cgroups/cgfsng: rework cgfsng_payload_create()

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index cdb1e7eb2d6756e1837b9f04fac6735b51051d71..d1a18174cfe649aabbf027f4990cf3a31554e822 100644 (file)
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -1366,32 +1366,36 @@ __cgfsng_ops static inline bool cgfsng_monitor_create(struct cgroup_ops *ops,
  * next cgroup_pattern-1, -2, ..., -999.
  */
 __cgfsng_ops static inline bool cgfsng_payload_create(struct cgroup_ops *ops,
-                                                       struct lxc_handler *handler)
+                                                     struct lxc_handler *handler)
 {
        __do_free char *container_cgroup = NULL, *tmp = NULL;
+       int idx = 0;
        int i, ret;
        size_t len;
        char *offset;
-       int idx = 0;
-       struct lxc_conf *conf = handler->conf;
-
-       if (ops->container_cgroup)
-               return false;
+       struct lxc_conf *conf;
 
-       if (!conf)
-               return false;
+       if (!ops)
+               return ret_set_errno(false, ENOENT);
 
        if (!ops->hierarchies)
                return true;
 
+       if (ops->container_cgroup)
+               return ret_set_errno(false, EEXIST);
+
+       if (!handler || !handler->conf)
+               return ret_set_errno(false, EINVAL);
+
+       conf = handler->conf;
+
        if (conf->cgroup_meta.dir)
                tmp = lxc_string_join("/", (const char *[]){conf->cgroup_meta.dir, handler->name, NULL}, false);
        else
                tmp = lxc_string_replace("%n", handler->name, ops->cgroup_pattern);
-       if (!tmp) {
-               ERROR("Failed expanding cgroup name pattern");
-               return false;
-       }
+       if (!tmp)
+               return log_error_errno(false, ENOMEM,
+                                      "Failed expanding cgroup name pattern");
 
        len = strlen(tmp) + 5; /* leave room for -NNN\0 */
        container_cgroup = must_realloc(NULL, len);
@@ -1399,11 +1403,8 @@ __cgfsng_ops static inline bool cgfsng_payload_create(struct cgroup_ops *ops,
        offset = container_cgroup + len - 5;
 
        do {
-               if (idx) {
-                       ret = snprintf(offset, 5, "-%d", idx);
-                       if (ret < 0 || (size_t)ret >= 5)
-                               return false;
-               }
+               if (idx)
+                       sprintf(offset, "-%d", idx);
 
                for (i = 0; ops->hierarchies[i]; i++) {
                        if (!container_create_path_for_hierarchy(ops->hierarchies[i],
@@ -1421,7 +1422,7 @@ __cgfsng_ops static inline bool cgfsng_payload_create(struct cgroup_ops *ops,
        } while (ops->hierarchies[i] && idx > 0 && idx < 1000);
 
        if (idx == 1000)
-               return false;
+               return ret_set_errno(false, ERANGE);
 
        INFO("The container process uses \"%s\" as cgroup", container_cgroup);
        ops->container_cgroup = move_ptr(container_cgroup);