ipv4.c

VLC媒体播放程序

    if( IN_MULTICAST( ntohl(sock.sin_addr.s_addr) ) )
    {
        /* Determine interface to be used for multicast */
        char * psz_if_addr = config_GetPsz( p_this, "iface-addr" );

        /* If we have a source address, we use IP_ADD_SOURCE_MEMBERSHIP
           so that IGMPv3 aware OSes running on IGMPv3 aware networks
           will do an IGMPv3 query on the network */
        if( *psz_server_addr )
        {
            struct ip_mreq_source imr;

            imr.imr_multiaddr.s_addr = sock.sin_addr.s_addr;
            imr.imr_sourceaddr.s_addr = inet_addr(psz_server_addr);

            if( psz_if_addr != NULL && *psz_if_addr
                && inet_addr(psz_if_addr) != INADDR_NONE )
            {
                imr.imr_interface.s_addr = inet_addr(psz_if_addr);
            }
            else
            {
                imr.imr_interface.s_addr = INADDR_ANY;
            }
            if( psz_if_addr != NULL ) free( psz_if_addr );

            msg_Dbg( p_this, "IP_ADD_SOURCE_MEMBERSHIP multicast request" );
            /* Join Multicast group with source filter */
            if( setsockopt( i_handle, IPPROTO_IP, IP_ADD_SOURCE_MEMBERSHIP,
                         (char*)&imr,
                         sizeof(struct ip_mreq_source) ) == -1 )
            {
#ifdef HAVE_ERRNO_H
                msg_Err( p_this, "failed to join IP multicast group (%s)",
                                  strerror(errno) );
                msg_Err( p_this, "are you sure your OS supports IGMPv3?" );
#else
                msg_Err( p_this, "failed to join IP multicast group" );
                msg_Err( p_this, "are you sure your OS supports IGMPv3?" );
#endif
                close( i_handle );
                return( -1 );
            }
         }
         /* If there is no source address, we use IP_ADD_MEMBERSHIP */
         else
         {
             struct ip_mreq imr;

             imr.imr_multiaddr.s_addr = sock.sin_addr.s_addr;
             if( psz_if_addr != NULL && *psz_if_addr
                && inet_addr(psz_if_addr) != INADDR_NONE )
            {
                imr.imr_interface.s_addr = inet_addr(psz_if_addr);
            }
            else
            {
                imr.imr_interface.s_addr = INADDR_ANY;
            }
            if( psz_if_addr != NULL ) free( psz_if_addr );

            msg_Dbg( p_this, "IP_ADD_MEMBERSHIP multicast request" );
            /* Join Multicast group without source filter */
            if( setsockopt( i_handle, IPPROTO_IP, IP_ADD_MEMBERSHIP,
                            (char*)&imr, sizeof(struct ip_mreq) ) == -1 )
            {
#ifdef HAVE_ERRNO_H
                msg_Err( p_this, "failed to join IP multicast group (%s)",
                                  strerror(errno) );
#else
                msg_Err( p_this, "failed to join IP multicast group" );
#endif
                close( i_handle );
                return( -1 );
            }
         }
    }
#endif

    if( *psz_server_addr )
    {
        /* Build socket for remote connection */
        if ( BuildAddr( &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) )
        {
#ifdef HAVE_ERRNO_H
            msg_Warn( p_this, "cannot connect socket (%s)", strerror(errno) );
#else
            msg_Warn( p_this, "cannot connect socket" );
#endif
            close( i_handle );
            return( -1 );
        }

#if !defined( UNDER_CE ) && !defined( SYS_BEOS )
        if( IN_MULTICAST( ntohl(inet_addr(psz_server_addr) ) ) )
        {
            /* set the time-to-live */
            int ttl = p_socket->i_ttl;
            if( ttl < 1 )
            {
                ttl = config_GetInt( p_this, "ttl" );
            }
            if( ttl < 1 ) ttl = 1;

            if( setsockopt( i_handle, IPPROTO_IP, IP_MULTICAST_TTL,
                            (void *) &ttl, sizeof( ttl ) ) < 0 )
            {
#ifdef HAVE_ERRNO_H
                msg_Err( p_this, "failed to set ttl (%s)", strerror(errno) );
#else
                msg_Err( p_this, "failed to set ttl" );
#endif
                close( i_handle );
                return( -1 );
            }
        }
#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_in sock;

