neoneo-go/pkg/core/interop/callback/method.go
2020-08-07 16:15:24 +03:00

60 lines
1.6 KiB
Go

package callback
import (
"errors"
"strings"
"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/smartcontract/manifest"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// MethodCallback represents callback for contract method.
type MethodCallback struct {
contract *state.Contract
method *manifest.Method
}
var _ Callback = (*MethodCallback)(nil)
// ArgCount implements Callback interface.
func (s *MethodCallback) ArgCount() int {
return len(s.method.Parameters)
}
// LoadContext implements Callback interface.
func (s *MethodCallback) LoadContext(v *vm.VM, args []stackitem.Item) {
v.Estack().PushVal(args)
v.Estack().PushVal(s.method.Name)
v.Estack().PushVal(s.contract.ScriptHash().BytesBE())
}
// CreateFromMethod creates callback for a contract method.
func CreateFromMethod(ic *interop.Context) error {
rawHash := ic.VM.Estack().Pop().Bytes()
h, err := util.Uint160DecodeBytesBE(rawHash)
if err != nil {
return err
}
cs, err := ic.DAO.GetContractState(h)
if err != nil {
return errors.New("contract not found")
}
method := string(ic.VM.Estack().Pop().Bytes())
if strings.HasPrefix(method, "_") {
return errors.New("invalid method name")
}
currCs, err := ic.DAO.GetContractState(ic.VM.GetCurrentScriptHash())
if err == nil && !currCs.Manifest.CanCall(&cs.Manifest, method) {
return errors.New("method call is not allowed")
}
md := cs.Manifest.ABI.GetMethod(method)
ic.VM.Estack().PushVal(stackitem.NewInterop(&MethodCallback{
contract: cs,
method: md,
}))
return nil
}