fixes #1345 Restructure the source tree

This is not quite complete, but it sets the stage for other
protocols (such as zmq or mqtt) to be added to the project.

1 files changed, 211 insertions, 0 deletions

diff --git a/src/sp/protocol/pubsub0/xsub.c b/src/sp/protocol/pubsub0/xsub.c
new file mode 100644
index 00000000..0013b8b3
--- /dev/null
+++ b/src/sp/protocol/pubsub0/xsub.c
@@ -0,0 +1,211 @@
+//
+// Copyright 2020 Staysail Systems, Inc. <info@staysail.tech>
+// Copyright 2018 Capitar IT Group BV <info@capitar.com>
+//
+// This software is supplied under the terms of the MIT License, a
+// copy of which should be located in the distribution where this
+// file was obtained (LICENSE.txt).  A copy of the license may also be
+// found online at https://opensource.org/licenses/MIT.
+//
+
+#include <stdlib.h>
+
+#include "core/nng_impl.h"
+#include "nng/protocol/pubsub0/sub.h"
+
+// Subscriber protocol.  The SUB protocol receives messages sent to
+// it from publishers, and filters out those it is not interested in,
+// only passing up ones that match known subscriptions.
+
+#ifndef NNI_PROTO_SUB_V0
+#define NNI_PROTO_SUB_V0 NNI_PROTO(2, 1)
+#endif
+
+#ifndef NNI_PROTO_PUB_V0
+#define NNI_PROTO_PUB_V0 NNI_PROTO(2, 0)
+#endif
+
+typedef struct xsub0_pipe xsub0_pipe;
+typedef struct xsub0_sock xsub0_sock;
+
+static void xsub0_recv_cb(void *);
+static void xsub0_pipe_fini(void *);
+
+// xsub0_sock is our per-socket protocol private structure.
+struct xsub0_sock {
+	nni_msgq *urq;
+	nni_mtx   lk;
+};
+
+// sub0_pipe is our per-pipe protocol private structure.
+struct xsub0_pipe {
+	nni_pipe *  pipe;
+	xsub0_sock *sub;
+	nni_aio    aio_recv;
+};
+
+static int
+xsub0_sock_init(void *arg, nni_sock *sock)
+{
+	xsub0_sock *s = arg;
+
+	s->urq = nni_sock_recvq(sock);
+	return (0);
+}
+
+static void
+xsub0_sock_fini(void *arg)
+{
+	xsub0_sock *s = arg;
+	nni_mtx_fini(&s->lk);
+}
+
+static void
+xsub0_sock_open(void *arg)
+{
+	NNI_ARG_UNUSED(arg);
+}
+
+static void
+xsub0_sock_close(void *arg)
+{
+	NNI_ARG_UNUSED(arg);
+}
+
+static void
+xsub0_pipe_stop(void *arg)
+{
+	xsub0_pipe *p = arg;
+
+	nni_aio_stop(&p->aio_recv);
+}
+
+static void
+xsub0_pipe_fini(void *arg)
+{
+	xsub0_pipe *p = arg;
+
+	nni_aio_fini(&p->aio_recv);
+}
+
+static int
+xsub0_pipe_init(void *arg, nni_pipe *pipe, void *s)
+{
+	xsub0_pipe *p = arg;
+
+	nni_aio_init(&p->aio_recv, xsub0_recv_cb, p);
+
+	p->pipe = pipe;
+	p->sub  = s;
+	return (0);
+}
+
+static int
+xsub0_pipe_start(void *arg)
+{
+	xsub0_pipe *p = arg;
+
+	if (nni_pipe_peer(p->pipe) != NNI_PROTO_PUB_V0) {
+		// Peer protocol mismatch.
+		return (NNG_EPROTO);
+	}
+
+	nni_pipe_recv(p->pipe, &p->aio_recv);
+	return (0);
+}
+
+static void
+xsub0_pipe_close(void *arg)
+{
+	xsub0_pipe *p = arg;
+
+	nni_aio_close(&p->aio_recv);
+}
+
+static void
+xsub0_recv_cb(void *arg)
+{
+	xsub0_pipe *p   = arg;
+	xsub0_sock *s   = p->sub;
+	nni_msgq *  urq = s->urq;
+	nni_msg *   msg;
+
+	if (nni_aio_result(&p->aio_recv) != 0) {
+		nni_pipe_close(p->pipe);
+		return;
+	}
+
+	msg = nni_aio_get_msg(&p->aio_recv);
+	nni_aio_set_msg(&p->aio_recv, NULL);
+	nni_msg_set_pipe(msg, nni_pipe_id(p->pipe));
+
+	if (nni_msgq_tryput(urq, msg) != 0) {
+		// This only happens for two reasons.  For flow control,
+		// in which case we just want to discard the message and
+		// carry on, and for a close of the socket (which is very
+		// hard to achieve, since we close the pipes.)  In either
+		// case the easiest thing to do is just free the message
+		// and try again.
+		nni_msg_free(msg);
+	}
+	nni_pipe_recv(p->pipe, &p->aio_recv);
+}
+
+static void
+xsub0_sock_send(void *arg, nni_aio *aio)
+{
+	NNI_ARG_UNUSED(arg);
+	nni_aio_finish_error(aio, NNG_ENOTSUP);
+}
+
+static void
+xsub0_sock_recv(void *arg, nni_aio *aio)
+{
+	xsub0_sock *s = arg;
+
+	nni_msgq_aio_get(s->urq, aio);
+}
+
+// This is the global protocol structure -- our linkage to the core.
+// This should be the only global non-static symbol in this file.
+static nni_proto_pipe_ops xsub0_pipe_ops = {
+	.pipe_size  = sizeof(xsub0_pipe),
+	.pipe_init  = xsub0_pipe_init,
+	.pipe_fini  = xsub0_pipe_fini,
+	.pipe_start = xsub0_pipe_start,
+	.pipe_close = xsub0_pipe_close,
+	.pipe_stop  = xsub0_pipe_stop,
+};
+
+static nni_option xsub0_sock_options[] = {
+	// terminate list
+	{
+	    .o_name = NULL,
+	},
+};
+
+static nni_proto_sock_ops xsub0_sock_ops = {
+	.sock_size    = sizeof(xsub0_sock),
+	.sock_init    = xsub0_sock_init,
+	.sock_fini    = xsub0_sock_fini,
+	.sock_open    = xsub0_sock_open,
+	.sock_close   = xsub0_sock_close,
+	.sock_send    = xsub0_sock_send,
+	.sock_recv    = xsub0_sock_recv,
+	.sock_options = xsub0_sock_options,
+};
+
+static nni_proto xsub0_proto = {
+	.proto_version  = NNI_PROTOCOL_VERSION,
+	.proto_self     = { NNI_PROTO_SUB_V0, "sub" },
+	.proto_peer     = { NNI_PROTO_PUB_V0, "pub" },
+	.proto_flags    = NNI_PROTO_FLAG_RCV | NNI_PROTO_FLAG_RAW,
+	.proto_sock_ops = &xsub0_sock_ops,
+	.proto_pipe_ops = &xsub0_pipe_ops,
+};
+
+int
+nng_sub0_open_raw(nng_socket *sidp)
+{
+	return (nni_proto_open(sidp, &xsub0_proto));
+}