summaryrefslogtreecommitdiff
path: root/src/multicast.cc
blob: 35b0212a10db90bc784adeb244d1fdadef11d9cc (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
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            multicast.cc
 *
 *  Mon Sep 26 12:25:22 CEST 2005
 *  Copyright  2005 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of MIaV.
 *
 *  MIaV 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 2 of the License, or
 *  (at your option) any later version.
 *
 *  MIaV 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 MIaV; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "multicast.h"

#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <sys/param.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>

#include <hugin.hpp>

#include "multicast_configuration.h"
#include "miav_config.h"

Multicast::Multicast(mcastconf_t &mcclientconf)
{
  udp_buffer = NULL;
  
  multicast_audio = mcclientconf.with_audio;
    
  // Open connection socket
  if(!UDPOpen(mcclientconf.addr.c_str(), mcclientconf.port)) 
    ERR(multicast, "Error creating socket %s:%d", 
        mcclientconf.addr.c_str(),
        mcclientconf.port);

  int mtu = config->readInt("udp_packet_size");

  // Create buffer with the size of MTU
  //  socklen_t mtu_sz;
  //  if(getsockopt(sock, SOL_IP, IP_MTU, &mtu, &mtu_sz) != -1) {

  udp_buffer_size = mtu - 28;
  if(udp_buffer_size < 1) udp_buffer_size = 1;
  udp_buffer = new char[udp_buffer_size];
  udp_buffer_pointer = udp_buffer;
  DEBUG(multicast, "UDP packet buffer size %db", udp_buffer_size);

  //} else {
  //  ERR(multicast, "Error getting MTU size from socket: %s", strerror(errno));
  //  return;
  //}
}

Multicast::~Multicast()
{
  if(udp_buffer) delete udp_buffer;
}

int Multicast::Write(void* buf, int size)
{
  if(!udp_buffer) return 0; // no buffer to write in... better break out!

  //  DEBUG(multicast, "To send: %d", size);

  char *p = (char*)buf;
  int left = udp_buffer_size - (udp_buffer_pointer - udp_buffer);
 
  while(size) {
    int to_copy = size > left ? left : size;
    
    memcpy(udp_buffer_pointer, p, to_copy);
  
    left-=to_copy;
    udp_buffer_pointer += to_copy;

    p+=to_copy;
    size-=to_copy;

    //    DEBUG(multicast, "Copied %d - %d to go", to_copy, size);

    if(left == 0) {
      //      DEBUG(multicast, "Sending full packet");
      if(write(sock, udp_buffer, udp_buffer_size) != udp_buffer_size) {
        ERR(multicast, "Could not write entire buffer to socket.");
      }
      left = udp_buffer_size;
      udp_buffer_pointer = udp_buffer;
    }
  }
  return size;
}

bool Multicast::is_address_multicast(unsigned long address)
{
  if((address & 255) >= 224 && (address & 255) <= 239) {
    INFO(multicast, "Address is multicast.");
    return true;
  }
  INFO(multicast, "Address is NOT multicast.");
  return false;
}

/*
 * open UDP socket
 */
bool Multicast::UDPOpen(const char *address, int port)
{
  int enable = 1L;
  struct sockaddr_in stAddr;
  struct sockaddr_in stLclAddr;
  struct hostent * host;
  //  int sock;
  
  stAddr.sin_family = AF_INET;
  stAddr.sin_port = htons(port);
  if((host = gethostbyname(address)) == NULL) return false;
  stAddr.sin_addr = *((struct in_addr *) host->h_addr_list[0]);

  // Create a UDP socket
  if((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
        return false;

  // Allow multiple instance of the client to share the same address and port
  if(setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *) &enable, sizeof(unsigned long int)) < 0) 
    return false;

  // If the address is multicast, register to the multicast group
  if(is_address_multicast(stAddr.sin_addr.s_addr)) {
    struct ip_mreq stMreq;
    
    // Bind the socket to port
    stLclAddr.sin_family      = AF_INET;
    stLclAddr.sin_addr.s_addr = htonl(INADDR_ANY);
    stLclAddr.sin_port        = stAddr.sin_port;
    if(bind(sock, (struct sockaddr*) & stLclAddr, sizeof(stLclAddr)) < 0) return false;

    // Register to a multicast address
    stMreq.imr_multiaddr.s_addr = stAddr.sin_addr.s_addr;
    stMreq.imr_interface.s_addr = INADDR_ANY;
    if(setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *) & stMreq, sizeof(stMreq)) < 0) 
      return false;
  } else {
    // Bind the socket to port
    stLclAddr.sin_family      = AF_INET;
    stLclAddr.sin_addr.s_addr = htonl(INADDR_ANY);
    stLclAddr.sin_port        = htons(0);
    if(bind(sock, (struct sockaddr*) & stLclAddr, sizeof(stLclAddr)) < 0)
        return false;
  }

  connect(sock, (struct sockaddr*) & stAddr, sizeof(stAddr));

  return true;
}