neo-go/pkg/vm/ref_counter.go

67 lines
1.4 KiB
Go
Raw Normal View History

package vm
import (
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// refCounter represents reference counter for the VM.
type refCounter struct {
items map[stackitem.Item]int
size int
}
func newRefCounter() *refCounter {
return &refCounter{
items: make(map[stackitem.Item]int),
}
}
// Add adds an item to the reference counter.
func (r *refCounter) Add(item stackitem.Item) {
r.size++
switch item.(type) {
case *stackitem.Array, *stackitem.Struct, *stackitem.Map:
if r.items[item]++; r.items[item] > 1 {
return
}
switch t := item.(type) {
case *stackitem.Array, *stackitem.Struct:
for _, it := range item.Value().([]stackitem.Item) {
r.Add(it)
}
case *stackitem.Map:
for i := range t.Value().([]stackitem.MapElement) {
r.Add(t.Value().([]stackitem.MapElement)[i].Value)
}
}
}
}
// Remove removes item from the reference counter.
func (r *refCounter) Remove(item stackitem.Item) {
r.size--
switch item.(type) {
case *stackitem.Array, *stackitem.Struct, *stackitem.Map:
if r.items[item] > 1 {
r.items[item]--
return
}
delete(r.items, item)
switch t := item.(type) {
case *stackitem.Array, *stackitem.Struct:
for _, it := range item.Value().([]stackitem.Item) {
r.Remove(it)
}
case *stackitem.Map:
for i := range t.Value().([]stackitem.MapElement) {
r.Remove(t.Value().([]stackitem.MapElement)[i].Value)
}
}
}
}