all: add read-only option to database (#22407)

* all: add read-only option to database

* all: fixes tests

* cmd/geth: migrate flags

* cmd/geth: fix the compact

* cmd/geth: fix the format

* cmd/geth: fix log

* cmd: add chain-readonly

* core: add readonly notion to freezer

* core/rawdb: add log

* core/rawdb: fix freezer close

* cmd: fix

* cmd, core: construct db

* core: update tests

cmd/geth/chaincmd.go

@@ -28,6 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/cmd/utils"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
@@ -191,7 +192,7 @@ func initGenesis(ctx *cli.Context) error {
 	defer stack.Close()
 
 	for _, name := range []string{"chaindata", "lightchaindata"} {
-		chaindb, err := stack.OpenDatabase(name, 0, 0, "")
+		chaindb, err := stack.OpenDatabase(name, 0, 0, "", false)
 		if err != nil {
 			utils.Fatalf("Failed to open database: %v", err)
 		}
@@ -229,7 +230,7 @@ func importChain(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, db := utils.MakeChain(ctx, stack, false)
+	chain, db := utils.MakeChain(ctx, stack)
 	defer db.Close()
 
 	// Start periodically gathering memory profiles
@@ -304,7 +305,7 @@ func exportChain(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, _ := utils.MakeChain(ctx, stack, true)
+	chain, _ := utils.MakeChain(ctx, stack)
 	start := time.Now()
 
 	var err error
@@ -340,7 +341,7 @@ func importPreimages(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	db := utils.MakeChainDatabase(ctx, stack)
+	db := utils.MakeChainDatabase(ctx, stack, false)
 	start := time.Now()
 
 	if err := utils.ImportPreimages(db, ctx.Args().First()); err != nil {
@@ -359,7 +360,7 @@ func exportPreimages(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	db := utils.MakeChainDatabase(ctx, stack)
+	db := utils.MakeChainDatabase(ctx, stack, true)
 	start := time.Now()
 
 	if err := utils.ExportPreimages(db, ctx.Args().First()); err != nil {
@@ -373,21 +374,27 @@ func dump(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, chainDb := utils.MakeChain(ctx, stack, true)
+	db := utils.MakeChainDatabase(ctx, stack, true)
-	defer chainDb.Close()
 	for _, arg := range ctx.Args() {
-		var block *types.Block
+		var header *types.Header
 		if hashish(arg) {
-			block = chain.GetBlockByHash(common.HexToHash(arg))
+			hash := common.HexToHash(arg)
+			number := rawdb.ReadHeaderNumber(db, hash)
+			if number != nil {
+				header = rawdb.ReadHeader(db, hash, *number)
+			}
 		} else {
-			num, _ := strconv.Atoi(arg)
+			number, _ := strconv.Atoi(arg)
-			block = chain.GetBlockByNumber(uint64(num))
+			hash := rawdb.ReadCanonicalHash(db, uint64(number))
+			if hash != (common.Hash{}) {
+				header = rawdb.ReadHeader(db, hash, uint64(number))
+			}
 		}
-		if block == nil {
+		if header == nil {
 			fmt.Println("{}")
 			utils.Fatalf("block not found")
 		} else {
-			state, err := state.New(block.Root(), state.NewDatabase(chainDb), nil)
+			state, err := state.New(header.Root, state.NewDatabase(db), nil)
 			if err != nil {
 				utils.Fatalf("could not create new state: %v", err)
 			}

cmd/geth/dao_test.go

@@ -123,7 +123,7 @@ func testDAOForkBlockNewChain(t *testing.T, test int, genesis string, expectBloc
 	}
 	// Retrieve the DAO config flag from the database
 	path := filepath.Join(datadir, "geth", "chaindata")
-	db, err := rawdb.NewLevelDBDatabase(path, 0, 0, "")
+	db, err := rawdb.NewLevelDBDatabase(path, 0, 0, "", false)
 	if err != nil {
 		t.Fatalf("test %d: failed to open test database: %v", test, err)
 	}

cmd/geth/dbcmd.go

@@ -28,9 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/console/prompt"
 	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/ethdb"
-	"github.com/ethereum/go-ethereum/ethdb/leveldb"
 	"github.com/ethereum/go-ethereum/log"
-	"github.com/syndtr/goleveldb/leveldb/opt"
 	"gopkg.in/urfave/cli.v1"
 )
 
@@ -65,43 +63,98 @@ Remove blockchain and state databases`,
 		Action:    utils.MigrateFlags(inspect),
 		Name:      "inspect",
 		ArgsUsage: "<prefix> <start>",
-
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+			utils.YoloV3Flag,
+		},
 		Usage:       "Inspect the storage size for each type of data in the database",
 		Description: `This commands iterates the entire database. If the optional 'prefix' and 'start' arguments are provided, then the iteration is limited to the given subset of data.`,
 	}
 	dbStatCmd = cli.Command{
-		Action: dbStats,
+		Action: utils.MigrateFlags(dbStats),
 		Name:   "stats",
 		Usage:  "Print leveldb statistics",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+			utils.YoloV3Flag,
+		},
 	}
 	dbCompactCmd = cli.Command{
-		Action: dbCompact,
+		Action: utils.MigrateFlags(dbCompact),
 		Name:   "compact",
 		Usage:  "Compact leveldb database. WARNING: May take a very long time",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+			utils.YoloV3Flag,
+			utils.CacheFlag,
+			utils.CacheDatabaseFlag,
+		},
 		Description: `This command performs a database compaction. 
 WARNING: This operation may take a very long time to finish, and may cause database
 corruption if it is aborted during execution'!`,
 	}
 	dbGetCmd = cli.Command{
-		Action:      dbGet,
+		Action:    utils.MigrateFlags(dbGet),
-		Name:        "get",
+		Name:      "get",
-		Usage:       "Show the value of a database key",
+		Usage:     "Show the value of a database key",
-		ArgsUsage:   "<hex-encoded key>",
+		ArgsUsage: "<hex-encoded key>",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+			utils.YoloV3Flag,
+		},
 		Description: "This command looks up the specified database key from the database.",
 	}
 	dbDeleteCmd = cli.Command{
-		Action:    dbDelete,
+		Action:    utils.MigrateFlags(dbDelete),
 		Name:      "delete",
 		Usage:     "Delete a database key (WARNING: may corrupt your database)",
 		ArgsUsage: "<hex-encoded key>",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+			utils.YoloV3Flag,
+		},
 		Description: `This command deletes the specified database key from the database. 
 WARNING: This is a low-level operation which may cause database corruption!`,
 	}
 	dbPutCmd = cli.Command{
-		Action:    dbPut,
+		Action:    utils.MigrateFlags(dbPut),
 		Name:      "put",
 		Usage:     "Set the value of a database key (WARNING: may corrupt your database)",
 		ArgsUsage: "<hex-encoded key> <hex-encoded value>",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+			utils.SyncModeFlag,
+			utils.MainnetFlag,
+			utils.RopstenFlag,
+			utils.RinkebyFlag,
+			utils.GoerliFlag,
+			utils.YoloV3Flag,
+		},
 		Description: `This command sets a given database key to the given value. 
 WARNING: This is a low-level operation which may cause database corruption!`,
 	}
@@ -192,10 +245,10 @@ func inspect(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	_, chainDb := utils.MakeChain(ctx, stack, true)
+	db := utils.MakeChainDatabase(ctx, stack, true)
-	defer chainDb.Close()
+	defer db.Close()
 
