sd-bus: add sd_bus_close_unref() helper

It's similar to sd_bus_flush_close_unref() but doesn't do the flushing.
This is useful since this will still discnnect the connection properly
but not synchronously wait for the peer to take our messages.

Primary usecase is within _cleanup_() expressions where synchronously
waiting on the peer is not OK.

man/sd_bus_new.xml

@@ -23,6 +23,8 @@
     <refname>sd_bus_ref</refname>
     <refname>sd_bus_unref</refname>
     <refname>sd_bus_unrefp</refname>
+    <refname>sd_bus_close_unref</refname>
+    <refname>sd_bus_close_unrefp</refname>
     <refname>sd_bus_flush_close_unref</refname>
     <refname>sd_bus_flush_close_unrefp</refname>
 
@@ -49,8 +51,8 @@
       </funcprototype>
 
       <funcprototype>
-        <funcdef>void <function>sd_bus_unrefp</function></funcdef>
-        <paramdef>sd_bus **<parameter>busp</parameter></paramdef>
+        <funcdef>sd_bus *<function>sd_bus_close_unref</function></funcdef>
+        <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
       </funcprototype>
 
       <funcprototype>
@@ -58,6 +60,16 @@
         <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
       </funcprototype>
 
+      <funcprototype>
+        <funcdef>void <function>sd_bus_unrefp</function></funcdef>
+        <paramdef>sd_bus **<parameter>busp</parameter></paramdef>
+      </funcprototype>
+
+      <funcprototype>
+        <funcdef>void <function>sd_bus_close_unrefp</function></funcdef>
+        <paramdef>sd_bus **<parameter>busp</parameter></paramdef>
+      </funcprototype>
+
       <funcprototype>
         <funcdef>void <function>sd_bus_flush_close_unrefp</function></funcdef>
         <paramdef>sd_bus **<parameter>busp</parameter></paramdef>
@@ -124,17 +136,25 @@
     execute no operation if <emphasis>that</emphasis> is <constant>NULL</constant>.
     </para>
 
-    <para><function>sd_bus_flush_close_unref()</function> is similar to <function>sd_bus_unref()</function>, but first
-    executes <citerefentry><refentrytitle>sd_bus_flush</refentrytitle><manvolnum>3</manvolnum></citerefentry> as well
-    as <citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>, ensuring that
-    any pending messages are properly flushed out before the reference to the connection is dropped and possibly the
-    object freed. This call is particularly useful immediately before exiting from a program as it ensures that any
-    pending outgoing messages are written out, and unprocessed but queued incoming messages released before the
-    connection is terminated and released.</para>
+    <para><function>sd_bus_close_unref()</function> is similar to <function>sd_bus_unref()</function>, but
+    first executes
+    <citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+    ensuring that the connection is terminated before the reference to the connection is dropped and possibly
+    the object freed.</para>
 
-    <para><function>sd_bus_flush_close_unrefp()</function> is similar to
-    <function>sd_bus_flush_close_unref()</function>, but may be used in GCC's and LLVM's Clean-up Variable Attribute,
-    see above.</para>
+    <para><function>sd_bus_flush_close_unref()</function> is similar to <function>sd_bus_unref()</function>,
+    but first executes
+    <citerefentry><refentrytitle>sd_bus_flush</refentrytitle><manvolnum>3</manvolnum></citerefentry> as well
+    as <citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+    ensuring that any pending messages are synchronously flushed out before the reference to the connection
+    is dropped and possibly the object freed. This call is particularly useful immediately before exiting
+    from a program as it ensures that any pending outgoing messages are written out, and unprocessed but
+    queued incoming messages released before the connection is terminated and released.</para>
+
+    <para><function>sd_bus_close_unrefp()</function> is similar to
+    <function>sd_bus_close_unref()</function>, but may be used in GCC's and LLVM's Clean-up Variable
+    Attribute, see above. Similarly, <function>sd_bus_flush_close_unrefp()</function> is similar to
+    <function>sd_bus_flush_close_unref()</function>.</para>
   </refsect1>
 
   <refsect1>

src/core/dbus.c

@@ -611,7 +611,7 @@ static int bus_setup_disconnected_match(Manager *m, sd_bus *bus) {
 }
 
 static int bus_on_connection(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
-        _cleanup_(sd_bus_unrefp) sd_bus *bus = NULL;
+        _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL;
         _cleanup_close_ int nfd = -1;
         Manager *m = userdata;
         sd_id128_t id;

src/libsystemd/libsystemd.sym

@@ -671,3 +671,8 @@ global:
         sd_event_source_get_floating;
         sd_event_source_set_floating;
 } LIBSYSTEMD_239;
+
+LIBSYSTEMD_241 {
+global:
+        sd_bus_close_unref;
+} LIBSYSTEMD_240;

src/libsystemd/sd-bus/sd-bus.c

@@ -1556,17 +1556,24 @@ _public_ void sd_bus_close(sd_bus *bus) {
         bus_close_inotify_fd(bus);
 }
 
+_public_ sd_bus *sd_bus_close_unref(sd_bus *bus) {
+        if (!bus)
+                return NULL;
+
+        sd_bus_close(bus);
+
+        return sd_bus_unref(bus);
+}
+
 _public_ sd_bus* sd_bus_flush_close_unref(sd_bus *bus) {
         if (!bus)
                 return NULL;
 
         /* Have to do this before flush() to prevent hang */
         bus_kill_exec(bus);
-
         sd_bus_flush(bus);
-        sd_bus_close(bus);
 
-        return sd_bus_unref(bus);
+        return sd_bus_close_unref(bus);
 }
 
 void bus_enter_closing(sd_bus *bus) {

src/systemd/sd-bus.h

@@ -170,6 +170,7 @@ void sd_bus_close(sd_bus *bus);
 
 sd_bus *sd_bus_ref(sd_bus *bus);
 sd_bus *sd_bus_unref(sd_bus *bus);
+sd_bus *sd_bus_close_unref(sd_bus *bus);
 sd_bus *sd_bus_flush_close_unref(sd_bus *bus);
 
 void sd_bus_default_flush_close(void);
@@ -493,6 +494,7 @@ int sd_bus_track_get_destroy_callback(sd_bus_track *s, sd_bus_destroy_t *ret);
 
 /* Define helpers so that __attribute__((cleanup(sd_bus_unrefp))) and similar may be used. */
 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus, sd_bus_unref);
+_SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus, sd_bus_close_unref);
 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus, sd_bus_flush_close_unref);
 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus_slot, sd_bus_slot_unref);
 _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus_message, sd_bus_message_unref);