[PATCH nft,v2 4/7] mnl: add mnl_nft_batch_to_msg()

[Pablo Neira Ayuso]

This function transforms the batch into a msghdr object.

Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org>
---
 src/mnl.c | 54 ++++++++++++++++++++++++++++++++++++------------------
 1 file changed, 36 insertions(+), 18 deletions(-)

diff --git a/src/mnl.c b/src/mnl.c
index b3999d5f1d9f..6c85b1855c86 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -257,49 +257,67 @@ static int mnl_set_rcvbuffer(const struct mnl_socket *nl, 
size_t bufsiz)
        return ret;
 }
 
-static ssize_t mnl_nft_socket_sendmsg(const struct netlink_ctx *ctx)
+static size_t mnl_nft_batch_to_msg(struct netlink_ctx *ctx, struct msghdr *msg,
+                                  const struct sockaddr_nl *snl,
+                                  struct iovec *iov, unsigned int iov_len)
 {
-       static const struct sockaddr_nl snl = {
-               .nl_family = AF_NETLINK
-       };
-       uint32_t iov_len = nftnl_batch_iovec_len(ctx->batch);
-       struct iovec iov[iov_len];
-       struct msghdr msg = {
-               .msg_name       = (struct sockaddr *) &snl,
-               .msg_namelen    = sizeof(snl),
-               .msg_iov        = iov,
-               .msg_iovlen     = iov_len,
-       };
-       uint32_t i;
+       unsigned int i;
+       size_t len = 0;
+
+       msg->msg_name           = (struct sockaddr_nl *)snl;
+       msg->msg_namelen        = sizeof(*snl);
+       msg->msg_iov            = iov;
+       msg->msg_iovlen         = iov_len;
 
        nftnl_batch_iovec(ctx->batch, iov, iov_len);
 
-       for (i = 0; i < iov_len; i++) {
-               if (ctx->nft->debug_mask & NFT_DEBUG_MNL) {
+       for (i = 0; i < iov_len; i++)
+               len += msg->msg_iov[i].iov_len;
+
+       return len;
+}
+
+static ssize_t mnl_nft_socket_sendmsg(struct netlink_ctx *ctx,
+                                     const struct msghdr *msg)
+{
+       uint32_t iov_len = msg->msg_iovlen;
+       struct iovec *iov = msg->msg_iov;
+       unsigned int i;
+
+       if (ctx->nft->debug_mask & NFT_DEBUG_MNL) {
+               for (i = 0; i < iov_len; i++) {
                        mnl_nlmsg_fprintf(ctx->nft->output.output_fp,
                                          iov[i].iov_base, iov[i].iov_len,
                                          sizeof(struct nfgenmsg));
                }
        }
 
-       return sendmsg(mnl_socket_get_fd(ctx->nft->nf_sock), &msg, 0);
+       return sendmsg(mnl_socket_get_fd(ctx->nft->nf_sock), msg, 0);
 }
 
 int mnl_batch_talk(struct netlink_ctx *ctx, struct list_head *err_list)
 {
        struct mnl_socket *nl = ctx->nft->nf_sock;
        int ret, fd = mnl_socket_get_fd(nl), portid = mnl_socket_get_portid(nl);
+       uint32_t iov_len = nftnl_batch_iovec_len(ctx->batch);
        char rcv_buf[MNL_SOCKET_BUFFER_SIZE];
-       fd_set readfds;
+       const struct sockaddr_nl snl = {
+               .nl_family = AF_NETLINK
+       };
        struct timeval tv = {
                .tv_sec         = 0,
                .tv_usec        = 0
        };
+       fd_set readfds;
+       struct iovec iov[iov_len];
+       struct msghdr msg = {};
        int err = 0;
 
        mnl_set_sndbuffer(ctx->nft->nf_sock, ctx->batch);
 
-       ret = mnl_nft_socket_sendmsg(ctx);
+       mnl_nft_batch_to_msg(ctx, &msg, &snl, iov, iov_len);
+
+       ret = mnl_nft_socket_sendmsg(ctx, &msg);
        if (ret == -1)
                return -1;
 
-- 
2.11.0