Revert "edit" (#132)

[bytom/vapor.git] / protocol / state / blockindex.go

diff --git a/protocol/state/blockindex.go b/protocol/state/blockindex.go
index e2e1354..c2e3963 100644 (file)
--- a/protocol/state/blockindex.go
+++ b/protocol/state/blockindex.go
@@ -85,6 +85,20 @@ func (node *BlockNode) CalcPastMedianTime() uint64 {
        return timestamps[len(timestamps)/2]
 }
 
+// GetParent return the node of specified height
+// And the node satisfies the same chain as current node
+// Height of current node must greater than height parameter
+func (node *BlockNode) GetParent(height uint64) *BlockNode {
+       prevBlockNode := node
+       for prevBlockNode != nil && prevBlockNode.Height != height {
+               if prevBlockNode.Height < height {
+                       return nil
+               }
+               prevBlockNode = prevBlockNode.Parent
+       }
+       return prevBlockNode
+}
+
 // BlockIndex is the struct for help chain trace block chain as tree
 type BlockIndex struct {
        sync.RWMutex
@@ -97,9 +111,9 @@ type BlockIndex struct {
 // NewBlockIndex will create a empty BlockIndex
 func NewBlockIndex() *BlockIndex {
        return &BlockIndex{
-               index:       make(map[bc.Hash]*BlockNode),
+               index:     make(map[bc.Hash]*BlockNode),
                heightIndex: make(map[uint64][]*BlockNode),
-               mainChain:   make([]*BlockNode, 0, approxNodesPerDay),
+               mainChain: make([]*BlockNode, 0, approxNodesPerDay),
        }
 }