don't assume the fastest dht node to be the most up-to-date on a given resource.

that is, now we also enable multiple replies collecting for non-multi entries.
default parameter is a very small timeout for additional replies: that's a tradeoff between probability of getting an older value x slowing the UI.

src/twister.cpp

@@ -1339,6 +1339,7 @@ Value dhtget(const Array& params, bool fHelp)
     time_duration timeToWait = seconds(10);
     time_duration timeToWaitMulti = milliseconds(100);
     int minMultiReplies = 3;
+    int lastSeq = -1;
 
     if( params.size() > 3 )
         timeToWait = milliseconds(params[3].get_int());
@@ -1372,12 +1373,17 @@ Value dhtget(const Array& params, bool fHelp)
                 libtorrent::entry &e = *it;
                 hexcapeDht( e );
                 string sig_p = safeGetEntryString(e, "sig_p");
-                if( !sig_p.length() ) {
+                int seq = (multi) ? 0 : safeGetEntryInt( safeGetEntryDict(e,"p"), "seq" );
+                bool acceptEntry = (multi) ? (!sig_p.length() || !uniqueSigPs.count(sig_p)) :
+                                             (seq > lastSeq);
+                if( acceptEntry ) {
+                    if( !multi) {
+                        ret.clear();
+                    }
                     ret.push_back( entryToJson(e) );
-                } else {
-                    if( !uniqueSigPs.count(sig_p) ) {
+                    lastSeq = seq;
+                    if( sig_p.length() ) {
                         uniqueSigPs.insert(sig_p);
-                        ret.push_back( entryToJson(e) );
                     }
                 }
             }
@@ -1387,13 +1393,9 @@ Value dhtget(const Array& params, bool fHelp)
             break;
         }
 
-        if( multi ) {
-            if( repliesReceived++ < minMultiReplies && uniqueSigPs.size() ) {
+        if( repliesReceived++ < minMultiReplies ) {
             timeToWait = timeToWaitMulti;
-                //printf("dhtget: wait again %d\n", repliesReceived);
-            } else {
-                break;
-            }
+            //printf("dhtget: wait again repliesReceived=%d lastSeq=%d\n", repliesReceived, lastSeq);
         } else {
             break;
         }

src/twister_utils.cpp

@@ -329,7 +329,7 @@ void unHexcapeDht(libtorrent::entry &e)
     }
 }
 
-std::string safeGetEntryString(libtorrent::entry &e, std::string const& key)
+std::string safeGetEntryString(libtorrent::entry const &e, std::string const& key)
 {
     if( e.type() == libtorrent::entry::dictionary_t &&
         e.find_key(key) && e[key].type() == libtorrent::entry::string_t ) {
@@ -339,3 +339,24 @@ std::string safeGetEntryString(libtorrent::entry &e, std::string const& key)
     }
 }
 
+int safeGetEntryInt(libtorrent::entry const &e, std::string const& key)
+{
+    if( e.type() == libtorrent::entry::dictionary_t &&
+        e.find_key(key) && e[key].type() == libtorrent::entry::int_t ) {
+        return e[key].integer();
+    } else {
+        return 0;
+    }
+}
+
+libtorrent::entry safeGetEntryDict(libtorrent::entry const &e, std::string const& key)
+{
+    static libtorrent::entry::dictionary_type dummy;
+    if( e.type() == libtorrent::entry::dictionary_t &&
+        e.find_key(key) && e[key].type() == libtorrent::entry::dictionary_t ) {
+        return e[key].dict();
+    } else {
+        return dummy;
+    }
+}
+

src/twister_utils.h

@@ -44,6 +44,8 @@ void unHexcapePost(libtorrent::entry &e);
 void hexcapeDht(libtorrent::entry &e);
 void unHexcapeDht(libtorrent::entry &e);
 
-std::string safeGetEntryString(libtorrent::entry &e, std::string const& key);
+std::string safeGetEntryString(libtorrent::entry const &e, std::string const& key);
+int safeGetEntryInt(libtorrent::entry const &e, std::string const& key);
+libtorrent::entry safeGetEntryDict(libtorrent::entry const &e, std::string const& key);
 
 #endif // TWISTER_UTILS_H