ipv6.c

这不是一个完整的工程

    /* Open a SOCK_DGRAM (UDP) socket, in the AF_INET6 domain, automatic (0)
     * protocol */
    if( (i_handle = socket( AF_INET6, SOCK_DGRAM, 0 )) == -1 )
    {
        msg_Warn( p_this, "cannot create socket (%s)", strerror(errno) );
        return( -1 );
    }

    /* We may want to reuse an already used socket */
    i_opt = 1;
    if( setsockopt( i_handle, SOL_SOCKET, SO_REUSEADDR,
                    (void *) &i_opt, sizeof( i_opt ) ) == -1 )
    {
        msg_Warn( p_this, "cannot configure socket (SO_REUSEADDR: %s)",
                         strerror(errno) );
        close( i_handle );
        return( -1 );
    }

    /* Increase the receive buffer size to 1/2MB (8Mb/s during 1/2s) to avoid
     * packet loss caused by scheduling problems */
    i_opt = 0x80000;
    if( setsockopt( i_handle, SOL_SOCKET, SO_RCVBUF,
                    (void *) &i_opt, sizeof( i_opt ) ) == -1 )
    {
        msg_Warn( p_this, "cannot configure socket (SO_RCVBUF: %s)",
                          strerror(errno) );
    }

    /* Check if we really got what we have asked for, because Linux, etc.
     * will silently limit the max buffer size to net.core.rmem_max which
     * is typically only 65535 bytes */
    i_opt = 0;
    i_opt_size = sizeof( i_opt );
    if( getsockopt( i_handle, SOL_SOCKET, SO_RCVBUF,
                    (void*) &i_opt, &i_opt_size ) == -1 )
    {
        msg_Warn( p_this, "cannot query socket (SO_RCVBUF: %s)",
                          strerror(errno) );
    }
    else if( i_opt < 0x80000 )
    {
        msg_Warn( p_this, "socket buffer size is 0x%x instead of 0x%x",
                          i_opt, 0x80000 );
    }

    /* Build the local socket */
    if ( BuildAddr( p_this, &sock, psz_bind_addr, i_bind_port ) == -1 )        
    {
        close( i_handle );
        return( -1 );
    }

#if defined(WIN32)
    /* Under Win32 and for multicasting, we bind to IN6ADDR_ANY */
    if( IN6_IS_ADDR_MULTICAST(&sock.sin6_addr) )
    {
        struct sockaddr_in6 sockany = sock;
        sockany.sin6_addr = in6addr_any;
        sockany.sin6_scope_id = 0;

        /* Bind it */
        if( bind( i_handle, (struct sockaddr *)&sockany, sizeof( sock ) ) < 0 )
        {
            msg_Warn( p_this, "cannot bind socket (%s)", strerror(errno) );
            close( i_handle );
            return( -1 );
        }
    } else
#endif
    /* Bind it */
    if( bind( i_handle, (struct sockaddr *)&sock, sizeof( sock ) ) < 0 )
    {
        msg_Warn( p_this, "cannot bind socket (%s)", strerror(errno) );
        close( i_handle );
        return( -1 );
    }

    /* Allow broadcast reception if we bound on in6addr_any */
    if( !*psz_bind_addr )
    {
        i_opt = 1;
        if( setsockopt( i_handle, SOL_SOCKET, SO_BROADCAST,
                        (void*) &i_opt, sizeof( i_opt ) ) == -1 )
        {
            msg_Warn( p_this, "ipv6 warning: cannot configure socket "
                              "(SO_BROADCAST: %s)", strerror(errno) );
        }
    }

    /* Join the multicast group if the socket is a multicast address */
#if defined( WIN32 ) || defined( HAVE_IF_NAMETOINDEX )
    if( IN6_IS_ADDR_MULTICAST(&sock.sin6_addr) )
    {
        struct ipv6_mreq     imr;
        int                  res;

        imr.ipv6mr_interface = sock.sin6_scope_id;
        imr.ipv6mr_multiaddr = sock.sin6_addr;
        res = setsockopt(i_handle, IPPROTO_IPV6, IPV6_JOIN_GROUP, (void*) &imr,
#if defined(WIN32)
                         sizeof(imr) + 4); /* Doesn't work without this */
#else
                         sizeof(imr));
#endif

        if( res == -1 )
        {
            msg_Err( p_this, "cannot join multicast group" );
        } 
    }
#else
    msg_Warn( p_this, "Multicast IPv6 is not supported on your OS" );
#endif


    if( *psz_server_addr )
    {
        int ttl = p_socket->i_ttl;
        if( ttl < 1 )
        {
            ttl = config_GetInt( p_this, "ttl" );
        }
        if( ttl < 1 ) ttl = 1;