-	return rawdb.InspectDatabase(chainDb, prefix, start)
+	return rawdb.InspectDatabase(db, prefix, start)
 }
 
 func showLeveldbStats(db ethdb.Stater) {
@@ -214,48 +267,32 @@ func showLeveldbStats(db ethdb.Stater) {
 func dbStats(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
-	path := stack.ResolvePath("chaindata")
+
-	db, err := leveldb.NewCustom(path, "", func(options *opt.Options) {
+	db := utils.MakeChainDatabase(ctx, stack, true)
-		options.ReadOnly = true
+	defer db.Close()
-	})
+
-	if err != nil {
-		return err
-	}
 	showLeveldbStats(db)
-	err = db.Close()
-	if err != nil {
-		log.Info("Close err", "error", err)
-	}
 	return nil
 }
 
 func dbCompact(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
-	path := stack.ResolvePath("chaindata")
+
-	cache := ctx.GlobalInt(utils.CacheFlag.Name) * ctx.GlobalInt(utils.CacheDatabaseFlag.Name) / 100
+	db := utils.MakeChainDatabase(ctx, stack, false)
-	db, err := leveldb.NewCustom(path, "", func(options *opt.Options) {
+	defer db.Close()
-		options.OpenFilesCacheCapacity = utils.MakeDatabaseHandles()
+
-		options.BlockCacheCapacity = cache / 2 * opt.MiB
+	log.Info("Stats before compaction")
-		options.WriteBuffer = cache / 4 * opt.MiB // Two of these are used internally
-	})
-	if err != nil {
-		return err
-	}
 	showLeveldbStats(db)
+
 	log.Info("Triggering compaction")
-	err = db.Compact(nil, nil)
+	if err := db.Compact(nil, nil); err != nil {
-	if err != nil {
 		log.Info("Compact err", "error", err)
+		return err
 	}
+	log.Info("Stats after compaction")
 	showLeveldbStats(db)
-	log.Info("Closing db")
+	return nil
-	err = db.Close()
-	if err != nil {
-		log.Info("Close err", "error", err)
-	}
-	log.Info("Exiting")
-	return err
 }
 
 // dbGet shows the value of a given database key
@@ -265,14 +302,10 @@ func dbGet(ctx *cli.Context) error {
 	}
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
-	path := stack.ResolvePath("chaindata")
+
-	db, err := leveldb.NewCustom(path, "", func(options *opt.Options) {
+	db := utils.MakeChainDatabase(ctx, stack, true)
-		options.ReadOnly = true
-	})
-	if err != nil {
-		return err
-	}
 	defer db.Close()
+
 	key, err := hexutil.Decode(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
@@ -283,7 +316,7 @@ func dbGet(ctx *cli.Context) error {
 		log.Info("Get operation failed", "error", err)
 		return err
 	}
-	fmt.Printf("key %#x:\n\t%#x\n", key, data)
+	fmt.Printf("key %#x: %#x\n", key, data)
 	return nil
 }
 
@@ -294,13 +327,19 @@ func dbDelete(ctx *cli.Context) error {
 	}
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
-	db := utils.MakeChainDatabase(ctx, stack)
+
+	db := utils.MakeChainDatabase(ctx, stack, false)
 	defer db.Close()
+
 	key, err := hexutil.Decode(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
 	}
+	data, err := db.Get(key)
+	if err == nil {
+		fmt.Printf("Previous value: %#x\n", data)
+	}
 	if err = db.Delete(key); err != nil {
 		log.Info("Delete operation returned an error", "error", err)
 		return err
@@ -315,8 +354,10 @@ func dbPut(ctx *cli.Context) error {
 	}
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
-	db := utils.MakeChainDatabase(ctx, stack)
+
+	db := utils.MakeChainDatabase(ctx, stack, false)
 	defer db.Close()
+
 	var (
 		key   []byte
 		value []byte
@@ -335,7 +376,7 @@ func dbPut(ctx *cli.Context) error {
 	}
 	data, err = db.Get(key)
 	if err == nil {
-		fmt.Printf("Previous value:\n%#x\n", data)
+		fmt.Printf("Previous value: %#x\n", data)
 	}
 	return db.Put(key, value)
 }

