fixes #1713 SP pipe_send leaks message if aio is canceled

src/sp/transport/inproc/inproc.c

@@ -1,5 +1,5 @@
 //
-// Copyright 2020 Staysail Systems, Inc. <[email protected]>
+// Copyright 2023 Staysail Systems, Inc. <[email protected]>
 // Copyright 2018 Capitar IT Group BV <[email protected]>
 // Copyright 2018 Devolutions <[email protected]>
 //
@@ -207,6 +207,10 @@ inproc_pipe_send(void *arg, nni_aio *aio)
 	int           rv;
 
 	if (nni_aio_begin(aio) != 0) {
+		// No way to give the message back to the protocol, so
+		// we just discard it silently to prevent it from leaking.
+		nni_msg_free(nni_aio_get_msg(aio));
+		nni_aio_set_msg(aio, NULL);
 		return;
 	}
 

src/sp/transport/ipc/ipc.c

@@ -518,6 +518,10 @@ ipc_pipe_send(void *arg, nni_aio *aio)
 	int       rv;
 
 	if (nni_aio_begin(aio) != 0) {
+		// No way to give the message back to the protocol, so
+		// we just discard it silently to prevent it from leaking.
+		nni_msg_free(nni_aio_get_msg(aio));
+		nni_aio_set_msg(aio, NULL);
 		return;
 	}
 	nni_mtx_lock(&p->mtx);

src/sp/transport/tcp/tcp.c

@@ -1,5 +1,5 @@
 //
-// Copyright 2021 Staysail Systems, Inc. <[email protected]>
+// Copyright 2023 Staysail Systems, Inc. <[email protected]>
 // Copyright 2018 Capitar IT Group BV <[email protected]>
 // Copyright 2019 Devolutions <[email protected]>
 //
@@ -512,6 +512,10 @@ tcptran_pipe_send(void *arg, nni_aio *aio)
 	int           rv;
 
 	if (nni_aio_begin(aio) != 0) {
+		// No way to give the message back to the protocol, so
+		// we just discard it silently to prevent it from leaking.
+		nni_msg_free(nni_aio_get_msg(aio));
+		nni_aio_set_msg(aio, NULL);
 		return;
 	}
 	nni_mtx_lock(&p->mtx);

src/sp/transport/tls/tls.c

@@ -1,5 +1,5 @@
 //
-// Copyright 2021 Staysail Systems, Inc. <[email protected]>
+// Copyright 2023 Staysail Systems, Inc. <[email protected]>
 // Copyright 2018 Capitar IT Group BV <[email protected]>
 // Copyright 2019 Devolutions <[email protected]>
 //
@@ -498,6 +498,10 @@ tlstran_pipe_send(void *arg, nni_aio *aio)
 	int           rv;
 
 	if (nni_aio_begin(aio) != 0) {
+		// No way to give the message back to the protocol, so
+		// we just discard it silently to prevent it from leaking.
+		nni_msg_free(nni_aio_get_msg(aio));
+		nni_aio_set_msg(aio, NULL);
 		return;
 	}
 	nni_mtx_lock(&p->mtx);

src/sp/transport/ws/websocket.c

@@ -1,5 +1,5 @@
 //
-// Copyright 2020 Staysail Systems, Inc. <[email protected]>
+// Copyright 2023 Staysail Systems, Inc. <[email protected]>
 // Copyright 2018 Capitar IT Group BV <[email protected]>
 // Copyright 2019 Devolutions <[email protected]>
 //
@@ -158,6 +158,10 @@ wstran_pipe_send(void *arg, nni_aio *aio)
 	int      rv;
 
 	if (nni_aio_begin(aio) != 0) {
+		// No way to give the message back to the protocol, so
+		// we just discard it silently to prevent it from leaking.
+		nni_msg_free(nni_aio_get_msg(aio));
+		nni_aio_set_msg(aio, NULL);
 		return;
 	}
 	nni_mtx_lock(&p->mtx);

src/sp/transport/zerotier/zerotier.c

@@ -1,6 +1,6 @@
 //
+// Copyright 2023 Staysail Systems, Inc. <[email protected]>
 // Copyright 2021 Capitar IT Group BV <[email protected]>
-// Copyright 2020 Staysail Systems, Inc. <[email protected]>
 //
 // This software is supplied under the terms of the MIT License, a
 // copy of which should be located in the distribution where this
@@ -1821,6 +1821,10 @@ zt_pipe_send(void *arg, nni_aio *aio)
 	nni_msg *m;
 
 	if (nni_aio_begin(aio) != 0) {
+		// No way to give the message back to the protocol, so
+		// we just discard it silently to prevent it from leaking.
+		nni_msg_free(nni_aio_get_msg(aio));
+		nni_aio_set_msg(aio, NULL);
 		return;
 	}
 	if ((m = nni_aio_get_msg(aio)) == NULL) {