        /* Build socket for remote connection */
        if ( BuildAddr( p_this, &sock, psz_server_addr, i_server_port ) == -1 )
        {
            msg_Warn( p_this, "cannot build remote address" );
            close( i_handle );
            return( -1 );
        }

        /* Connect the socket */
        if( connect( i_handle, (struct sockaddr *) &sock,
                     sizeof( sock ) ) == (-1) )
        {
            msg_Warn( p_this, "cannot connect socket (%s)", strerror(errno) );
            close( i_handle );
            return( -1 );
        }

        /* Set the time-to-live */
        if( ttl > 1 )
        {
#if defined( WIN32 ) || defined( HAVE_IF_NAMETOINDEX )
            if( IN6_IS_ADDR_MULTICAST(&sock.sin6_addr) )
            {
                if( setsockopt( i_handle, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
                                (void *)&ttl, sizeof( ttl ) ) < 0 )
                {
#ifdef HAVE_ERRNO_H
                    msg_Err( p_this, "failed to set multicast ttl (%s)",
                             strerror(errno) );
#else
                    msg_Err( p_this, "failed to set multicast ttl" );
#endif
                }
            }
            else
#endif
            {
                if( setsockopt( i_handle, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
                                (void *)&ttl, sizeof( ttl ) ) < 0 )
                {
#ifdef HAVE_ERRNO_H
                    msg_Err( p_this, "failed to set unicast ttl (%s)",
                              strerror(errno) );
#else
                    msg_Err( p_this, "failed to set unicast ttl" );
#endif
                }
            }
        }
    }

    p_socket->i_handle = i_handle;
    p_socket->i_mtu = config_GetInt( p_this, "mtu" );

    return( 0 );
}

/*****************************************************************************
 * OpenTCP: open a TCP socket
 *****************************************************************************
 * psz_server_addr, i_server_port : address and port used for the connect()
 *   system call. If i_server_port == 0, 80 is used.
 * Other parameters are ignored.
 * This function returns -1 in case of error.
 *****************************************************************************/
static int OpenTCP( vlc_object_t * p_this, network_socket_t * p_socket )
{
    char * psz_server_addr = p_socket->psz_server_addr;
    int i_server_port = p_socket->i_server_port;

    int i_handle;
    struct sockaddr_in6 sock;

    if( i_server_port == 0 )
    {
        i_server_port = 80;
    }

    /* Open a SOCK_STREAM (TCP) socket, in the AF_INET6 domain, automatic (0)
     * protocol */
    if( (i_handle = socket( AF_INET6, SOCK_STREAM, 0 )) == -1 )
    {
        msg_Warn( p_this, "cannot create socket (%s)", strerror(errno) );
        return( -1 );
    }

    /* Build remote address */
    if ( BuildAddr( p_this, &sock, psz_server_addr, i_server_port ) == -1 )
    {
        close( i_handle );
        return( -1 );
    }

    /* Connect the socket */
    if( connect( i_handle, (struct sockaddr *) &sock,
                 sizeof( sock ) ) == (-1) )
    {
        msg_Warn( p_this, "cannot connect socket (%s)", strerror(errno) );
        close( i_handle );
        return( -1 );
    }

    p_socket->i_handle = i_handle;
    p_socket->i_mtu = 0; /* There is no MTU notion in TCP */

    return( 0 );
}

/*****************************************************************************
 * Open: wrapper around OpenUDP and OpenTCP
 *****************************************************************************/
static int Open( vlc_object_t * p_this )
{
    network_socket_t * p_socket = p_this->p_private;

    if( p_socket->i_type == NETWORK_UDP )
    {
        return OpenUDP( p_this, p_socket );
    }
    else
    {
        return OpenTCP( p_this, p_socket );
    }
}