cmd/geth/snapshot.go

@@ -152,10 +152,8 @@ func pruneState(ctx *cli.Context) error {
 	stack, config := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, chaindb := utils.MakeChain(ctx, stack, true)
+	chaindb := utils.MakeChainDatabase(ctx, stack, false)
-	defer chaindb.Close()
+	pruner, err := pruner.NewPruner(chaindb, stack.ResolvePath(""), stack.ResolvePath(config.Eth.TrieCleanCacheJournal), ctx.GlobalUint64(utils.BloomFilterSizeFlag.Name))
-
-	pruner, err := pruner.NewPruner(chaindb, chain.CurrentBlock().Header(), stack.ResolvePath(""), stack.ResolvePath(config.Eth.TrieCleanCacheJournal), ctx.GlobalUint64(utils.BloomFilterSizeFlag.Name))
 	if err != nil {
 		log.Error("Failed to open snapshot tree", "error", err)
 		return err
@@ -183,10 +181,13 @@ func verifyState(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, chaindb := utils.MakeChain(ctx, stack, true)
+	chaindb := utils.MakeChainDatabase(ctx, stack, true)
-	defer chaindb.Close()
+	headBlock := rawdb.ReadHeadBlock(chaindb)
-
+	if headBlock == nil {
-	snaptree, err := snapshot.New(chaindb, trie.NewDatabase(chaindb), 256, chain.CurrentBlock().Root(), false, false, false)
+		log.Error("Failed to load head block")
+		return errors.New("no head block")
+	}
+	snaptree, err := snapshot.New(chaindb, trie.NewDatabase(chaindb), 256, headBlock.Root(), false, false, false)
 	if err != nil {
 		log.Error("Failed to open snapshot tree", "error", err)
 		return err
@@ -195,7 +196,7 @@ func verifyState(ctx *cli.Context) error {
 		log.Error("Too many arguments given")
 		return errors.New("too many arguments")
 	}
-	var root = chain.CurrentBlock().Root()
+	var root = headBlock.Root()
 	if ctx.NArg() == 1 {
 		root, err = parseRoot(ctx.Args()[0])
 		if err != nil {
@@ -218,19 +219,16 @@ func traverseState(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, chaindb := utils.MakeChain(ctx, stack, true)
+	chaindb := utils.MakeChainDatabase(ctx, stack, true)
-	defer chaindb.Close()
+	headBlock := rawdb.ReadHeadBlock(chaindb)
-
+	if headBlock == nil {
+		log.Error("Failed to load head block")
+		return errors.New("no head block")
+	}
 	if ctx.NArg() > 1 {
 		log.Error("Too many arguments given")
 		return errors.New("too many arguments")
 	}
-	// Use the HEAD root as the default
-	head := chain.CurrentBlock()
-	if head == nil {
-		log.Error("Head block is missing")
-		return errors.New("head block is missing")
-	}
 	var (
 		root common.Hash
 		err  error
@@ -243,8 +241,8 @@ func traverseState(ctx *cli.Context) error {
 		}
 		log.Info("Start traversing the state", "root", root)
 	} else {
-		root = head.Root()
+		root = headBlock.Root()
-		log.Info("Start traversing the state", "root", root, "number", head.NumberU64())
+		log.Info("Start traversing the state", "root", root, "number", headBlock.NumberU64())
 	}
 	triedb := trie.NewDatabase(chaindb)
 	t, err := trie.NewSecure(root, triedb)
@@ -311,19 +309,16 @@ func traverseRawState(ctx *cli.Context) error {
 	stack, _ := makeConfigNode(ctx)
 	defer stack.Close()
 
-	chain, chaindb := utils.MakeChain(ctx, stack, true)
+	chaindb := utils.MakeChainDatabase(ctx, stack, true)
-	defer chaindb.Close()
+	headBlock := rawdb.ReadHeadBlock(chaindb)
-
+	if headBlock == nil {
+		log.Error("Failed to load head block")
+		return errors.New("no head block")
+	}
 	if ctx.NArg() > 1 {
 		log.Error("Too many arguments given")
 		return errors.New("too many arguments")
 	}
-	// Use the HEAD root as the default
-	head := chain.CurrentBlock()
-	if head == nil {
-		log.Error("Head block is missing")
-		return errors.New("head block is missing")
-	}
 	var (
 		root common.Hash
 		err  error
@@ -336,8 +331,8 @@ func traverseRawState(ctx *cli.Context) error {
 		}
 		log.Info("Start traversing the state", "root", root)
 	} else {
-		root = head.Root()
+		root = headBlock.Root()
-		log.Info("Start traversing the state", "root", root, "number", head.NumberU64())
+		log.Info("Start traversing the state", "root", root, "number", headBlock.NumberU64())
 	}
 	triedb := trie.NewDatabase(chaindb)
 	t, err := trie.NewSecure(root, triedb)

cmd/utils/flags.go

@@ -1628,7 +1628,7 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *ethconfig.Config) {
 		if ctx.GlobalIsSet(DataDirFlag.Name) {
 			// Check if we have an already initialized chain and fall back to
 			// that if so. Otherwise we need to generate a new genesis spec.
-			chaindb := MakeChainDatabase(ctx, stack)
+			chaindb := MakeChainDatabase(ctx, stack, true)
 			if rawdb.ReadCanonicalHash(chaindb, 0) != (common.Hash{}) {
 				cfg.Genesis = nil // fallback to db content
 			}
@@ -1749,7 +1749,7 @@ func SplitTagsFlag(tagsFlag string) map[string]string {
 }
 
 // MakeChainDatabase open an LevelDB using the flags passed to the client and will hard crash if it fails.
-func MakeChainDatabase(ctx *cli.Context, stack *node.Node) ethdb.Database {
+func MakeChainDatabase(ctx *cli.Context, stack *node.Node, readonly bool) ethdb.Database {
 	var (
 		cache   = ctx.GlobalInt(CacheFlag.Name) * ctx.GlobalInt(CacheDatabaseFlag.Name) / 100
 		handles = MakeDatabaseHandles()
@@ -1759,10 +1759,10 @@ func MakeChainDatabase(ctx *cli.Context, stack *node.Node) ethdb.Database {
 	)
 	if ctx.GlobalString(SyncModeFlag.Name) == "light" {
 		name := "lightchaindata"
-		chainDb, err = stack.OpenDatabase(name, cache, handles, "")
+		chainDb, err = stack.OpenDatabase(name, cache, handles, "", readonly)
 	} else {
 		name := "chaindata"
-		chainDb, err = stack.OpenDatabaseWithFreezer(name, cache, handles, ctx.GlobalString(AncientFlag.Name), "")
+		chainDb, err = stack.OpenDatabaseWithFreezer(name, cache, handles, ctx.GlobalString(AncientFlag.Name), "", readonly)
 	}
 	if err != nil {
 		Fatalf("Could not open database: %v", err)
@@ -1790,9 +1790,9 @@ func MakeGenesis(ctx *cli.Context) *core.Genesis {
 }
 
