LWIP broadcast

I have developed my own patch that appears to solve the problem. In file udp.c, line 216, replace

ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest)))) {

with

ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest))) ||

ip_addr_isbroadcast(&iphdr->dest, inp) ) {

effectively adding a check for broadcast to one of the many checks of the packet control block. I am not sure this is rigorously correct, but appears to work. Comments invited.

Regards,

Tim

Hi Tim,

I've question regarding your patch.

<div class='quotetop'>QUOTE </div>

--- Quote Start ---

...p_addr_isbroadcast(&iphdr->dest, inp)..[/b]

--- Quote End ---

What kind of type is the variable inp? Because i cannot find a variable in the code that is suitable for that.

Regards,

Peter

EDIT: OK found it by myself :-)

I have simular issue. I have setup the NIOS udp client but when a broadcast message is sent out on the network my receive led flashes but my break point in the udp.c file does not get hit. If I send a regular udp message it does? Whats that all about..

mask = 0xFFFFFF00

IP = 192.168.31.44

PC is broadcasting SO_BROADCAST out

mask 0xFFFFFF00

IP = 192.168.31.45

Used 192.168.31.45 to send out broadcast..

Used 239.0.0.31 to send out broadcast.. above NIOS gets neithe but will receive

a regular udp message to it.

Dear friend,

I am trying to communicate through UDP from nios-ii to my PC ...please send me a sample code. as the one i had write generate lot's of error related to header files.

kaushal

--- Quote Start ---

I have developed my own patch that appears to solve the problem. In file udp.c, line 216, replace

ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest)))) {

with

ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest))) ||

ip_addr_isbroadcast(&iphdr->dest, inp) ) {

effectively adding a check for broadcast to one of the many checks of the packet control block. I am not sure this is rigorously correct, but appears to work. Comments invited.

Regards,

Tim

--- Quote End ---

Tim, please join the lwip-users mailing list and submit the problem and your proposed solution. Development on lwIP is active as a new major upgrade is in the works. You didn't mention lwIP version and you'll need to do this there. Here would have been nice too. :)

https://savannah.nongnu.org/mail/?group=lwip

Bill

Hello all,

I read discussion about broadcast listening, but i need to send broadcast from nios to network, could you advise me:

I include code:

----------------------------

void udp_init_all(void)

{

// proved nastaveni ciloveho adresata soketoveho spojeni

host = gethostbyname("192.168.3.255");

if(host==NULL)

{ printf("Address error.");

return;

}

// nastav struktury a cilovy port adresata

remoteServAddr.sin_family = host->h_addrtype;

memcpy((char *) &remoteServAddr.sin_addr.s_addr, host->h_addr_list[0], host->h_length);

// remoteServAddr.sin_port = htons(serverPort);

// navaz sitove spojeni

if ((socketDescriptor = socket(AF_INET, SOCK_DGRAM, 0)) < 0)

{ printf("Not able to create socket connection. \n");

return;

// exit(1);

}

serverAddress.sin_family = AF_INET;

serverAddress.sin_addr.s_addr = inet_addr(SRC_IP_ADR); //"192.168.3.238");

}

--------------------------

and sending code:

--------------------------

// nastav adresu portu a posli udp paket

remoteServAddr.sin_port = htons(serverPort);

if (sendto(socketDescriptor, out_buf, len, 0,

(struct sockaddr *) &remoteServAddr, sizeof(remoteServAddr)) < 0)

{ printf("I am not able to send data to remote server.\n");

// close(socketDescriptor);

return;

// exit(1);

}

-----------------------------

and sending code report me:

I am not able to send data to remote server.

What should I change ? Where is error ?

Jan Naceradsky, Altera