neoneo-go/pkg/core/interop/runtime/engine.go
Roman Khimov 0de949b575 stackitem: remove Item/StackItem from function names
They're useless in a package named 'stackitem', make this package a bit more
user-friendly.
2021-07-06 19:56:23 +03:00

120 lines
3.5 KiB
Go

package runtime
import (
"errors"
"fmt"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
"go.uber.org/zap"
)
const (
// MaxEventNameLen is the maximum length of a name for event.
MaxEventNameLen = 32
// MaxNotificationSize is the maximum length of a runtime log message.
MaxNotificationSize = 1024
)
// GetExecutingScriptHash returns executing script hash.
func GetExecutingScriptHash(ic *interop.Context) error {
return ic.VM.PushContextScriptHash(0)
}
// GetCallingScriptHash returns calling script hash.
// While Executing and Entry script hashes are always valid for non-native contracts,
// Calling hash is set explicitly when native contracts are used, because when switching from
// one native to another, no operations are performed on invocation stack.
func GetCallingScriptHash(ic *interop.Context) error {
h := ic.VM.GetCallingScriptHash()
ic.VM.Estack().PushVal(h.BytesBE())
return nil
}
// GetEntryScriptHash returns entry script hash.
func GetEntryScriptHash(ic *interop.Context) error {
return ic.VM.PushContextScriptHash(ic.VM.Istack().Len() - 1)
}
// Platform returns the name of the platform.
func Platform(ic *interop.Context) error {
ic.VM.Estack().PushVal([]byte("NEO"))
return nil
}
// GetTrigger returns the script trigger.
func GetTrigger(ic *interop.Context) error {
ic.VM.Estack().PushVal(byte(ic.Trigger))
return nil
}
// Notify should pass stack item to the notify plugin to handle it, but
// in neo-go the only meaningful thing to do here is to log.
func Notify(ic *interop.Context) error {
name := ic.VM.Estack().Pop().String()
elem := ic.VM.Estack().Pop()
args := elem.Array()
if len(name) > MaxEventNameLen {
return fmt.Errorf("event name must be less than %d", MaxEventNameLen)
}
// But it has to be serializable, otherwise we either have some broken
// (recursive) structure inside or an interop item that can't be used
// outside of the interop subsystem anyway.
bytes, err := stackitem.Serialize(elem.Item())
if err != nil {
return fmt.Errorf("bad notification: %w", err)
}
if len(bytes) > MaxNotificationSize {
return fmt.Errorf("notification size shouldn't exceed %d", MaxNotificationSize)
}
ne := state.NotificationEvent{
ScriptHash: ic.VM.GetCurrentScriptHash(),
Name: name,
Item: stackitem.DeepCopy(stackitem.NewArray(args)).(*stackitem.Array),
}
ic.Notifications = append(ic.Notifications, ne)
return nil
}
// Log logs the message passed.
func Log(ic *interop.Context) error {
state := ic.VM.Estack().Pop().String()
if len(state) > MaxNotificationSize {
return fmt.Errorf("message length shouldn't exceed %v", MaxNotificationSize)
}
var txHash string
if ic.Tx != nil {
txHash = ic.Tx.Hash().StringLE()
}
ic.Log.Info("runtime log",
zap.String("tx", txHash),
zap.String("script", ic.VM.GetCurrentScriptHash().StringLE()),
zap.String("msg", state))
return nil
}
// GetTime returns timestamp of the block being verified, or the latest
// one in the blockchain if no block is given to Context.
func GetTime(ic *interop.Context) error {
ic.VM.Estack().PushVal(ic.Block.Timestamp)
return nil
}
// BurnGas burns GAS to benefit NEO ecosystem.
func BurnGas(ic *interop.Context) error {
gas := ic.VM.Estack().Pop().BigInt()
if !gas.IsInt64() {
return errors.New("invalid GAS value")
}
g := gas.Int64()
if g <= 0 {
return errors.New("GAS must be positive")
}
if !ic.VM.AddGas(g) {
return errors.New("GAS limit exceeded")
}
return nil
}