Create separate standalone packages for tmpfiles and sysusers

These packages include binaries that link to a static version of
libsystemd-shared, so they don't depend on the systemd-libs package at
runtime.

These packages are intended to expose systemd-tmpfiles and systemd-sysusers
to non-systemd systems, such as container images.

Note that static linking only pulls in the small subset of functions from
libsystemd-shared that are actually used by the binaries, so the total size of
a statically linked binary is much smaller than the sum of the shared binary
with the shared library. The resulting binaries on an x86_64 build have 272KB
(tmpfiles) and 180KB (sysusers).

This commit relies on the -Dstandalone-binaries=true build configuration that
was pushed upstream in PR 16061 and released in systemd v246.

split-files.py

@@ -21,9 +21,11 @@ o_pam = open('.file-list-pam', 'w')
 o_rpm_macros = open('.file-list-rpm-macros', 'w')
 o_devel = open('.file-list-devel', 'w')
 o_container = open('.file-list-container', 'w')
+o_networkd = open('.file-list-networkd', 'w')
 o_remote = open('.file-list-remote', 'w')
 o_tests = open('.file-list-tests', 'w')
-o_networkd = open('.file-list-networkd', 'w')
+o_standalone_tmpfiles = open('.file-list-standalone-tmpfiles', 'w')
+o_standalone_sysusers = open('.file-list-standalone-sysusers', 'w')
 o_rest = open('.file-list-rest', 'w')
 for file in files(buildroot):
     n = file.path[1:]
@@ -112,6 +114,13 @@ for file in files(buildroot):
                        /modprobe.d
     ''', n, re.X):
         o = o_udev
+    elif n.endswith('.standalone'):
+        if 'tmpfiles' in n:
+            o = o_standalone_tmpfiles
+        elif 'sysusers' in n:
+            o = o_standalone_sysusers
+        else:
+            assert False, 'Found .standalone not belonging to known packages'
     else:
         o = o_rest
 

systemd.spec

@@ -334,6 +334,24 @@ License:       LGPLv2+
 "Installed tests" that are usually run as part of the build system.
 They can be useful to test systemd internals.
 
+%package standalone-tmpfiles
+Summary:       Standalone tmpfiles binary for use in non-systemd systems
+RemovePathPostfixes: .standalone
+
+%description standalone-tmpfiles
+Standalone tmpfiles binary with no dependencies on the systemd-shared library
+or other libraries from systemd-libs. This package conflicts with the main
+systemd package and is meant for use in non-systemd systems.
+
+%package standalone-sysusers
+Summary:       Standalone sysusers binary for use in non-systemd systems
+RemovePathPostfixes: .standalone
+
+%description standalone-sysusers
+Standalone sysusers binary with no dependencies on the systemd-shared library
+or other libraries from systemd-libs. This package conflicts with the main
+systemd package and is meant for use in non-systemd systems.
+
 %prep
 %autosetup -n %{?commit:%{name}%{?stable:-stable}-%{commit}}%{!?commit:%{name}%{?stable:-stable}-%{github_version}} -p1
 
@@ -388,6 +406,7 @@ CONFIGURE_OPTS=(
         -Dtpm=true
         -Dhwdb=true
         -Dsysusers=true
+        -Dstandalone-binaries=true
         -Ddefault-kill-user-processes=false
         -Dtests=unsafe
         -Dinstall-tests=true
@@ -829,7 +848,15 @@ fi
 
 %files tests -f .file-list-tests
 
+%files standalone-tmpfiles -f .file-list-standalone-tmpfiles
+
+%files standalone-sysusers -f .file-list-standalone-sysusers
+
 %changelog
+* Thu Sep 24 2020 Filipe Brandenburger <filbranden@gmail.com> - 246.6-2
+- Build a package with standalone binaries for non-systemd systems.
+  For now, only systemd-sysusers is included.
+
 * Thu Sep 24 2020 Christian Glombek <lorbus@fedoraproject.org> - 246.6-2
 - Split out networkd sub-package and add to main package as recommended dependency