 // MakeChain creates a chain manager from set command line flags.
-func MakeChain(ctx *cli.Context, stack *node.Node, readOnly bool) (chain *core.BlockChain, chainDb ethdb.Database) {
+func MakeChain(ctx *cli.Context, stack *node.Node) (chain *core.BlockChain, chainDb ethdb.Database) {
 	var err error
-	chainDb = MakeChainDatabase(ctx, stack)
+	chainDb = MakeChainDatabase(ctx, stack, false) // TODO(rjl493456442) support read-only database
 	config, _, err := core.SetupGenesisBlock(chainDb, MakeGenesis(ctx))
 	if err != nil {
 		Fatalf("%v", err)
@@ -1841,12 +1841,10 @@ func MakeChain(ctx *cli.Context, stack *node.Node, readOnly bool) (chain *core.B
 		cache.TrieDirtyLimit = ctx.GlobalInt(CacheFlag.Name) * ctx.GlobalInt(CacheGCFlag.Name) / 100
 	}
 	vmcfg := vm.Config{EnablePreimageRecording: ctx.GlobalBool(VMEnableDebugFlag.Name)}
-	var limit *uint64
+
-	if ctx.GlobalIsSet(TxLookupLimitFlag.Name) && !readOnly {
+	// TODO(rjl493456442) disable snapshot generation/wiping if the chain is read only.
-		l := ctx.GlobalUint64(TxLookupLimitFlag.Name)
+	// Disable transaction indexing/unindexing by default.
-		limit = &l
+	chain, err = core.NewBlockChain(chainDb, cache, config, engine, vmcfg, nil, nil)
-	}
-	chain, err = core.NewBlockChain(chainDb, cache, config, engine, vmcfg, nil, limit)
 	if err != nil {
 		Fatalf("Can't create BlockChain: %v", err)
 	}

core/bench_test.go

@@ -157,7 +157,7 @@ func benchInsertChain(b *testing.B, disk bool, gen func(int, *BlockGen)) {
 			b.Fatalf("cannot create temporary directory: %v", err)
 		}
 		defer os.RemoveAll(dir)
-		db, err = rawdb.NewLevelDBDatabase(dir, 128, 128, "")
+		db, err = rawdb.NewLevelDBDatabase(dir, 128, 128, "", false)
 		if err != nil {
 			b.Fatalf("cannot create temporary database: %v", err)
 		}
@@ -255,7 +255,7 @@ func benchWriteChain(b *testing.B, full bool, count uint64) {
 		if err != nil {
 			b.Fatalf("cannot create temporary directory: %v", err)
 		}
-		db, err := rawdb.NewLevelDBDatabase(dir, 128, 1024, "")
+		db, err := rawdb.NewLevelDBDatabase(dir, 128, 1024, "", false)
 		if err != nil {
 			b.Fatalf("error opening database at %v: %v", dir, err)
 		}
@@ -272,7 +272,7 @@ func benchReadChain(b *testing.B, full bool, count uint64) {
 	}
 	defer os.RemoveAll(dir)
 
-	db, err := rawdb.NewLevelDBDatabase(dir, 128, 1024, "")
+	db, err := rawdb.NewLevelDBDatabase(dir, 128, 1024, "", false)
 	if err != nil {
 		b.Fatalf("error opening database at %v: %v", dir, err)
 	}
@@ -283,7 +283,7 @@ func benchReadChain(b *testing.B, full bool, count uint64) {
 	b.ResetTimer()
 
 	for i := 0; i < b.N; i++ {
-		db, err := rawdb.NewLevelDBDatabase(dir, 128, 1024, "")
+		db, err := rawdb.NewLevelDBDatabase(dir, 128, 1024, "", false)
 		if err != nil {
 			b.Fatalf("error opening database at %v: %v", dir, err)
 		}

core/blockchain_repair_test.go

@@ -1762,7 +1762,7 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 	}
 	os.RemoveAll(datadir)
 
-	db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "")
+	db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "", false)
 	if err != nil {
 		t.Fatalf("Failed to create persistent database: %v", err)
 	}
@@ -1817,7 +1817,7 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 	}
 	// Force run a freeze cycle
 	type freezer interface {
-		Freeze(threshold uint64)
+		Freeze(threshold uint64) error
 		Ancients() (uint64, error)
 	}
 	db.(freezer).Freeze(tt.freezeThreshold)
@@ -1830,7 +1830,7 @@ func testRepair(t *testing.T, tt *rewindTest, snapshots bool) {
 	db.Close()
 
 	// Start a new blockchain back up and see where the repait leads us
-	db, err = rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "")
+	db, err = rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "", false)
 	if err != nil {
 		t.Fatalf("Failed to reopen persistent database: %v", err)
 	}

core/blockchain_sethead_test.go

@@ -1961,7 +1961,7 @@ func testSetHead(t *testing.T, tt *rewindTest, snapshots bool) {
 	}
 	os.RemoveAll(datadir)
 
-	db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "")
+	db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "", false)
 	if err != nil {
 		t.Fatalf("Failed to create persistent database: %v", err)
 	}
@@ -2023,7 +2023,7 @@ func testSetHead(t *testing.T, tt *rewindTest, snapshots bool) {
 	}
 	// Force run a freeze cycle
 	type freezer interface {
-		Freeze(threshold uint64)
+		Freeze(threshold uint64) error
 		Ancients() (uint64, error)
 	}
 	db.(freezer).Freeze(tt.freezeThreshold)

core/blockchain_snapshot_test.go

@@ -65,7 +65,7 @@ func (basic *snapshotTestBasic) prepare(t *testing.T) (*BlockChain, []*types.Blo
 	}
 	os.RemoveAll(datadir)
 
-	db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "")
+	db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "", false)
 	if err != nil {
 		t.Fatalf("Failed to create persistent database: %v", err)
 	}
@@ -261,7 +261,7 @@ func (snaptest *crashSnapshotTest) test(t *testing.T) {
 	db.Close()
 
 	// Start a new blockchain back up and see where the repair leads us
-	newdb, err := rawdb.NewLevelDBDatabaseWithFreezer(snaptest.datadir, 0, 0, snaptest.datadir, "")
+	newdb, err := rawdb.NewLevelDBDatabaseWithFreezer(snaptest.datadir, 0, 0, snaptest.datadir, "", false)
 	if err != nil {
 		t.Fatalf("Failed to reopen persistent database: %v", err)
 	}

core/blockchain_test.go

@@ -651,7 +651,7 @@ func TestFastVsFullChains(t *testing.T) {
 		t.Fatalf("failed to create temp freezer dir: %v", err)
 	}
 	defer os.Remove(frdir)
-	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
@@ -725,7 +725,7 @@ func TestLightVsFastVsFullChainHeads(t *testing.T) {
 			t.Fatalf("failed to create temp freezer dir: %v", err)
 		}
 		defer os.Remove(dir)
-		db, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), dir, "")
+		db, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), dir, "", false)
 		if err != nil {
 			t.Fatalf("failed to create temp freezer db: %v", err)
 		}
@@ -1592,7 +1592,7 @@ func TestBlockchainRecovery(t *testing.T) {
 	}
 	defer os.Remove(frdir)
 
