summaryrefslogtreecommitdiffstats
path: root/lib/Socket.cpp
blob: 50a12bac81e9996da755369bfe5086711a06d51a (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
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
/*
   Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Her Majesty the
   Queen in Right of Canada (Communications Research Center Canada)

   Copyright (C) 2019
   Matthias P. Braendli, matthias.braendli@mpb.li

    http://www.opendigitalradio.org
   */
/*
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

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

#include "Socket.h"

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cerrno>
#include <fcntl.h>
#include <poll.h>

namespace Socket {

using namespace std;

void InetAddress::resolveUdpDestination(const std::string& destination, int port)
{
    char service[NI_MAXSERV];
    snprintf(service, NI_MAXSERV-1, "%d", port);

    struct addrinfo hints;
    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_DGRAM; /* Datagram socket */
    hints.ai_flags = 0;
    hints.ai_protocol = 0;

    struct addrinfo *result, *rp;
    int s = getaddrinfo(destination.c_str(), service, &hints, &result);
    if (s != 0) {
        throw runtime_error(string("getaddrinfo failed: ") + gai_strerror(s));
    }

    for (rp = result; rp != nullptr; rp = rp->ai_next) {
        // Take the first result
        memcpy(&addr, rp->ai_addr, rp->ai_addrlen);
        break;
    }

    freeaddrinfo(result);

    if (rp == nullptr) {
        throw runtime_error("Could not resolve");
    }
}

UDPPacket::UDPPacket() { }

UDPPacket::UDPPacket(size_t initSize) :
    buffer(initSize),
    address()
{ }


UDPSocket::UDPSocket() :
    m_sock(INVALID_SOCKET)
{
    reinit(0, "");
}

UDPSocket::UDPSocket(int port) :
    m_sock(INVALID_SOCKET)
{
    reinit(port, "");
}

UDPSocket::UDPSocket(int port, const std::string& name) :
    m_sock(INVALID_SOCKET)
{
    reinit(port, name);
}


void UDPSocket::setBlocking(bool block)
{
    int res = fcntl(m_sock, F_SETFL, block ? 0 : O_NONBLOCK);
    if (res == -1) {
        throw runtime_error(string("Can't change blocking state of socket: ") + strerror(errno));
    }
}

void UDPSocket::reinit(int port)
{
    return reinit(port, "");
}

void UDPSocket::reinit(int port, const std::string& name)
{
    if (m_sock != INVALID_SOCKET) {
        ::close(m_sock);
    }

    if (port == 0) {
        // No need to bind to a given port, creating the
        // socket is enough
        m_sock = ::socket(AF_INET, SOCK_DGRAM, 0);
        return;
    }

    char service[NI_MAXSERV];
    snprintf(service, NI_MAXSERV-1, "%d", port);

    struct addrinfo hints;
    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_DGRAM; /* Datagram socket */
    hints.ai_flags = AI_PASSIVE;    /* For wildcard IP address */
    hints.ai_protocol = 0;          /* Any protocol */
    hints.ai_canonname = nullptr;
    hints.ai_addr = nullptr;
    hints.ai_next = nullptr;

    struct addrinfo *result, *rp;
    int s = getaddrinfo(name.empty() ? nullptr : name.c_str(),
            port == 0 ? nullptr : service,
            &hints, &result);
    if (s != 0) {
        throw runtime_error(string("getaddrinfo failed: ") + gai_strerror(s));
    }

    /* getaddrinfo() returns a list of address structures.
       Try each address until we successfully bind(2).
       If socket(2) (or bind(2)) fails, we (close the socket
       and) try the next address. */
    for (rp = result; rp != nullptr; rp = rp->ai_next) {
        int sfd = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
        if (sfd == -1) {
            continue;
        }

        if (::bind(sfd, rp->ai_addr, rp->ai_addrlen) == 0) {
            m_sock = sfd;
            break;
        }

        ::close(sfd);
    }

    freeaddrinfo(result);

    if (rp == nullptr) {
        throw runtime_error("Could not bind");
    }
}

void UDPSocket::close()
{
    if (m_sock != INVALID_SOCKET) {
        ::close(m_sock);
    }

    m_sock = INVALID_SOCKET;
}

UDPSocket::~UDPSocket()
{
    if (m_sock != INVALID_SOCKET) {
        ::close(m_sock);
    }
}


