It will fill-in a l_genl_attr structure with the necessary information where the nested attribute starts. Thus at the end, it will update the nested attribute with the final length. --- ell/genl.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ ell/genl.h | 3 +++ 2 files changed, 51 insertions(+) diff --git a/ell/genl.c b/ell/genl.c index 2ef6a34..5484d33 100644 --- a/ell/genl.c +++ b/ell/genl.c @@ -707,6 +707,54 @@ bool l_genl_msg_append_attr(struct l_genl_msg *msg, uint16_t type, return true; } +bool l_genl_msg_append_init_recurse(struct l_genl_msg *msg, uint16_t type, + struct l_genl_attr *nested) +{ + struct nlattr *nla; + + if (!msg || !nested) + return false; + + nla = msg->data + msg->len; + nla->nla_len = NLA_HDRLEN; + nla->nla_type = type; + + if (!l_genl_msg_append_attr(msg, type, 0, NULL)) + return false; + + nested->msg = msg; + nested->data = nla; + nested->len = 0; + nested->next_data = NULL; + nested->next_len = 0; + + return true; +} + +bool l_genl_msg_append_end_recurse(struct l_genl_attr *nested) +{ + struct l_genl_msg *msg; + struct nlattr *nla; + uint32_t len; + + if (!nested || !nested->msg) + return false; + + msg = nested->msg; + len = nested->data - msg->data; + nla = msg->data + len; + + len = msg->len - len; + if (len <= NLA_HDRLEN) + return false; + + nla->nla_len = len; + + // Should we check msg alignement again? + + return true; +} + #define NLA_OK(nla,len) ((len) >= (int) sizeof(struct nlattr) && \ (nla)->nla_len >= sizeof(struct nlattr) && \ (nla)->nla_len <= (len)) diff --git a/ell/genl.h b/ell/genl.h index c628b8c..13fe149 100644 --- a/ell/genl.h +++ b/ell/genl.h @@ -71,6 +71,9 @@ int l_genl_msg_get_error(struct l_genl_msg *msg); bool l_genl_msg_append_attr(struct l_genl_msg *msg, uint16_t type, uint16_t len, const void *data); +bool l_genl_msg_append_init_recurse(struct l_genl_msg *msg, uint16_t type, + struct l_genl_attr *nested); +bool l_genl_msg_append_end_recurse(struct l_genl_attr *nested); bool l_genl_attr_init(struct l_genl_attr *attr, struct l_genl_msg *msg); bool l_genl_attr_next(struct l_genl_attr *attr, uint16_t *type, -- 2.0.5