From d235e2c6a5788ec4a6cff15a16f56b38a3876a0d Mon Sep 17 00:00:00 2001 From: Determinant Date: Sun, 28 Jun 2020 14:47:41 -0400 Subject: ... --- core/rawdb/table.go | 204 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 204 insertions(+) create mode 100644 core/rawdb/table.go (limited to 'core/rawdb/table.go') diff --git a/core/rawdb/table.go b/core/rawdb/table.go new file mode 100644 index 0000000..f9078e8 --- /dev/null +++ b/core/rawdb/table.go @@ -0,0 +1,204 @@ +// Copyright 2018 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package rawdb + +import ( + "github.com/ava-labs/go-ethereum/ethdb" +) + +// table is a wrapper around a database that prefixes each key access with a pre- +// configured string. +type table struct { + db ethdb.Database + prefix string +} + +// NewTable returns a database object that prefixes all keys with a given string. +func NewTable(db ethdb.Database, prefix string) ethdb.Database { + return &table{ + db: db, + prefix: prefix, + } +} + +// Close is a noop to implement the Database interface. +func (t *table) Close() error { + return nil +} + +// Has retrieves if a prefixed version of a key is present in the database. +func (t *table) Has(key []byte) (bool, error) { + return t.db.Has(append([]byte(t.prefix), key...)) +} + +// Get retrieves the given prefixed key if it's present in the database. +func (t *table) Get(key []byte) ([]byte, error) { + return t.db.Get(append([]byte(t.prefix), key...)) +} + +// HasAncient is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) HasAncient(kind string, number uint64) (bool, error) { + return t.db.HasAncient(kind, number) +} + +// Ancient is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) Ancient(kind string, number uint64) ([]byte, error) { + return t.db.Ancient(kind, number) +} + +// Ancients is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) Ancients() (uint64, error) { + return t.db.Ancients() +} + +// AncientSize is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) AncientSize(kind string) (uint64, error) { + return t.db.AncientSize(kind) +} + +// AppendAncient is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) AppendAncient(number uint64, hash, header, body, receipts, td []byte) error { + return t.db.AppendAncient(number, hash, header, body, receipts, td) +} + +// TruncateAncients is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) TruncateAncients(items uint64) error { + return t.db.TruncateAncients(items) +} + +// Sync is a noop passthrough that just forwards the request to the underlying +// database. +func (t *table) Sync() error { + return t.db.Sync() +} + +// Put inserts the given value into the database at a prefixed version of the +// provided key. +func (t *table) Put(key []byte, value []byte) error { + return t.db.Put(append([]byte(t.prefix), key...), value) +} + +// Delete removes the given prefixed key from the database. +func (t *table) Delete(key []byte) error { + return t.db.Delete(append([]byte(t.prefix), key...)) +} + +// NewIterator creates a binary-alphabetical iterator over the entire keyspace +// contained within the database. +func (t *table) NewIterator() ethdb.Iterator { + return t.NewIteratorWithPrefix(nil) +} + +// NewIteratorWithStart creates a binary-alphabetical iterator over a subset of +// database content starting at a particular initial key (or after, if it does +// not exist). +func (t *table) NewIteratorWithStart(start []byte) ethdb.Iterator { + return t.db.NewIteratorWithStart(start) +} + +// NewIteratorWithPrefix creates a binary-alphabetical iterator over a subset +// of database content with a particular key prefix. +func (t *table) NewIteratorWithPrefix(prefix []byte) ethdb.Iterator { + return t.db.NewIteratorWithPrefix(append([]byte(t.prefix), prefix...)) +} + +// Stat returns a particular internal stat of the database. +func (t *table) Stat(property string) (string, error) { + return t.db.Stat(property) +} + +// Compact flattens the underlying data store for the given key range. In essence, +// deleted and overwritten versions are discarded, and the data is rearranged to +// reduce the cost of operations needed to access them. +// +// A nil start is treated as a key before all keys in the data store; a nil limit +// is treated as a key after all keys in the data store. If both is nil then it +// will compact entire data store. +func (t *table) Compact(start []byte, limit []byte) error { + // If no start was specified, use the table prefix as the first value + if start == nil { + start = []byte(t.prefix) + } + // If no limit was specified, use the first element not matching the prefix + // as the limit + if limit == nil { + limit = []byte(t.prefix) + for i := len(limit) - 1; i >= 0; i-- { + // Bump the current character, stopping if it doesn't overflow + limit[i]++ + if limit[i] > 0 { + break + } + // Character overflown, proceed to the next or nil if the last + if i == 0 { + limit = nil + } + } + } + // Range correctly calculated based on table prefix, delegate down + return t.db.Compact(start, limit) +} + +// NewBatch creates a write-only database that buffers changes to its host db +// until a final write is called, each operation prefixing all keys with the +// pre-configured string. +func (t *table) NewBatch() ethdb.Batch { + return &tableBatch{t.db.NewBatch(), t.prefix} +} + +// tableBatch is a wrapper around a database batch that prefixes each key access +// with a pre-configured string. +type tableBatch struct { + batch ethdb.Batch + prefix string +} + +// Put inserts the given value into the batch for later committing. +func (b *tableBatch) Put(key, value []byte) error { + return b.batch.Put(append([]byte(b.prefix), key...), value) +} + +// Delete inserts the a key removal into the batch for later committing. +func (b *tableBatch) Delete(key []byte) error { + return b.batch.Delete(append([]byte(b.prefix), key...)) +} + +// ValueSize retrieves the amount of data queued up for writing. +func (b *tableBatch) ValueSize() int { + return b.batch.ValueSize() +} + +// Write flushes any accumulated data to disk. +func (b *tableBatch) Write() error { + return b.batch.Write() +} + +// Reset resets the batch for reuse. +func (b *tableBatch) Reset() { + b.batch.Reset() +} + +// Replay replays the batch contents. +func (b *tableBatch) Replay(w ethdb.KeyValueWriter) error { + return b.batch.Replay(w) +} -- cgit v1.2.3-70-g09d2