package vm import ( "errors" "fmt" "sort" "github.com/nspcc-dev/neo-go/pkg/core/interop/interopnames" "github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag" "github.com/nspcc-dev/neo-go/pkg/vm/stackitem" ) // interopIDFuncPrice adds an ID to the InteropFuncPrice. type interopIDFuncPrice struct { ID uint32 Func func(vm *VM) error Price int64 RequiredFlags callflag.CallFlag } var defaultVMInterops = []interopIDFuncPrice{ {ID: interopnames.ToID([]byte(interopnames.SystemRuntimeLog)), Func: runtimeLog, Price: 1 << 15, RequiredFlags: callflag.AllowNotify}, {ID: interopnames.ToID([]byte(interopnames.SystemRuntimeNotify)), Func: runtimeNotify, Price: 1 << 15, RequiredFlags: callflag.AllowNotify}, {ID: interopnames.ToID([]byte(interopnames.SystemIteratorCreate)), Func: IteratorCreate, Price: 1 << 4}, {ID: interopnames.ToID([]byte(interopnames.SystemIteratorNext)), Func: IteratorNext, Price: 1 << 15}, {ID: interopnames.ToID([]byte(interopnames.SystemIteratorValue)), Func: IteratorValue, Price: 1 << 4}, } func init() { sort.Slice(defaultVMInterops, func(i, j int) bool { return defaultVMInterops[i].ID < defaultVMInterops[j].ID }) } func defaultSyscallHandler(v *VM, id uint32) error { n := sort.Search(len(defaultVMInterops), func(i int) bool { return defaultVMInterops[i].ID >= id }) if n >= len(defaultVMInterops) || defaultVMInterops[n].ID != id { return errors.New("syscall not found") } d := defaultVMInterops[n] if !v.Context().callFlag.Has(d.RequiredFlags) { return fmt.Errorf("missing call flags: %05b vs %05b", v.Context().callFlag, d.RequiredFlags) } return d.Func(v) } // runtimeLog handles the syscall "System.Runtime.Log" for printing and logging stuff. func runtimeLog(vm *VM) error { msg := vm.Estack().Pop().String() fmt.Printf("NEO-GO-VM (log) > %s\n", msg) return nil } // runtimeNotify handles the syscall "System.Runtime.Notify" for printing and logging stuff. func runtimeNotify(vm *VM) error { name := vm.Estack().Pop().String() item := vm.Estack().Pop() fmt.Printf("NEO-GO-VM (notify) > [%s] %s\n", name, item.Value()) return nil } // init sorts the global defaultVMInterops value. func init() { sort.Slice(defaultVMInterops, func(i, j int) bool { return defaultVMInterops[i].ID < defaultVMInterops[j].ID }) } // IteratorNext handles syscall System.Enumerator.Next. func IteratorNext(v *VM) error { iop := v.Estack().Pop().Interop() arr := iop.Value().(iterator) v.Estack().PushVal(arr.Next()) return nil } // IteratorValue handles syscall System.Enumerator.Value. func IteratorValue(v *VM) error { iop := v.Estack().Pop().Interop() arr := iop.Value().(iterator) v.Estack().Push(&Element{value: arr.Value()}) return nil } // NewIterator creates new iterator from the provided stack item. func NewIterator(item stackitem.Item) (stackitem.Item, error) { switch t := item.(type) { case *stackitem.Array, *stackitem.Struct: return stackitem.NewInterop(&arrayWrapper{ index: -1, value: t.Value().([]stackitem.Item), }), nil case *stackitem.Map: return NewMapIterator(t), nil default: data, err := t.TryBytes() if err != nil { return nil, fmt.Errorf("non-iterable type %s", t.Type()) } return stackitem.NewInterop(&byteArrayWrapper{ index: -1, value: data, }), nil } } // IteratorCreate handles syscall System.Iterator.Create. func IteratorCreate(v *VM) error { data := v.Estack().Pop().Item() item, err := NewIterator(data) if err != nil { return err } v.Estack().Push(&Element{value: item}) return nil } // NewMapIterator returns new interop item containing iterator over m. func NewMapIterator(m *stackitem.Map) *stackitem.Interop { return stackitem.NewInterop(&mapWrapper{ index: -1, m: m.Value().([]stackitem.MapElement), }) }