repairing unintended hard fork at 745383

src/chainparams.cpp

@@ -144,7 +144,7 @@ public:
         consensus.nAllowMinDiffMaxHeight = -1;
         consensus.nNormalizedNameForkHeight = 539940; // targeting 21 March 2019
         consensus.nMinRemovalWorkaroundHeight = 297706;
-        consensus.nMaxRemovalWorkaroundHeight = 100000000;
+        consensus.nMaxRemovalWorkaroundHeight = 658300;
         consensus.nWitnessForkHeight = 680770; // targeting 11 Dec 2019
         consensus.nAllClaimsInMerkleForkHeight = 658310; // targeting 30 Oct 2019
         consensus.fPowAllowMinDifficultyBlocks = false;
@@ -371,8 +371,8 @@ public:
         consensus.nAllowMinDiffMinHeight = -1;
         consensus.nAllowMinDiffMaxHeight = -1;
         consensus.nNormalizedNameForkHeight = 250; // SDK depends upon this number
-        consensus.nMinRemovalWorkaroundHeight = -1;
-        consensus.nMaxRemovalWorkaroundHeight = -1;
+        consensus.nMinRemovalWorkaroundHeight = 0;
+        consensus.nMaxRemovalWorkaroundHeight = 1000;
         consensus.nWitnessForkHeight = 150;
         consensus.nAllClaimsInMerkleForkHeight = 350;
         consensus.fPowAllowMinDifficultyBlocks = false;

src/claimtrie/trie.cpp

@@ -198,6 +198,27 @@ bool CClaimTrieCacheBase::haveSupportInQueue(const std::string& name, const COut
     return false;
 }
 
+bool emptyNodeShouldExistAt(sqlite::database& db, const std::string& name, int nNextHeight) {
+    auto end = name + std::string(256, std::numeric_limits<char>::max()); // 256 == MAX_CLAIM_NAME_SIZE + 1
+    auto query = db << "SELECT DISTINCT nodeName FROM claim "
+                        "WHERE nodeName BETWEEN ?1 AND ?2 "
+                        "AND activationHeight < ?3 AND expirationHeight >= ?3 "
+                        "ORDER BY nodeName"
+                        << name << end << nNextHeight;
+    std::unordered_set<char> ss;
+    for (auto&& row: query) {
+        std::string nn;
+        row >> nn;
+        if (nn == name)
+            return false;
+        assert(nn.size() > name.size());
+        ss.insert(nn[name.size()]);
+        if (ss.size() > 1)
+            return true;
+    }
+    return false;
+}
+
 bool CClaimTrieCacheBase::deleteNodeIfPossible(const std::string& name, std::string& parent, int64_t& claims)
 {
     if (name.empty()) return false;
@@ -676,20 +697,11 @@ bool CClaimTrieCacheBase::removeClaim(const uint160& claimId, const COutPoint& o
     // because it's a parent one and should not be effectively erased
     // we had a bug in the old code where that situation would force a zero delay on re-add
     if (nNextHeight >= base->nMinRemovalWorkaroundHeight
-        && nNextHeight < base->nMaxRemovalWorkaroundHeight) { // TODO: hard fork this out (which we already tried once but failed)
-        // neither LIKE nor SUBSTR will use an index on a blob, but BETWEEN is a good, fast alternative
-        auto end = nodeName + std::string( 256, std::numeric_limits<char>::max()); // 256 == MAX_CLAIM_NAME_SIZE + 1
-        auto innerQuery = db << "SELECT nodeName FROM claim WHERE nodeName BETWEEN ?1 AND ?2 "
-                           "AND activationHeight < ?3 AND expirationHeight >= ?3 ORDER BY nodeName LIMIT 1"
-                        << nodeName << end << nNextHeight;
-        for (auto&& row: innerQuery) {
-            std::string shortestMatch;
-            row >> shortestMatch;
-            if (shortestMatch != nodeName)
-                // set this when there are no more claims on that name and that node still has children
+        && nNextHeight < base->nMaxRemovalWorkaroundHeight
+        ) {
+        if (emptyNodeShouldExistAt(db, nodeName, nNextHeight))
             removalWorkaround.insert(nodeName);
     }
-    }
     return true;
 }
 
@@ -845,6 +857,17 @@ int CClaimTrieCacheBase::getDelayForName(const std::string& name, const uint160&
         return 0;
     }
 
