tree-wide: port cgroup cleanup to call_cleaner(cgroup_exit)

src/lxc/attach.c

@@ -1176,7 +1176,7 @@ int lxc_attach(struct lxc_container *container, lxc_attach_exec_t exec_function,
 			 */
 			ret = cgroup_attach(name, lxcpath, pid);
 			if (ret) {
-				__do_cgroup_exit struct cgroup_ops *cgroup_ops = NULL;
+				call_cleaner(cgroup_exit) struct cgroup_ops *cgroup_ops = NULL;
 
 				cgroup_ops = cgroup_init(conf);
 				if (!cgroup_ops)

src/lxc/cgroups/cgroup.h

@@ -8,6 +8,7 @@
 #include <sys/types.h>
 
 #include "macro.h"
+#include "memory_utils.h"
 
 #define DEFAULT_CGROUP_MOUNTPOINT "/sys/fs/cgroup"
 #define DEFAULT_PAYLOAD_CGROUP_PREFIX "lxc.payload."
@@ -171,20 +172,14 @@ struct cgroup_ops {
 };
 
 extern struct cgroup_ops *cgroup_init(struct lxc_conf *conf);
+
 extern void cgroup_exit(struct cgroup_ops *ops);
+define_cleanup_function(struct cgroup_ops *, cgroup_exit);
 
 extern void prune_init_scope(char *cg);
 
-static inline void __auto_cgroup_exit__(struct cgroup_ops **ops)
-{
-	if (*ops)
-		cgroup_exit(*ops);
-}
-
 extern int cgroup_attach(const char *name, const char *lxcpath, int64_t pid);
 
-#define __do_cgroup_exit __attribute__((__cleanup__(__auto_cgroup_exit__)))
-
 static inline bool pure_unified_layout(const struct cgroup_ops *ops)
 {
 	return ops->cgroup_layout == CGROUP_LAYOUT_UNIFIED;

src/lxc/freezer.c

@@ -35,7 +35,7 @@ static void notify_state_listeners(const char *name, const char *lxcpath,
 static int do_freeze_thaw(bool freeze, struct lxc_conf *conf, const char *name,
 			  const char *lxcpath)
 {
-	__do_cgroup_exit struct cgroup_ops *cgroup_ops = NULL;
+	call_cleaner(cgroup_exit) struct cgroup_ops *cgroup_ops = NULL;
 	lxc_state_t new_state = freeze ? FROZEN : THAWED;
 	int ret;
 	const char *state;

src/lxc/lxccontainer.c

@@ -3308,8 +3308,7 @@ WRAP_API_1(bool, lxcapi_set_config_path, const char *)
 
 static bool do_lxcapi_set_cgroup_item(struct lxc_container *c, const char *subsys, const char *value)
 {
-	int ret;
-	struct cgroup_ops *cgroup_ops;
+	call_cleaner(cgroup_exit) struct cgroup_ops *cgroup_ops = NULL;
 
 	if (!c)
 		return false;
@@ -3321,19 +3320,15 @@ static bool do_lxcapi_set_cgroup_item(struct lxc_container *c, const char *subsy
 	if (!cgroup_ops)
 		return false;
 
-	ret = cgroup_ops->set(cgroup_ops, subsys, value, c->name, c->config_path);
-
-	cgroup_exit(cgroup_ops);
-
-	return ret == 0;
+	return cgroup_ops->set(cgroup_ops, subsys, value, c->name,
+			       c->config_path) == 0;
 }
 
 WRAP_API_2(bool, lxcapi_set_cgroup_item, const char *, const char *)
 
 static int do_lxcapi_get_cgroup_item(struct lxc_container *c, const char *subsys, char *retv, int inlen)
 {
-	int ret;
-	struct cgroup_ops *cgroup_ops;
+	call_cleaner(cgroup_exit) struct cgroup_ops *cgroup_ops = NULL;
 
 	if (!c)
 		return -1;
@@ -3345,12 +3340,8 @@ static int do_lxcapi_get_cgroup_item(struct lxc_container *c, const char *subsys
 	if (!cgroup_ops)
 		return -1;
 
-	ret = cgroup_ops->get(cgroup_ops, subsys, retv, inlen, c->name,
-			      c->config_path);
-
-	cgroup_exit(cgroup_ops);
-
-	return ret;
+	return cgroup_ops->get(cgroup_ops, subsys, retv, inlen, c->name,
+			       c->config_path);
 }
 
 WRAP_API_3(int, lxcapi_get_cgroup_item, const char *, char *, int)