Move common code to lxc_cgroup_create

For both the ns_cgroup and the usual cgroup creation, we have to
check if a previous does not exist and remove it if it is empty.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>

diff --git a/src/lxc/cgroup.c b/src/lxc/cgroup.c
index 4b549065f7d009980cd7d537be625e12f87dc4bf..b711c64abe867a388a629929ce27f5ce54679823 100644 (file)
--- a/src/lxc/cgroup.c
+++ b/src/lxc/cgroup.c
@@ -85,71 +85,65 @@ out:
         return err;
 }
 
-int lxc_rename_nsgroup(const char *name, pid_t pid)
+int lxc_rename_nsgroup(const char *mnt, const char *name, pid_t pid)
 {
        char oldname[MAXPATHLEN];
-       char newname[MAXPATHLEN];
-       char cgroup[MAXPATHLEN];
-       int ret;
 
-       if (get_cgroup_mount(MTAB, cgroup)) {
-               ERROR("cgroup is not mounted");
-               return -1;
-       }
+       snprintf(oldname, MAXPATHLEN, "%s/%d", mnt, pid);
 
-       snprintf(oldname, MAXPATHLEN, "%s/%d", cgroup, pid);
-       snprintf(newname, MAXPATHLEN, "%s/%s", cgroup, name);
-
-       /* there is a previous cgroup, assume it is empty, otherwise
-        * that fails */
-       if (!access(newname, F_OK)) {
-               ret = rmdir(newname);
-               if (ret) {
-                       SYSERROR("failed to remove previous cgroup '%s'",
-                                newname);
-                       return ret;
-               }
+       if (rename(oldname, name)) {
+               SYSERROR("failed to rename cgroup %s->%s", oldname, name);
+               return -1;
        }
 
-       ret = rename(oldname, newname);
-       if (ret)
-               SYSERROR("failed to rename cgroup %s->%s", oldname, newname);
-       else
-               DEBUG("'%s' renamed to '%s'", oldname, newname);
-
+       DEBUG("'%s' renamed to '%s'", oldname, name);
 
-       return ret;
+       return 0;
 }
 
-int lxc_unlink_nsgroup(const char *name)
+int lxc_cgroup_create(const char *name, pid_t pid)
 {
-       char nsgroup[MAXPATHLEN];
-       char cgroup[MAXPATHLEN];
-       int ret;
+       char cgmnt[MAXPATHLEN];
+       char cgname[MAXPATHLEN];
 
-       if (get_cgroup_mount(MTAB, cgroup)) {
+       if (get_cgroup_mount(MTAB, cgmnt)) {
                ERROR("cgroup is not mounted");
                return -1;
        }
 
-       snprintf(nsgroup, MAXPATHLEN, "%s/%s", cgroup, name);
-       ret = rmdir(nsgroup);
-       if (ret)
-               SYSERROR("failed to remove cgroup '%s'", nsgroup);
-       else
-               DEBUG("'%s' unlinked", nsgroup);
+       snprintf(cgname, MAXPATHLEN, "%s/%s", cgmnt, name);
 
-       return ret;
-}
+       /*
+        * There is a previous cgroup, assume it is empty,
+        * otherwise that fails
+        */
+       if (!access(cgname, F_OK) && rmdir(cgname)) {
+               SYSERROR("failed to remove previous cgroup '%s'", cgname);
+               return -1;
+       }
 
-int lxc_cgroup_create(const char *name, pid_t pid)
-{
-       return lxc_rename_nsgroup(name, pid);
+       return lxc_rename_nsgroup(cgmnt, cgname, pid);
 }
 
 int lxc_cgroup_destroy(const char *name)
 {
-       return lxc_unlink_nsgroup(name);
+       char cgmnt[MAXPATHLEN];
+       char cgname[MAXPATHLEN];
+
+       if (get_cgroup_mount(MTAB, cgmnt)) {
+               ERROR("cgroup is not mounted");
+               return -1;
+       }
+
+       snprintf(cgname, MAXPATHLEN, "%s/%s", cgmnt, name);
+       if (rmdir(cgmnt)) {
+               SYSERROR("failed to remove cgroup '%s'", cgname);
+               return -1;
+       }
+
+       DEBUG("'%s' unlinked", cgname);
+
+       return 0;
 }
 
 int lxc_cgroup_path_get(char **path, const char *name)