// Execute executes the code using the input as call data during the execution.
// It returns the EVM's return value, the new state and an error if it failed.
//
// Executes sets up a in memory, temporarily, environment for the execution of
// the given code. It enabled the JIT by default and make sure that it's restored
// to it's original state afterwards.
func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
if cfg == nil {
cfg = new(Config)
}
setDefaults(cfg)
// defer the call to setting back the original values
defer func(debug, forceJit, enableJit bool) {
vm.Debug = debug
vm.ForceJit = forceJit
vm.EnableJit = enableJit
}(vm.Debug, vm.ForceJit, vm.EnableJit)
vm.ForceJit = !cfg.DisableJit
vm.EnableJit = !cfg.DisableJit
vm.Debug = cfg.Debug
var (
db, _ = ethdb.NewMemDatabase()
statedb, _ = state.New(common.Hash{}, db)
vmenv = NewEnv(cfg, statedb)
sender = statedb.CreateAccount(cfg.Origin)
receiver = statedb.CreateAccount(common.StringToAddress("contract"))
)
// set the receiver's (the executing contract) code for execution.
receiver.SetCode(code)
// Call the code with the given configuration.
ret, err := vmenv.Call(
sender,
receiver.Address(),
input,
cfg.GasLimit,
cfg.GasPrice,
cfg.Value,
)
if cfg.Debug {
vm.StdErrFormat(vmenv.StructLogs())
}
return ret, statedb, err
}
// newCanonical creates a chain database, and injects a deterministic canonical
// chain. Depending on the full flag, if creates either a full block chain or a
// header only chain.
func newCanonical(n int, full bool) (ethdb.Database, *BlockChain, error) {
// Create te new chain database
db, _ := ethdb.NewMemDatabase()
evmux := &event.TypeMux{}
// Initialize a fresh chain with only a genesis block
genesis, _ := WriteTestNetGenesisBlock(db)
blockchain, _ := NewBlockChain(db, FakePow{}, evmux)
// Create and inject the requested chain
if n == 0 {
return db, blockchain, nil
}
if full {
// Full block-chain requested
blocks := makeBlockChain(genesis, n, db, canonicalSeed)
_, err := blockchain.InsertChain(blocks)
return db, blockchain, err
}
// Header-only chain requested
headers := makeHeaderChain(genesis.Header(), n, db, canonicalSeed)
_, err := blockchain.InsertHeaderChain(headers, 1)
return db, blockchain, err
}
// 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)
}