core/state, trie: surface iterator entry hashes

6 files changed, 114 insertions, 20 deletions

diff --git a/core/state/iterator.go b/core/state/iterator.go
index a0b71f3ee..59a8e0242 100644
--- a/core/state/iterator.go
+++ b/core/state/iterator.go
@@ -33,8 +33,11 @@ type NodeIterator struct {
 
 	stateIt *trie.NodeIterator // Primary iterator for the global state trie
 	dataIt  *trie.NodeIterator // Secondary iterator for the data trie of a contract
-	code    []byte             // Source code associated with a contract
 
+	codeHash common.Hash // Hash of the contract source code
+	code     []byte      // Source code associated with a contract
+
+	Hash  common.Hash // Hash of the current entry being iterated (nil if not standalone)
 	Entry interface{} // Current state entry being iterated (internal representation)
 }
 
@@ -103,6 +106,7 @@ func (it *NodeIterator) step() {
 		it.dataIt = nil
 	}
 	if bytes.Compare(account.CodeHash, emptyCodeHash) != 0 {
+		it.codeHash = common.BytesToHash(account.CodeHash)
 		it.code, err = it.state.db.Get(account.CodeHash)
 		if err != nil {
 			panic(fmt.Sprintf("code %x: %v", account.CodeHash, err))
@@ -114,7 +118,7 @@ func (it *NodeIterator) step() {
 // The method returns whether there are any more data left for inspection.
 func (it *NodeIterator) retrieve() bool {
 	// Clear out any previously set values
-	it.Entry = nil
+	it.Hash, it.Entry = common.Hash{}, nil
 
 	// If the iteration's done, return no available data
 	if it.state == nil {
@@ -123,11 +127,11 @@ func (it *NodeIterator) retrieve() bool {
 	// Otherwise retrieve the current entry
 	switch {
 	case it.dataIt != nil:
-		it.Entry = it.dataIt.Node
+		it.Hash, it.Entry = it.dataIt.Hash, it.dataIt.Node
 	case it.code != nil:
-		it.Entry = it.code
+		it.Hash, it.Entry = it.codeHash, it.code
 	case it.stateIt != nil:
-		it.Entry = it.stateIt.Node
+		it.Hash, it.Entry = it.stateIt.Hash, it.stateIt.Node
 	}
 	return true
 }
diff --git a/core/state/iterator_test.go b/core/state/iterator_test.go
new file mode 100644
index 000000000..8b68870c6
--- /dev/null
+++ b/core/state/iterator_test.go
@@ -0,0 +1,57 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package state
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/ethdb"
+)
+
+// Tests that the node iterator indeed walks over the entire database contents.
+func TestNodeIteratorCoverage(t *testing.T) {
+	// Create some arbitrary test state to iterate
+	db, root, _ := makeTestState()
+
+	state, err := New(root, db)
+	if err != nil {
+		t.Fatalf("failed to create state trie at %x: %v", root, err)
+	}
+	// Gather all the node hashes found by the iterator
+	hashes := make(map[common.Hash]struct{})
+	for it := NewNodeIterator(state); it.Next(); {
+		if it.Hash != (common.Hash{}) {
+			hashes[it.Hash] = struct{}{}
+		}
+	}
+	// Cross check the hashes and the database itself
+	for hash, _ := range hashes {
+		if _, err := db.Get(hash.Bytes()); err != nil {
+			t.Errorf("failed to retrieve reported node %x: %v", hash, err)
+		}
+	}
+	for _, key := range db.(*ethdb.MemDatabase).Keys() {
+		if bytes.HasPrefix(key, []byte("secure-key-")) {
+			continue
+		}
+		if _, ok := hashes[common.BytesToHash(key)]; !ok {
+			t.Errorf("state entry not reported %x", key)
+		}
+	}
+}
diff --git a/core/state/sync_test.go b/core/state/sync_test.go
index 5d6d90d5d..727a276a5 100644
--- a/core/state/sync_test.go
+++ b/core/state/sync_test.go
@@ -116,8 +116,7 @@ func checkStateConsistency(db ethdb.Database, root common.Hash) (failure error)
 	if err != nil {
 		return
 	}
-	it := NewNodeIterator(state)
-	for it.Next() {
+	for it := NewNodeIterator(state); it.Next(); {
 	}
 	return nil
 }
diff --git a/trie/iterator.go b/trie/iterator.go
index e79de2e4e..12ca96bd1 100644
--- a/trie/iterator.go
+++ b/trie/iterator.go
@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"fmt"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
 )
@@ -152,8 +153,9 @@ func (self *Iterator) key(node interface{}) []byte {
 // nodeIteratorState represents the iteration state at one particular node of the
 // trie, which can be resumed at a later invocation.
 type nodeIteratorState struct {
-	node  node // Trie node being iterated
-	child int  // Child to be processed next
+	hash  common.Hash // Hash of the node being iterated (nil if not standalone)
+	node  node        // Trie node being iterated
+	child int         // Child to be processed next
 }
 
