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, 11 insertions, 11 deletions

diff --git a/src/network/networkctl.c b/src/network/networkctl.c
index 6fcb3050c7..0234825adb 100644
--- a/src/network/networkctl.c
+++ b/src/network/networkctl.c
@@ -196,8 +196,8 @@ static void setup_state_to_color(const char *state, const char **on, const char
 }
 
 static int list_links(int argc, char *argv[], void *userdata) {
-        _cleanup_netlink_message_unref_ sd_netlink_message *req = NULL, *reply = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
+        _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
         _cleanup_free_ LinkInfo *links = NULL;
         int r, c, i;
 
@@ -228,7 +228,7 @@ static int list_links(int argc, char *argv[], void *userdata) {
 
         for (i = 0; i < c; i++) {
                 _cleanup_free_ char *setup_state = NULL, *operational_state = NULL;
-                _cleanup_device_unref_ sd_device *d = NULL;
+                _cleanup_(sd_device_unrefp) sd_device *d = NULL;
                 const char *on_color_operational, *off_color_operational,
                            *on_color_setup, *off_color_setup;
                 char devid[2 + DECIMAL_STR_MAX(int)];
@@ -297,7 +297,7 @@ static int get_gateway_description(
                 int family,
                 union in_addr_union *gateway,
                 char **gateway_description) {
-        _cleanup_netlink_message_unref_ sd_netlink_message *req = NULL, *reply = NULL;
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
         sd_netlink_message *m;
         int r;
 
@@ -502,8 +502,8 @@ static int link_status_one(
                 const char *name) {
         _cleanup_strv_free_ char **dns = NULL, **ntp = NULL, **domains = NULL;
         _cleanup_free_ char *setup_state = NULL, *operational_state = NULL, *tz = NULL;
-        _cleanup_netlink_message_unref_ sd_netlink_message *req = NULL, *reply = NULL;
-        _cleanup_device_unref_ sd_device *d = NULL;
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
+        _cleanup_(sd_device_unrefp) sd_device *d = NULL;
         char devid[2 + DECIMAL_STR_MAX(int)];
         _cleanup_free_ char *t = NULL, *network = NULL;
         const char *driver = NULL, *path = NULL, *vendor = NULL, *model = NULL, *link = NULL;
@@ -674,8 +674,8 @@ static int link_status_one(
 }
 
 static int link_status(int argc, char *argv[], void *userdata) {
-        _cleanup_hwdb_unref_ sd_hwdb *hwdb = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        _cleanup_(sd_hwdb_unrefp) sd_hwdb *hwdb = NULL;
+        _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
         char **name;
         int r;
 
@@ -720,7 +720,7 @@ static int link_status(int argc, char *argv[], void *userdata) {
         pager_open_if_enabled();
 
         if (arg_all) {
-                _cleanup_netlink_message_unref_ sd_netlink_message *req = NULL, *reply = NULL;
+                _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
                 _cleanup_free_ LinkInfo *links = NULL;
                 int c, i;
 
@@ -906,8 +906,8 @@ static char *lldp_system_caps(uint16_t cap) {
 }
 
 static int link_lldp_status(int argc, char *argv[], void *userdata) {
-        _cleanup_netlink_message_unref_ sd_netlink_message *req = NULL, *reply = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
+        _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
         _cleanup_free_ LinkInfo *links = NULL;
         double ttl = -1;
         uint32_t capability;