ipv4.c

uclinux 下的vlc播放器源代码

    /* Bind it */
    if( bind( i_handle, (struct sockaddr *)&loc, sizeof( loc ) ) < 0 )
    {
        msg_Warn( p_this, "cannot bind socket (%s)", strerror(errno) );
        close( i_handle );
        return 0;
    }

#if !defined( SYS_BEOS )
    /* Allow broadcast reception if we bound on INADDR_ANY */
    if( loc.sin_addr.s_addr == INADDR_ANY )
    {
        i_opt = 1;
        if( setsockopt( i_handle, SOL_SOCKET, SO_BROADCAST, (void*) &i_opt,
                        sizeof( i_opt ) ) == -1 )
            msg_Warn( p_this, "cannot configure socket (SO_BROADCAST: %s)",
                       strerror(errno) );
    }
#endif

#if !defined( SYS_BEOS )
    /* Join the multicast group if the socket is a multicast address */
    if( IN_MULTICAST( ntohl(loc.sin_addr.s_addr) ) )
    {
        /* Determine interface to be used for multicast */
        char * psz_if_addr = config_GetPsz( p_this, "miface-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 (( rem.sin_addr.s_addr != INADDR_ANY )
         /*&& ((ntohl (loc.sin_addr.s_addr) >> 24) == 232)*/)
        {
#ifndef IP_ADD_SOURCE_MEMBERSHIP
            errno = ENOSYS;
#else
            struct ip_mreq_source imr;

            imr.imr_multiaddr.s_addr = loc.sin_addr.s_addr;
            imr.imr_sourceaddr.s_addr = rem.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_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) ) == 0 )
                do_connect = VLC_FALSE;
            else
#endif
            {
                msg_Warn( p_this, "Source specific multicast failed (%s) -"
                          " check if your OS really supports IGMPv3",
                          strerror(errno) );
                goto igmpv2;
            }
        }
        /* If there is no source address, we use IP_ADD_MEMBERSHIP */
        else
igmpv2:
        {
            struct ip_mreq imr;

            imr.imr_interface.s_addr = INADDR_ANY;
            imr.imr_multiaddr.s_addr = loc.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);
            }
#if defined (WIN32) || defined (UNDER_CE)
            else
            {
                typedef DWORD (CALLBACK * GETBESTINTERFACE) ( IPAddr, PDWORD );
                typedef DWORD (CALLBACK * GETIPADDRTABLE) ( PMIB_IPADDRTABLE, PULONG, BOOL );

                GETBESTINTERFACE OurGetBestInterface;
                GETIPADDRTABLE OurGetIpAddrTable;
                HINSTANCE hiphlpapi = LoadLibrary(_T("Iphlpapi.dll"));
                DWORD i_index;

                if( hiphlpapi )
                {
                    OurGetBestInterface =
                        (void *)GetProcAddress( hiphlpapi,
                                                _T("GetBestInterface") );
                    OurGetIpAddrTable =
                        (void *)GetProcAddress( hiphlpapi,
                                                _T("GetIpAddrTable") );
                }

                if( hiphlpapi && OurGetBestInterface && OurGetIpAddrTable &&
                    OurGetBestInterface( loc.sin_addr.s_addr,
                                         &i_index ) == NO_ERROR )
                {
                    PMIB_IPADDRTABLE p_table;
                    DWORD i = 0;

                    msg_Dbg( p_this, "Winsock best interface is %lu",
                             (unsigned long)i_index );
                    OurGetIpAddrTable( NULL, &i, 0 );

                    p_table = (PMIB_IPADDRTABLE)malloc( i );
                    if( p_table != NULL )
                    {
                        if( OurGetIpAddrTable( p_table, &i, 0 ) == NO_ERROR )
                        {
                            for( i = 0; i < p_table->dwNumEntries; i-- )
                            {
                                if( p_table->table[i].dwIndex == i_index )
                                {
                                    imr.imr_interface.s_addr =
                                                     p_table->table[i].dwAddr;
                                    msg_Dbg( p_this, "using interface 0x%08x",
                                             p_table->table[i].dwAddr );
                                }
                            }
                        }
                        else msg_Warn( p_this, "GetIpAddrTable failed" );
                        free( p_table );
                    }
                }
                else msg_Dbg( p_this, "GetBestInterface failed" );

                if( hiphlpapi ) FreeLibrary( hiphlpapi );
            }
#endif
            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 )
            {
                msg_Err( p_this, "failed to join IP multicast group (%s)",
                                  strerror(errno) );
                close( i_handle );
                return 0;
            }
         }
    }

#if !defined (__linux__) && !defined (WIN32)
    else
#endif

#endif /* !defined SYS_BEOS */

    if( rem.sin_addr.s_addr != INADDR_ANY )
    {
        /* Connect the socket */
        if( do_connect
         && connect( i_handle, (struct sockaddr *) &rem, sizeof( rem ) ) )
        {
            msg_Warn( p_this, "cannot connect socket (%s)", strerror(errno) );
            close( i_handle );
            return 0;
        }

#if !defined( SYS_BEOS )
        if( IN_MULTICAST( ntohl(rem.sin_addr.s_addr) ) )
        {
            /* set the time-to-live */
            int i_ttl = p_socket->i_ttl;

            /* set the multicast interface */
            char * psz_mif_addr = config_GetPsz( p_this, "miface-addr" );
            if( psz_mif_addr )
            {
                struct in_addr intf;
                intf.s_addr = inet_addr(psz_mif_addr);
                free( psz_mif_addr  );

                if( setsockopt( i_handle, IPPROTO_IP, IP_MULTICAST_IF,
                                &intf, sizeof( intf ) ) < 0 )
                {
                    msg_Dbg( p_this, "failed to set multicast interface (%s).", strerror(errno) );
                    close( i_handle );
                    return 0;
                }
            }

            if( i_ttl <= 0 )
                i_ttl = config_GetInt( p_this, "ttl" );

            if( i_ttl > 0 )
            {
                unsigned char ttl = (unsigned char) i_ttl;

                /* There is some confusion in the world whether IP_MULTICAST_TTL 
                * takes a byte or an int as an argument.
                * BSD seems to indicate byte so we are going with that and use
                * int as a fallback to be safe */
                if( setsockopt( i_handle, IPPROTO_IP, IP_MULTICAST_TTL,
                                &ttl, sizeof( ttl ) ) < 0 )
                {
                    msg_Dbg( p_this, "failed to set ttl (%s). Let's try it "
                            "the integer way.", strerror(errno) );
                    if( setsockopt( i_handle, IPPROTO_IP, IP_MULTICAST_TTL,
                                    &i_ttl, sizeof( i_ttl ) ) <0 )
                    {
                        msg_Err( p_this, "failed to set ttl (%s)",
                                strerror(errno) );
                        close( i_handle );
                        return 0;
                    }
                }
            }
        }
#endif
    }

    p_socket->i_handle = i_handle;

    if( var_Get( p_this, "mtu", &val ) != VLC_SUCCESS )
    {
        var_Create( p_this, "mtu", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
        var_Get( p_this, "mtu", &val );
    }
    p_socket->i_mtu = val.i_int;

    return 0;
}