 // NodeIterator is an iterator to traverse the trie post-order.
@@ -161,9 +163,10 @@ type NodeIterator struct {
 	trie  *Trie                // Trie being iterated
 	stack []*nodeIteratorState // Hierarchy of trie nodes persisting the iteration state
 
-	Node     node   // Current node being iterated (internal representation)
-	Leaf     bool   // Flag whether the current node is a value (data) node
-	LeafBlob []byte // Data blob contained within a leaf (otherwise nil)
+	Hash     common.Hash // Hash of the current node being iterated (nil if not standalone)
+	Node     node        // Current node being iterated (internal representation)
+	Leaf     bool        // Flag whether the current node is a value (data) node
+	LeafBlob []byte      // Data blob contained within a leaf (otherwise nil)
 }
 
 // NewNodeIterator creates an post-order trie iterator.
@@ -221,18 +224,18 @@ func (it *NodeIterator) step() {
 			}
 			parent.child++
 			it.stack = append(it.stack, &nodeIteratorState{node: node.Val, child: -1})
-		} else if node, ok := parent.node.(hashNode); ok {
+		} else if hash, ok := parent.node.(hashNode); ok {
 			// Hash node, resolve the hash child from the database, then the node itself
 			if parent.child >= 0 {
 				break
 			}
 			parent.child++
 
-			node, err := it.trie.resolveHash(node, nil, nil)
+			node, err := it.trie.resolveHash(hash, nil, nil)
 			if err != nil {
 				panic(err)
 			}
-			it.stack = append(it.stack, &nodeIteratorState{node: node, child: -1})
+			it.stack = append(it.stack, &nodeIteratorState{hash: common.BytesToHash(hash), node: node, child: -1})
 		} else {
 			break
 		}
@@ -246,14 +249,16 @@ func (it *NodeIterator) step() {
 // The method returns whether there are any more data left for inspection.
 func (it *NodeIterator) retrieve() bool {
 	// Clear out any previously set values
-	it.Node, it.Leaf, it.LeafBlob = nil, false, nil
+	it.Hash, it.Node, it.Leaf, it.LeafBlob = common.Hash{}, nil, false, nil
 
 	// If the iteration's done, return no available data
 	if it.trie == nil {
 		return false
 	}
 	// Otherwise retrieve the current node and resolve leaf accessors
-	it.Node = it.stack[len(it.stack)-1].node
+	state := it.stack[len(it.stack)-1]
+
+	it.Hash, it.Node = state.hash, state.node
 	if value, ok := it.Node.(valueNode); ok {
 		it.Leaf, it.LeafBlob = true, []byte(value)
 	}
diff --git a/trie/iterator_test.go b/trie/iterator_test.go
index fdc60b412..dc8276116 100644
--- a/trie/iterator_test.go
+++ b/trie/iterator_test.go
@@ -16,7 +16,12 @@
 
 package trie
 
-import "testing"
+import (
+	"testing"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/ethdb"
+)
 
 func TestIterator(t *testing.T) {
 	trie := newEmpty()
@@ -47,3 +52,28 @@ func TestIterator(t *testing.T) {
 		}
 	}
 }
+
+// Tests that the node iterator indeed walks over the entire database contents.
+func TestNodeIteratorCoverage(t *testing.T) {
+	// Create some arbitrary test trie to iterate
+	db, trie, _ := makeTestTrie()
+
+	// Gather all the node hashes found by the iterator
+	hashes := make(map[common.Hash]struct{})
+	for it := NewNodeIterator(trie); it.Next(); {
+		if it.Hash != (common.Hash{}) {
+			hashes[it.Hash] = struct{}{}
+		}
+	}
+	// Cross check the hashes and the database itself
+	for hash, _ := range hashes {
+		if _, err := db.Get(hash.Bytes()); err != nil {
+			t.Errorf("failed to retrieve reported node %x: %v", hash, err)
+		}
+	}
+	for _, key := range db.(*ethdb.MemDatabase).Keys() {
+		if _, ok := hashes[common.BytesToHash(key)]; !ok {
+			t.Errorf("state entry not reported %x", key)
+		}
+	}
+}
diff --git a/trie/sync_test.go b/trie/sync_test.go
index 94d6edd68..ce098d5a0 100644
--- a/trie/sync_test.go
+++ b/trie/sync_test.go
@@ -96,8 +96,7 @@ func checkTrieConsistency(db Database, root common.Hash) (failure error) {
 	if err != nil {
 		return
 	}
-	it := NewNodeIterator(trie)
-	for it.Next() {
+	for it := NewNodeIterator(trie); it.Next(); {
 	}
 	return nil
 }