tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easy

GLIB has recently started to officially support the gcc cleanup
attribute in its public API, hence let's do the same for our APIs.

With this patch we'll define an xyz_unrefp() call for each public
xyz_unref() call, to make it easy to use inside a
__attribute__((cleanup())) expression. Then, all code is ported over to
make use of this.

The new calls are also documented in the man pages, with examples how to
use them (well, I only added docs where the _unref() call itself already
had docs, and the examples, only cover sd_bus_unrefp() and
sd_event_unrefp()).

This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we
tend to call our destructors these days.

Note that this defines no public macro that wraps gcc's attribute and
makes it easier to use. While I think it's our duty in the library to
make our stuff easy to use, I figure it's not our duty to make gcc's own
features easy to use on its own. Most likely, client code which wants to
make use of this should define its own:

       #define _cleanup_(function) __attribute__((cleanup(function)))

Or similar, to make the gcc feature easier to use.

Making this logic public has the benefit that we can remove three header
files whose only purpose was to define these functions internally.

See #2008.

1 files changed, 5 insertions, 5 deletions

diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c
index 7810199a54..99438d87f7 100644
--- a/src/login/logind-session-dbus.c
+++ b/src/login/logind-session-dbus.c
@@ -252,7 +252,7 @@ int bus_session_method_lock(sd_bus_message *message, void *userdata, sd_bus_erro
 }
 
 static int method_set_idle_hint(sd_bus_message *message, void *userdata, sd_bus_error *error) {
-        _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+        _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
         Session *s = userdata;
         uid_t uid;
         int r, b;
@@ -327,7 +327,7 @@ int bus_session_method_kill(sd_bus_message *message, void *userdata, sd_bus_erro
 }
 
 static int method_take_control(sd_bus_message *message, void *userdata, sd_bus_error *error) {
-        _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+        _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
         Session *s = userdata;
         int r, force;
         uid_t uid;
@@ -521,7 +521,7 @@ int session_object_find(sd_bus *bus, const char *path, const char *interface, vo
         assert(m);
 
         if (streq(path, "/org/freedesktop/login1/session/self")) {
-                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+                _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
                 sd_bus_message *message;
                 const char *name;
 
@@ -598,7 +598,7 @@ int session_node_enumerator(sd_bus *bus, const char *path, void *userdata, char
 
         message = sd_bus_get_current_message(bus);
         if (message) {
-                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+                _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
                 const char *name;
 
                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_SESSION|SD_BUS_CREDS_AUGMENT, &creds);
@@ -692,7 +692,7 @@ int session_send_lock_all(Manager *m, bool lock) {
 }
 
 int session_send_create_reply(Session *s, sd_bus_error *error) {
-        _cleanup_bus_message_unref_ sd_bus_message *c = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *c = NULL;
         _cleanup_close_ int fifo_fd = -1;
         _cleanup_free_ char *p = NULL;