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1 files changed, 204 insertions, 0 deletions

diff --git a/core/rawdb/table.go b/core/rawdb/table.go
new file mode 100644
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--- /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 <http://www.gnu.org/licenses/>.
+
+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)
+}