[NETLINK]: New message building macros

NLMSG_PUT_ANSWER(skb, nlcb, type, length)
   Start a new netlink message as answer to a request,
   returns the message header.

 NLMSG_END(skb, nlh)
   End a netlink message, fixes total message length,
   returns skb->len.

 NLMSG_CANCEL(skb, nlh)
   Cancel the building process and trim whole message
   from skb again, returns -1.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thomas Graf 2005-06-18 22:50:12 -07:00 committed by David S. Miller
parent e52c1f17e4
commit f88a10d656

View File

@ -171,8 +171,21 @@ __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len)
}
#define NLMSG_PUT(skb, pid, seq, type, len) \
({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) goto nlmsg_failure; \
__nlmsg_put(skb, pid, seq, type, len); })
({ if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) \
goto nlmsg_failure; \
__nlmsg_put(skb, pid, seq, type, len); })
#define NLMSG_PUT_ANSWER(skb, cb, type, len) \
NLMSG_PUT(skb, NETLINK_CB((cb)->skb).pid, \
(cb)->nlh->nlmsg_seq, type, len)
#define NLMSG_END(skb, nlh) \
({ (nlh)->nlmsg_len = (skb)->tail - (unsigned char *) (nlh); \
(skb)->len; })
#define NLMSG_CANCEL(skb, nlh) \
({ skb_trim(skb, (unsigned char *) (nlh) - (skb)->data); \
-1; })
extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
struct nlmsghdr *nlh,