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

    /* Open a SOCK_STREAM (TCP) socket, in the AF_INET domain, automatic (0)
     * protocol */
    if( (i_handle = socket( AF_INET, SOCK_STREAM, 0 )) == -1 )
    {
#ifdef HAVE_ERRNO_H
        msg_Warn( p_this, "cannot create socket (%s)", strerror(errno) );
#else
        msg_Warn( p_this, "cannot create socket" );
#endif
        goto error;
    }

    /* Build remote address */
    if ( BuildAddr( &sock, psz_server_addr, i_server_port ) == -1 )
    {
        msg_Dbg( p_this, "could not build local address" );
        goto error;
    }

    /* Set to non-blocking */
#if defined( WIN32 ) || defined( UNDER_CE )
    {
        unsigned long i_dummy = 1;
        if( ioctlsocket( i_handle, FIONBIO, &i_dummy ) != 0 )
        {
            msg_Err( p_this, "cannot set socket to non-blocking mode" );
        }
    }
#elif defined( HAVE_ERRNO_H )
    {
        int i_flags;
        if( ( i_flags = fcntl( i_handle, F_GETFL, 0 ) ) < 0 ||
            fcntl( i_handle, F_SETFL, i_flags | O_NONBLOCK ) < 0 )
        {
            msg_Err( p_this, "cannot set socket to non-blocking mode" );
        }
    }
#endif

    /* Connect the socket */
    if( connect( i_handle, (struct sockaddr *) &sock, sizeof( sock ) ) == -1 )
    {
#if defined( WIN32 ) || defined( UNDER_CE )
        if( WSAGetLastError() == WSAEWOULDBLOCK )
#elif defined( HAVE_ERRNO_H )
        if( errno == EINPROGRESS )
#else
        if( 0 )
#endif
        {
            int i_ret;
            int i_opt;
            int i_opt_size = sizeof( i_opt );
            struct timeval  timeout;
            fd_set          fds;

            msg_Dbg( p_this, "connection in progress" );
            do
            {
                if( p_this->b_die )
                {
                    msg_Dbg( p_this, "connection aborted" );
                    goto error;
                }

                /* Initialize file descriptor set */
                FD_ZERO( &fds );
                FD_SET( i_handle, &fds );

                /* We'll wait 0.1 second if nothing happens */
                timeout.tv_sec = 0;
                timeout.tv_usec = 100000;

            } while( ( i_ret = select( i_handle + 1, NULL, &fds, NULL,
                                       &timeout ) ) == 0 ||
#if defined( WIN32 ) || defined( UNDER_CE )
                     ( i_ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK ) );
#elif defined( HAVE_ERRNO_H )
                     ( i_ret < 0 && errno == EINTR ) );
#else
                     ( i_ret < 0 ) );
#endif

            if( i_ret < 0 )
            {
                msg_Warn( p_this, "cannot connect socket (select failed)" );
                goto error;
            }

#if !defined( SYS_BEOS )
            if( getsockopt( i_handle, SOL_SOCKET, SO_ERROR, (void*)&i_opt,
                            &i_opt_size ) == -1 || i_opt != 0 )
            {
                msg_Warn( p_this, "cannot connect socket (SO_ERROR)" );
                goto error;
            }
#endif
        }
        else
        {
#if defined( HAVE_ERRNO_H )
            msg_Warn( p_this, "cannot connect socket (%s)", strerror(errno) );
#else
            msg_Warn( p_this, "cannot connect socket" );
#endif
            goto error;
        }
    }

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

error:
    if( i_handle > 0 )
    {
        close( i_handle );
    }
    return VLC_EGENERIC;
}

/*****************************************************************************
 * NetOpen: wrapper around OpenUDP and OpenTCP
 *****************************************************************************/
static int NetOpen( 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 );
    }
}