Request-reply broker in C

// Simple request-reply broker

#include "zhelpers.h"

int main (void)
{
// Prepare our context and sockets
void *context = zmq_ctx_new ();
void *frontend = zmq_socket (context, ZMQ_ROUTER);
void *backend = zmq_socket (context, ZMQ_DEALER);
zmq_bind (frontend, "tcp://*:5559");
zmq_bind (backend, "tcp://*:5560");

// Initialize poll set
zmq_pollitem_t items [] = {
{ frontend, 0, ZMQ_POLLIN, 0 },
{ backend, 0, ZMQ_POLLIN, 0 }
};
// Switch messages between sockets
while (1) {
zmq_msg_t message;
zmq_poll (items, 2, -1);
if (items [0].revents & ZMQ_POLLIN) {
while (1) {
// Process all parts of the message
zmq_msg_init (&message);
zmq_msg_recv (&message, frontend, 0);
int more = zmq_msg_more (&message);
zmq_msg_send (&message, backend, more? ZMQ_SNDMORE: 0);
zmq_msg_close (&message);
if (!more)
break; // Last message part
}
}
if (items [1].revents & ZMQ_POLLIN) {
while (1) {
// Process all parts of the message
zmq_msg_init (&message);
zmq_msg_recv (&message, backend, 0);
int more = zmq_msg_more (&message);
zmq_msg_send (&message, frontend, more? ZMQ_SNDMORE: 0);
zmq_msg_close (&message);
if (!more)
break; // Last message part
}
}
}
// We never get here, but clean up anyhow
zmq_close (frontend);
zmq_close (backend);
zmq_ctx_destroy (context);
return 0;
}