-	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
@@ -1649,7 +1649,7 @@ func TestIncompleteAncientReceiptChainInsertion(t *testing.T) {
 		t.Fatalf("failed to create temp freezer dir: %v", err)
 	}
 	defer os.Remove(frdir)
-	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
@@ -1848,7 +1848,7 @@ func testInsertKnownChainData(t *testing.T, typ string) {
 		t.Fatalf("failed to create temp freezer dir: %v", err)
 	}
 	defer os.Remove(dir)
-	chaindb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), dir, "")
+	chaindb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), dir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
@@ -2128,7 +2128,7 @@ func TestTransactionIndices(t *testing.T) {
 		t.Fatalf("failed to create temp freezer dir: %v", err)
 	}
 	defer os.Remove(frdir)
-	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
@@ -2156,7 +2156,7 @@ func TestTransactionIndices(t *testing.T) {
 	// Init block chain with external ancients, check all needed indices has been indexed.
 	limit := []uint64{0, 32, 64, 128}
 	for _, l := range limit {
-		ancientDb, err = rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+		ancientDb, err = rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 		if err != nil {
 			t.Fatalf("failed to create temp freezer db: %v", err)
 		}
@@ -2176,7 +2176,7 @@ func TestTransactionIndices(t *testing.T) {
 	}
 
 	// Reconstruct a block chain which only reserves HEAD-64 tx indices
-	ancientDb, err = rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+	ancientDb, err = rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}
@@ -2255,7 +2255,7 @@ func TestSkipStaleTxIndicesInFastSync(t *testing.T) {
 		t.Fatalf("failed to create temp freezer dir: %v", err)
 	}
 	defer os.Remove(frdir)
-	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "")
+	ancientDb, err := rawdb.NewDatabaseWithFreezer(rawdb.NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create temp freezer db: %v", err)
 	}

core/rawdb/accessors_chain.go

@@ -825,3 +825,29 @@ func FindCommonAncestor(db ethdb.Reader, a, b *types.Header) *types.Header {
 	}
 	return a
 }
+
+// ReadHeadHeader returns the current canonical head header.
+func ReadHeadHeader(db ethdb.Reader) *types.Header {
+	headHeaderHash := ReadHeadHeaderHash(db)
+	if headHeaderHash == (common.Hash{}) {
+		return nil
+	}
+	headHeaderNumber := ReadHeaderNumber(db, headHeaderHash)
+	if headHeaderNumber == nil {
+		return nil
+	}
+	return ReadHeader(db, headHeaderHash, *headHeaderNumber)
+}
+
+// ReadHeadHeader returns the current canonical head block.
+func ReadHeadBlock(db ethdb.Reader) *types.Block {
+	headBlockHash := ReadHeadBlockHash(db)
+	if headBlockHash == (common.Hash{}) {
+		return nil
+	}
+	headBlockNumber := ReadHeaderNumber(db, headBlockHash)
+	if headBlockNumber == nil {
+		return nil
+	}
+	return ReadBlock(db, headBlockHash, *headBlockNumber)
+}

core/rawdb/accessors_chain_test.go

@@ -440,7 +440,7 @@ func TestAncientStorage(t *testing.T) {
 	}
 	defer os.Remove(frdir)
 
-	db, err := NewDatabaseWithFreezer(NewMemoryDatabase(), frdir, "")
+	db, err := NewDatabaseWithFreezer(NewMemoryDatabase(), frdir, "", false)
 	if err != nil {
 		t.Fatalf("failed to create database with ancient backend")
 	}

core/rawdb/database.go

@@ -57,7 +57,10 @@ func (frdb *freezerdb) Close() error {
 // Freeze is a helper method used for external testing to trigger and block until
 // a freeze cycle completes, without having to sleep for a minute to trigger the
 // automatic background run.
-func (frdb *freezerdb) Freeze(threshold uint64) {
+func (frdb *freezerdb) Freeze(threshold uint64) error {
+	if frdb.AncientStore.(*freezer).readonly {
+		return errReadOnly
+	}
 	// Set the freezer threshold to a temporary value
 	defer func(old uint64) {
 		atomic.StoreUint64(&frdb.AncientStore.(*freezer).threshold, old)
@@ -68,6 +71,7 @@ func (frdb *freezerdb) Freeze(threshold uint64) {
 	trigger := make(chan struct{}, 1)
 	frdb.AncientStore.(*freezer).trigger <- trigger
 	<-trigger
+	return nil
 }
 
 // nofreezedb is a database wrapper that disables freezer data retrievals.
@@ -121,9 +125,9 @@ func NewDatabase(db ethdb.KeyValueStore) ethdb.Database {
 // NewDatabaseWithFreezer creates a high level database on top of a given key-
 // value data store with a freezer moving immutable chain segments into cold
 // storage.
-func NewDatabaseWithFreezer(db ethdb.KeyValueStore, freezer string, namespace string) (ethdb.Database, error) {
+func NewDatabaseWithFreezer(db ethdb.KeyValueStore, freezer string, namespace string, readonly bool) (ethdb.Database, error) {
 	// Create the idle freezer instance
-	frdb, err := newFreezer(freezer, namespace)
+	frdb, err := newFreezer(freezer, namespace, readonly)
 	if err != nil {
 		return nil, err
 	}
@@ -192,8 +196,9 @@ func NewDatabaseWithFreezer(db ethdb.KeyValueStore, freezer string, namespace st
 		}
 	}
 	// Freezer is consistent with the key-value database, permit combining the two
-	go frdb.freeze(db)
+	if !frdb.readonly {
-
+		go frdb.freeze(db)
+	}
 	return &freezerdb{
 		KeyValueStore: db,
 		AncientStore:  frdb,
@@ -215,8 +220,8 @@ func NewMemoryDatabaseWithCap(size int) ethdb.Database {
 
