some minor refactoring to dht callbacks and searches, work in progress

src/yggdrasil/search.go

@@ -33,6 +33,7 @@ const search_RETRY_TIME = time.Second
 // Information about an ongoing search.
 // Includes the target NodeID, the bitmask to match it to an IP, and the list of nodes to visit / already visited.
 type searchInfo struct {
+	core     *Core
 	dest     crypto.NodeID
 	mask     crypto.NodeID
 	time     time.Time
@@ -40,6 +41,7 @@ type searchInfo struct {
 	toVisit  []*dhtInfo
 	visited  map[crypto.NodeID]bool
 	callback func(*sessionInfo, error)
+	// TODO context.Context for timeout and cancellation
 }
 
 // This stores a map of active searches.
@@ -49,7 +51,7 @@ type searches struct {
 	searches    map[crypto.NodeID]*searchInfo
 }
 
-// Intializes the searches struct.
+// Initializes the searches struct.
 func (s *searches) init(core *Core) {
 	s.core = core
 	s.reconfigure = make(chan chan error, 1)
@@ -65,12 +67,13 @@ func (s *searches) init(core *Core) {
 // Creates a new search info, adds it to the searches struct, and returns a pointer to the info.
 func (s *searches) createSearch(dest *crypto.NodeID, mask *crypto.NodeID, callback func(*sessionInfo, error)) *searchInfo {
 	now := time.Now()
-	for dest, sinfo := range s.searches {
-		if now.Sub(sinfo.time) > time.Minute {
-			delete(s.searches, dest)
-		}
-	}
+	//for dest, sinfo := range s.searches {
+	//	if now.Sub(sinfo.time) > time.Minute {
+	//		delete(s.searches, dest)
+	//	}
+	//}
 	info := searchInfo{
+		core:     s.core,
 		dest:     *dest,
 		mask:     *mask,
 		time:     now.Add(-time.Second),
@@ -82,30 +85,29 @@ func (s *searches) createSearch(dest *crypto.NodeID, mask *crypto.NodeID, callba
 
 ////////////////////////////////////////////////////////////////////////////////
 
-// Checks if there's an ongoing search relaed to a dhtRes.
+// Checks if there's an ongoing search related to a dhtRes.
 // If there is, it adds the response info to the search and triggers a new search step.
 // If there's no ongoing search, or we if the dhtRes finished the search (it was from the target node), then don't do anything more.
-func (s *searches) handleDHTRes(res *dhtRes) {
-	sinfo, isIn := s.searches[res.Dest]
-	if !isIn || s.checkDHTRes(sinfo, res) {
+func (sinfo *searchInfo) handleDHTRes(res *dhtRes) {
+	if res == nil || sinfo.checkDHTRes(res) {
 		// Either we don't recognize this search, or we just finished it
 		return
 	}
 	// Add to the search and continue
-	s.addToSearch(sinfo, res)
-	s.doSearchStep(sinfo)
+	sinfo.addToSearch(res)
+	sinfo.doSearchStep()
 }
 
 // Adds the information from a dhtRes to an ongoing search.
 // Info about a node that has already been visited is not re-added to the search.
 // Duplicate information about nodes toVisit is deduplicated (the newest information is kept).
 // The toVisit list is sorted in ascending order of keyspace distance from the destination.
-func (s *searches) addToSearch(sinfo *searchInfo, res *dhtRes) {
+func (sinfo *searchInfo) addToSearch(res *dhtRes) {
 	// Add responses to toVisit if closer to dest than the res node
 	from := dhtInfo{key: res.Key, coords: res.Coords}
 	sinfo.visited[*from.getNodeID()] = true
 	for _, info := range res.Infos {
-		if *info.getNodeID() == s.core.dht.nodeID || sinfo.visited[*info.getNodeID()] {
+		if *info.getNodeID() == sinfo.core.dht.nodeID || sinfo.visited[*info.getNodeID()] {
 			continue
 		}
 		if dht_ordered(&sinfo.dest, info.getNodeID(), from.getNodeID()) {
@@ -135,10 +137,10 @@ func (s *searches) addToSearch(sinfo *searchInfo, res *dhtRes) {
 
