From edd462ae3e4a01e38cf0dfeed12b716145bc6465 Mon Sep 17 00:00:00 2001
From: Fred Morcos <fred.morcos@open-xchange.com>
Date: Tue, 9 Apr 2024 13:15:30 +0200
Subject: [PATCH] Meson: Add systemd feature support for service files

This moves things around a bit. Moves libsystem detection to
meson/libsystem/meson.build and uses meson/systemd/meson.build for
systemd/systemctl version and feature detection
---
 meson.build                  |  1 +
 meson/libsystemd/meson.build |  9 ++++++
 meson/systemd/meson.build    | 53 ++++++++++++++++++++++++++++++++----
 3 files changed, 57 insertions(+), 6 deletions(-)
 create mode 100644 meson/libsystemd/meson.build

diff --git a/meson.build b/meson.build
index 7cbc150df..686f7abac 100644
--- a/meson.build
+++ b/meson.build
@@ -58,6 +58,7 @@ subdir('meson' / 'dlopen')                  # dlopen
 subdir('meson' / 'verbose-logging')         # Verbose Logging
 subdir('meson' / 'pkcs11')                  # PKCS11
 subdir('meson' / 'gss-tsig')                # GSS-TSIG
+subdir('meson' / 'libsystemd')              # Systemd notification
 subdir('meson' / 'systemd')                 # Systemd and unit file handling
 subdir('meson' / 'code-coverage')           # Code coverage
 subdir('meson' / 'auto-var-init')           # Automatic Variable Initialization
diff --git a/meson/libsystemd/meson.build b/meson/libsystemd/meson.build
new file mode 100644
index 000000000..a4649a4ff
--- /dev/null
+++ b/meson/libsystemd/meson.build
@@ -0,0 +1,9 @@
+opt_systemd = get_option('systemd')
+
+dep_systemd = dependency('libsystemd', required: opt_systemd)
+conf.set('HAVE_SYSTEMD', dep_systemd.found(), description: 'libsystemd')
+summary('libsystemd', dep_systemd.found(), bool_yn: true, section: 'Configuration')
+
+if dep_systemd.found()
+  summary('Lib Version', dep_systemd.version(), section: 'Systemd')
+endif
diff --git a/meson/systemd/meson.build b/meson/systemd/meson.build
index 13b097b7a..3cb011314 100644
--- a/meson/systemd/meson.build
+++ b/meson/systemd/meson.build
@@ -1,9 +1,50 @@
-opt_systemd = get_option('systemd')
+dep_systemd_prog = dependency('systemd', required: false)
+summary('Systemd', dep_systemd_prog.found(), bool_yn: true, section: 'Configuration')
 
-dep_systemd = dependency('libsystemd', required: opt_systemd)
-conf.set('HAVE_SYSTEMD', dep_systemd.found(), description: 'systemd')
-summary('Systemd', dep_systemd.found(), bool_yn: true, section: 'Configuration')
+# Map systemd features to systemd/systemctl version.
+systemd_features = {
+  'private_tmp': 183,
+  'system_call_architectures': 209,
+  'private_devices': 209,
+  'restrict_address_families': 211,
+  'protect_system': 214,
+  'protect_home': 214,
+  'restrict_realtime': 231,
+  'memory_deny_write_execute': 231,
+  'protect_control_groups': 232,
+  'protect_kernel_modules': 232,
+  'protect_kernel_tunables': 232,
+  'remove_ipc': 232,
+  'dynamic_user': 232,
+  'private_users': 232,
+  'protect_system_strict': 232,
+  'restrict_namespaces': 233,
+  'lock_personality': 235,
+  # while SystemCallFilter is technically available starting with 187,
+  # we use the pre-defined call filter sets that have been introduced later.
+  # Initial support for these landed in 231
+  # @filesystem @reboot @swap in 233
+  # @aio, @sync, @chown, @setuid, @memlock, @signal and @timer in 235
+  'system_call_filter': 235,
+  'percent_t': 236,
+  'private_mounts': 239,
+  'with_runtime_dir_env': 240,
+  'protect_hostname': 242,
+  'restrict_suidsgid': 242,
+  'protect_kernel_logs': 244,
+  'protect_clock': 245,
+  'protect_proc': 247,
+  'private_ipc': 248,
+}
 
-if dep_systemd.found()
-  summary('Version', dep_systemd.version(), section: 'Systemd')
+systemd_version = dep_systemd_prog.version()
+foreach feature, version: systemd_features
+  feature_name = 'have_systemd_' + feature
+  feature_value = systemd_version.version_compare('>=' + version.to_string())
+  set_variable(feature_name, feature_value)
+  conf.set(feature_name.to_upper(), feature_value, description: 'systemd feature: ' + feature)
+endforeach
+
+if dep_systemd_prog.found()
+  summary('Version', dep_systemd_prog.version(), section: 'Systemd')
 endif
-- 
2.39.2