1 files changed, 383 insertions, 0 deletions
diff --git a/src/sp/protocol/pubsub0/pub.c b/src/sp/protocol/pubsub0/pub.c
new file mode 100644
index 00000000..e3d4f16a
--- /dev/null
+++ b/src/sp/protocol/pubsub0/pub.c
@@ -0,0 +1,383 @@
+//
+// 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 <string.h>
+
+#include "core/nng_impl.h"
+#include "nng/protocol/pubsub0/pub.h"
+
+// Publish protocol.  The PUB protocol simply sends messages out, as
+// a broadcast.  It has nothing more sophisticated because it does not
+// perform sender-side filtering.  Its best effort delivery, so anything
+// that can't receive the message won't get one.
+
+#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 pub0_pipe pub0_pipe;
+typedef struct pub0_sock pub0_sock;
+
+static void pub0_pipe_recv_cb(void *);
+static void pub0_pipe_send_cb(void *);
+static void pub0_sock_fini(void *);
+static void pub0_pipe_fini(void *);
+
+// pub0_sock is our per-socket protocol private structure.
+struct pub0_sock {
+	nni_list      pipes;
+	nni_mtx       mtx;
+	bool          closed;
+	size_t        sendbuf;
+	nni_pollable *sendable;
+};
+
+// pub0_pipe is our per-pipe protocol private structure.
+struct pub0_pipe {
+	nni_pipe *    pipe;
+	pub0_sock *   pub;
+	nni_lmq       sendq;
+	bool          closed;
+	bool          busy;
+	nni_aio *     aio_send;
+	nni_aio *     aio_recv;
+	nni_list_node node;
+};
+
+static void
+pub0_sock_fini(void *arg)
+{
+	pub0_sock *s = arg;
+
+	nni_pollable_free(s->sendable);
+	nni_mtx_fini(&s->mtx);
+}
+
+static int
+pub0_sock_init(void *arg, nni_sock *nsock)
+{
+	pub0_sock *sock = arg;
+	int        rv;
+	NNI_ARG_UNUSED(nsock);
+
+	if ((rv = nni_pollable_alloc(&sock->sendable)) != 0) {
+		return (rv);
+	}
+	nni_mtx_init(&sock->mtx);
+	NNI_LIST_INIT(&sock->pipes, pub0_pipe, node);
+	sock->sendbuf = 16; // fairly arbitrary
+	return (0);
+}
+
+static void
+pub0_sock_open(void *arg)
+{
+	NNI_ARG_UNUSED(arg);
+}
+
+static void
+pub0_sock_close(void *arg)
+{
+	NNI_ARG_UNUSED(arg);
+}
+
+static void
+pub0_pipe_stop(void *arg)
+{
+	pub0_pipe *p = arg;
+
+	nni_aio_stop(p->aio_send);
+	nni_aio_stop(p->aio_recv);
+}
+
+static void
+pub0_pipe_fini(void *arg)
+{
+	pub0_pipe *p = arg;
+
+	nni_aio_free(p->aio_send);
+	nni_aio_free(p->aio_recv);
+	nni_lmq_fini(&p->sendq);
+}
+
+static int
+pub0_pipe_init(void *arg, nni_pipe *pipe, void *s)
+{
+	pub0_pipe *p    = arg;
+	pub0_sock *sock = s;
+	int        rv;
+	size_t     len;
+
+	nni_mtx_lock(&sock->mtx);
+	len = sock->sendbuf;
+	nni_mtx_unlock(&sock->mtx);
+
+	// XXX: consider making this depth tunable
+	if (((rv = nni_lmq_init(&p->sendq, len)) != 0) ||
+	    ((rv = nni_aio_alloc(&p->aio_send, pub0_pipe_send_cb, p)) != 0) ||
+	    ((rv = nni_aio_alloc(&p->aio_recv, pub0_pipe_recv_cb, p)) != 0)) {
+
+		pub0_pipe_fini(p);
+		return (rv);
+	}
+
+	p->busy = false;
+	p->pipe = pipe;
+	p->pub  = s;
+	return (0);
+}
+
+static int
+pub0_pipe_start(void *arg)
+{
+	pub0_pipe *p    = arg;
+	pub0_sock *sock = p->pub;
+
+	if (nni_pipe_peer(p->pipe) != NNI_PROTO_SUB_V0) {
+		return (NNG_EPROTO);
+	}
+	nni_mtx_lock(&sock->mtx);
+	nni_list_append(&sock->pipes, p);
+	nni_mtx_unlock(&sock->mtx);
+
+	// Start the receiver.
