added function tcp_listen_with_backlog_and_err() to get the error reason when listening fails (bug #49861)
diff --git a/CHANGELOG b/CHANGELOG
index 4371f02..051f7ae 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -6,8 +6,12 @@
++ New features:
+ 2016-12-31: Simon Goldschmidt
+ * tcp.h/.c: added function tcp_listen_with_backlog_and_err() to get the error
+ reason when listening fails (bug #49861)
+
2016-12-14: Jan Breuer:
- opt.h, ndc.h/.c: add support for RDNSS option (as per RFC 6106)
+ * opt.h, ndc.h/.c: add support for RDNSS option (as per RFC 6106)
2016-12-14: David van Moolenbroek
* opt.h, nd6.c: Added LWIP_HOOK_ND6_GET_GW()
diff --git a/src/api/api_msg.c b/src/api/api_msg.c
index 1009228..4927ee5 100644
--- a/src/api/api_msg.c
+++ b/src/api/api_msg.c
@@ -1307,6 +1307,13 @@
/* connection is not closed, cannot listen */
msg->err = ERR_VAL;
} else {
+ err_t err;
+ u8_t backlog;
+#if TCP_LISTEN_BACKLOG
+ backlog = msg->msg.lb.backlog;
+#else /* TCP_LISTEN_BACKLOG */
+ backlog = TCP_DEFAULT_LISTEN_BACKLOG;
+#endif /* TCP_LISTEN_BACKLOG */
#if LWIP_IPV4 && LWIP_IPV6
/* "Socket API like" dual-stack support: If IP to listen to is IP6_ADDR_ANY,
* and NETCONN_FLAG_IPV6_V6ONLY is NOT set, use IP_ANY_TYPE to listen
@@ -1319,15 +1326,11 @@
}
#endif /* LWIP_IPV4 && LWIP_IPV6 */
-#if TCP_LISTEN_BACKLOG
- lpcb = tcp_listen_with_backlog(msg->conn->pcb.tcp, msg->msg.lb.backlog);
-#else /* TCP_LISTEN_BACKLOG */
- lpcb = tcp_listen(msg->conn->pcb.tcp);
-#endif /* TCP_LISTEN_BACKLOG */
+ lpcb = tcp_listen_with_backlog_and_err(msg->conn->pcb.tcp, backlog, &err);
if (lpcb == NULL) {
/* in this case, the old pcb is still allocated */
- msg->err = ERR_MEM;
+ msg->err = err;
} else {
/* delete the recvmbox and allocate the acceptmbox */
if (sys_mbox_valid(&msg->conn->recvmbox)) {
diff --git a/src/core/tcp.c b/src/core/tcp.c
index f72597b..63e4445 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -636,19 +636,44 @@
*
* @note The original tcp_pcb is freed. This function therefore has to be
* called like this:
- * tpcb = tcp_listen(tpcb);
+ * tpcb = tcp_listen_with_backlog(tpcb, backlog);
*/
struct tcp_pcb *
tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
{
- struct tcp_pcb_listen *lpcb;
+ return tcp_listen_with_backlog_and_err(pcb, backlog, NULL);
+}
+
+/**
+ * @ingroup tcp_raw
+ * Set the state of the connection to be LISTEN, which means that it
+ * is able to accept incoming connections. The protocol control block
+ * is reallocated in order to consume less memory. Setting the
+ * connection to LISTEN is an irreversible process.
+ *
+ * @param pcb the original tcp_pcb
+ * @param backlog the incoming connections queue limit
+ * @param err when NULL is returned, this contains the error reason
+ * @return tcp_pcb used for listening, consumes less memory.
+ *
+ * @note The original tcp_pcb is freed. This function therefore has to be
+ * called like this:
+ * tpcb = tcp_listen_with_backlog_and_err(tpcb, backlog, &err);
+ */
+struct tcp_pcb *
+tcp_listen_with_backlog_and_err(struct tcp_pcb *pcb, u8_t backlog, err_t *err)
+{
+ struct tcp_pcb_listen *lpcb = NULL;
+ err_t res;
LWIP_UNUSED_ARG(backlog);
- LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
+ LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, res = ERR_CLSD; goto done);
/* already listening? */
if (pcb->state == LISTEN) {
- return pcb;
+ lpcb = (struct tcp_pcb_listen*)pcb;
+ res = ERR_ALREADY;
+ goto done;
}
#if SO_REUSE
if (ip_get_option(pcb, SOF_REUSEADDR)) {
@@ -659,14 +684,16 @@
if ((lpcb->local_port == pcb->local_port) &&
ip_addr_cmp(&lpcb->local_ip, &pcb->local_ip)) {
/* this address/port is already used */
- return NULL;
+ res = ERR_USE;
+ goto done;
}
}
}
#endif /* SO_REUSE */
lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);
if (lpcb == NULL) {
- return NULL;
+ res = ERR_MEM;
+ goto done;
}
lpcb->callback_arg = pcb->callback_arg;
lpcb->local_port = pcb->local_port;
@@ -691,6 +718,11 @@
tcp_backlog_set(lpcb, backlog);
#endif /* TCP_LISTEN_BACKLOG */
TCP_REG(&tcp_listen_pcbs.pcbs, (struct tcp_pcb *)lpcb);
+ res = ERR_OK;
+done:
+ if (err != NULL) {
+ *err = res;
+ }
return (struct tcp_pcb *)lpcb;
}
diff --git a/src/include/lwip/tcp.h b/src/include/lwip/tcp.h
index 35584b4..3fd4467 100644
--- a/src/include/lwip/tcp.h
+++ b/src/include/lwip/tcp.h
@@ -387,6 +387,7 @@
err_t tcp_connect (struct tcp_pcb *pcb, const ip_addr_t *ipaddr,
u16_t port, tcp_connected_fn connected);
+struct tcp_pcb * tcp_listen_with_backlog_and_err(struct tcp_pcb *pcb, u8_t backlog, err_t *err);
struct tcp_pcb * tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog);
/** @ingroup tcp_raw */
#define tcp_listen(pcb) tcp_listen_with_backlog(pcb, TCP_DEFAULT_LISTEN_BACKLOG)
