package state import ( "bytes" "io/ioutil" "sync" "time" . "github.com/tendermint/go-common" cfg "github.com/tendermint/go-config" dbm "github.com/tendermint/go-db" "github.com/tendermint/go-wire" "github.com/tendermint/tendermint/types" ) var ( stateKey = []byte("stateKey") ) //----------------------------------------------------------------------------- // NOTE: not goroutine-safe. type State struct { // mtx for writing to db mtx sync.Mutex db dbm.DB // should not change GenesisDoc *types.GenesisDoc ChainID string // updated at end of ExecBlock LastBlockHeight int // Genesis state has this set to 0. So, Block(H=0) does not exist. LastBlockID types.BlockID LastBlockTime time.Time Validators *types.ValidatorSet LastValidators *types.ValidatorSet // block.LastCommit validated against this // AppHash is updated after Commit; // it's stale after ExecBlock and before Commit Stale bool AppHash []byte valAddedOrRemoved bool // true if a validator was added or removed } func LoadState(db dbm.DB) *State { s := &State{db: db} buf := db.Get(stateKey) if len(buf) == 0 { return nil } else { r, n, err := bytes.NewReader(buf), new(int), new(error) wire.ReadBinaryPtr(&s, r, 0, n, err) if *err != nil { // DATA HAS BEEN CORRUPTED OR THE SPEC HAS CHANGED Exit(Fmt("Data has been corrupted or its spec has changed: %v\n", *err)) } // TODO: ensure that buf is completely read. } return s } func (s *State) Copy() *State { return &State{ db: s.db, GenesisDoc: s.GenesisDoc, ChainID: s.ChainID, LastBlockHeight: s.LastBlockHeight, LastBlockID: s.LastBlockID, LastBlockTime: s.LastBlockTime, Validators: s.Validators.Copy(), LastValidators: s.LastValidators.Copy(), Stale: s.Stale, // XXX: but really state shouldnt be copied while its stale AppHash: s.AppHash, } } func (s *State) Save() { s.mtx.Lock() defer s.mtx.Unlock() s.db.Set(stateKey, s.Bytes()) } func (s *State) Equals(s2 *State) bool { return bytes.Equal(s.Bytes(), s2.Bytes()) } func (s *State) Bytes() []byte { buf, n, err := new(bytes.Buffer), new(int), new(error) wire.WriteBinary(s, buf, n, err) if *err != nil { PanicCrisis(*err) } return buf.Bytes() } // Mutate state variables to match block and validators // Since we don't have the new AppHash yet, we set s.Stale=true func (s *State) SetBlockAndValidators(header *types.Header, blockPartsHeader types.PartSetHeader, prevValSet, nextValSet *types.ValidatorSet) { s.LastBlockHeight = header.Height s.LastBlockID = types.BlockID{header.Hash(), blockPartsHeader} s.LastBlockTime = header.Time s.Validators = nextValSet s.LastValidators = prevValSet s.Stale = true } func (s *State) ValidatorAddedOrRemoved() bool { return s.valAddedOrRemoved } func (s *State) GetValidators() (*types.ValidatorSet, *types.ValidatorSet) { return s.LastValidators, s.Validators } // Load the most recent state from "state" db, // or create a new one (and save) from genesis. func GetState(config cfg.Config, stateDB dbm.DB) *State { state := LoadState(stateDB) if state == nil { state = MakeGenesisStateFromFile(stateDB, config.GetString("genesis_file")) state.Save() } return state } //----------------------------------------------------------------------------- // Genesis func MakeGenesisStateFromFile(db dbm.DB, genDocFile string) *State { genDocJSON, err := ioutil.ReadFile(genDocFile) if err != nil { Exit(Fmt("Couldn't read GenesisDoc file: %v", err)) } genDoc := types.GenesisDocFromJSON(genDocJSON) return MakeGenesisState(db, genDoc) } func MakeGenesisState(db dbm.DB, genDoc *types.GenesisDoc) *State { if len(genDoc.Validators) == 0 { Exit(Fmt("The genesis file has no validators")) } if genDoc.GenesisTime.IsZero() { genDoc.GenesisTime = time.Now() } // Make validators slice validators := make([]*types.Validator, len(genDoc.Validators)) for i, val := range genDoc.Validators { pubKey := val.PubKey address := pubKey.Address() // Make validator validators[i] = &types.Validator{ Address: address, PubKey: pubKey, VotingPower: val.Amount, } } return &State{ db: db, GenesisDoc: genDoc, ChainID: genDoc.ChainID, LastBlockHeight: 0, LastBlockID: types.BlockID{}, LastBlockTime: genDoc.GenesisTime, Validators: types.NewValidatorSet(validators), LastValidators: types.NewValidatorSet(nil), AppHash: genDoc.AppHash, } }