+	nni_pipe_recv(p->pipe, p->aio_recv);
+
+	return (0);
+}
+
+static void
+pub0_pipe_close(void *arg)
+{
+	pub0_pipe *p    = arg;
+	pub0_sock *sock = p->pub;
+
+	nni_aio_close(p->aio_send);
+	nni_aio_close(p->aio_recv);
+
+	nni_mtx_lock(&sock->mtx);
+	p->closed = true;
+	nni_lmq_flush(&p->sendq);
+
+	if (nni_list_active(&sock->pipes, p)) {
+		nni_list_remove(&sock->pipes, p);
+	}
+	nni_mtx_unlock(&sock->mtx);
+}
+
+static void
+pub0_pipe_recv_cb(void *arg)
+{
+	pub0_pipe *p = arg;
+
+	// We should never receive a message -- the only valid reason for us to
+	// be here is on pipe close.
+	if (nni_aio_result(p->aio_recv) == 0) {
+		nni_msg_free(nni_aio_get_msg(p->aio_recv));
+	}
+	nni_pipe_close(p->pipe);
+}
+
+static void
+pub0_pipe_send_cb(void *arg)
+{
+	pub0_pipe *p    = arg;
+	pub0_sock *sock = p->pub;
+	nni_msg *  msg;
+
+	if (nni_aio_result(p->aio_send) != 0) {
+		nni_msg_free(nni_aio_get_msg(p->aio_send));
+		nni_aio_set_msg(p->aio_send, NULL);
+		nni_pipe_close(p->pipe);
+		return;
+	}
+
+	nni_mtx_lock(&sock->mtx);
+	if (p->closed) {
+		nni_mtx_unlock(&sock->mtx);
+		return;
+	}
+	if (nni_lmq_getq(&p->sendq, &msg) == 0) {
+		nni_aio_set_msg(p->aio_send, msg);
+		nni_pipe_send(p->pipe, p->aio_send);
+	} else {
+		p->busy = false;
+	}
+	nni_mtx_unlock(&sock->mtx);
+}
+
+static void
+pub0_sock_recv(void *arg, nni_aio *aio)
+{
+	NNI_ARG_UNUSED(arg);
+	if (nni_aio_begin(aio) == 0) {
+		nni_aio_finish_error(aio, NNG_ENOTSUP);
+	}
+}
+
+static void
+pub0_sock_send(void *arg, nni_aio *aio)
+{
+	pub0_sock *sock = arg;
+	pub0_pipe *p;
+	nng_msg *  msg;
+	size_t     len;
+
+	msg = nni_aio_get_msg(aio);
+	len = nni_msg_len(msg);
+	nni_mtx_lock(&sock->mtx);
+	NNI_LIST_FOREACH (&sock->pipes, p) {
+
+		nni_msg_clone(msg);
+		if (p->busy) {
+			if (nni_lmq_full(&p->sendq)) {
+				// Make space for the new message.
+				nni_msg *old;
+				(void) nni_lmq_getq(&p->sendq, &old);
+				nni_msg_free(old);
+			}
+			nni_lmq_putq(&p->sendq, msg);
+		} else {
+			p->busy = true;
+			nni_aio_set_msg(p->aio_send, msg);
+			nni_pipe_send(p->pipe, p->aio_send);
+		}
+	}
+	nni_mtx_unlock(&sock->mtx);
+	nng_msg_free(msg);
+	nni_aio_finish(aio, 0, len);
+}
+
+static int
+pub0_sock_get_sendfd(void *arg, void *buf, size_t *szp, nni_type t)
+{
+	pub0_sock *sock = arg;
+	int        fd;
+	int        rv;
+	nni_mtx_lock(&sock->mtx);
+	// PUB sockets are *always* writable.
