42 lines
1.7 KiB
Go
42 lines
1.7 KiB
Go
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// 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 ethdb
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type Snapshot interface {
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// Has retrieves if a key is present in the snapshot backing by a key-value
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// data store.
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Has(key []byte) (bool, error)
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// Get retrieves the given key if it's present in the snapshot backing by
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// key-value data store.
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Get(key []byte) ([]byte, error)
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// Release releases associated resources. Release should always succeed and can
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// be called multiple times without causing error.
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Release()
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}
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// Snapshotter wraps the Snapshot method of a backing data store.
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type Snapshotter interface {
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// NewSnapshot creates a database snapshot based on the current state.
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// The created snapshot will not be affected by all following mutations
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// happened on the database.
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// Note don't forget to release the snapshot once it's used up, otherwise
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// the stale data will never be cleaned up by the underlying compactor.
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NewSnapshot() (Snapshot, error)
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}
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