/*
* TODO: this should be re-written to use the get_config_item("lxc.id_map")
* cmd api instead of getting the idmap from c->lxc_conf. The reason is
* that the id_maps may be different if the container was started with a
* -f or -s argument.
* The reason I'm punting on that is because we'll need to parse the
* idmap results.
*/
static bool cgm_attach(const char *name, const char *lxcpath, pid_t pid)
{
bool pass = false;
char *cgroup = NULL;
struct lxc_container *c;
c = lxc_container_new(name, lxcpath);
if (!c) {
ERROR("Could not load container %s:%s", lxcpath, name);
return false;
}
if (!collect_subsytems()) {
ERROR("Error collecting cgroup subsystems");
goto out;
}
// cgm_create makes sure that we have the same cgroup name for all
// subsystems, so since this is a slow command over the cmd socket,
// just get the cgroup name for the first one.
cgroup = lxc_cmd_get_cgroup_path(name, lxcpath, subsystems[0]);
if (!cgroup) {
ERROR("Failed to get cgroup for controller %s", subsystems[0]);
goto out;
}
if (!(pass = do_cgm_enter(pid, cgroup)))
ERROR("Failed to enter group %s", cgroup);
out:
free(cgroup);
lxc_container_put(c);
return pass;
}
static inline bool cgm_init(struct lxc_handler *handler)
{
if (!collect_subsytems())
return false;
if (geteuid())
return true;
// root; try to escape to root cgroup
return lxc_cgmanager_escape();
}
/*
* called during cgroup.c:cgroup_ops_init(), at startup. No threads.
* We check whether we can talk to cgmanager, escape to root cgroup if
* we are root, then close the connection.
*/
struct cgroup_ops *cgm_ops_init(void)
{
check_supports_multiple_controllers(-1);
if (!collect_subsytems())
return NULL;
if (api_version < CGM_SUPPORTS_MULT_CONTROLLERS)
cgm_supports_multiple_controllers = false;
// if root, try to escape to root cgroup
if (geteuid() == 0 && !cgm_escape()) {
free_subsystems();
return NULL;
}
return &cgmanager_ops;
}
/*
* called during cgroup.c:cgroup_ops_init(), at startup. No threads.
* We check whether we can talk to cgmanager, escape to root cgroup if
* we are root, then close the connection.
*/
struct cgroup_ops *cgm_ops_init(void)
{
if (!collect_subsytems())
return NULL;
if (!cgm_dbus_connect())
goto err1;
// root; try to escape to root cgroup
if (geteuid() == 0 && !lxc_cgmanager_escape())
goto err2;
cgm_dbus_disconnect();
return &cgmanager_ops;
err2:
cgm_dbus_disconnect();
err1:
free_subsystems();
return NULL;
}