UDPPacket UDPSocket::receive(size_t max_size)
{
    UDPPacket packet(max_size);
    socklen_t addrSize;
    addrSize = sizeof(*packet.address.as_sockaddr());
    ssize_t ret = recvfrom(m_sock,
            packet.buffer.data(),
            packet.buffer.size(),
            0,
            packet.address.as_sockaddr(),
            &addrSize);

    if (ret == SOCKET_ERROR) {
        packet.buffer.resize(0);

        // This suppresses the -Wlogical-op warning
#if EAGAIN == EWOULDBLOCK
        if (errno == EAGAIN) {
#else
        if (errno == EAGAIN or errno == EWOULDBLOCK) {
#endif
            return 0;
        }
        throw runtime_error(string("Can't receive data: ") + strerror(errno));
    }

    packet.buffer.resize(ret);
    return packet;
}

void UDPSocket::send(UDPPacket& packet)
{
    const int ret = sendto(m_sock, packet.buffer.data(), packet.buffer.size(), 0,
            packet.address.as_sockaddr(), sizeof(*packet.address.as_sockaddr()));
    if (ret == SOCKET_ERROR && errno != ECONNREFUSED) {
        throw runtime_error(string("Can't send UDP packet: ") + strerror(errno));
    }
}


void UDPSocket::send(const std::vector<uint8_t>& data, InetAddress destination)
{
    const int ret = sendto(m_sock, data.data(), data.size(), 0,
            destination.as_sockaddr(), sizeof(*destination.as_sockaddr()));
    if (ret == SOCKET_ERROR && errno != ECONNREFUSED) {
        throw runtime_error(string("Can't send UDP packet: ") + strerror(errno));
    }
}

void UDPSocket::joinGroup(const char* groupname, const char* if_addr)
{
    ip_mreqn group;
    if ((group.imr_multiaddr.s_addr = inet_addr(groupname)) == INADDR_NONE) {
        throw runtime_error("Cannot convert multicast group name");
    }
    if (!IN_MULTICAST(ntohl(group.imr_multiaddr.s_addr))) {
        throw runtime_error("Group name is not a multicast address");
    }

    if (if_addr) {
        group.imr_address.s_addr = inet_addr(if_addr);
    }
    else {
        group.imr_address.s_addr = htons(INADDR_ANY);
    }
    group.imr_ifindex = 0;
    if (setsockopt(m_sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &group, sizeof(group))
            == SOCKET_ERROR) {
        throw runtime_error(string("Can't join multicast group") + strerror(errno));
    }
}

void UDPSocket::setMulticastSource(const char* source_addr)
{
    struct in_addr addr;
    if (inet_aton(source_addr, &addr) == 0) {
        throw runtime_error(string("Can't parse source address") + strerror(errno));
    }

    if (setsockopt(m_sock, IPPROTO_IP, IP_MULTICAST_IF, &addr, sizeof(addr))
            == SOCKET_ERROR) {
        throw runtime_error(string("Can't set source address") + strerror(errno));
    }
}

void UDPSocket::setMulticastTTL(int ttl)
{
    if (setsockopt(m_sock, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl))
            == SOCKET_ERROR) {
        throw runtime_error(string("Can't set multicast ttl") + strerror(errno));
    }
}

UDPReceiver::UDPReceiver() { }

UDPReceiver::~UDPReceiver() {
    m_stop = true;
    m_sock.close();
    if (m_thread.joinable()) {
        m_thread.join();
    }
}

void UDPReceiver::start(int port, const string& bindto, const string& mcastaddr, size_t max_packets_queued) {
    m_port = port;
    m_bindto = bindto;
    m_mcastaddr = mcastaddr;
    m_max_packets_queued = max_packets_queued;
    m_thread = std::thread(&UDPReceiver::m_run, this);
}

std::vector<uint8_t> UDPReceiver::get_packet_buffer()
{
    if (m_stop) {
        throw runtime_error("UDP Receiver not running");
    }

