package native import ( "errors" "fmt" "github.com/nspcc-dev/neo-go/pkg/core/interop" "github.com/nspcc-dev/neo-go/pkg/smartcontract" "github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger" "github.com/nspcc-dev/neo-go/pkg/vm/stackitem" ) // Call calls specified native contract method. func Call(ic *interop.Context) error { id := int32(ic.VM.Estack().Pop().BigInt().Int64()) var c interop.Contract for _, ctr := range ic.Natives { if ctr.Metadata().ContractID == id { c = ctr break } } if c == nil { return fmt.Errorf("native contract %d not found", id) } h := ic.VM.GetCurrentScriptHash() if !h.Equals(c.Metadata().Hash) { return errors.New("it is not allowed to use Neo.Native.Call directly to call native contracts. System.Contract.Call should be used") } operation := ic.VM.Estack().Pop().String() m, ok := c.Metadata().Methods[operation] if !ok { return fmt.Errorf("method %s not found", operation) } if !ic.VM.Context().GetCallFlags().Has(m.RequiredFlags) { return fmt.Errorf("missing call flags for native %d `%s` operation call: %05b vs %05b", id, operation, ic.VM.Context().GetCallFlags(), m.RequiredFlags) } // Native contract prices are not multiplied by `BaseExecFee`. if !ic.VM.AddGas(m.Price) { return errors.New("gas limit exceeded") } ctx := ic.VM.Context() args := make([]stackitem.Item, len(m.MD.Parameters)) for i := range args { args[i] = ic.VM.Estack().Pop().Item() } result := m.Func(ic, args) if m.MD.ReturnType != smartcontract.VoidType { ctx.Estack().PushVal(result) } return nil } // OnPersist calls OnPersist methods for all native contracts. func OnPersist(ic *interop.Context) error { if ic.Trigger != trigger.OnPersist { return errors.New("onPersist must be trigered by system") } for _, c := range ic.Natives { err := c.OnPersist(ic) if err != nil { return err } } return nil } // PostPersist calls PostPersist methods for all native contracts. func PostPersist(ic *interop.Context) error { if ic.Trigger != trigger.PostPersist { return errors.New("postPersist must be trigered by system") } for _, c := range ic.Natives { err := c.PostPersist(ic) if err != nil { return err } } return nil }