1/*
2 Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
3
4 This file is part of libzmq, the ZeroMQ core engine in C++.
5
6 libzmq is free software; you can redistribute it and/or modify it under
7 the terms of the GNU Lesser General Public License (LGPL) as published
8 by the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 As a special exception, the Contributors give you permission to link
12 this library with independent modules to produce an executable,
13 regardless of the license terms of these independent modules, and to
14 copy and distribute the resulting executable under terms of your choice,
15 provided that you also meet, for each linked independent module, the
16 terms and conditions of the license of that module. An independent
17 module is a module which is not derived from or based on this library.
18 If you modify this library, you must extend this exception to your
19 version of the library.
20
21 libzmq is distributed in the hope that it will be useful, but WITHOUT
22 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
23 FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
24 License for more details.
25
26 You should have received a copy of the GNU Lesser General Public License
27 along with this program. If not, see <http://www.gnu.org/licenses/>.
28*/
29
30#include "precompiled.hpp"
31#include "sub.hpp"
32#include "msg.hpp"
33
34zmq::sub_t::sub_t (class ctx_t *parent_, uint32_t tid_, int sid_) :
35 xsub_t (parent_, tid_, sid_)
36{
37 options.type = ZMQ_SUB;
38
39 // Switch filtering messages on (as opposed to XSUB which where the
40 // filtering is off).
41 options.filter = true;
42}
43
44zmq::sub_t::~sub_t ()
45{
46}
47
48int zmq::sub_t::xsetsockopt (int option_,
49 const void *optval_,
50 size_t optvallen_)
51{
52 if (option_ != ZMQ_SUBSCRIBE && option_ != ZMQ_UNSUBSCRIBE) {
53 errno = EINVAL;
54 return -1;
55 }
56
57 // Create the subscription message.
58 msg_t msg;
59 int rc = msg.init_size (optvallen_ + 1);
60 errno_assert (rc == 0);
61 unsigned char *data = static_cast<unsigned char *> (msg.data ());
62 *data = (option_ == ZMQ_SUBSCRIBE);
63 // We explicitly allow a NULL subscription with size zero
64 if (optvallen_) {
65 assert (optval_);
66 memcpy (data + 1, optval_, optvallen_);
67 }
68 // Pass it further on in the stack.
69 rc = xsub_t::xsend (&msg);
70 return close_and_return (&msg, rc);
71}
72
73int zmq::sub_t::xsend (msg_t *)
74{
75 // Override the XSUB's send.
76 errno = ENOTSUP;
77 return -1;
78}
79
80bool zmq::sub_t::xhas_out ()
81{
82 // Override the XSUB's send.
83 return false;
84}
85