dbus: add infrastructure for changing multiple properties at once on units and hook some cgroup attributes up to it

This introduces two bus calls to make runtime changes to selected bus
properties, optionally with persistence.

This currently hooks this up only for three cgroup atributes, but this
brings the infrastructure to add more changable attributes.

This allows setting multiple attributes at once, and takes an array
rather than a dictionary of properties, in order to implement simple
resetting of lists using the same approach as when they are sourced from
unit files. This means, that list properties are appended to by this
call, unless they are first reset via assigning the empty list.

1 files changed, 16 insertions, 9 deletions

diff --git a/src/core/unit.c b/src/core/unit.c
index 0dcf85b5e0..be554dac20 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -2642,7 +2642,7 @@ CGroupContext *unit_get_cgroup_context(Unit *u) {
         return (CGroupContext*) ((uint8_t*) u + offset);
 }
 
-static int drop_in_file(Unit *u, bool runtime, const char *name, char **_p, char **_q) {
+static int drop_in_file(Unit *u, UnitSetPropertiesMode mode, const char *name, char **_p, char **_q) {
         char *p, *q;
         int r;
 
@@ -2650,8 +2650,9 @@ static int drop_in_file(Unit *u, bool runtime, const char *name, char **_p, char
         assert(name);
         assert(_p);
         assert(_q);
+        assert(mode & (UNIT_PERSISTENT|UNIT_RUNTIME));
 
-        if (u->manager->running_as == SYSTEMD_USER && runtime)
+        if (u->manager->running_as == SYSTEMD_USER && !(mode & UNIT_PERSISTENT))
                 return -ENOTSUP;
 
         if (!filename_is_safe(name))
@@ -2667,10 +2668,10 @@ static int drop_in_file(Unit *u, bool runtime, const char *name, char **_p, char
                         return -ENOENT;
 
                 p = strjoin(c, "/", u->id, ".d", NULL);
-        } else  if (runtime)
-                p = strjoin("/run/systemd/system/", u->id, ".d", NULL);
-        else
+        } else  if (mode & UNIT_PERSISTENT)
                 p = strjoin("/etc/systemd/system/", u->id, ".d", NULL);
+        else
+                p = strjoin("/run/systemd/system/", u->id, ".d", NULL);
         if (!p)
                 return -ENOMEM;
 
@@ -2685,13 +2686,16 @@ static int drop_in_file(Unit *u, bool runtime, const char *name, char **_p, char
         return 0;
 }
 
-int unit_write_drop_in(Unit *u, bool runtime, const char *name, const char *data) {
+int unit_write_drop_in(Unit *u, UnitSetPropertiesMode mode, const char *name, const char *data) {
         _cleanup_free_ char *p = NULL, *q = NULL;
         int r;
 
         assert(u);
 
-        r = drop_in_file(u, runtime, name, &p, &q);
+        if (!(mode & (UNIT_PERSISTENT|UNIT_RUNTIME)))
+                return 0;
+
+        r = drop_in_file(u, mode, name, &p, &q);
         if (r < 0)
                 return r;
 
@@ -2699,13 +2703,16 @@ int unit_write_drop_in(Unit *u, bool runtime, const char *name, const char *data
         return write_string_file_atomic_label(q, data);
 }
 
-int unit_remove_drop_in(Unit *u, bool runtime, const char *name) {
+int unit_remove_drop_in(Unit *u, UnitSetPropertiesMode mode, const char *name) {
         _cleanup_free_ char *p = NULL, *q = NULL;
         int r;
 
         assert(u);
 
-        r = drop_in_file(u, runtime, name, &p, &q);
+        if (!(mode & (UNIT_PERSISTENT|UNIT_RUNTIME)))
+                return 0;
+
+        r = drop_in_file(u, mode, name, &p, &q);
         if (unlink(q) < 0)
                 r = -errno;
         else