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#ifndef __ZMQ_FQ_HPP_INCLUDED__
31#define __ZMQ_FQ_HPP_INCLUDED__
32
33#include "array.hpp"
34#include "blob.hpp"
35
36namespace zmq
37{
38class msg_t;
39class pipe_t;
40
41// Class manages a set of inbound pipes. On receive it performs fair
42// queueing so that senders gone berserk won't cause denial of
43// service for decent senders.
44
45class fq_t
46{
47 public:
48 fq_t ();
49 ~fq_t ();
50
51 void attach (pipe_t *pipe_);
52 void activated (pipe_t *pipe_);
53 void pipe_terminated (pipe_t *pipe_);
54
55 int recv (msg_t *msg_);
56 int recvpipe (msg_t *msg_, pipe_t **pipe_);
57 bool has_in ();
58
59 private:
60 // Inbound pipes.
61 typedef array_t<pipe_t, 1> pipes_t;
62 pipes_t _pipes;
63
64 // Number of active pipes. All the active pipes are located at the
65 // beginning of the pipes array.
66 pipes_t::size_type _active;
67
68 // Pointer to the last pipe we received message from.
69 // NULL when no message has been received or the pipe
70 // has terminated.
71 pipe_t *_last_in;
72
73 // Index of the next bound pipe to read a message from.
74 pipes_t::size_type _current;
75
76 // If true, part of a multipart message was already received, but
77 // there are following parts still waiting in the current pipe.
78 bool _more;
79
80 ZMQ_NON_COPYABLE_NOR_MOVABLE (fq_t)
81};
82}
83
84#endif
85