Change WriteSyncSegment to take a common.Hash instead of []byte to enforce a length of 32 bytes

Author: qdm12

core/rawdb/accessors_state_sync.go

@@ -77,7 +77,7 @@ func NewSyncSegmentsIterator(db ethdb.Iteratee, root common.Hash) ethdb.Iterator
 }
 
 // WriteSyncSegment adds a trie segment for root at the given start position.
-func WriteSyncSegment(db ethdb.KeyValueWriter, root common.Hash, start []byte) error {
+func WriteSyncSegment(db ethdb.KeyValueWriter, root common.Hash, start common.Hash) error {
 	return db.Put(packSyncSegmentKey(root, start), []byte{0x01})
 }
 
@@ -104,14 +104,11 @@ func UnpackSyncSegmentKey(keyBytes []byte) (common.Hash, []byte) {
 }
 
 // packSyncSegmentKey packs root and account into a key for storage in db.
-func packSyncSegmentKey(root common.Hash, start []byte) []byte {
-	if len(start) != common.HashLength {
-		panic("start must be 32 bytes")
-	}
+func packSyncSegmentKey(root common.Hash, start common.Hash) []byte {
 	bytes := make([]byte, syncSegmentsKeyLength)
 	copy(bytes, syncSegmentsPrefix)
 	copy(bytes[len(syncSegmentsPrefix):], root[:])
-	copy(bytes[len(syncSegmentsPrefix)+common.HashLength:], start)
+	copy(bytes[len(syncSegmentsPrefix)+common.HashLength:], start.Bytes())
 	return bytes
 }
 

core/rawdb/accessors_state_sync_test.go

@@ -14,7 +14,7 @@ func TestClearPrefix(t *testing.T) {
 	require := require.New(t)
 	db := NewMemoryDatabase()
 	// add a key that should be cleared
-	require.NoError(WriteSyncSegment(db, common.Hash{1}, common.Hash{}.Bytes()))
+	require.NoError(WriteSyncSegment(db, common.Hash{1}, common.Hash{}))
 
 	// add a key that should not be cleared
 	key := append(syncSegmentsPrefix, []byte("foo")...)

core/rawdb/database_ext_test.go

@@ -16,7 +16,7 @@ func ExampleInspectDatabase() {
 	WriteSnapshotBlockHash(db, common.Hash{})
 	WriteSnapshotRoot(db, common.Hash{})
 	// Trie segments: (77 + 2) + 1 = 80 bytes
-	_ = WriteSyncSegment(db, common.Hash{}, common.Hash{}.Bytes())
+	_ = WriteSyncSegment(db, common.Hash{}, common.Hash{})
 	// Storage tries to fetch: 76 + 1 = 77 bytes
 	_ = WriteSyncStorageTrie(db, common.Hash{}, common.Hash{})
 	// Code to fetch: 34 + 0 = 34 bytes

sync/statesync/trie_segments.go

@@ -301,7 +301,7 @@ func (t *trieToSync) createSegments(numSegments int) error {
 
 		// create the segments
 		segment := t.addSegment(startBytes, endBytes)
-		if err := rawdb.WriteSyncSegment(t.sync.db, t.root, segment.start); err != nil {
+		if err := rawdb.WriteSyncSegment(t.sync.db, t.root, common.BytesToHash(segment.start)); err != nil {
 			return err
 		}
 	}