libnm: use "libnm-systemd-shared.a" in "libnm-core.la" (and "libnm.so")

It's not yet used, but it will be. We will need nm_sd_utils_unbase64mem()
to strictly validate WireGuard settings, which contain keys in base64 encoding.

Note that we also need a stub implementation for logging. This will do
nothing for all logging from "libnm-systemd-shared.a". This makes
sense because "libnm.so" as a library should not log directly. Also,
"libnm.so" will only use a small portion of "libnm-systemd-shared.a" which
doesn't log anything. Thus this code is unused and dropped by the linker
with "--gc-sections".

Makefile.am

@@ -940,6 +940,8 @@ nodist_libnm_core_tests_test_general_SOURCES = \
 
 libnm_core_tests_ldadd = \
 	libnm-core/libnm-core.la \
+	shared/systemd/libnm-systemd-shared.la \
+	shared/systemd/libnm-systemd-logging-stub.la \
 	shared/nm-utils/libnm-utils-base.la \
 	$(libnm_crypto_lib) \
 	$(GLIB_LIBS)
@@ -1191,6 +1193,8 @@ EXTRA_libnm_libnm_la_DEPENDENCIES = \
 
 libnm_libnm_la_LIBADD = \
 	libnm/libnm-utils.la \
+	shared/systemd/libnm-systemd-shared.la \
+	shared/systemd/libnm-systemd-logging-stub.la \
 	shared/nm-utils/libnm-utils-udev.la \
 	$(DL_LIBS) \
 	$(GLIB_LIBS) \
@@ -1357,6 +1361,8 @@ libnm_tests_cppflags = \
 
 libnm_tests_ldadd = \
 	libnm/libnm.la \
+	shared/systemd/libnm-systemd-shared.la \
+	shared/systemd/libnm-systemd-logging-stub.la \
 	$(GLIB_LIBS)
 
 libnm_tests_ldflags = \
@@ -1517,6 +1523,22 @@ libsystemd_libadd = \
 	$(CODE_COVERAGE_LDFLAGS) \
 	$(NULL)
 
+noinst_LTLIBRARIES += shared/systemd/libnm-systemd-logging-stub.la
+
+shared_systemd_libnm_systemd_logging_stub_la_CPPFLAGS = \
+	$(libsystemd_cppflags) \
+	-DNETWORKMANAGER_COMPILATION=NM_NETWORKMANAGER_COMPILATION_SYSTEMD_SHARED \
+	-DG_LOG_DOMAIN=\""libnm"\" \
+	$(NULL)
+
+shared_systemd_libnm_systemd_logging_stub_la_SOURCES = \
+	shared/systemd/nm-logging-stub.c \
+	$(NULL)
+
+shared_systemd_libnm_systemd_logging_stub_la_LIBADD = \
+	$(libsystemd_libadd) \
+	$(NULL)
+
 noinst_LTLIBRARIES += shared/systemd/libnm-systemd-shared.la
 
 shared_systemd_libnm_systemd_shared_la_CPPFLAGS = \
@@ -2105,6 +2127,7 @@ src_initrd_nm_initrd_generator_LDADD = \
 	libnm-core/libnm-core.la \
 	src/initrd/libnmi-core.la \
 	src/libNetworkManagerBase.la \
+	shared/systemd/libnm-systemd-shared.la \
 	shared/nm-utils/libnm-utils-base.la \
 	$(GLIB_LIBS) \
 	$(NULL)

libnm-core/meson.build

@@ -200,6 +200,7 @@ nm_core_dep = declare_dependency(
   dependencies: [
     shared_dep,
     shared_c_siphash_dep,
+    libnm_systemd_shared_dep,
   ],
 )
 

libnm-core/tests/meson.build

@@ -33,7 +33,10 @@ foreach test_unit: test_units
   exe = executable(
     'libnm-core-' + test_unit,
     [test_unit + '.c'] + enum,
-    dependencies: nm_core_dep,
+    dependencies: [
+      nm_core_dep,
+      libnm_systemd_shared_no_logging_dep,
+    ],
     c_args: [
         '-DNETWORKMANAGER_COMPILATION_TEST',
         '-DNETWORKMANAGER_COMPILATION=NM_NETWORKMANAGER_COMPILATION_LIBNM_CORE',

libnm/meson.build

@@ -147,6 +147,7 @@ deps = [
   libudev_dep,
   shared_dep,
   uuid_dep,
+  libnm_systemd_shared_no_logging_dep,
 ]
 
 linker_script = join_paths(meson.current_source_dir(), 'libnm.ver')

libnm/tests/meson.build

@@ -20,6 +20,7 @@ foreach test_unit: test_units
     dependencies: [
       libnm_dep,
       nm_core_dep,
+      libnm_systemd_shared_no_logging_dep,
     ],
     c_args: cflags,
     link_with: test_unit[1],

shared/meson.build

@@ -207,3 +207,28 @@ libnm_systemd_shared_dep = declare_dependency(
     libnm_systemd_shared,
   ],
 )
+
+libnm_systemd_logging_stub = static_library(
+  'nm-systemd-logging-stub',
+  sources: files(
+    'systemd/nm-logging-stub.c',
+  ),
+  include_directories: include_directories(
+    'systemd/sd-adapt-shared',
+    'systemd/src/basic',
+  ),
+  dependencies: shared_dep,
+  c_args: [
+    '-DNETWORKMANAGER_COMPILATION=NM_NETWORKMANAGER_COMPILATION_SYSTEMD_SHARED',
+    '-DG_LOG_DOMAIN="libnm"',
+  ],
+)
+
+libnm_systemd_shared_no_logging_dep = declare_dependency(
+  dependencies: [
+    libnm_systemd_shared_dep,
+  ],
+  link_with: [
+    libnm_systemd_logging_stub,
+  ],
+)

shared/systemd/nm-logging-stub.c

@@ -0,0 +1,45 @@
+/*
+ * 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., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ * Copyright 2018 Red Hat, Inc.
+ */
+
+#include "nm-default.h"
+
+#include "nm-utils/nm-logging-fwd.h"
+
+/*****************************************************************************/
+
+gboolean
+_nm_log_enabled (NMLogLevel level,
+                 NMLogDomain domain)
+{
+	return FALSE;
+}
+
+void
+_nm_log_impl (const char *file,
+              guint line,
+              const char *func,
+              NMLogLevel level,
+              NMLogDomain domain,
+              int error,
+              const char *ifname,
+              const char *con_uuid,
+              const char *fmt,
+              ...)
+{
+}

src/systemd/meson.build

@@ -38,7 +38,6 @@ libnm_systemd_core = static_library(
     )
   ],
   dependencies: [
-    libnm_systemd_shared_dep,
     nm_core_dep,
   ],
   c_args: [