install: when a template unit is instantiated via a /usr symlink, consider it enabled

If a unit foobar@.service stored below /usr is instantiated via a
symlink foobar@quux.service also below /usr, then we should consider the
instance statically enabled, while the template itself should continue
to be considered enabled/disabled/static depending on its [Install]
section.

In order to implement this we'll now look for enablement symlinks in all
unit search paths, not just in the config and runtime dirs.

Fixes: #5136

1 files changed, 23 insertions, 0 deletions

diff --git a/src/test/test-install-root.c b/src/test/test-install-root.c
index d0bc8004f3..575401cb91 100644
--- a/src/test/test-install-root.c
+++ b/src/test/test-install-root.c
@@ -736,6 +736,28 @@ static void test_preset_order(const char *root) {
         assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "prefix-2.service", &state) >= 0 && state == UNIT_FILE_DISABLED);
 }
 
+static void test_static_instance(const char *root) {
+        UnitFileState state;
+        const char *p;
+
+        assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "static-instance@.service", &state) == -ENOENT);
+        assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "static-instance@foo.service", &state) == -ENOENT);
+
+        p = strjoina(root, "/usr/lib/systemd/system/static-instance@.service");
+        assert_se(write_string_file(p,
+                                    "[Install]\n"
+                                    "WantedBy=multi-user.target\n", WRITE_STRING_FILE_CREATE) >= 0);
+
+        assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "static-instance@.service", &state) >= 0 && state == UNIT_FILE_DISABLED);
+        assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "static-instance@foo.service", &state) >= 0 && state == UNIT_FILE_DISABLED);
+
+        p = strjoina(root, "/usr/lib/systemd/system/static-instance@foo.service");
+        assert_se(symlink("static-instance@.service", p) >= 0);
+
+        assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "static-instance@.service", &state) >= 0 && state == UNIT_FILE_DISABLED);
+        assert_se(unit_file_get_state(UNIT_FILE_SYSTEM, root, "static-instance@foo.service", &state) >= 0 && state == UNIT_FILE_STATIC);
+}
+
 int main(int argc, char *argv[]) {
         char root[] = "/tmp/rootXXXXXX";
         const char *p;
@@ -766,6 +788,7 @@ int main(int argc, char *argv[]) {
         test_preset_and_list(root);
         test_preset_order(root);
         test_revert(root);
+        test_static_instance(root);
 
         assert_se(rm_rf(root, REMOVE_ROOT|REMOVE_PHYSICAL) >= 0);