Merge pull request #316 from pieterh/master

Fixed issue #358

src/device.cpp

@@ -32,89 +32,63 @@ int zmq::device (class socket_base_t *insocket_,
 {
     msg_t msg;
     int rc = msg.init ();
-
-    if (rc != 0) {
+    if (rc != 0)
         return -1;
-    }
 
-    int64_t more;
+    //  The algorithm below assumes ratio of request and replies processed
+    //  under full load to be 1:1.
+        
+    int more;
     size_t moresz;
-
-    zmq_pollitem_t items [2];
-    items [0].socket = insocket_;
-    items [0].fd = 0;
-    items [0].events = ZMQ_POLLIN;
-    items [0].revents = 0;
-    items [1].socket = outsocket_;
-    items [1].fd = 0;
-    items [1].events = ZMQ_POLLIN;
-    items [1].revents = 0;
-
+    zmq_pollitem_t items [] = {
+        { insocket_, 0, ZMQ_POLLIN, 0 },
+        { outsocket_,  0, ZMQ_POLLIN, 0 }
+    };
     while (true) {
-
         //  Wait while there are either requests or replies to process.
         rc = zmq_poll (&items [0], 2, -1);
-        if (unlikely (rc < 0)) {
+        if (unlikely (rc < 0))
             return -1;
-        }
-
-        //  The algorithm below asumes ratio of request and replies processed
-        //  under full load to be 1:1. Although processing requests replies
-        //  first is tempting it is suspectible to DoS attacks (overloading
-        //  the system with unsolicited replies).
 
         //  Process a request.
         if (items [0].revents & ZMQ_POLLIN) {
             while (true) {
-
                 rc = insocket_->recv (&msg, 0);
-                if (unlikely (rc < 0)) {
+                if (unlikely (rc < 0))
                     return -1;
-                }
-
+                
                 moresz = sizeof (more);
                 rc = insocket_->getsockopt (ZMQ_RCVMORE, &more, &moresz);
-                if (unlikely (rc < 0)) {
+                if (unlikely (rc < 0))
                     return -1;
-                }
-
-                rc = outsocket_->send (&msg, more ? ZMQ_SNDMORE : 0);
-                if (unlikely (rc < 0)) {
+                
+                rc = outsocket_->send (&msg, more? ZMQ_SNDMORE: 0);
+                if (unlikely (rc < 0))
                     return -1;
-                }
-
-                if (!more)
+                if (more == 0)
                     break;
             }
         }
-
         //  Process a reply.
         if (items [1].revents & ZMQ_POLLIN) {
             while (true) {
-
                 rc = outsocket_->recv (&msg, 0);
-                if (unlikely (rc < 0)) {
+                if (unlikely (rc < 0))
                     return -1;
-                }
-
+    
                 moresz = sizeof (more);
                 rc = outsocket_->getsockopt (ZMQ_RCVMORE, &more, &moresz);
-                if (unlikely (rc < 0)) {
+                if (unlikely (rc < 0))
                     return -1;
-                }
-
-                rc = insocket_->send (&msg, more ? ZMQ_SNDMORE : 0);
-                if (unlikely (rc < 0)) {
+                
+                rc = insocket_->send (&msg, more? ZMQ_SNDMORE: 0);
+                if (unlikely (rc < 0))
                     return -1;
-                }
-
-                if (!more)
+                if (more == 0)
                     break;
             }
         }
 
     }
-
     return 0;
 }
-