neoneo-go/pkg/core/storage_item.go
2019-12-06 12:16:55 +03:00

64 lines
1.8 KiB
Go

package core
import (
"github.com/CityOfZion/neo-go/pkg/core/storage"
"github.com/CityOfZion/neo-go/pkg/io"
"github.com/CityOfZion/neo-go/pkg/util"
)
// StorageItem is the value to be stored with read-only flag.
type StorageItem struct {
Value []byte
IsConst bool
}
// makeStorageItemKey returns a key used to store StorageItem in the DB.
func makeStorageItemKey(scripthash util.Uint160, key []byte) []byte {
return storage.AppendPrefix(storage.STStorage, append(scripthash.BytesLE(), key...))
}
// getStorageItemFromStore returns StorageItem if it exists in the given Store.
func getStorageItemFromStore(s storage.Store, scripthash util.Uint160, key []byte) *StorageItem {
b, err := s.Get(makeStorageItemKey(scripthash, key))
if err != nil {
return nil
}
r := io.NewBinReaderFromBuf(b)
si := &StorageItem{}
si.DecodeBinary(r)
if r.Err != nil {
return nil
}
return si
}
// putStorageItemIntoStore puts given StorageItem for given script with given
// key into the given Store.
func putStorageItemIntoStore(s storage.Store, scripthash util.Uint160, key []byte, si *StorageItem) error {
buf := io.NewBufBinWriter()
si.EncodeBinary(buf.BinWriter)
if buf.Err != nil {
return buf.Err
}
return s.Put(makeStorageItemKey(scripthash, key), buf.Bytes())
}
// deleteStorageItemInStore drops storage item for the given script with the
// given key from the Store.
func deleteStorageItemInStore(s storage.Store, scripthash util.Uint160, key []byte) error {
return s.Delete(makeStorageItemKey(scripthash, key))
}
// EncodeBinary implements Serializable interface.
func (si *StorageItem) EncodeBinary(w *io.BinWriter) {
w.WriteVarBytes(si.Value)
w.WriteLE(si.IsConst)
}
// DecodeBinary implements Serializable interface.
func (si *StorageItem) DecodeBinary(r *io.BinReader) {
si.Value = r.ReadBytes()
r.ReadLE(&si.IsConst)
}