diff options
| -rw-r--r-- | include/libmnl/libmnl.h | 4 | ||||
| -rw-r--r-- | src/attr.c | 32 |
2 files changed, 36 insertions, 0 deletions
diff --git a/include/libmnl/libmnl.h b/include/libmnl/libmnl.h index 95167a3..d4bb7ed 100644 --- a/include/libmnl/libmnl.h +++ b/include/libmnl/libmnl.h @@ -85,6 +85,10 @@ extern void mnl_attr_put_u64(struct nlmsghdr *nlh, uint16_t type, uint64_t data) extern void mnl_attr_put_str(struct nlmsghdr *nlh, uint16_t type, const void *data); extern void mnl_attr_put_str_null(struct nlmsghdr *nlh, uint16_t type, const void *data); +/* TLV attribute nesting */ +extern struct nlattr *mnl_attr_nest_start(struct nlmsghdr *nlh, uint16_t type); +extern void mnl_attr_nest_end(struct nlmsghdr *nlh, struct nlattr *start); + /* TLV validation */ extern int mnl_attr_type_valid(const struct nlattr *attr, uint16_t maxtype); @@ -454,3 +454,35 @@ void mnl_attr_put_str_null(struct nlmsghdr *nlh, uint16_t type, const void *data { mnl_attr_put(nlh, type, strlen(data)+1, data); } + +/** + * mnl_attr_nest_start - start an attribute nest + * @nlh: pointer to the netlink message + * @type: netlink attribute type + * + * This function adds the attribute header that identifies the beginning of + * an attribute nest. This function always returns a valid pointer to the + * beginning of the nest. + */ +struct nlattr *mnl_attr_nest_start(struct nlmsghdr *nlh, uint16_t type) +{ + struct nlattr *start = mnl_nlmsg_get_payload_tail(nlh); + + /* set start->nla_len in mnl_attr_nest_end() */ + start->nla_type = NLA_F_NESTED | type; + nlh->nlmsg_len += MNL_ALIGN(sizeof(struct nlattr)); + + return start; +} + +/** + * mnl_attr_nest_end - end an attribute nest + * @nlh: pointer to the netlink message + * @start: pointer to the attribute nest returned by mnl_attr_nest_start() + * + * This function updates the attribute header that identifies the nest. + */ +void mnl_attr_nest_end(struct nlmsghdr *nlh, struct nlattr *start) +{ + start->nla_len = mnl_nlmsg_get_payload_tail(nlh) - (void *)start; +} |