From 4bf345225c8dc98004cc79b6d9dd88008c936dd3 Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <e.stratonikov@yadro.com>
Date: Tue, 20 Jun 2023 13:39:18 +0300
Subject: [PATCH] [#447] pilorama: Use named constant for the key size

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
---
 pkg/local_object_storage/pilorama/batch.go  |  7 +++----
 pkg/local_object_storage/pilorama/boltdb.go | 15 ++++++++++-----
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/pkg/local_object_storage/pilorama/batch.go b/pkg/local_object_storage/pilorama/batch.go
index bccd640f..c65488b7 100644
--- a/pkg/local_object_storage/pilorama/batch.go
+++ b/pkg/local_object_storage/pilorama/batch.go
@@ -64,7 +64,7 @@ func (b *batch) run() {
 		//    See TestForest_ApplySameOperation for details.
 		// 3. Parent of each operation is already in tree.
 		var parents map[uint64]struct{}
-		var cKey [17]byte
+		var cKey [maxKeySize]byte
 		var slow bool
 		for i := range b.operations {
 			_, _, _, inTree := b.forest.getState(bTree, stateKey(cKey[:], b.operations[i].Child))
@@ -75,7 +75,7 @@ func (b *batch) run() {
 
 			key := childrenKey(cKey[:], b.operations[i].Child, 0)
 			k, _ := bTree.Cursor().Seek(key)
-			if len(k) == 17 && binary.LittleEndian.Uint64(k[1:]) == b.operations[i].Child {
+			if len(k) == childrenKeySize && binary.LittleEndian.Uint64(k[1:]) == b.operations[i].Child {
 				slow = true
 				break
 			}
@@ -104,9 +104,8 @@ func (b *batch) run() {
 			return b.forest.applyOperation(bLog, bTree, b.operations, &lm)
 		}
 
-		var key [17]byte
 		for i := range b.operations {
-			if err := b.forest.do(bLog, bTree, key[:], b.operations[i]); err != nil {
+			if err := b.forest.do(bLog, bTree, cKey[:], b.operations[i]); err != nil {
 				return err
 			}
 		}
diff --git a/pkg/local_object_storage/pilorama/boltdb.go b/pkg/local_object_storage/pilorama/boltdb.go
index a1956113..53a52433 100644
--- a/pkg/local_object_storage/pilorama/boltdb.go
+++ b/pkg/local_object_storage/pilorama/boltdb.go
@@ -37,6 +37,11 @@ type boltForest struct {
 	cfg
 }
 
+const (
+	childrenKeySize = 17
+	maxKeySize      = childrenKeySize
+)
+
 var (
 	dataBucket = []byte{0}
 	logBucket  = []byte{1}
@@ -199,7 +204,7 @@ func (t *boltForest) TreeMove(ctx context.Context, d CIDDescriptor, treeID strin
 		if lm.Child == RootID {
 			lm.Child = t.findSpareID(bTree)
 		}
-		return t.do(bLog, bTree, make([]byte, 17), &lm)
+		return t.do(bLog, bTree, make([]byte, maxKeySize), &lm)
 	}))
 }
 
@@ -395,7 +400,7 @@ func (t *boltForest) addByPathInternal(d CIDDescriptor, attr string, treeID stri
 	}
 
 	var lm []Move
-	var key [17]byte
+	var key [maxKeySize]byte
 
 	fullID := bucketName(d.CID, treeID)
 	err := t.db.Batch(func(tx *bbolt.Tx) error {
@@ -612,7 +617,7 @@ func (t *boltForest) getTreeBuckets(tx *bbolt.Tx, treeRoot []byte) (*bbolt.Bucke
 // applyOperations applies log operations. Assumes lm are sorted by timestamp.
 func (t *boltForest) applyOperation(logBucket, treeBucket *bbolt.Bucket, ms []*Move, lm *Move) error {
 	var tmp Move
-	var cKey [17]byte
+	var cKey [maxKeySize]byte
 
 	c := logBucket.Cursor()
 
@@ -961,7 +966,7 @@ func (t *boltForest) TreeGetChildren(ctx context.Context, cid cidSDK.ID, treeID
 
 		b := treeRoot.Bucket(dataBucket)
 		c := b.Cursor()
-		for k, _ := c.Seek(key); len(k) == 17 && binary.LittleEndian.Uint64(k[1:]) == nodeID; k, _ = c.Next() {
+		for k, _ := c.Seek(key); len(k) == childrenKeySize && binary.LittleEndian.Uint64(k[1:]) == nodeID; k, _ = c.Next() {
 			children = append(children, binary.LittleEndian.Uint64(k[9:]))
 		}
 		return nil
@@ -1216,7 +1221,7 @@ func childrenKey(key []byte, child, parent Node) []byte {
 	key[0] = 'c'
 	binary.LittleEndian.PutUint64(key[1:], parent)
 	binary.LittleEndian.PutUint64(key[9:], child)
-	return key[:17]
+	return key[:childrenKeySize]
 }
 
 // 'i' + attribute name (string) + attribute value (string) + parent (id) + node (id) -> 0/1.