 // NewLevelDBDatabase creates a persistent key-value database without a freezer
 // moving immutable chain segments into cold storage.
-func NewLevelDBDatabase(file string, cache int, handles int, namespace string) (ethdb.Database, error) {
+func NewLevelDBDatabase(file string, cache int, handles int, namespace string, readonly bool) (ethdb.Database, error) {
-	db, err := leveldb.New(file, cache, handles, namespace)
+	db, err := leveldb.New(file, cache, handles, namespace, readonly)
 	if err != nil {
 		return nil, err
 	}
@@ -225,12 +230,12 @@ func NewLevelDBDatabase(file string, cache int, handles int, namespace string) (
 
 // NewLevelDBDatabaseWithFreezer creates a persistent key-value database with a
 // freezer moving immutable chain segments into cold storage.
-func NewLevelDBDatabaseWithFreezer(file string, cache int, handles int, freezer string, namespace string) (ethdb.Database, error) {
+func NewLevelDBDatabaseWithFreezer(file string, cache int, handles int, freezer string, namespace string, readonly bool) (ethdb.Database, error) {
-	kvdb, err := leveldb.New(file, cache, handles, namespace)
+	kvdb, err := leveldb.New(file, cache, handles, namespace, readonly)
 	if err != nil {
 		return nil, err
 	}
-	frdb, err := NewDatabaseWithFreezer(kvdb, freezer, namespace)
+	frdb, err := NewDatabaseWithFreezer(kvdb, freezer, namespace, readonly)
 	if err != nil {
 		kvdb.Close()
 		return nil, err

core/rawdb/freezer.go

@@ -35,6 +35,10 @@ import (
 )
 
 var (
+	// errReadOnly is returned if the freezer is opened in read only mode. All the
+	// mutations are disallowed.
+	errReadOnly = errors.New("read only")
+
 	// errUnknownTable is returned if the user attempts to read from a table that is
 	// not tracked by the freezer.
 	errUnknownTable = errors.New("unknown table")
@@ -73,6 +77,7 @@ type freezer struct {
 	frozen    uint64 // Number of blocks already frozen
 	threshold uint64 // Number of recent blocks not to freeze (params.FullImmutabilityThreshold apart from tests)
 
+	readonly     bool
 	tables       map[string]*freezerTable // Data tables for storing everything
 	instanceLock fileutil.Releaser        // File-system lock to prevent double opens
 
@@ -84,7 +89,7 @@ type freezer struct {
 
 // newFreezer creates a chain freezer that moves ancient chain data into
 // append-only flat file containers.
-func newFreezer(datadir string, namespace string) (*freezer, error) {
+func newFreezer(datadir string, namespace string, readonly bool) (*freezer, error) {
 	// Create the initial freezer object
 	var (
 		readMeter  = metrics.NewRegisteredMeter(namespace+"ancient/read", nil)
@@ -106,6 +111,7 @@ func newFreezer(datadir string, namespace string) (*freezer, error) {
 	}
 	// Open all the supported data tables
 	freezer := &freezer{
+		readonly:     readonly,
 		threshold:    params.FullImmutabilityThreshold,
 		tables:       make(map[string]*freezerTable),
 		instanceLock: lock,
@@ -130,7 +136,7 @@ func newFreezer(datadir string, namespace string) (*freezer, error) {
 		lock.Release()
 		return nil, err
 	}
-	log.Info("Opened ancient database", "database", datadir)
+	log.Info("Opened ancient database", "database", datadir, "readonly", readonly)
 	return freezer, nil
 }
 
@@ -138,7 +144,7 @@ func newFreezer(datadir string, namespace string) (*freezer, error) {
 func (f *freezer) Close() error {
 	var errs []error
 	f.closeOnce.Do(func() {
-		f.quit <- struct{}{}
+		close(f.quit)
 		for _, table := range f.tables {
 			if err := table.Close(); err != nil {
 				errs = append(errs, err)
@@ -191,6 +197,9 @@ func (f *freezer) AncientSize(kind string) (uint64, error) {
 // injection will be rejected. But if two injections with same number happen at
 // the same time, we can get into the trouble.
 func (f *freezer) AppendAncient(number uint64, hash, header, body, receipts, td []byte) (err error) {
+	if f.readonly {
+		return errReadOnly
+	}
 	// Ensure the binary blobs we are appending is continuous with freezer.
 	if atomic.LoadUint64(&f.frozen) != number {
 		return errOutOrderInsertion
@@ -233,6 +242,9 @@ func (f *freezer) AppendAncient(number uint64, hash, header, body, receipts, td
 
 // TruncateAncients discards any recent data above the provided threshold number.
 func (f *freezer) TruncateAncients(items uint64) error {
+	if f.readonly {
+		return errReadOnly
+	}
 	if atomic.LoadUint64(&f.frozen) <= items {
 		return nil
 	}

core/state/pruner/pruner.go

@@ -85,8 +85,12 @@ type Pruner struct {
 }
 
 // NewPruner creates the pruner instance.
-func NewPruner(db ethdb.Database, headHeader *types.Header, datadir, trieCachePath string, bloomSize uint64) (*Pruner, error) {
+func NewPruner(db ethdb.Database, datadir, trieCachePath string, bloomSize uint64) (*Pruner, error) {
-	snaptree, err := snapshot.New(db, trie.NewDatabase(db), 256, headHeader.Root, false, false, false)
+	headBlock := rawdb.ReadHeadBlock(db)
+	if headBlock == nil {
+		return nil, errors.New("Failed to load head block")
+	}
+	snaptree, err := snapshot.New(db, trie.NewDatabase(db), 256, headBlock.Root(), false, false, false)
 	if err != nil {
 		return nil, err // The relevant snapshot(s) might not exist
 	}
@@ -104,7 +108,7 @@ func NewPruner(db ethdb.Database, headHeader *types.Header, datadir, trieCachePa
 		stateBloom:    stateBloom,
 		datadir:       datadir,
 		trieCachePath: trieCachePath,
-		headHeader:    headHeader,
+		headHeader:    headBlock.Header(),
 		snaptree:      snaptree,
 	}, nil
 }
@@ -350,9 +354,9 @@ func RecoverPruning(datadir string, db ethdb.Database, trieCachePath string) err
 	if stateBloomPath == "" {
 		return nil // nothing to recover
 	}
-	headHeader, err := getHeadHeader(db)
+	headBlock := rawdb.ReadHeadBlock(db)
-	if err != nil {
+	if headBlock == nil {
-		return err
+		return errors.New("Failed to load head block")
 	}
 	// Initialize the snapshot tree in recovery mode to handle this special case:
 	// - Users run the `prune-state` command multiple times
@@ -362,7 +366,7 @@ func RecoverPruning(datadir string, db ethdb.Database, trieCachePath string) err
 	// - The state HEAD is rewound already because of multiple incomplete `prune-state`
 	// In this case, even the state HEAD is not exactly matched with snapshot, it
 	// still feasible to recover the pruning correctly.
-	snaptree, err := snapshot.New(db, trie.NewDatabase(db), 256, headHeader.Root, false, false, true)
+	snaptree, err := snapshot.New(db, trie.NewDatabase(db), 256, headBlock.Root(), false, false, true)
 	if err != nil {
 		return err // The relevant snapshot(s) might not exist
 	}
@@ -382,7 +386,7 @@ func RecoverPruning(datadir string, db ethdb.Database, trieCachePath string) err
 	// otherwise the dangling state will be left.
 	var (
 		found       bool
-		layers      = snaptree.Snapshots(headHeader.Root, 128, true)
+		layers      = snaptree.Snapshots(headBlock.Root(), 128, true)
 		middleRoots = make(map[common.Hash]struct{})
 	)
 	for _, layer := range layers {
@@ -506,22 +510,6 @@ func findBloomFilter(datadir string) (string, common.Hash, error) {
 	return stateBloomPath, stateBloomRoot, nil
 }
 
