path: root/core/rawdb/schema.go

// 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 contains a collection of low level database accessors.
package rawdb

import (
    "encoding/binary"

    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/metrics"
)

// The fields below define the low level database schema prefixing.
var (
    // databaseVerisionKey tracks the current database version.
    databaseVerisionKey = []byte("DatabaseVersion")

    // headHeaderKey tracks the latest know header's hash.
    headHeaderKey = []byte("LastHeader")

    // headBlockKey tracks the latest know full block's hash.
    headBlockKey = []byte("LastBlock")

    // headFastBlockKey tracks the latest known incomplete block's hash during fast sync.
    headFastBlockKey = []byte("LastFast")

    // fastTrieProgressKey tracks the number of trie entries imported during fast sync.
    fastTrieProgressKey = []byte("TrieSync")

    // Data item prefixes (use single byte to avoid mixing data types, avoid `i`, used for indexes).
    headerPrefix       = []byte("h") // headerPrefix + num (uint64 big endian) + hash -> header
    headerTDSuffix     = []byte("t") // headerPrefix + num (uint64 big endian) + hash + headerTDSuffix -> td
    headerHashSuffix   = []byte("n") // headerPrefix + num (uint64 big endian) + headerHashSuffix -> hash
    headerNumberPrefix = []byte("H") // headerNumberPrefix + hash -> num (uint64 big endian)

    blockBodyPrefix     = []byte("b") // blockBodyPrefix + num (uint64 big endian) + hash -> block body
    blockReceiptsPrefix = []byte("r") // blockReceiptsPrefix + num (uint64 big endian) + hash -> block receipts

    txLookupPrefix  = []byte("l") // txLookupPrefix + hash -> transaction/receipt lookup metadata
    bloomBitsPrefix = []byte("B") // bloomBitsPrefix + bit (uint16 big endian) + section (uint64 big endian) + hash -> bloom bits

    preimagePrefix = []byte("secure-key-")      // preimagePrefix + hash -> preimage
    configPrefix   = []byte("ethereum-config-") // config prefix for the db

    // Chain index prefixes (use `i` + single byte to avoid mixing data types).
    BloomBitsIndexPrefix = []byte("iB") // BloomBitsIndexPrefix is the data table of a chain indexer to track its progress

    preimageCounter    = metrics.NewRegisteredCounter("db/preimage/total", nil)
    preimageHitCounter = metrics.NewRegisteredCounter("db/preimage/hits", nil)
)

// TxLookupEntry is a positional metadata to help looking up the data content of
// a transaction or receipt given only its hash.
type TxLookupEntry struct {
    BlockHash  common.Hash
    BlockIndex uint64
    Index      uint64
}

// encodeBlockNumber encodes a block number as big endian uint64
func encodeBlockNumber(number uint64) []byte {
    enc := make([]byte, 8)
    binary.BigEndian.PutUint64(enc, number)
    return enc
}

// headerKey = headerPrefix + num (uint64 big endian) + hash
func headerKey(number uint64, hash common.Hash) []byte {
    return append(append(headerPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
}

// headerTDKey = headerPrefix + num (uint64 big endian) + hash + headerTDSuffix
func headerTDKey(number uint64, hash common.Hash) []byte {
    return append(headerKey(number, hash), headerTDSuffix...)
}

// headerHashKey = headerPrefix + num (uint64 big endian) + headerHashSuffix
func headerHashKey(number uint64) []byte {
    return append(append(headerPrefix, encodeBlockNumber(number)...), headerHashSuffix...)
}

// headerNumberKey = headerNumberPrefix + hash
func headerNumberKey(hash common.Hash) []byte {
    return append(headerNumberPrefix, hash.Bytes()...)
}

// blockBodyKey = blockBodyPrefix + num (uint64 big endian) + hash
func blockBodyKey(number uint64, hash common.Hash) []byte {
    return append(append(blockBodyPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
}

// blockReceiptsKey = blockReceiptsPrefix + num (uint64 big endian) + hash
func blockReceiptsKey(number uint64, hash common.Hash) []byte {
    return append(append(blockReceiptsPrefix, encodeBlockNumber(number)...), hash.Bytes()...)
}

// txLookupKey = txLookupPrefix + hash
func txLookupKey(hash common.Hash) []byte {
    return append(txLookupPrefix, hash.Bytes()...)
}

// bloomBitsKey = bloomBitsPrefix + bit (uint16 big endian) + section (uint64 big endian) + hash
func bloomBitsKey(bit uint, section uint64, hash common.Hash) []byte {
    key := append(append(bloomBitsPrefix, make([]byte, 10)...), hash.Bytes()...)

    binary.BigEndian.PutUint16(key[1:], uint16(bit))
    binary.BigEndian.PutUint64(key[3:], section)

    return key
}

// preimageKey = preimagePrefix + hash
func preimageKey(hash common.Hash) []byte {
    return append(preimagePrefix, hash.Bytes()...)
}

// configKey = configPrefix + hash
func configKey(hash common.Hash) []byte {
    return append(configPrefix, hash.Bytes()...)
}