diff options
Diffstat (limited to 'src/sp/protocol/pubsub0/xsub.c')
| -rw-r--r-- | src/sp/protocol/pubsub0/xsub.c | 211 |
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)); +} |