From 53f79e125d5614d899bc3489d00850ddf66c45d7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Tue, 5 Mar 2019 16:19:40 +0100
Subject: [PATCH] meson: use a convenience library for the sources shared
 between core/ and the outside

This avoids double compilation. Those files are tiny, so it doesn't save time,
but we avoid repeated warnings and errors, and it's generally cleaner to it
this way.

The number of commands in 'ninja -C build clean && ninja -C build' drops from
1462 to 1455 for me.
---
 meson.build          | 28 ++++++++++------------------
 src/core/meson.build | 29 +++++++++++++++++++++--------
 src/test/meson.build |  5 ++---
 3 files changed, 33 insertions(+), 29 deletions(-)

diff --git a/meson.build b/meson.build
index f2b975abc5..5597fe9236 100644
--- a/meson.build
+++ b/meson.build
@@ -1713,9 +1713,9 @@ executable('systemd-run-generator',
 
 executable('systemd-fstab-generator',
            'src/fstab-generator/fstab-generator.c',
-           'src/core/mount-setup.c',
            include_directories : includes,
-           link_with : [libshared],
+           link_with : [libcore_shared,
+                        libshared],
            install_rpath : rootlibexecdir,
            install : true,
            install_dir : systemgeneratordir)
@@ -2353,20 +2353,18 @@ endif
 
 executable('systemd-remount-fs',
            'src/remount-fs/remount-fs.c',
-           'src/core/mount-setup.c',
-           'src/core/mount-setup.h',
            include_directories : includes,
-           link_with : [libshared],
+           link_with : [libcore_shared,
+                        libshared],
            install_rpath : rootlibexecdir,
            install : true,
            install_dir : rootlibexecdir)
 
 executable('systemd-machine-id-setup',
            'src/machine-id-setup/machine-id-setup-main.c',
-           'src/core/machine-id-setup.c',
-           'src/core/machine-id-setup.h',
            include_directories : includes,
-           link_with : [libshared],
+           link_with : [libcore_shared,
+                        libshared],
            install_rpath : rootlibexecdir,
            install : true,
            install_dir : rootbindir)
@@ -2678,12 +2676,9 @@ public_programs += exe
 
 executable('systemd-shutdown',
            systemd_shutdown_sources,
-           'src/core/mount-setup.c',
-           'src/core/mount-setup.h',
-           'src/core/killall.c',
-           'src/core/killall.h',
            include_directories : includes,
-           link_with : [libshared],
+           link_with : [libcore_shared,
+                        libshared],
            dependencies : [libmount],
            install_rpath : rootlibexecdir,
            install : true,
@@ -2724,12 +2719,9 @@ endif
 
 exe = executable('systemd-nspawn',
                  systemd_nspawn_sources,
-                 'src/core/mount-setup.c', # FIXME: use a variable?
-                 'src/core/mount-setup.h',
-                 'src/core/loopback-setup.c',
-                 'src/core/loopback-setup.h',
                  include_directories : includes,
-                 link_with : [libnspawn_core,
+                 link_with : [libcore_shared,
+                              libnspawn_core,
                               libshared],
                  dependencies : [libblkid],
                  install_rpath : rootlibexecdir,
diff --git a/src/core/meson.build b/src/core/meson.build
index 6f387c4796..2e58146d1f 100644
--- a/src/core/meson.build
+++ b/src/core/meson.build
@@ -1,5 +1,16 @@
 # SPDX-License-Identifier: LGPL-2.1+
 
+libcore_shared_sources = '''
+        killall.c
+        killall.h
+        loopback-setup.c
+        loopback-setup.h
+        machine-id-setup.c
+        machine-id-setup.h
+        mount-setup.c
+        mount-setup.h
+'''.split()
+
 libcore_la_sources = '''
         audit-fd.c
         audit-fd.h
@@ -69,8 +80,6 @@ libcore_la_sources = '''
         job.h
         kill.c
         kill.h
-        killall.c
-        killall.h
         kmod-setup.c
         kmod-setup.h
         load-dropin.c
@@ -79,14 +88,8 @@ libcore_la_sources = '''
         load-fragment.h
         locale-setup.c
         locale-setup.h
-        loopback-setup.c
-        loopback-setup.h
-        machine-id-setup.c
-        machine-id-setup.h
         manager.c
         manager.h
-        mount-setup.c
-        mount-setup.h
         mount.c
         mount.h
         namespace.c
@@ -144,12 +147,22 @@ load_fragment_gperf_nulstr_c = custom_target(
         command : [awk, '-f', '@INPUT0@', '@INPUT1@'],
         capture : true)
 
+# A convenience library to share code with other binaries:
+# systemd-shutdown, systemd-remount-fs, systemd-machine-id-setup, …
+libcore_shared = static_library(
+        'core-shared',
+        libcore_shared_sources,
+        include_directories : includes,
+        dependencies : [versiondep,
+                        libmount])
+
 libcore = static_library(
         'core',
         libcore_la_sources,
         load_fragment_gperf_c,
         load_fragment_gperf_nulstr_c,
         include_directories : includes,
+        link_whole : libcore_shared,
         dependencies : [versiondep,
                         threads,
                         librt,
diff --git a/src/test/meson.build b/src/test/meson.build
index e43f119230..19f7a1e486 100644
--- a/src/test/meson.build
+++ b/src/test/meson.build
@@ -714,11 +714,10 @@ tests += [
          'ENABLE_NSS', 'manual'],
 
         [['src/test/test-umount.c',
-          'src/core/mount-setup.c',
-          'src/core/mount-setup.h',
           'src/shutdown/umount.c',
           'src/shutdown/umount.h'],
-         [],
+         [libcore_shared,
+          libshared],
          [libmount]],
 
         [['src/test/test-bus-util.c'],