    UDPPacket p;
    m_packets.wait_and_pop(p);

    return p.buffer;
}

void UDPReceiver::m_run()
{
    // Ensure that stop is set to true in case of exception or return
    struct SetStopOnDestruct {
        SetStopOnDestruct(atomic<bool>& stop) : m_stop(stop) {}
        ~SetStopOnDestruct() { m_stop = true; }
        private: atomic<bool>& m_stop;
    } autoSetStop(m_stop);

    if (IN_MULTICAST(ntohl(inet_addr(m_mcastaddr.c_str())))) {
        m_sock.reinit(m_port, m_mcastaddr);
        m_sock.setMulticastSource(m_bindto.c_str());
        m_sock.joinGroup(m_mcastaddr.c_str(), m_bindto.c_str());
    }
    else {
        m_sock.reinit(m_port, m_bindto);
    }

    while (not m_stop) {
        constexpr size_t packsize = 8192;
        try {
            auto packet = m_sock.receive(packsize);
            if (packet.buffer.size() == packsize) {
                // TODO replace fprintf
                fprintf(stderr, "Warning, possible UDP truncation\n");
            }

            // If this blocks, the UDP socket will lose incoming packets
            m_packets.push_wait_if_full(packet, m_max_packets_queued);
        }
        catch (const std::runtime_error& e) {
            // TODO replace fprintf
            // TODO handle intr
            fprintf(stderr, "Socket error: %s\n", e.what());
            m_stop = true;
        }
    }
}


TCPSocket::TCPSocket()
{
}

TCPSocket::~TCPSocket()
{
    if (m_sock != -1) {
        ::close(m_sock);
    }
}

TCPSocket::TCPSocket(TCPSocket&& other) :
    m_sock(other.m_sock),
    m_remote_address(move(other.m_remote_address))
{
    if (other.m_sock != -1) {
        other.m_sock = -1;
    }
}

TCPSocket& TCPSocket::operator=(TCPSocket&& other)
{
    swap(m_remote_address, other.m_remote_address);

    m_sock = other.m_sock;
    if (other.m_sock != -1) {
        other.m_sock = -1;
    }

    return *this;
}

bool TCPSocket::valid() const
{
    return m_sock != -1;
}

void TCPSocket::connect(const std::string& hostname, int port, bool nonblock)
{
    if (m_sock != INVALID_SOCKET) {
        throw std::logic_error("You may only connect an invalid TCPSocket");
    }

    char service[NI_MAXSERV];
    snprintf(service, NI_MAXSERV-1, "%d", port);

    /* Obtain address(es) matching host/port */
    struct addrinfo hints;
    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_flags = 0;
    hints.ai_protocol = 0;

    struct addrinfo *result, *rp;
    int s = getaddrinfo(hostname.c_str(), service, &hints, &result);
    if (s != 0) {
        throw runtime_error(string("getaddrinfo failed: ") + gai_strerror(s));
    }

    /* getaddrinfo() returns a list of address structures.
       Try each address until we successfully connect(2).
       If socket(2) (or connect(2)) fails, we (close the socket
       and) try the next address. */

    for (rp = result; rp != nullptr; rp = rp->ai_next) {
        int sfd = ::socket(rp->ai_family, rp->ai_socktype,
                rp->ai_protocol);
        if (sfd == -1)
            continue;

        if (nonblock) {
            int flags = fcntl(sfd, F_GETFL);
            if (flags == -1) {
                std::string errstr(strerror(errno));
                throw std::runtime_error("TCP: Could not get socket flags: " + errstr);
            }

            if (fcntl(sfd, F_SETFL, flags | O_NONBLOCK) == -1) {
                std::string errstr(strerror(errno));
                throw std::runtime_error("TCP: Could not set O_NONBLOCK: " + errstr);
            }
        }

        int ret = ::connect(sfd, rp->ai_addr, rp->ai_addrlen);
        if (ret != -1 or (ret == -1 and errno == EINPROGRESS)) {
            m_sock = sfd;
            break;
        }

