConditionKernelCommandLine=ostree
+ConditionPathExists=/etc/initrd-release
+OnFailure=emergency.service
+After=initrd-switch-root.target
+Before=initrd-switch-root.service
+
+[Service]
+Type=oneshot
+ExecStart=/usr/sbin/ostree-prepare-root /sysroot
+StandardInput=null
+StandardOutput=syslog
+StandardError=syslog+console

src/dracut/ostree.conf

@@ -0,0 +1,18 @@
+# Copyright (C) 2013 Colin Walters <walters@verbum.org>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the
+# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+# Boston, MA 02111-1307, USA.
+
+add_dracutmodules+="ostree"