sd-bus: introduce new sd_bus_flush_close_unref() call

sd_bus_flush_close_unref() is a call that simply combines sd_bus_flush()
(which writes all unwritten messages out) + sd_bus_close() (which
terminates the connection, releasing all unread messages) +
sd_bus_unref() (which frees the connection).

The combination of this call is used pretty frequently in systemd tools
right before exiting, and should also be relevant for most external
clients, and is hence useful to cover in a call of its own.

Previously the combination of the three calls was already done in the
_cleanup_bus_close_unref_ macro, but this was only available internally.

Also see #327

6 files changed, 17 insertions, 5 deletions

diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym
index 97005dbac3..7bf1d66dde 100644
--- a/src/libsystemd/libsystemd.sym
+++ b/src/libsystemd/libsystemd.sym
@@ -465,4 +465,5 @@ global:
         /* sd-bus */
         sd_bus_emit_object_added;
         sd_bus_emit_object_removed;
+        sd_bus_flush_close_unref;
 } LIBSYSTEMD_221;
diff --git a/src/libsystemd/sd-bus/busctl.c b/src/libsystemd/sd-bus/busctl.c
index 39caa4e7d6..704939c6cf 100644
--- a/src/libsystemd/sd-bus/busctl.c
+++ b/src/libsystemd/sd-bus/busctl.c
@@ -1973,7 +1973,7 @@ static int busctl_main(sd_bus *bus, int argc, char *argv[]) {
 }
 
 int main(int argc, char *argv[]) {
-        _cleanup_bus_close_unref_ sd_bus *bus = NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
         int r;
 
         log_parse_environment();
diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c
index 5dd6468707..0ca225c617 100644
--- a/src/libsystemd/sd-bus/sd-bus.c
+++ b/src/libsystemd/sd-bus/sd-bus.c
@@ -1428,6 +1428,17 @@ _public_ void sd_bus_close(sd_bus *bus) {
          * ioctl on the fd when they are freed. */
 }
 
+_public_ sd_bus* sd_bus_flush_close_unref(sd_bus *bus) {
+
+        if (!bus)
+                return NULL;
+
+        sd_bus_flush(bus);
+        sd_bus_close(bus);
+
+        return sd_bus_unref(bus);
+}
+
 static void bus_enter_closing(sd_bus *bus) {
         assert(bus);
 
diff --git a/src/libsystemd/sd-bus/test-bus-chat.c b/src/libsystemd/sd-bus/test-bus-chat.c
index 046e999008..754335b5e7 100644
--- a/src/libsystemd/sd-bus/test-bus-chat.c
+++ b/src/libsystemd/sd-bus/test-bus-chat.c
@@ -262,7 +262,7 @@ fail:
 
 static void* client1(void*p) {
         _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        _cleanup_bus_close_unref_ sd_bus *bus = NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
         const char *hello;
         int r;
@@ -361,7 +361,7 @@ static int quit_callback(sd_bus_message *m, void *userdata, sd_bus_error *ret_er
 
 static void* client2(void*p) {
         _cleanup_bus_message_unref_ sd_bus_message *m = NULL, *reply = NULL;
-        _cleanup_bus_close_unref_ sd_bus *bus = NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
         bool quit = false;
         const char *mid;
diff --git a/src/libsystemd/sd-bus/test-bus-gvariant.c b/src/libsystemd/sd-bus/test-bus-gvariant.c
index 22ea00c2fb..9b7dd2e499 100644
--- a/src/libsystemd/sd-bus/test-bus-gvariant.c
+++ b/src/libsystemd/sd-bus/test-bus-gvariant.c
@@ -132,7 +132,7 @@ static void test_bus_gvariant_get_alignment(void) {
 
 static void test_marshal(void) {
         _cleanup_bus_message_unref_ sd_bus_message *m = NULL, *n = NULL;
-        _cleanup_bus_close_unref_ sd_bus *bus = NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
         _cleanup_free_ void *blob;
         size_t sz;
         int r;
diff --git a/src/libsystemd/sd-bus/test-bus-match.c b/src/libsystemd/sd-bus/test-bus-match.c
index a1687b1c7b..83cb5c62c2 100644
--- a/src/libsystemd/sd-bus/test-bus-match.c
+++ b/src/libsystemd/sd-bus/test-bus-match.c
@@ -92,7 +92,7 @@ int main(int argc, char *argv[]) {
         };
 
         _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
-        _cleanup_bus_close_unref_ sd_bus *bus = NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
         enum bus_match_node_type i;
         sd_bus_slot slots[19];
         int r;