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 "stream_connecter_base.hpp"
32#include "session_base.hpp"
33#include "address.hpp"
34#include "random.hpp"
35#include "zmtp_engine.hpp"
36#include "raw_engine.hpp"
37
38#ifndef ZMQ_HAVE_WINDOWS
39#include <unistd.h>
40#else
41#include <winsock2.h>
42#endif
43
44#include <limits>
45
46zmq::stream_connecter_base_t::stream_connecter_base_t (
47 zmq::io_thread_t *io_thread_,
48 zmq::session_base_t *session_,
49 const zmq::options_t &options_,
50 zmq::address_t *addr_,
51 bool delayed_start_) :
52 own_t (io_thread_, options_),
53 io_object_t (io_thread_),
54 _addr (addr_),
55 _s (retired_fd),
56 _handle (static_cast<handle_t> (NULL)),
57 _socket (session_->get_socket ()),
58 _session (session_),
59 _delayed_start (delayed_start_),
60 _reconnect_timer_started (false),
61 _current_reconnect_ivl (options.reconnect_ivl)
62{
63 zmq_assert (_addr);
64 _addr->to_string (_endpoint);
65 // TODO the return value is unused! what if it fails? if this is impossible
66 // or does not matter, change such that endpoint in initialized using an
67 // initializer, and make endpoint const
68}
69
70zmq::stream_connecter_base_t::~stream_connecter_base_t ()
71{
72 zmq_assert (!_reconnect_timer_started);
73 zmq_assert (!_handle);
74 zmq_assert (_s == retired_fd);
75}
76
77void zmq::stream_connecter_base_t::process_plug ()
78{
79 if (_delayed_start)
80 add_reconnect_timer ();
81 else
82 start_connecting ();
83}
84
85void zmq::stream_connecter_base_t::process_term (int linger_)
86{
87 if (_reconnect_timer_started) {
88 cancel_timer (reconnect_timer_id);
89 _reconnect_timer_started = false;
90 }
91
92 if (_handle) {
93 rm_handle ();
94 }
95
96 if (_s != retired_fd)
97 close ();
98
99 own_t::process_term (linger_);
100}
101
102void zmq::stream_connecter_base_t::add_reconnect_timer ()
103{
104 if (options.reconnect_ivl != -1) {
105 const int interval = get_new_reconnect_ivl ();
106 add_timer (interval, reconnect_timer_id);
107 _socket->event_connect_retried (
108 make_unconnected_connect_endpoint_pair (_endpoint), interval);
109 _reconnect_timer_started = true;
110 }
111}
112
113int zmq::stream_connecter_base_t::get_new_reconnect_ivl ()
114{
115 // TODO should the random jitter be really based on the configured initial
116 // reconnect interval options.reconnect_ivl, or better on the
117 // _current_reconnect_ivl?
118
119 // The new interval is the current interval + random value.
120 const int random_jitter = generate_random () % options.reconnect_ivl;
121 const int interval =
122 _current_reconnect_ivl < std::numeric_limits<int>::max () - random_jitter
123 ? _current_reconnect_ivl + random_jitter
124 : std::numeric_limits<int>::max ();
125
126 // Only change the new current reconnect interval if the maximum reconnect
127 // interval was set and if it's larger than the reconnect interval.
128 if (options.reconnect_ivl_max > 0
129 && options.reconnect_ivl_max > options.reconnect_ivl) {
130 // Calculate the next interval
131 _current_reconnect_ivl =
132 _current_reconnect_ivl < std::numeric_limits<int>::max () / 2
133 ? std::min (_current_reconnect_ivl * 2, options.reconnect_ivl_max)
134 : options.reconnect_ivl_max;
135 }
136
137 return interval;
138}
139
140void zmq::stream_connecter_base_t::rm_handle ()
141{
142 rm_fd (_handle);
143 _handle = static_cast<handle_t> (NULL);
144}
145
146void zmq::stream_connecter_base_t::close ()
147{
148 // TODO before, this was an assertion for _s != retired_fd, but this does not match usage of close
149 if (_s != retired_fd) {
150#ifdef ZMQ_HAVE_WINDOWS
151 const int rc = closesocket (_s);
152 wsa_assert (rc != SOCKET_ERROR);
153#else
154 const int rc = ::close (_s);
155 errno_assert (rc == 0);
156#endif
157 _socket->event_closed (
158 make_unconnected_connect_endpoint_pair (_endpoint), _s);
159 _s = retired_fd;
160 }
161}
162
163void zmq::stream_connecter_base_t::in_event ()
164{
165 // We are not polling for incoming data, so we are actually called
166 // because of error here. However, we can get error on out event as well
167 // on some platforms, so we'll simply handle both events in the same way.
168 out_event ();
169}
170
171void zmq::stream_connecter_base_t::create_engine (
172 fd_t fd_, const std::string &local_address_)
173{
174 const endpoint_uri_pair_t endpoint_pair (local_address_, _endpoint,
175 endpoint_type_connect);
176
177 // Create the engine object for this connection.
178 i_engine *engine;
179 if (options.raw_socket)
180 engine = new (std::nothrow) raw_engine_t (fd_, options, endpoint_pair);
181 else
182 engine = new (std::nothrow) zmtp_engine_t (fd_, options, endpoint_pair);
183 alloc_assert (engine);
184
185 // Attach the engine to the corresponding session object.
186 send_attach (_session, engine);
187
188 // Shut the connecter down.
189 terminate ();
190
191 _socket->event_connected (endpoint_pair, fd_);
192}
193
194void zmq::stream_connecter_base_t::timer_event (int id_)
195{
196 zmq_assert (id_ == reconnect_timer_id);
197 _reconnect_timer_started = false;
198 start_connecting ();
199}
200