+	nni_pollable_raise(sock->sendable);
+	rv = nni_pollable_getfd(sock->sendable, &fd);
+	nni_mtx_unlock(&sock->mtx);
+
+	if (rv == 0) {
+		rv = nni_copyout_int(fd, buf, szp, t);
+	}
+	return (rv);
+}
+
+static int
+pub0_sock_set_sendbuf(void *arg, const void *buf, size_t sz, nni_type t)
+{
+	pub0_sock *sock = arg;
+	pub0_pipe *p;
+	int        val;
+	int        rv;
+
+	if ((rv = nni_copyin_int(&val, buf, sz, 1, 8192, t)) != 0) {
+		return (rv);
+	}
+
+	nni_mtx_lock(&sock->mtx);
+	sock->sendbuf = (size_t) val;
+	NNI_LIST_FOREACH (&sock->pipes, p) {
+		// If we fail part way thru (should only be ENOMEM), we
+		// stop short.  The others would likely fail for ENOMEM as
+		// well anyway.  There is a weird effect here where the
+		// buffers may have been set for *some* of the pipes, but
+		// we have no way to correct partial failure.
+		if ((rv = nni_lmq_resize(&p->sendq, (size_t) val)) != 0) {
+			break;
+		}
+	}
+	nni_mtx_unlock(&sock->mtx);
+	return (rv);
+}
+
+static int
+pub0_sock_get_sendbuf(void *arg, void *buf, size_t *szp, nni_type t)
+{
+	pub0_sock *sock = arg;
+	int        val;
+	nni_mtx_lock(&sock->mtx);
+	val = (int) sock->sendbuf;
+	nni_mtx_unlock(&sock->mtx);
+	return (nni_copyout_int(val, buf, szp, t));
+}
+
+static nni_proto_pipe_ops pub0_pipe_ops = {
+	.pipe_size  = sizeof(pub0_pipe),
+	.pipe_init  = pub0_pipe_init,
+	.pipe_fini  = pub0_pipe_fini,
+	.pipe_start = pub0_pipe_start,
+	.pipe_close = pub0_pipe_close,
+	.pipe_stop  = pub0_pipe_stop,
+};
+
+static nni_option pub0_sock_options[] = {
+	// terminate list
+	{
+	    .o_name = NNG_OPT_SENDFD,
+	    .o_get  = pub0_sock_get_sendfd,
+	},
+	{
+	    .o_name = NNG_OPT_SENDBUF,
+	    .o_get  = pub0_sock_get_sendbuf,
+	    .o_set  = pub0_sock_set_sendbuf,
+	},
+	{
+	    .o_name = NULL,
+	},
+};
+
+static nni_proto_sock_ops pub0_sock_ops = {
+	.sock_size    = sizeof(pub0_sock),
+	.sock_init    = pub0_sock_init,
+	.sock_fini    = pub0_sock_fini,
+	.sock_open    = pub0_sock_open,
+	.sock_close   = pub0_sock_close,
+	.sock_send    = pub0_sock_send,
+	.sock_recv    = pub0_sock_recv,
+	.sock_options = pub0_sock_options,
+};
+
+static nni_proto pub0_proto = {
+	.proto_version  = NNI_PROTOCOL_VERSION,
+	.proto_self     = { NNI_PROTO_PUB_V0, "pub" },
+	.proto_peer     = { NNI_PROTO_SUB_V0, "sub" },
+	.proto_flags    = NNI_PROTO_FLAG_SND,
+	.proto_sock_ops = &pub0_sock_ops,
+	.proto_pipe_ops = &pub0_pipe_ops,
+};
+
+static nni_proto pub0_proto_raw = {
+	.proto_version  = NNI_PROTOCOL_VERSION,
+	.proto_self     = { NNI_PROTO_PUB_V0, "pub" },
+	.proto_peer     = { NNI_PROTO_SUB_V0, "sub" },
+	.proto_flags    = NNI_PROTO_FLAG_SND | NNI_PROTO_FLAG_RAW,
+	.proto_sock_ops = &pub0_sock_ops,
+	.proto_pipe_ops = &pub0_pipe_ops,
+};
+
+int
+nng_pub0_open(nng_socket *sidp)
+{
+	return (nni_proto_open(sidp, &pub0_proto));
+}
+
+int
+nng_pub0_open_raw(nng_socket *sidp)
+{
+	return (nni_proto_open(sidp, &pub0_proto_raw));
+}