summaryrefslogtreecommitdiff
path: root/src/tcp_listener.cpp
blob: da476a4f9b929a41932be72fd7118a974ab9ac9e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
/*
    Copyright (c) 2007-2011 iMatix Corporation
    Copyright (c) 2007-2011 Other contributors as noted in the AUTHORS file

    This file is part of 0MQ.

    0MQ is free software; you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    0MQ is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <new>

#include <string.h>

#include "platform.hpp"
#include "tcp_listener.hpp"
#include "stream_engine.hpp"
#include "io_thread.hpp"
#include "session.hpp"
#include "config.hpp"
#include "err.hpp"
#include "ip.hpp"

#ifdef ZMQ_HAVE_WINDOWS
#include "windows.hpp"
#else
#include <unistd.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/tcp.h>
#include <netinet/in.h>
#include <netdb.h>
#include <fcntl.h>
#endif

#ifdef ZMQ_HAVE_OPENVMS
#include <ioctl.h>
#endif

zmq::tcp_listener_t::tcp_listener_t (io_thread_t *io_thread_,
      socket_base_t *socket_, const options_t &options_) :
    own_t (io_thread_, options_),
    io_object_t (io_thread_),
    has_file (false),
    s (retired_fd),
    socket (socket_)
{
}

zmq::tcp_listener_t::~tcp_listener_t ()
{
    if (s != retired_fd)
        close ();
}

void zmq::tcp_listener_t::process_plug ()
{
    //  Start polling for incoming connections.
    handle = add_fd (s);
    set_pollin (handle);
}

void zmq::tcp_listener_t::process_term (int linger_)
{
    rm_fd (handle);
    own_t::process_term (linger_);
}

void zmq::tcp_listener_t::in_event ()
{
    fd_t fd = accept ();

    //  If connection was reset by the peer in the meantime, just ignore it.
    //  TODO: Handle specific errors like ENFILE/EMFILE etc.
    if (fd == retired_fd)
        return;

    tune_tcp_socket (fd);

    //  Create the engine object for this connection.
    stream_engine_t *engine = new (std::nothrow) stream_engine_t (fd, options);
    alloc_assert (engine);

    //  Choose I/O thread to run connecter in. Given that we are already
    //  running in an I/O thread, there must be at least one available.
    io_thread_t *io_thread = choose_io_thread (options.affinity);
    zmq_assert (io_thread);

    //  Create and launch a session object. 
    session_t *session = new (std::nothrow)
        session_t (io_thread, false, socket, options, NULL, NULL);
    alloc_assert (session);
    session->inc_seqnum ();
    launch_child (session);
    send_attach (session, engine, false);
}

void zmq::tcp_listener_t::close ()
{
    zmq_assert (s != retired_fd);
#ifdef ZMQ_HAVE_WINDOWS
    int rc = closesocket (s);
    wsa_assert (rc != SOCKET_ERROR);
#else
    int rc = ::close (s);
    errno_assert (rc == 0);
#endif
    s = retired_fd;
}

int zmq::tcp_listener_t::set_address (const char *addr_)
{
    //  Convert the textual address into address structure.
    int rc = address.resolve (addr_, true, options.ipv4only ? true : false);
    if (rc != 0)
        return -1;

    //  Create a listening socket.
    s = open_socket (address.family (), SOCK_STREAM, IPPROTO_TCP);
#ifdef ZMQ_HAVE_WINDOWS
    if (s == INVALID_SOCKET)
        wsa_error_to_errno ();
#endif

    //  IPv6 address family not supported, try automatic downgrade to IPv4.
    if (address.family () == AF_INET6 && errno == EAFNOSUPPORT &&
          !options.ipv4only) {
        rc = address.resolve (addr_, true, true);
        if (rc != 0)
            return rc;
        s = ::socket (address.family (), SOCK_STREAM, IPPROTO_TCP);
    }

#ifdef ZMQ_HAVE_WINDOWS
    if (s == INVALID_SOCKET) {
        wsa_error_to_errno ();
        return -1;
    }
#else
    if (s == -1)
        return -1;
#endif

    //  On some systems, IPv4 mapping in IPv6 sockets is disabled by default.
    //  Switch it on in such cases.
    if (address.family () == AF_INET6)
        enable_ipv4_mapping (s);

    //  Allow reusing of the address.
    int flag = 1;
#ifdef ZMQ_HAVE_WINDOWS
    rc = setsockopt (s, SOL_SOCKET, SO_EXCLUSIVEADDRUSE,
        (const char*) &flag, sizeof (int));
    wsa_assert (rc != SOCKET_ERROR);
#else
    rc = setsockopt (s, SOL_SOCKET, SO_REUSEADDR, &flag, sizeof (int));
    errno_assert (rc == 0);
#endif

    //  Bind the socket to the network interface and port.
    rc = bind (s, address.addr (), address.addrlen ());
#ifdef ZMQ_HAVE_WINDOWS
    if (rc == SOCKET_ERROR) {
        wsa_error_to_errno ();
        return -1;
    }
#else
    if (rc != 0)
        return -1;
#endif

    //  Listen for incomming connections.
    rc = listen (s, options.backlog);
#ifdef ZMQ_HAVE_WINDOWS
    if (rc == SOCKET_ERROR) {
        wsa_error_to_errno ();
        return -1;
    }
#else
    if (rc != 0)
        return -1;
#endif

    return 0;
}

zmq::fd_t zmq::tcp_listener_t::accept ()
{
    //  Accept one connection and deal with different failure modes.
    zmq_assert (s != retired_fd);
    fd_t sock = ::accept (s, NULL, NULL);
#ifdef ZMQ_HAVE_WINDOWS
    if (sock == INVALID_SOCKET) {
        wsa_assert (WSAGetLastError () == WSAEWOULDBLOCK ||
            WSAGetLastError () == WSAECONNRESET);
        return retired_fd;
    }
#else
    if (sock == -1) {
        errno_assert (errno == EAGAIN || errno == EWOULDBLOCK ||
            errno == EINTR || errno == ECONNABORTED || errno == EPROTO ||
            errno == ENOBUFS);
        return retired_fd;
    }
#endif
    return sock;
}