Queueing Classes

Modules
	Class Modules
	Class Object

Addition/Modification
struct nl_msg *	rtnl_class_build_add_request (struct rtnl_class *class, int flags)
	Build a netlink message to add a new class.
int	rtnl_class_add (struct nl_handle *handle, struct rtnl_class *class, int flags)
	Add a new class.

Cache Management
struct nl_cache *	rtnl_class_alloc_cache (struct nl_handle *handle, int ifindex)
	Build a class cache including all classes attached to the specified interface.

Detailed Description

Function Documentation

rtnl_class_build_add_request()

struct nl_msg * rtnl_class_build_add_request	(	struct rtnl_class *	class,
		int	flags
	)

Parameters

class	class to add
flags	additional netlink message flags

Builds a new netlink message requesting an addition of a class. The netlink message header isn't fully equipped with all relevant fields and must be sent out via nl_send_auto_complete() or supplemented as needed.

Common message flags

• NLM_F_REPLACE - replace possibly existing classes

Returns

New netlink message

Definition at line 128 of file class.c.

{
        return class_build(class, RTM_NEWTCLASS, NLM_F_CREATE | flags);
}

References NLM_F_CREATE.

Referenced by rtnl_class_add().

rtnl_class_add()

int rtnl_class_add	(	struct nl_handle *	handle,
		struct rtnl_class *	class,
		int	flags
	)

Parameters

handle	netlink handle
class	class to delete
flags	additional netlink message flags

Builds a netlink message by calling rtnl_qdisc_build_add_request(), sends the request to the kernel and waits for the next ACK to be received and thus blocks until the request has been processed.

Common message flags

• NLM_F_REPLACE - replace possibly existing classes

Returns

0 on success or a negative error code

Definition at line 148 of file class.c.

{
        struct nl_msg *msg;
        int err;
 
        msg = rtnl_class_build_add_request(class, flags);
        if (!msg)
                return nl_errno(ENOMEM);
 
        err = nl_send_auto_complete(handle, msg);
        nlmsg_free(msg);
        if (err < 0)
                return err;
 
        return nl_wait_for_ack(handle);
}

References nl_send_auto_complete(), nl_wait_for_ack(), nlmsg_free(), and rtnl_class_build_add_request().

rtnl_class_alloc_cache()

struct nl_cache * rtnl_class_alloc_cache	(	struct nl_handle *	handle,
		int	ifindex
	)

Parameters

handle	netlink handle
ifindex	interface index of the link the classes are attached to.

Allocates a new cache, initializes it properly and updates it to include all classes attached to the specified interface.

Returns

The cache or NULL if an error has occured.

Definition at line 184 of file class.c.

{
        struct nl_cache * cache;
        
        cache = nl_cache_alloc(&rtnl_class_ops);
        if (!cache)
                return NULL;
 
        cache->c_iarg1 = ifindex;
        
        if (handle && nl_cache_refill(handle, cache) < 0) {
                nl_cache_free(cache);
                return NULL;
        }
 
        return cache;
}

References nl_cache_alloc(), nl_cache_free(), and nl_cache_refill().