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, 10 insertions, 10 deletions

diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c
index 2562396180..5457b2451b 100644
--- a/src/core/dbus-manager.c
+++ b/src/core/dbus-manager.c
@@ -384,7 +384,7 @@ static int method_get_unit(sd_bus_message *message, void *userdata, sd_bus_error
                 return r;
 
         if (isempty(name)) {
-                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+                _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
                 pid_t pid;
 
                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_PID, &creds);
@@ -436,7 +436,7 @@ static int method_get_unit_by_pid(sd_bus_message *message, void *userdata, sd_bu
                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid PID " PID_FMT, pid);
 
         if (pid == 0) {
-                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+                _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
 
                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_PID, &creds);
                 if (r < 0)
@@ -479,7 +479,7 @@ static int method_load_unit(sd_bus_message *message, void *userdata, sd_bus_erro
                 return r;
 
         if (isempty(name)) {
-                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+                _cleanup_(sd_bus_creds_unrefp) sd_bus_creds *creds = NULL;
                 pid_t pid;
 
                 r = sd_bus_query_sender_creds(message, SD_BUS_CREDS_PID, &creds);
@@ -865,7 +865,7 @@ static int method_reset_failed(sd_bus_message *message, void *userdata, sd_bus_e
 }
 
 static int list_units_filtered(sd_bus_message *message, void *userdata, sd_bus_error *error, char **states) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         Manager *m = userdata;
         const char *k;
         Iterator i;
@@ -953,7 +953,7 @@ static int method_list_units_filtered(sd_bus_message *message, void *userdata, s
 }
 
 static int method_list_jobs(sd_bus_message *message, void *userdata, sd_bus_error *error) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         Manager *m = userdata;
         Iterator i;
         Job *j;
@@ -1441,7 +1441,7 @@ static int method_set_exit_code(sd_bus_message *message, void *userdata, sd_bus_
 }
 
 static int method_list_unit_files(sd_bus_message *message, void *userdata, sd_bus_error *error) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         Manager *m = userdata;
         UnitFileList *item;
         Hashmap *h;
@@ -1547,7 +1547,7 @@ static int method_get_default_target(sd_bus_message *message, void *userdata, sd
 }
 
 static int send_unit_files_changed(sd_bus *bus, void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *message = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *message = NULL;
         int r;
 
         assert(bus);
@@ -1566,7 +1566,7 @@ static int reply_unit_file_changes_and_free(
                 UnitFileChange *changes,
                 unsigned n_changes) {
 
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         unsigned i;
         int r;
 
@@ -2023,7 +2023,7 @@ const sd_bus_vtable bus_manager_vtable[] = {
 };
 
 static int send_finished(sd_bus *bus, void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *message = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *message = NULL;
         usec_t *times = userdata;
         int r;
 
@@ -2071,7 +2071,7 @@ void bus_manager_send_finished(
 }
 
 static int send_reloading(sd_bus *bus, void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *message = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *message = NULL;
         int r;
 
         assert(bus);