        ::close(sfd);
    }

    if (m_sock != INVALID_SOCKET) {
#if defined(HAVE_SO_NOSIGPIPE)
        int val = 1;
        if (setsockopt(m_sock, SOL_SOCKET, SO_NOSIGPIPE, &val, sizeof(val))
                == SOCKET_ERROR) {
            throw std::runtime_error("Can't set SO_NOSIGPIPE");
        }
#endif
    }

    freeaddrinfo(result);           /* No longer needed */

    if (rp == nullptr) {
        throw runtime_error("Could not connect");
    }

}

void TCPSocket::listen(int port, const string& name)
{
    if (m_sock != INVALID_SOCKET) {
        throw std::logic_error("You may only listen with an invalid TCPSocket");
    }

    char service[NI_MAXSERV];
    snprintf(service, NI_MAXSERV-1, "%d", port);

    struct addrinfo hints;
    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_flags = AI_PASSIVE;    /* For wildcard IP address */
    hints.ai_protocol = 0;
    hints.ai_canonname = nullptr;
    hints.ai_addr = nullptr;
    hints.ai_next = nullptr;

    struct addrinfo *result, *rp;
    int s = getaddrinfo(name.empty() ? nullptr : name.c_str(), service, &hints, &result);
    if (s != 0) {
        throw runtime_error(string("getaddrinfo failed: ") + gai_strerror(s));
    }

    /* getaddrinfo() returns a list of address structures.
       Try each address until we successfully bind(2).
       If socket(2) (or bind(2)) fails, we (close the socket
       and) try the next address. */
    for (rp = result; rp != nullptr; rp = rp->ai_next) {
        int sfd = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
        if (sfd == -1) {
            continue;
        }

        int reuse_setting = 1;
        if (setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse_setting, sizeof(reuse_setting)) == -1) {
            throw runtime_error("Can't reuse address");
        }

        if (::bind(sfd, rp->ai_addr, rp->ai_addrlen) == 0) {
            m_sock = sfd;
            break;
        }

        ::close(sfd);
    }

    freeaddrinfo(result);

    if (m_sock != INVALID_SOCKET) {
#if defined(HAVE_SO_NOSIGPIPE)
        int val = 1;
        if (setsockopt(m_sock, SOL_SOCKET, SO_NOSIGPIPE,
                    &val, sizeof(val)) < 0) {
            throw std::runtime_error("Can't set SO_NOSIGPIPE");
        }
#endif

        int ret = ::listen(m_sock, 0);
        if (ret == -1) {
            throw std::runtime_error(string("Could not listen: ") + strerror(errno));
        }
    }

    if (rp == nullptr) {
        throw runtime_error("Could not bind");
    }
}

void TCPSocket::close()
{
    ::close(m_sock);
    m_sock = -1;
}

TCPSocket TCPSocket::accept(int timeout_ms)
{
    if (timeout_ms == 0) {
        InetAddress remote_addr;
        socklen_t client_len = sizeof(remote_addr.addr);
        int sockfd = ::accept(m_sock, remote_addr.as_sockaddr(), &client_len);
        TCPSocket s(sockfd, remote_addr);
        return s;
    }
    else {
        struct pollfd fds[1];
        fds[0].fd = m_sock;
        fds[0].events = POLLIN;

        int retval = poll(fds, 1, timeout_ms);

        if (retval == -1) {
            std::string errstr(strerror(errno));
            throw std::runtime_error("TCP Socket accept error: " + errstr);
        }
        else if (retval > 0) {
            InetAddress remote_addr;
            socklen_t client_len = sizeof(remote_addr.addr);
            int sockfd = ::accept(m_sock, remote_addr.as_sockaddr(), &client_len);
            TCPSocket s(sockfd, remote_addr);
            return s;
        }
        else {
            TCPSocket s(-1);
            return s;
        }
    }
}

ssize_t TCPSocket::sendall(const void *buffer, size_t buflen)
{
    uint8_t *buf = (uint8_t*)buffer;
    while (buflen > 0) {
        /* On Linux, the MSG_NOSIGNAL flag ensures that the process
         * would not receive a SIGPIPE and die.
         * Other systems have SO_NOSIGPIPE set on the socket for the
         * same effect. */
#if defined(HAVE_MSG_NOSIGNAL)
        const int flags = MSG_NOSIGNAL;
#else
        const int flags = 0;
#endif
        ssize_t sent = ::send(m_sock, buf, buflen, flags);
        if (sent < 0) {
            return -1;
        }
        else {
            buf += sent;
            buflen -= sent;
        }
    }
    return buflen;
}

ssize_t TCPSocket::send(const void* data, size_t size, int timeout_ms)
{
    if (timeout_ms) {
        struct pollfd fds[1];
        fds[0].fd = m_sock;
        fds[0].events = POLLOUT;

        const int retval = poll(fds, 1, timeout_ms);

        if (retval == -1) {
            throw std::runtime_error(string("TCP Socket send error on poll(): ") + strerror(errno));
        }
        else if (retval == 0) {
            // Timed out
            return 0;
        }
    }

