cgroups: simplify

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

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index 21abd910dd8690109f484a7cef138f2ddaf7e040..440a19efad10a7314928e37cd378c03740ce4890 100644 (file)
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -895,13 +895,15 @@ static int get_existing_subsystems(char ***klist, char ***nlist)
        return 0;
 }
 
-static void trim(char *s)
+static char *trim(char *s)
 {
        size_t len;
 
        len = strlen(s);
        while ((len > 1) && (s[len - 1] == '\n'))
                s[--len] = '\0';
+
+       return s;
 }
 
 static void lxc_cgfsng_print_hierarchies(struct cgroup_ops *ops)
@@ -1683,8 +1685,8 @@ __cgfsng_ops static bool cgfsng_mount(struct cgroup_ops *ops,
                                      const char *root, int type)
 {
        __do_free char *cgroup_root = NULL;
+       bool has_cgns = false, wants_force_mount = false;
        int ret;
-       bool has_cgns = false, retval = false, wants_force_mount = false;
 
        if (!ops)
                return ret_set_errno(false, ENOENT);
@@ -1722,12 +1724,12 @@ __cgfsng_ops static bool cgfsng_mount(struct cgroup_ops *ops,
        cgroup_root = must_make_path(root, DEFAULT_CGROUP_MOUNTPOINT, NULL);
        if (ops->cgroup_layout == CGROUP_LAYOUT_UNIFIED) {
                if (has_cgns && wants_force_mount) {
-                       /* If cgroup namespaces are supported but the container
+                       /*
+                        * If cgroup namespaces are supported but the container
                         * will not have CAP_SYS_ADMIN after it has started we
                         * need to mount the cgroups manually.
                         */
-                       return cg_mount_in_cgroup_namespace(type, ops->unified,
-                                                           cgroup_root) == 0;
+                       return cg_mount_in_cgroup_namespace(type, ops->unified, cgroup_root) == 0;
                }
 
                return cg_mount_cgroup_full(type, ops->unified, cgroup_root) == 0;
@@ -1738,7 +1740,7 @@ __cgfsng_ops static bool cgfsng_mount(struct cgroup_ops *ops,
                         MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_RELATIME,
                         "size=10240k,mode=755", root);
        if (ret < 0)
-               goto on_error;
+               return false;
 
        for (int i = 0; ops->hierarchies[i]; i++) {
                __do_free char *controllerpath = NULL, *path2 = NULL;
@@ -1754,10 +1756,8 @@ __cgfsng_ops static bool cgfsng_mount(struct cgroup_ops *ops,
                        continue;
 
                ret = mkdir(controllerpath, 0755);
-               if (ret < 0) {
-                       ERROR("Error creating cgroup path: %s", controllerpath);
-                       goto on_error;
-               }
+               if (ret < 0)
+                       return log_error_errno(false, errno, "Error creating cgroup path: %s", controllerpath);
 
                if (has_cgns && wants_force_mount) {
                        /* If cgroup namespaces are supported but the container
@@ -1766,14 +1766,14 @@ __cgfsng_ops static bool cgfsng_mount(struct cgroup_ops *ops,
                         */
                        ret = cg_mount_in_cgroup_namespace(type, h, controllerpath);
                        if (ret < 0)
-                               goto on_error;
+                               return false;
 
                        continue;
                }
 
                ret = cg_mount_cgroup_full(type, h, controllerpath);
                if (ret < 0)
-                       goto on_error;
+                       return false;
 
                if (!cg_mount_needs_subdirs(type))
                        continue;
@@ -1782,17 +1782,15 @@ __cgfsng_ops static bool cgfsng_mount(struct cgroup_ops *ops,
                                       ops->container_cgroup, NULL);
                ret = mkdir_p(path2, 0755);
                if (ret < 0)
-                       goto on_error;
+                       return false;
 
                ret = cg_legacy_mount_controllers(type, h, controllerpath,
                                                  path2, ops->container_cgroup);
                if (ret < 0)
-                       goto on_error;
+                       return false;
        }
-       retval = true;
 
-on_error:
-       return retval;
+       return true;
 }
 
 /* Only root needs to escape to the cgroup of its init. */
@@ -3001,8 +2999,8 @@ static int cg_hybrid_init(struct cgroup_ops *ops, bool relative, bool unprivileg
 static char *cg_unified_get_current_cgroup(bool relative)
 {
        __do_free char *basecginfo = NULL;
+       char *copy;
        char *base_cgroup;
-       char *copy = NULL;
 
        if (!relative && (geteuid() == 0))
                basecginfo = read_file("/proc/1/cgroup");
@@ -3013,18 +3011,14 @@ static char *cg_unified_get_current_cgroup(bool relative)
 
        base_cgroup = strstr(basecginfo, "0::/");
        if (!base_cgroup)
-               goto cleanup_on_err;
+               return NULL;
 
        base_cgroup = base_cgroup + 3;
        copy = copy_to_eol(base_cgroup);
        if (!copy)
-               goto cleanup_on_err;
-
-cleanup_on_err:
-       if (copy)
-               trim(copy);
+               return NULL;
 
-       return copy;
+       return trim(copy);
 }
 
 static int cg_unified_init(struct cgroup_ops *ops, bool relative,