// MakeChain creates a chain manager from set command line flags.
func MakeChain(ctx *cli.Context) (chain *core.BlockChain, chainDb ethdb.Database) {
datadir := MustMakeDataDir(ctx)
cache := ctx.GlobalInt(CacheFlag.Name)
var err error
if chainDb, err = ethdb.NewLDBDatabase(filepath.Join(datadir, "chaindata"), cache); err != nil {
Fatalf("Could not open database: %v", err)
}
if ctx.GlobalBool(OlympicFlag.Name) {
_, err := core.WriteTestNetGenesisBlock(chainDb)
if err != nil {
glog.Fatalln(err)
}
}
eventMux := new(event.TypeMux)
pow := ethash.New()
//genesis := core.GenesisBlock(uint64(ctx.GlobalInt(GenesisNonceFlag.Name)), blockDB)
chain, err = core.NewBlockChain(chainDb, pow, eventMux)
if err != nil {
Fatalf("Could not start chainmanager: %v", err)
}
return chain, chainDb
}
// OpenDatabase opens an existing database with the given name (or creates one
// if no previous can be found) from within the node's data directory. If the
// node is an ephemeral one, a memory database is returned.
func (ctx *ServiceContext) OpenDatabase(name string, cache int) (ethdb.Database, error) {
if ctx.datadir == "" {
return ethdb.NewMemDatabase()
}
return ethdb.NewLDBDatabase(filepath.Join(ctx.datadir, name), cache)
}