    /* On Linux, the MSG_NOSIGNAL flag ensures that the process would not
     * receive a SIGPIPE and die.
     * Other systems have SO_NOSIGPIPE set on the socket for the same effect. */
#if defined(HAVE_MSG_NOSIGNAL)
    const int flags = MSG_NOSIGNAL;
#else
    const int flags = 0;
#endif
    const ssize_t ret = ::send(m_sock, (const char*)data, size, flags);

    if (ret == SOCKET_ERROR) {
            throw std::runtime_error(string("TCP Socket send error: ") + strerror(errno));
    }
    return ret;
}

ssize_t TCPSocket::recv(void *buffer, size_t length, int flags)
{
    ssize_t ret = ::recv(m_sock, buffer, length, flags);
    if (ret == -1) {
        std::string errstr(strerror(errno));
        throw std::runtime_error("TCP receive error: " + errstr);
    }
    return ret;
}

ssize_t TCPSocket::recv(void *buffer, size_t length, int flags, int timeout_ms)
{
    struct pollfd fds[1];
    fds[0].fd = m_sock;
    fds[0].events = POLLIN;

    int retval = poll(fds, 1, timeout_ms);

    if (retval == -1 and errno == EINTR) {
        throw Interrupted();
    }
    else if (retval == -1) {
        std::string errstr(strerror(errno));
        throw std::runtime_error("TCP receive with poll() error: " + errstr);
    }
    else if (retval > 0 and (fds[0].revents | POLLIN)) {
        ssize_t ret = ::recv(m_sock, buffer, length, flags);
        if (ret == -1) {
            if (errno == ECONNREFUSED) {
                return 0;
            }
            std::string errstr(strerror(errno));
            throw std::runtime_error("TCP receive after poll() error: " + errstr);
        }
        return ret;
    }
    else {
        throw Timeout();
    }
}

TCPSocket::TCPSocket(int sockfd) :
    m_sock(sockfd),
    m_remote_address()
{ }

TCPSocket::TCPSocket(int sockfd, InetAddress remote_address) :
    m_sock(sockfd),
    m_remote_address(remote_address)
{ }

void TCPClient::connect(const std::string& hostname, int port)
{
    m_hostname = hostname;
    m_port = port;
    reconnect();
}

ssize_t TCPClient::recv(void *buffer, size_t length, int flags, int timeout_ms)
{
    try {
        ssize_t ret = m_sock.recv(buffer, length, flags, timeout_ms);

        if (ret == 0) {
            m_sock.close();
            reconnect();
        }

        return ret;
    }
    catch (const TCPSocket::Interrupted&) {
        return -1;
    }
    catch (const TCPSocket::Timeout&) {
        return 0;
    }

    return 0;
}

void TCPClient::reconnect()
{
    TCPSocket newsock;
    m_sock = std::move(newsock);
    m_sock.connect(m_hostname, m_port, true);
}

TCPConnection::TCPConnection(TCPSocket&& sock) :
            queue(),
            m_running(true),
            m_sender_thread(),
            m_sock(move(sock))
{
#if MISSING_OWN_ADDR
    auto own_addr = m_sock.getOwnAddress();
    auto addr = m_sock.getRemoteAddress();
    etiLog.level(debug) << "New TCP Connection on port " <<
        own_addr.getPort() << " from " <<
        addr.getHostAddress() << ":" << addr.getPort();
#endif
    m_sender_thread = std::thread(&TCPConnection::process, this);
}