 // If there are no nodes left toVisit, then this cleans up the search.
 // Otherwise, it pops the closest node to the destination (in keyspace) off of the toVisit list and sends a dht ping.
-func (s *searches) doSearchStep(sinfo *searchInfo) {
+func (sinfo *searchInfo) doSearchStep() {
 	if len(sinfo.toVisit) == 0 {
 		// Dead end, do cleanup
-		delete(s.searches, sinfo.dest)
+		delete(sinfo.core.searches.searches, sinfo.dest)
 		go sinfo.callback(nil, errors.New("search reached dead end"))
 		return
 	}
@@ -146,31 +148,32 @@ func (s *searches) doSearchStep(sinfo *searchInfo) {
 	var next *dhtInfo
 	next, sinfo.toVisit = sinfo.toVisit[0], sinfo.toVisit[1:]
 	rq := dhtReqKey{next.key, sinfo.dest}
-	s.core.dht.addCallback(&rq, s.handleDHTRes)
-	s.core.dht.ping(next, &sinfo.dest)
+	sinfo.core.dht.addCallback(&rq, sinfo.handleDHTRes)
+	sinfo.core.dht.ping(next, &sinfo.dest)
 }
 
 // If we've recenty sent a ping for this search, do nothing.
 // Otherwise, doSearchStep and schedule another continueSearch to happen after search_RETRY_TIME.
-func (s *searches) continueSearch(sinfo *searchInfo) {
+func (sinfo *searchInfo) continueSearch() {
 	if time.Since(sinfo.time) < search_RETRY_TIME {
 		return
 	}
 	sinfo.time = time.Now()
-	s.doSearchStep(sinfo)
+	sinfo.doSearchStep()
 	// In case the search dies, try to spawn another thread later
 	// Note that this will spawn multiple parallel searches as time passes
 	// Any that die aren't restarted, but a new one will start later
 	retryLater := func() {
-		newSearchInfo := s.searches[sinfo.dest]
+		// FIXME this keeps the search alive forever if not for the searches map, fix that
+		newSearchInfo := sinfo.core.searches.searches[sinfo.dest]
 		if newSearchInfo != sinfo {
 			return
 		}
-		s.continueSearch(sinfo)
+		sinfo.continueSearch()
 	}
 	go func() {
 		time.Sleep(search_RETRY_TIME)
-		s.core.router.admin <- retryLater
+		sinfo.core.router.admin <- retryLater
 	}()
 }
 
@@ -185,37 +188,37 @@ func (s *searches) newIterSearch(dest *crypto.NodeID, mask *crypto.NodeID, callb
 // Checks if a dhtRes is good (called by handleDHTRes).
 // If the response is from the target, get/create a session, trigger a session ping, and return true.
 // Otherwise return false.
-func (s *searches) checkDHTRes(info *searchInfo, res *dhtRes) bool {
+func (sinfo *searchInfo) checkDHTRes(res *dhtRes) bool {
 	them := crypto.GetNodeID(&res.Key)
 	var destMasked crypto.NodeID
 	var themMasked crypto.NodeID
 	for idx := 0; idx < crypto.NodeIDLen; idx++ {
-		destMasked[idx] = info.dest[idx] & info.mask[idx]
-		themMasked[idx] = them[idx] & info.mask[idx]
+		destMasked[idx] = sinfo.dest[idx] & sinfo.mask[idx]
+		themMasked[idx] = them[idx] & sinfo.mask[idx]
 	}
 	if themMasked != destMasked {
 		return false
 	}
 	// They match, so create a session and send a sessionRequest
-	sinfo, isIn := s.core.sessions.getByTheirPerm(&res.Key)
+	sess, isIn := sinfo.core.sessions.getByTheirPerm(&res.Key)
 	if !isIn {
-		sinfo = s.core.sessions.createSession(&res.Key)
-		if sinfo == nil {
+		sess = sinfo.core.sessions.createSession(&res.Key)
+		if sess == nil {
 			// nil if the DHT search finished but the session wasn't allowed
-			go info.callback(nil, errors.New("session not allowed"))
+			go sinfo.callback(nil, errors.New("session not allowed"))
 			return true
 		}
-		_, isIn := s.core.sessions.getByTheirPerm(&res.Key)
+		_, isIn := sinfo.core.sessions.getByTheirPerm(&res.Key)
 		if !isIn {
 			panic("This should never happen")
 		}
 	}
 	// FIXME (!) replay attacks could mess with coords? Give it a handle (tstamp)?
-	sinfo.coords = res.Coords
-	sinfo.packet = info.packet
-	s.core.sessions.ping(sinfo)
-	go info.callback(sinfo, nil)
+	sess.coords = res.Coords
+	sess.packet = sinfo.packet
+	sinfo.core.sessions.ping(sess)
+	go sinfo.callback(sess, nil)
 	// Cleanup
-	delete(s.searches, res.Dest)
+	delete(sinfo.core.searches.searches, res.Dest)
 	return true
 }