When a dpnode finds the answer, write it to the controller

dpnode.cc

@@ -45,7 +45,9 @@ static void dpnode_event_cb(struct bufferevent *bev, short events,
     void *ctx)
 {
     if (events & (BEV_EVENT_EOF|BEV_EVENT_ERROR)) {
-	fprintf(stderr, "Closing connection\n");
+	fprintf(stderr, "Closing connection (%s%s)\n",
+	    (events & BEV_EVENT_EOF) ? "EOF" : "",
+	    (events & BEV_EVENT_ERROR) ? "ERR" : "");
 	DPNodeConnInfo *info = (DPNodeConnInfo*)ctx;
 	delete info;
 	bufferevent_free(bev);
@@ -63,6 +65,7 @@ static void dpnode_reader(struct bufferevent *bev, void *ctx)
 	size_t len = evbuffer_get_length(input);
 	if (len < ((WORDS+6)*sizeof(unsigned int))) break;
 	bufferevent_read(bev, dp, (WORDS+6)*sizeof(unsigned int));
+	if (dpctrlstate.current_problem == NULL) continue;
 	// The (WORDS+6) unsigned ints we read are:
 	// - WORDS words for the value of the dp
 	// - 3 words for a
@@ -80,8 +83,8 @@ static void dpnode_reader(struct bufferevent *bev, void *ctx)
 	if (!res.second) {
 	    const ZZ& order = dpctrlstate.current_problem->order;
 	    // Collision!
-	    ZZ adiff = to_ZZ(res.first->second.first) - zz_a;
-	    ZZ bdiff = zz_b - to_ZZ(res.first->second.second);
+	    ZZ adiff = res.first->second.first - zz_a;
+	    ZZ bdiff = zz_b - res.first->second.second;
 	    while (bdiff < 0) bdiff += order;
 	    while (bdiff >= order) bdiff -= order;
 	    while (adiff < 0) adiff += order;
@@ -90,11 +93,15 @@ static void dpnode_reader(struct bufferevent *bev, void *ctx)
 	    if (InvModStatus(binv, bdiff, order) == 0) {
 		ZZ expon = MulMod(binv, adiff, order);
 		cerr << "Collision after " << dpctrlstate.numdps << " DPs\n";
-		unsigned char exponbytes[3*sizeof(unsigned int)];
-		BytesFromZZ(exponbytes, expon, 3*sizeof(unsigned int));
+		unsigned char exponbytes[3+3*sizeof(unsigned int)];
+		exponbytes[0] = 'E';
+		memmove(exponbytes+1,
+			&(dpctrlstate.current_problem->problemid), 2);
+		BytesFromZZ(exponbytes+3, expon, 3*sizeof(unsigned int));
 		bufferevent_write(dpctrlstate.controller_bev, exponbytes,
-		    3*sizeof(unsigned int));
+		    3+3*sizeof(unsigned int));
 		stop_problem();
+		return;
 	    }
 	}
 	++dpctrlstate.numdps;
@@ -142,6 +149,7 @@ struct DPControllerConnInfo {
 static void stop_problem(void)
 {
     if (dpctrlstate.current_problem) {
+	delete dpctrlstate.current_problem;
 	dpctrlstate.current_problem = NULL;
     }
     if (dpctrlstate.listener) {