Fix tracking of ancients

We had been assuming that the `item` returned from batch.commit()
was the item committed, but it's actually the next item to be added
to the freezer, and multiple items can be committed in a single batch.

This commit finds the smallest item in the freezer and iterates from
that to the number returned by commit(), passing any tracked blocks
in that range to plugins.

core/rawdb/plugin_hooks.go

@@ -37,77 +37,83 @@ func PluginCommitUpdate(pl *plugins.PluginLoader, num uint64) {
 	lock.Lock()
 	defer lock.Unlock()
 	if freezerUpdates == nil { freezerUpdates = make(map[uint64]map[string]interface{}) }
-	defer func() { delete(freezerUpdates, num) }()
-	update, ok := freezerUpdates[num]
-	if !ok {
-		log.Warn("Attempting to commit untracked block", "num", num)
-		return
+	min := ^uint64(0)
+	for i := range freezerUpdates{
+		if min < i { min = i }
 	}
-	fnList := pl.Lookup("ModifyAncients", func(item interface{}) bool {
-		_, ok := item.(func(uint64, map[string]interface{}))
-		return ok
-	})
-	for _, fni := range fnList {
-		if fn, ok := fni.(func(uint64, map[string]interface{})); ok {
-			fn(num, update)
+	for i := min ; i < num; i++ {
+		update, ok := freezerUpdates[i]
+		defer func() { delete(freezerUpdates, i) }()
+		if !ok {
+			log.Warn("Attempting to commit untracked block", "num", i)
+			continue
 		}
-	}
-	appendAncientFnList := pl.Lookup("AppendAncient", func(item interface{}) bool {
-		_, ok := item.(func(number uint64, hash, header, body, receipts, td []byte))
-		if ok { log.Warn("PlugEth's AppendAncient is deprecated. Please update to ModifyAncients.") }
-		return ok
-	})
-	if len(appendAncientFnList) > 0 {
-		var (
-			hash []byte
-			header []byte
-			body []byte
-			receipts []byte
-			td []byte
-		)
-		if hashi, ok := update[freezerHashTable]; ok {
-			switch v := hashi.(type) {
-			case []byte:
-				hash = v
-			default:
-				hash, _ = rlp.EncodeToBytes(v)
+		fnList := pl.Lookup("ModifyAncients", func(item interface{}) bool {
+			_, ok := item.(func(uint64, map[string]interface{}))
+			return ok
+		})
+		for _, fni := range fnList {
+			if fn, ok := fni.(func(uint64, map[string]interface{})); ok {
+				fn(i, update)
 			}
 		}
-		if headeri, ok := update[freezerHeaderTable]; ok {
-			switch v := headeri.(type) {
-			case []byte:
-				header = v
-			default:
-				header, _ = rlp.EncodeToBytes(v)
+		appendAncientFnList := pl.Lookup("AppendAncient", func(item interface{}) bool {
+			_, ok := item.(func(number uint64, hash, header, body, receipts, td []byte))
+			if ok { log.Warn("PlugEth's AppendAncient is deprecated. Please update to ModifyAncients.") }
+			return ok
+		})
+		if len(appendAncientFnList) > 0 {
+			var (
+				hash []byte
+				header []byte
+				body []byte
+				receipts []byte
+				td []byte
+			)
+			if hashi, ok := update[freezerHashTable]; ok {
+				switch v := hashi.(type) {
+				case []byte:
+					hash = v
+				default:
+					hash, _ = rlp.EncodeToBytes(v)
+				}
 			}
-		}
-		if bodyi, ok := update[freezerBodiesTable]; ok {
-			switch v := bodyi.(type) {
-			case []byte:
-				body = v
-			default:
-				body, _ = rlp.EncodeToBytes(v)
+			if headeri, ok := update[freezerHeaderTable]; ok {
+				switch v := headeri.(type) {
+				case []byte:
+					header = v
+				default:
+					header, _ = rlp.EncodeToBytes(v)
+				}
 			}
-		}
-		if receiptsi, ok := update[freezerReceiptTable]; ok {
-			switch v := receiptsi.(type) {
-			case []byte:
-				receipts = v
-			default:
-				receipts, _ = rlp.EncodeToBytes(v)
+			if bodyi, ok := update[freezerBodiesTable]; ok {
+				switch v := bodyi.(type) {
+				case []byte:
+					body = v
+				default:
+					body, _ = rlp.EncodeToBytes(v)
+				}
 			}
-		}
-		if tdi, ok := update[freezerDifficultyTable]; ok {
-			switch v := tdi.(type) {
-			case []byte:
-				td = v
-			default:
-				td, _ = rlp.EncodeToBytes(v)
+			if receiptsi, ok := update[freezerReceiptTable]; ok {
+				switch v := receiptsi.(type) {
+				case []byte:
+					receipts = v
+				default:
+					receipts, _ = rlp.EncodeToBytes(v)
+				}
 			}
-		}
-		for _, fni := range appendAncientFnList {
-			if fn, ok := fni.(func(number uint64, hash, header, body, receipts, td []byte)); ok {
-				fn(num, hash, header, body, receipts, td)
+			if tdi, ok := update[freezerDifficultyTable]; ok {
+				switch v := tdi.(type) {
+				case []byte:
+					td = v
+				default:
+					td, _ = rlp.EncodeToBytes(v)
+				}
+			}
+			for _, fni := range appendAncientFnList {
+				if fn, ok := fni.(func(number uint64, hash, header, body, receipts, td []byte)); ok {
+					fn(i, hash, header, body, receipts, td)
+				}
 			}
 		}
 	}