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, 48 insertions, 49 deletions

diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index 7e17c7a41c..0a01bd3e20 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -40,7 +40,6 @@
 #include "cgroup-util.h"
 #include "copy.h"
 #include "env-util.h"
-#include "event-util.h"
 #include "fd-util.h"
 #include "hostname-util.h"
 #include "import-util.h"
@@ -129,8 +128,8 @@ static int compare_machine_info(const void *a, const void *b) {
 static int list_machines(int argc, char *argv[], void *userdata) {
 
         size_t max_name = strlen("MACHINE"), max_class = strlen("CLASS"), max_service = strlen("SERVICE");
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         _cleanup_free_ MachineInfo *machines = NULL;
         const char *name, *class, *service, *object;
         size_t n_machines = 0, n_allocated = 0, j;
@@ -230,9 +229,9 @@ static int compare_image_info(const void *a, const void *b) {
 
 static int list_images(int argc, char *argv[], void *userdata) {
 
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         size_t max_name = strlen("NAME"), max_type = strlen("TYPE"), max_size = strlen("USAGE"), max_crtime = strlen("CREATED"), max_mtime = strlen("MODIFIED");
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         _cleanup_free_ ImageInfo *images = NULL;
         size_t n_images = 0, n_allocated = 0, j;
         const char *name, *type, *object;
@@ -344,8 +343,8 @@ static int list_images(int argc, char *argv[], void *userdata) {
 }
 
 static int show_unit_cgroup(sd_bus *bus, const char *unit, pid_t leader) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_free_ char *path = NULL;
         const char *cgroup;
         int r;
@@ -393,7 +392,7 @@ static int show_unit_cgroup(sd_bus *bus, const char *unit, pid_t leader) {
 }
 
 static int print_addresses(sd_bus *bus, const char *name, int ifi, const char *prefix, const char *prefix2) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         int r;
 
         assert(bus);
@@ -454,7 +453,7 @@ static int print_addresses(sd_bus *bus, const char *name, int ifi, const char *p
 }
 
 static int print_os_release(sd_bus *bus, const char *name, const char *prefix) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         const char *k, *v, *pretty = NULL;
         int r;
 
@@ -701,8 +700,8 @@ static int show_machine_properties(sd_bus *bus, const char *path, bool *new_line
 
 static int show_machine(int argc, char *argv[], void *userdata) {
 
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         bool properties, new_line = false;
         sd_bus *bus = userdata;
         int r = 0, i;
@@ -950,8 +949,8 @@ static int show_image_properties(sd_bus *bus, const char *path, bool *new_line)
 
 static int show_image(int argc, char *argv[], void *userdata) {
 
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         bool properties, new_line = false;
         sd_bus *bus = userdata;
         int r = 0, i;
@@ -1006,7 +1005,7 @@ static int show_image(int argc, char *argv[], void *userdata) {
 }
 
 static int kill_machine(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r, i;
 
@@ -1051,7 +1050,7 @@ static int poweroff_machine(int argc, char *argv[], void *userdata) {
 }
 
 static int terminate_machine(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r, i;
 
@@ -1079,7 +1078,7 @@ static int terminate_machine(int argc, char *argv[], void *userdata) {
 }
 
 static int copy_files(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_free_ char *abs_host_path = NULL;
         char *dest, *host_path, *container_path;
         sd_bus *bus = userdata;
@@ -1122,7 +1121,7 @@ static int copy_files(int argc, char *argv[], void *userdata) {
 }
 
 static int bind_mount(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r;
 
@@ -1226,11 +1225,11 @@ static int process_forward(sd_event *event, PTYForward **forward, int master, PT
 }
 
 static int login_machine(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
-        _cleanup_bus_slot_unref_ sd_bus_slot *slot = NULL;
-        _cleanup_event_unref_ sd_event *event = NULL;
+        _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *slot = NULL;
+        _cleanup_(sd_event_unrefp) sd_event *event = NULL;
         int master = -1, r;
         sd_bus *bus = userdata;
         const char *pty, *match, *machine;
@@ -1293,11 +1292,11 @@ static int login_machine(int argc, char *argv[], void *userdata) {
 }
 
 static int shell_machine(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL, *m = NULL;
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL, *m = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
-        _cleanup_bus_slot_unref_ sd_bus_slot *slot = NULL;
-        _cleanup_event_unref_ sd_event *event = NULL;
+        _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *slot = NULL;
+        _cleanup_(sd_event_unrefp) sd_event *event = NULL;
         int master = -1, r;
         sd_bus *bus = userdata;
         const char *pty, *match, *machine, *path, *uid = NULL;
@@ -1397,7 +1396,7 @@ static int shell_machine(int argc, char *argv[], void *userdata) {
 }
 
 static int remove_image(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r, i;
 