-func getHeadHeader(db ethdb.Database) (*types.Header, error) {
-	headHeaderHash := rawdb.ReadHeadBlockHash(db)
-	if headHeaderHash == (common.Hash{}) {
-		return nil, errors.New("empty head block hash")
-	}
-	headHeaderNumber := rawdb.ReadHeaderNumber(db, headHeaderHash)
-	if headHeaderNumber == nil {
-		return nil, errors.New("empty head block number")
-	}
-	headHeader := rawdb.ReadHeader(db, headHeaderHash, *headHeaderNumber)
-	if headHeader == nil {
-		return nil, errors.New("empty head header")
-	}
-	return headHeader, nil
-}
-
 const warningLog = `
 
 WARNING!

core/state/snapshot/disklayer_test.go

@@ -524,7 +524,7 @@ func TestDiskSeek(t *testing.T) {
 		t.Fatal(err)
 	} else {
 		defer os.RemoveAll(dir)
-		diskdb, err := leveldb.New(dir, 256, 0, "")
+		diskdb, err := leveldb.New(dir, 256, 0, "", false)
 		if err != nil {
 			t.Fatal(err)
 		}

eth/backend.go

@@ -122,7 +122,7 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 	log.Info("Allocated trie memory caches", "clean", common.StorageSize(config.TrieCleanCache)*1024*1024, "dirty", common.StorageSize(config.TrieDirtyCache)*1024*1024)
 
 	// Assemble the Ethereum object
-	chainDb, err := stack.OpenDatabaseWithFreezer("chaindata", config.DatabaseCache, config.DatabaseHandles, config.DatabaseFreezer, "eth/db/chaindata/")
+	chainDb, err := stack.OpenDatabaseWithFreezer("chaindata", config.DatabaseCache, config.DatabaseHandles, config.DatabaseFreezer, "eth/db/chaindata/", false)
 	if err != nil {
 		return nil, err
 	}

eth/filters/bench_test.go

@@ -65,7 +65,7 @@ func benchmarkBloomBits(b *testing.B, sectionSize uint64) {
 	benchDataDir := node.DefaultDataDir() + "/geth/chaindata"
 	b.Log("Running bloombits benchmark   section size:", sectionSize)
 
-	db, err := rawdb.NewLevelDBDatabase(benchDataDir, 128, 1024, "")
+	db, err := rawdb.NewLevelDBDatabase(benchDataDir, 128, 1024, "", false)
 	if err != nil {
 		b.Fatalf("error opening database at %v: %v", benchDataDir, err)
 	}
@@ -126,7 +126,7 @@ func benchmarkBloomBits(b *testing.B, sectionSize uint64) {
 	for i := 0; i < benchFilterCnt; i++ {
 		if i%20 == 0 {
 			db.Close()
-			db, _ = rawdb.NewLevelDBDatabase(benchDataDir, 128, 1024, "")
+			db, _ = rawdb.NewLevelDBDatabase(benchDataDir, 128, 1024, "", false)
 			backend = &testBackend{db: db, sections: cnt}
 		}
 		var addr common.Address
@@ -157,7 +157,7 @@ func clearBloomBits(db ethdb.Database) {
 func BenchmarkNoBloomBits(b *testing.B) {
 	benchDataDir := node.DefaultDataDir() + "/geth/chaindata"
 	b.Log("Running benchmark without bloombits")
-	db, err := rawdb.NewLevelDBDatabase(benchDataDir, 128, 1024, "")
+	db, err := rawdb.NewLevelDBDatabase(benchDataDir, 128, 1024, "", false)
 	if err != nil {
 		b.Fatalf("error opening database at %v: %v", benchDataDir, err)
 	}

eth/filters/filter_test.go

@@ -49,7 +49,7 @@ func BenchmarkFilters(b *testing.B) {
 	defer os.RemoveAll(dir)
 
 	var (
-		db, _   = rawdb.NewLevelDBDatabase(dir, 0, 0, "")
+		db, _   = rawdb.NewLevelDBDatabase(dir, 0, 0, "", false)
 		backend = &testBackend{db: db}
 		key1, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
 		addr1   = crypto.PubkeyToAddress(key1.PublicKey)
@@ -103,7 +103,7 @@ func TestFilters(t *testing.T) {
 	defer os.RemoveAll(dir)
 
 	var (
-		db, _   = rawdb.NewLevelDBDatabase(dir, 0, 0, "")
+		db, _   = rawdb.NewLevelDBDatabase(dir, 0, 0, "", false)
 		backend = &testBackend{db: db}
 		key1, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
 		addr    = crypto.PubkeyToAddress(key1.PublicKey)

eth/protocols/eth/protocol_test.go

@@ -178,7 +178,7 @@ func TestEth66Messages(t *testing.T) {
 	// init the receipts
 	{
 		receipts = []*types.Receipt{
-			&types.Receipt{
+			{
 				Status:            types.ReceiptStatusFailed,
 				CumulativeGasUsed: 1,
 				Logs: []*types.Log{

