Ori Newman eef5f27a87
[NOD-1422] Implement GHOSTDAG (#950)
* [NOD-1422] Implement GHOSTDAG

* [NOD-1422] Rename bluest->findSelectedParent

* [NOD-1422] Remove preallocations from MergeSetBlues and add preallocation in candidateBluesAnticoneSizes

* [NOD-1422] Rename blockghostdagdata.go to ghostdag.go
2020-10-14 16:47:04 +03:00

59 lines
1.6 KiB
Go

package ghostdagmanager
import (
"github.com/kaspanet/kaspad/domain/consensus/model"
"sort"
)
func (gm *GHOSTDAGManager) mergeSet(selecteParent *model.DomainHash,
blockParents []*model.DomainHash) []*model.DomainHash {
mergeSetMap := make(map[model.DomainHash]struct{}, gm.k)
mergeSetSlice := make([]*model.DomainHash, 0, gm.k)
selectedParentPast := make(map[model.DomainHash]struct{})
queue := []*model.DomainHash{}
// Queueing all parents (other than the selected parent itself) for processing.
for _, parent := range blockParents {
if *parent == *selecteParent {
continue
}
mergeSetMap[*parent] = struct{}{}
mergeSetSlice = append(mergeSetSlice, parent)
queue = append(queue, parent)
}
for len(queue) > 0 {
var current *model.DomainHash
current, queue = queue[0], queue[1:]
// For each parent of the current block we check whether it is in the past of the selected parent. If not,
// we add the it to the resulting anticone-set and queue it for further processing.
currentParents := gm.dagTopologyManager.Parents(current)
for _, parent := range currentParents {
if _, ok := mergeSetMap[*parent]; ok {
continue
}
if _, ok := selectedParentPast[*parent]; ok {
continue
}
isAncestorOfSelectedParent := gm.dagTopologyManager.IsAncestorOf(parent, selecteParent)
if isAncestorOfSelectedParent {
selectedParentPast[*parent] = struct{}{}
continue
}
mergeSetMap[*parent] = struct{}{}
mergeSetSlice = append(mergeSetSlice, parent)
queue = append(queue, parent)
}
}
sort.Slice(mergeSetSlice, func(i, j int) bool {
return gm.less(mergeSetSlice[i], mergeSetSlice[j])
})
return mergeSetSlice
}