[PATCH libnetfilter_queue v2] src: move static nfq_hdr_put from examples/nf-queue.c into the library since everyone is going to want it.

[Duncan Roe <duncan_roe@optusnet.com.au>]

Also rename nfq_hdr_put to nfq_nlmsg_put

Signed-off-by: Duncan Roe <duncan_roe@optusnet.com.au>

v2: Rename nfq_hdr_put to nfq_nlmsg_put on Pablo's suggestion
---
 examples/nf-queue.c                             | 21 +++----------------
 include/libnetfilter_queue/libnetfilter_queue.h |  1 +
 src/nlmsg.c                                     | 28 ++++++++++++++++++++++---
 3 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/examples/nf-queue.c b/examples/nf-queue.c
index 960e244..3da2c24 100644
--- a/examples/nf-queue.c
+++ b/examples/nf-queue.c
@@ -20,21 +20,6 @@
 
 static struct mnl_socket *nl;
 
-static struct nlmsghdr *
-nfq_hdr_put(char *buf, int type, uint32_t queue_num)
-{
-	struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf);
-	nlh->nlmsg_type	= (NFNL_SUBSYS_QUEUE << 8) | type;
-	nlh->nlmsg_flags = NLM_F_REQUEST;
-
-	struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg));
-	nfg->nfgen_family = AF_UNSPEC;
-	nfg->version = NFNETLINK_V0;
-	nfg->res_id = htons(queue_num);
-
-	return nlh;
-}
-
 static void
 nfq_send_verdict(int queue_num, uint32_t id)
 {
@@ -42,7 +27,7 @@ nfq_send_verdict(int queue_num, uint32_t id)
 	struct nlmsghdr *nlh;
 	struct nlattr *nest;
 
-	nlh = nfq_hdr_put(buf, NFQNL_MSG_VERDICT, queue_num);
+	nlh = nfq_nlmsg_put(buf, NFQNL_MSG_VERDICT, queue_num);
 	nfq_nlmsg_verdict_put(nlh, id, NF_ACCEPT);
 
 	/* example to set the connmark. First, start NFQA_CT section: */
@@ -150,7 +135,7 @@ int main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	nlh = nfq_hdr_put(buf, NFQNL_MSG_CONFIG, queue_num);
+	nlh = nfq_nlmsg_put(buf, NFQNL_MSG_CONFIG, queue_num);
 	nfq_nlmsg_cfg_put_cmd(nlh, AF_INET, NFQNL_CFG_CMD_BIND);
 
 	if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
@@ -158,7 +143,7 @@ int main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	nlh = nfq_hdr_put(buf, NFQNL_MSG_CONFIG, queue_num);
+	nlh = nfq_nlmsg_put(buf, NFQNL_MSG_CONFIG, queue_num);
 	nfq_nlmsg_cfg_put_params(nlh, NFQNL_COPY_PACKET, 0xffff);
 
 	mnl_attr_put_u32(nlh, NFQA_CFG_FLAGS, htonl(NFQA_CFG_F_GSO));
diff --git a/include/libnetfilter_queue/libnetfilter_queue.h b/include/libnetfilter_queue/libnetfilter_queue.h
index 092c57d..34385a7 100644
--- a/include/libnetfilter_queue/libnetfilter_queue.h
+++ b/include/libnetfilter_queue/libnetfilter_queue.h
@@ -149,6 +149,7 @@ void nfq_nlmsg_verdict_put_mark(struct nlmsghdr *nlh, uint32_t mark);
 void nfq_nlmsg_verdict_put_pkt(struct nlmsghdr *nlh, const void *pkt, uint32_t pktlen);
 
 int nfq_nlmsg_parse(const struct nlmsghdr *nlh, struct nlattr **attr);
+struct nlmsghdr *nfq_nlmsg_put(char *buf, int type, uint32_t queue_num);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/src/nlmsg.c b/src/nlmsg.c
index 4f09bf6..e141156 100644
--- a/src/nlmsg.c
+++ b/src/nlmsg.c
@@ -261,9 +261,9 @@ static int nfq_pkt_parse_attr_cb(const struct nlattr *attr, void *data)
 
 /**
  * nfq_nlmsg_parse - set packet attributes from netlink message
- * \param nlh netlink message that you want to read.
- * \param attr pointer to array of attributes to set.
- * \returns MNL_CB_OK on success or MNL_CB_ERROR if any error occurs.
+ * \param nlh Pointer to netlink message
+ * \param attr Pointer to array of attributes to set
+ * \returns MNL_CB_OK on success or MNL_CB_ERROR if any error occurs
  */
 EXPORT_SYMBOL
 int nfq_nlmsg_parse(const struct nlmsghdr *nlh, struct nlattr **attr)
@@ -272,6 +272,28 @@ int nfq_nlmsg_parse(const struct nlmsghdr *nlh, struct nlattr **attr)
 			      nfq_pkt_parse_attr_cb, attr);
 }
 
+/**
+ * nfq_nlmsg_put - Convert memory buffer into a Netlink buffer
+ * \param *buf Pointer to memory buffer
+ * \param type Either NFQNL_MSG_CONFIG or NFQNL_MSG_VERDICT
+ * \param queue_num Queue number
+ * \returns Pointer to netlink message
+ */
+EXPORT_SYMBOL
+struct nlmsghdr *nfq_nlmsg_put(char *buf, int type, uint32_t queue_num)
+{
+	struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf);
+	nlh->nlmsg_type = (NFNL_SUBSYS_QUEUE << 8) | type;
+	nlh->nlmsg_flags = NLM_F_REQUEST;
+
+	struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg));
+	nfg->nfgen_family = AF_UNSPEC;
+	nfg->version = NFNETLINK_V0;
+	nfg->res_id = htons(queue_num);
+
+	return nlh;
+}
+
 /**
  * @}
  */
-- 
2.14.5