+    if (!hasCurrentWinner)
+        return 0;
+
+    if (nNextHeight > base->nMaxRemovalWorkaroundHeight) {
+        // TODO: hard fork this out! It's wrong but kept for backwards compatibility
+        // Plan: if we have no claims for this node but we do have multiple children
+        // such that we have an implicit node here then return a 0
+        if (emptyNodeShouldExistAt(db, name, nNextHeight))
+            return 0;
+    }
+    else {
         // NOTE: old code had a bug in it where nodes with no claims but with children would get left in the cache after removal.
         // This would cause the getNumBlocksOfContinuousOwnership to return zero (causing incorrect takeover height calc).
         auto hit = removalWorkaround.find(name);
@@ -852,7 +875,9 @@ int CClaimTrieCacheBase::getDelayForName(const std::string& name, const uint160&
             removalWorkaround.erase(hit);
             return 0;
         }
-    return hasCurrentWinner ? std::min((nNextHeight - winningTakeoverHeight) / base->nProportionalDelayFactor, 4032) : 0;
+    }
+
+    return std::min((nNextHeight - winningTakeoverHeight) / base->nProportionalDelayFactor, 4032);
 }
 
 std::string CClaimTrieCacheBase::adjustNameForValidHeight(const std::string& name, int validHeight) const

src/test/claimtriebranching_tests.cpp

@@ -24,6 +24,32 @@ BOOST_AUTO_TEST_CASE(claim_replace_test) {
     BOOST_CHECK(fixture.is_best_claim("bassfisher", tx2));
 }
 
+BOOST_AUTO_TEST_CASE(triple_update_test)
+{
+    ClaimTrieChainFixture fixture;
+    CMutableTransaction tx1 = fixture.MakeClaim(fixture.GetCoinbase(), "test", "one", 10);
+    fixture.IncrementBlocks(1);
+    CMutableTransaction tx1a = fixture.MakeClaim(fixture.GetCoinbase(), "tester", "one", 3);
+    CMutableTransaction tx2 = fixture.MakeClaim(fixture.GetCoinbase(), "test", "one", 5);
+    auto height = chainActive.Tip()->nHeight;
+    fixture.IncrementBlocks(9);
+
+    CMutableTransaction tx3 = fixture.MakeUpdate(tx1, "test", "two", ClaimIdHash(tx1.GetHash(), 0), 10);
+    CMutableTransaction tx4 = fixture.MakeUpdate(tx2, "test", "two", ClaimIdHash(tx2.GetHash(), 0), 15);
+    CMutableTransaction tx5 = fixture.MakeUpdate(tx4, "test", "two", ClaimIdHash(tx2.GetHash(), 0), 5);
+
+    fixture.IncrementBlocks(1);
+    BOOST_CHECK(fixture.is_best_claim("test", tx3));
+    uint160 id; int takeover;
+    BOOST_REQUIRE(fixture.getLastTakeoverForName("test", id, takeover));
+    BOOST_CHECK_EQUAL(takeover, height);
+    id = ClaimIdHash(tx2.GetHash(), 0);
+    std::string name;
+    CClaimValue value;
+    BOOST_REQUIRE(fixture.getClaimById(id, name, value));
+    BOOST_CHECK_EQUAL(value.nValidAtHeight, height+20);
+}
+
 BOOST_AUTO_TEST_CASE(takeover_stability_test) {
     // no competing bids
     ClaimTrieChainFixture fixture;

src/test/claimtrieexpirationfork_tests.cpp

@@ -823,11 +823,12 @@ BOOST_AUTO_TEST_CASE(removal_workaround_functions)
     fixture.IncrementBlocks(1);
     BOOST_CHECK(fixture.is_best_claim("a", tx3a));
 
-    fixture.IncrementBlocks(7);
-    CMutableTransaction tx4a = fixture.MakeUpdate(tx2a, "b", "b", ClaimIdHash(tx2a.GetHash(), 0), 4);
-    CMutableTransaction tx4b = fixture.MakeUpdate(tx2b, "b", "b", ClaimIdHash(tx2b.GetHash(), 0), 5); // trigger a takeover
-    fixture.IncrementBlocks(1);
-    BOOST_CHECK(fixture.is_best_claim("b", tx4b));
+    // TODO: bring this back after we hard fork out the removal workaround part 2!
+//    fixture.IncrementBlocks(7);
+//    CMutableTransaction tx4a = fixture.MakeUpdate(tx2a, "b", "b", ClaimIdHash(tx2a.GetHash(), 0), 4);
+//    CMutableTransaction tx4b = fixture.MakeUpdate(tx2b, "b", "b", ClaimIdHash(tx2b.GetHash(), 0), 5); // trigger a takeover
+//    fixture.IncrementBlocks(1);
+//    BOOST_CHECK(fixture.is_best_claim("b", tx4b));
 }
 
 BOOST_AUTO_TEST_SUITE_END()