72 lines
2.0 KiB
Go
72 lines
2.0 KiB
Go
// Copyright 2018 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package shed
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import (
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"github.com/ethereum/go-ethereum/rlp"
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"github.com/syndtr/goleveldb/leveldb"
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)
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// StructField is a helper to store complex structure by
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// encoding it in RLP format.
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type StructField struct {
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db *DB
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key []byte
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}
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// NewStructField returns a new StructField.
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// It validates its name and type against the database schema.
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func (db *DB) NewStructField(name string) (f StructField, err error) {
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key, err := db.schemaFieldKey(name, "struct-rlp")
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if err != nil {
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return f, err
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}
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return StructField{
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db: db,
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key: key,
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}, nil
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}
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// Get unmarshals data from the database to a provided val.
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// If the data is not found leveldb.ErrNotFound is returned.
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func (f StructField) Get(val interface{}) (err error) {
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b, err := f.db.Get(f.key)
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if err != nil {
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return err
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}
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return rlp.DecodeBytes(b, val)
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}
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// Put marshals provided val and saves it to the database.
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func (f StructField) Put(val interface{}) (err error) {
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b, err := rlp.EncodeToBytes(val)
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if err != nil {
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return err
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}
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return f.db.Put(f.key, b)
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}
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// PutInBatch marshals provided val and puts it into the batch.
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func (f StructField) PutInBatch(batch *leveldb.Batch, val interface{}) (err error) {
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b, err := rlp.EncodeToBytes(val)
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if err != nil {
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return err
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}
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batch.Put(f.key, b)
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return nil
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}
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