TCPConnection::~TCPConnection()
{
    m_running = false;
    vector<uint8_t> termination_marker;
    queue.push(termination_marker);
    m_sender_thread.join();
}

void TCPConnection::process()
{
    while (m_running) {
        vector<uint8_t> data;
        queue.wait_and_pop(data);

        if (data.empty()) {
            // empty vector is the termination marker
            m_running = false;
            break;
        }

        try {
            ssize_t remaining = data.size();
            const uint8_t *buf = reinterpret_cast<const uint8_t*>(data.data());
            const int timeout_ms = 10; // Less than one ETI frame

            while (m_running and remaining > 0) {
                const ssize_t sent = m_sock.send(buf, remaining, timeout_ms);
                if (sent < 0 or sent > remaining) {
                    throw std::logic_error("Invalid TCPSocket::send() return value");
                }
                remaining -= sent;
                buf += sent;
            }
        }
        catch (const std::runtime_error& e) {
            m_running = false;
        }
    }

#if MISSING_OWN_ADDR
    auto own_addr = m_sock.getOwnAddress();
    auto addr = m_sock.getRemoteAddress();
    etiLog.level(debug) << "Dropping TCP Connection on port " <<
        own_addr.getPort() << " from " <<
        addr.getHostAddress() << ":" << addr.getPort();
#endif
}


TCPDataDispatcher::TCPDataDispatcher(size_t max_queue_size) :
    m_max_queue_size(max_queue_size)
{
}

TCPDataDispatcher::~TCPDataDispatcher()
{
    m_running = false;
    m_connections.clear();
    m_listener_socket.close();
    if (m_listener_thread.joinable()) {
        m_listener_thread.join();
    }
}

void TCPDataDispatcher::start(int port, const string& address)
{
    m_listener_socket.listen(port, address);

    m_running = true;
    m_listener_thread = std::thread(&TCPDataDispatcher::process, this);
}

void TCPDataDispatcher::write(const vector<uint8_t>& data)
{
    if (not m_running) {
        throw runtime_error(m_exception_data);
    }

    for (auto& connection : m_connections) {
        connection.queue.push(data);
    }

    m_connections.remove_if(
            [&](const TCPConnection& conn){ return conn.queue.size() > m_max_queue_size; });
}

void TCPDataDispatcher::process()
{
    try {
        const int timeout_ms = 1000;

        while (m_running) {
            // Add a new TCPConnection to the list, constructing it from the client socket
            auto sock = m_listener_socket.accept(timeout_ms);
            if (sock.valid()) {
                m_connections.emplace(m_connections.begin(), move(sock));
            }
        }
    }
    catch (const std::runtime_error& e) {
        m_exception_data = string("TCPDataDispatcher error: ") + e.what();
        m_running = false;
    }
}

TCPReceiveServer::TCPReceiveServer(size_t blocksize) :
    m_blocksize(blocksize)
{
}

void TCPReceiveServer::start(int listen_port, const std::string& address)
{
    m_listener_socket.listen(listen_port, address);

    m_running = true;
    m_listener_thread = std::thread(&TCPReceiveServer::process, this);
}

TCPReceiveServer::~TCPReceiveServer()
{
    m_running = false;
    if (m_listener_thread.joinable()) {
        m_listener_thread.join();
    }
}

vector<uint8_t> TCPReceiveServer::receive()
{
    vector<uint8_t> buffer;
    m_queue.try_pop(buffer);

    // we can ignore try_pop()'s return value, because
    // if it is unsuccessful the buffer is not touched.
    return buffer;
}

void TCPReceiveServer::process()
{
    constexpr int timeout_ms = 1000;
    constexpr int disconnect_timeout_ms = 10000;
    constexpr int max_num_timeouts = disconnect_timeout_ms / timeout_ms;

    while (m_running) {
        auto sock = m_listener_socket.accept(timeout_ms);

        int num_timeouts = 0;

        while (m_running and sock.valid()) {
            try {
                vector<uint8_t> buf(m_blocksize);
                ssize_t r = sock.recv(buf.data(), buf.size(), 0, timeout_ms);
                if (r < 0) {
                    throw logic_error("Invalid recv return value");
                }
                else if (r == 0) {
                    sock.close();
                    break;
                }
                else {
                    buf.resize(r);
                    m_queue.push(move(buf));
                }
            }
            catch (const TCPSocket::Interrupted&) {
                break;
            }
            catch (const TCPSocket::Timeout&) {
                num_timeouts++;
            }

            if (num_timeouts > max_num_timeouts) {
                sock.close();
            }
        }
    }
}

}