ethdb/leveldb/leveldb.go

@@ -83,7 +83,7 @@ type Database struct {
 
 // New returns a wrapped LevelDB object. The namespace is the prefix that the
 // metrics reporting should use for surfacing internal stats.
-func New(file string, cache int, handles int, namespace string) (*Database, error) {
+func New(file string, cache int, handles int, namespace string, readonly bool) (*Database, error) {
 	return NewCustom(file, namespace, func(options *opt.Options) {
 		// Ensure we have some minimal caching and file guarantees
 		if cache < minCache {
@@ -96,6 +96,9 @@ func New(file string, cache int, handles int, namespace string) (*Database, erro
 		options.OpenFilesCacheCapacity = handles
 		options.BlockCacheCapacity = cache / 2 * opt.MiB
 		options.WriteBuffer = cache / 4 * opt.MiB // Two of these are used internally
+		if readonly {
+			options.ReadOnly = true
+		}
 	})
 }
 

les/client.go

@@ -80,11 +80,11 @@ type LightEthereum struct {
 
 // New creates an instance of the light client.
 func New(stack *node.Node, config *ethconfig.Config) (*LightEthereum, error) {
-	chainDb, err := stack.OpenDatabase("lightchaindata", config.DatabaseCache, config.DatabaseHandles, "eth/db/chaindata/")
+	chainDb, err := stack.OpenDatabase("lightchaindata", config.DatabaseCache, config.DatabaseHandles, "eth/db/chaindata/", false)
 	if err != nil {
 		return nil, err
 	}
-	lesDb, err := stack.OpenDatabase("les.client", 0, 0, "eth/db/lesclient/")
+	lesDb, err := stack.OpenDatabase("les.client", 0, 0, "eth/db/lesclient/", false)
 	if err != nil {
 		return nil, err
 	}

les/server.go

@@ -87,7 +87,7 @@ type LesServer struct {
 }
 
 func NewLesServer(node *node.Node, e ethBackend, config *ethconfig.Config) (*LesServer, error) {
-	lesDb, err := node.OpenDatabase("les.server", 0, 0, "eth/db/lesserver/")
+	lesDb, err := node.OpenDatabase("les.server", 0, 0, "eth/db/lesserver/", false)
 	if err != nil {
 		return nil, err
 	}

node/node.go

@@ -547,7 +547,7 @@ func (n *Node) EventMux() *event.TypeMux {
 // OpenDatabase opens an existing database with the given name (or creates one if no
 // previous can be found) from within the node's instance directory. If the node is
 // ephemeral, a memory database is returned.
-func (n *Node) OpenDatabase(name string, cache, handles int, namespace string) (ethdb.Database, error) {
+func (n *Node) OpenDatabase(name string, cache, handles int, namespace string, readonly bool) (ethdb.Database, error) {
 	n.lock.Lock()
 	defer n.lock.Unlock()
 	if n.state == closedState {
@@ -559,7 +559,7 @@ func (n *Node) OpenDatabase(name string, cache, handles int, namespace string) (
 	if n.config.DataDir == "" {
 		db = rawdb.NewMemoryDatabase()
 	} else {
-		db, err = rawdb.NewLevelDBDatabase(n.ResolvePath(name), cache, handles, namespace)
+		db, err = rawdb.NewLevelDBDatabase(n.ResolvePath(name), cache, handles, namespace, readonly)
 	}
 
 	if err == nil {
@@ -573,7 +573,7 @@ func (n *Node) OpenDatabase(name string, cache, handles int, namespace string) (
 // also attaching a chain freezer to it that moves ancient chain data from the
 // database to immutable append-only files. If the node is an ephemeral one, a
 // memory database is returned.
-func (n *Node) OpenDatabaseWithFreezer(name string, cache, handles int, freezer, namespace string) (ethdb.Database, error) {
+func (n *Node) OpenDatabaseWithFreezer(name string, cache, handles int, freezer, namespace string, readonly bool) (ethdb.Database, error) {
 	n.lock.Lock()
 	defer n.lock.Unlock()
 	if n.state == closedState {
@@ -592,7 +592,7 @@ func (n *Node) OpenDatabaseWithFreezer(name string, cache, handles int, freezer,
 		case !filepath.IsAbs(freezer):
 			freezer = n.ResolvePath(freezer)
 		}
-		db, err = rawdb.NewLevelDBDatabaseWithFreezer(root, cache, handles, freezer, namespace)
+		db, err = rawdb.NewLevelDBDatabaseWithFreezer(root, cache, handles, freezer, namespace, readonly)
 	}
 
 	if err == nil {

node/node_test.go

@@ -158,7 +158,7 @@ func TestNodeCloseClosesDB(t *testing.T) {
 	stack, _ := New(testNodeConfig())
 	defer stack.Close()
 
-	db, err := stack.OpenDatabase("mydb", 0, 0, "")
+	db, err := stack.OpenDatabase("mydb", 0, 0, "", false)
 	if err != nil {
 		t.Fatal("can't open DB:", err)
 	}
@@ -181,7 +181,7 @@ func TestNodeOpenDatabaseFromLifecycleStart(t *testing.T) {
 	var err error
 	stack.RegisterLifecycle(&InstrumentedService{
 		startHook: func() {
-			db, err = stack.OpenDatabase("mydb", 0, 0, "")
+			db, err = stack.OpenDatabase("mydb", 0, 0, "", false)
 			if err != nil {
 				t.Fatal("can't open DB:", err)
 			}
@@ -202,7 +202,7 @@ func TestNodeOpenDatabaseFromLifecycleStop(t *testing.T) {
 
 	stack.RegisterLifecycle(&InstrumentedService{
 		stopHook: func() {
-			db, err := stack.OpenDatabase("mydb", 0, 0, "")
+			db, err := stack.OpenDatabase("mydb", 0, 0, "", false)
 			if err != nil {
 				t.Fatal("can't open DB:", err)
 			}

trie/trie_test.go

@@ -1060,7 +1060,7 @@ func tempDB() (string, *Database) {
 	if err != nil {
 		panic(fmt.Sprintf("can't create temporary directory: %v", err))
 	}
-	diskdb, err := leveldb.New(dir, 256, 0, "")
+	diskdb, err := leveldb.New(dir, 256, 0, "", false)
 	if err != nil {
 		panic(fmt.Sprintf("can't create temporary database: %v", err))
 	}