@@ -1425,7 +1424,7 @@ static int remove_image(int argc, char *argv[], void *userdata) {
 }
 
 static int rename_image(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r;
 
@@ -1449,7 +1448,7 @@ static int rename_image(int argc, char *argv[], void *userdata) {
 }
 
 static int clone_image(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r;
 
@@ -1473,7 +1472,7 @@ static int clone_image(int argc, char *argv[], void *userdata) {
 }
 
 static int read_only_image(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int b = true, r;
 
@@ -1528,7 +1527,7 @@ static int make_service_name(const char *name, char **ret) {
 }
 
 static int start_machine(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_(bus_wait_for_jobs_freep) BusWaitForJobs *w = NULL;
         sd_bus *bus = userdata;
         int r, i;
@@ -1542,7 +1541,7 @@ static int start_machine(int argc, char *argv[], void *userdata) {
                 return log_oom();
 
         for (i = 1; i < argc; i++) {
-                _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+                _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
                 _cleanup_free_ char *unit = NULL;
                 const char *object;
 
@@ -1581,8 +1580,8 @@ static int start_machine(int argc, char *argv[], void *userdata) {
 }
 
 static int enable_machine(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL, *reply = NULL;
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         int carries_install_info = 0;
         const char *method = NULL;
         sd_bus *bus = userdata;
@@ -1721,10 +1720,10 @@ static int transfer_signal_handler(sd_event_source *s, const struct signalfd_sig
 }
 
 static int transfer_image_common(sd_bus *bus, sd_bus_message *m) {
-        _cleanup_bus_slot_unref_ sd_bus_slot *slot_job_removed = NULL, *slot_log_message = NULL;
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        _cleanup_event_unref_ sd_event* event = NULL;
+        _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *slot_job_removed = NULL, *slot_log_message = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(sd_event_unrefp) sd_event* event = NULL;
         const char *path = NULL;
         uint32_t id;
         int r;
@@ -1791,7 +1790,7 @@ static int transfer_image_common(sd_bus *bus, sd_bus_message *m) {
 }
 
 static int import_tar(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_free_ char *ll = NULL;
         _cleanup_close_ int fd = -1;
         const char *local = NULL, *path = NULL;
@@ -1858,7 +1857,7 @@ static int import_tar(int argc, char *argv[], void *userdata) {
 }
 
 static int import_raw(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_free_ char *ll = NULL;
         _cleanup_close_ int fd = -1;
         const char *local = NULL, *path = NULL;
@@ -1940,7 +1939,7 @@ static void determine_compression_from_filename(const char *p) {
 }
 
 static int export_tar(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_close_ int fd = -1;
         const char *local = NULL, *path = NULL;
         sd_bus *bus = userdata;
@@ -1990,7 +1989,7 @@ static int export_tar(int argc, char *argv[], void *userdata) {
 }
 
 static int export_raw(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_close_ int fd = -1;
         const char *local = NULL, *path = NULL;
         sd_bus *bus = userdata;
@@ -2040,7 +2039,7 @@ static int export_raw(int argc, char *argv[], void *userdata) {
 }
 
 static int pull_tar(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_free_ char *l = NULL, *ll = NULL;
         const char *local, *remote;
         sd_bus *bus = userdata;
@@ -2104,7 +2103,7 @@ static int pull_tar(int argc, char *argv[], void *userdata) {
 }
 
 static int pull_raw(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         _cleanup_free_ char *l = NULL, *ll = NULL;
         const char *local, *remote;
         sd_bus *bus = userdata;
@@ -2168,7 +2167,7 @@ static int pull_raw(int argc, char *argv[], void *userdata) {
 }
 
 static int pull_dkr(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
         const char *local, *remote, *tag;
         sd_bus *bus = userdata;
         int r;
@@ -2255,8 +2254,8 @@ static int compare_transfer_info(const void *a, const void *b) {
 
 static int list_transfers(int argc, char *argv[], void *userdata) {
         size_t max_type = strlen("TYPE"), max_local = strlen("LOCAL"), max_remote = strlen("REMOTE");
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_free_ TransferInfo *transfers = NULL;
         size_t n_transfers = 0, n_allocated = 0, j;
         const char *type, *remote, *local, *object;
@@ -2346,7 +2345,7 @@ static int list_transfers(int argc, char *argv[], void *userdata) {
 }
 
 static int cancel_transfer(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         int r, i;
 
@@ -2380,7 +2379,7 @@ static int cancel_transfer(int argc, char *argv[], void *userdata) {
 }
 
 static int set_limit(int argc, char *argv[], void *userdata) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         sd_bus *bus = userdata;
         uint64_t limit;
         int r;
@@ -2737,7 +2736,7 @@ static int machinectl_main(int argc, char *argv[], sd_bus *bus) {
 }
 
 int main(int argc, char*argv[]) {
-        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
+        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
         int r;
 
         setlocale(LC_ALL, "");