From d235e2c6a5788ec4a6cff15a16f56b38a3876a0d Mon Sep 17 00:00:00 2001 From: Determinant Date: Sun, 28 Jun 2020 14:47:41 -0400 Subject: ... --- accounts/abi/argument.go | 365 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 365 insertions(+) create mode 100644 accounts/abi/argument.go (limited to 'accounts/abi/argument.go') diff --git a/accounts/abi/argument.go b/accounts/abi/argument.go new file mode 100644 index 0000000..4dae586 --- /dev/null +++ b/accounts/abi/argument.go @@ -0,0 +1,365 @@ +// Copyright 2015 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package abi + +import ( + "encoding/json" + "fmt" + "reflect" + "strings" +) + +// Argument holds the name of the argument and the corresponding type. +// Types are used when packing and testing arguments. +type Argument struct { + Name string + Type Type + Indexed bool // indexed is only used by events +} + +type Arguments []Argument + +type ArgumentMarshaling struct { + Name string + Type string + Components []ArgumentMarshaling + Indexed bool +} + +// UnmarshalJSON implements json.Unmarshaler interface +func (argument *Argument) UnmarshalJSON(data []byte) error { + var arg ArgumentMarshaling + err := json.Unmarshal(data, &arg) + if err != nil { + return fmt.Errorf("argument json err: %v", err) + } + + argument.Type, err = NewType(arg.Type, arg.Components) + if err != nil { + return err + } + argument.Name = arg.Name + argument.Indexed = arg.Indexed + + return nil +} + +// LengthNonIndexed returns the number of arguments when not counting 'indexed' ones. Only events +// can ever have 'indexed' arguments, it should always be false on arguments for method input/output +func (arguments Arguments) LengthNonIndexed() int { + out := 0 + for _, arg := range arguments { + if !arg.Indexed { + out++ + } + } + return out +} + +// NonIndexed returns the arguments with indexed arguments filtered out +func (arguments Arguments) NonIndexed() Arguments { + var ret []Argument + for _, arg := range arguments { + if !arg.Indexed { + ret = append(ret, arg) + } + } + return ret +} + +// isTuple returns true for non-atomic constructs, like (uint,uint) or uint[] +func (arguments Arguments) isTuple() bool { + return len(arguments) > 1 +} + +// Unpack performs the operation hexdata -> Go format +func (arguments Arguments) Unpack(v interface{}, data []byte) error { + // make sure the passed value is arguments pointer + if reflect.Ptr != reflect.ValueOf(v).Kind() { + return fmt.Errorf("abi: Unpack(non-pointer %T)", v) + } + marshalledValues, err := arguments.UnpackValues(data) + if err != nil { + return err + } + if arguments.isTuple() { + return arguments.unpackTuple(v, marshalledValues) + } + return arguments.unpackAtomic(v, marshalledValues[0]) +} + +// UnpackIntoMap performs the operation hexdata -> mapping of argument name to argument value +func (arguments Arguments) UnpackIntoMap(v map[string]interface{}, data []byte) error { + marshalledValues, err := arguments.UnpackValues(data) + if err != nil { + return err + } + + return arguments.unpackIntoMap(v, marshalledValues) +} + +// unpack sets the unmarshalled value to go format. +// Note the dst here must be settable. +func unpack(t *Type, dst interface{}, src interface{}) error { + var ( + dstVal = reflect.ValueOf(dst).Elem() + srcVal = reflect.ValueOf(src) + ) + tuple, typ := false, t + for { + if typ.T == SliceTy || typ.T == ArrayTy { + typ = typ.Elem + continue + } + tuple = typ.T == TupleTy + break + } + if !tuple { + return set(dstVal, srcVal) + } + + // Dereferences interface or pointer wrapper + dstVal = indirectInterfaceOrPtr(dstVal) + + switch t.T { + case TupleTy: + if dstVal.Kind() != reflect.Struct { + return fmt.Errorf("abi: invalid dst value for unpack, want struct, got %s", dstVal.Kind()) + } + fieldmap, err := mapArgNamesToStructFields(t.TupleRawNames, dstVal) + if err != nil { + return err + } + for i, elem := range t.TupleElems { + fname := fieldmap[t.TupleRawNames[i]] + field := dstVal.FieldByName(fname) + if !field.IsValid() { + return fmt.Errorf("abi: field %s can't found in the given value", t.TupleRawNames[i]) + } + if err := unpack(elem, field.Addr().Interface(), srcVal.Field(i).Interface()); err != nil { + return err + } + } + return nil + case SliceTy: + if dstVal.Kind() != reflect.Slice { + return fmt.Errorf("abi: invalid dst value for unpack, want slice, got %s", dstVal.Kind()) + } + slice := reflect.MakeSlice(dstVal.Type(), srcVal.Len(), srcVal.Len()) + for i := 0; i < slice.Len(); i++ { + if err := unpack(t.Elem, slice.Index(i).Addr().Interface(), srcVal.Index(i).Interface()); err != nil { + return err + } + } + dstVal.Set(slice) + case ArrayTy: + if dstVal.Kind() != reflect.Array { + return fmt.Errorf("abi: invalid dst value for unpack, want array, got %s", dstVal.Kind()) + } + array := reflect.New(dstVal.Type()).Elem() + for i := 0; i < array.Len(); i++ { + if err := unpack(t.Elem, array.Index(i).Addr().Interface(), srcVal.Index(i).Interface()); err != nil { + return err + } + } + dstVal.Set(array) + } + return nil +} + +// unpackIntoMap unpacks marshalledValues into the provided map[string]interface{} +func (arguments Arguments) unpackIntoMap(v map[string]interface{}, marshalledValues []interface{}) error { + // Make sure map is not nil + if v == nil { + return fmt.Errorf("abi: cannot unpack into a nil map") + } + + for i, arg := range arguments.NonIndexed() { + v[arg.Name] = marshalledValues[i] + } + return nil +} + +// unpackAtomic unpacks ( hexdata -> go ) a single value +func (arguments Arguments) unpackAtomic(v interface{}, marshalledValues interface{}) error { + if arguments.LengthNonIndexed() == 0 { + return nil + } + argument := arguments.NonIndexed()[0] + elem := reflect.ValueOf(v).Elem() + + if elem.Kind() == reflect.Struct && argument.Type.T != TupleTy { + fieldmap, err := mapArgNamesToStructFields([]string{argument.Name}, elem) + if err != nil { + return err + } + field := elem.FieldByName(fieldmap[argument.Name]) + if !field.IsValid() { + return fmt.Errorf("abi: field %s can't be found in the given value", argument.Name) + } + return unpack(&argument.Type, field.Addr().Interface(), marshalledValues) + } + return unpack(&argument.Type, elem.Addr().Interface(), marshalledValues) +} + +// unpackTuple unpacks ( hexdata -> go ) a batch of values. +func (arguments Arguments) unpackTuple(v interface{}, marshalledValues []interface{}) error { + var ( + value = reflect.ValueOf(v).Elem() + typ = value.Type() + kind = value.Kind() + ) + if err := requireUnpackKind(value, typ, kind, arguments); err != nil { + return err + } + + // If the interface is a struct, get of abi->struct_field mapping + var abi2struct map[string]string + if kind == reflect.Struct { + var ( + argNames []string + err error + ) + for _, arg := range arguments.NonIndexed() { + argNames = append(argNames, arg.Name) + } + abi2struct, err = mapArgNamesToStructFields(argNames, value) + if err != nil { + return err + } + } + for i, arg := range arguments.NonIndexed() { + switch kind { + case reflect.Struct: + field := value.FieldByName(abi2struct[arg.Name]) + if !field.IsValid() { + return fmt.Errorf("abi: field %s can't be found in the given value", arg.Name) + } + if err := unpack(&arg.Type, field.Addr().Interface(), marshalledValues[i]); err != nil { + return err + } + case reflect.Slice, reflect.Array: + if value.Len() < i { + return fmt.Errorf("abi: insufficient number of arguments for unpack, want %d, got %d", len(arguments), value.Len()) + } + v := value.Index(i) + if err := requireAssignable(v, reflect.ValueOf(marshalledValues[i])); err != nil { + return err + } + if err := unpack(&arg.Type, v.Addr().Interface(), marshalledValues[i]); err != nil { + return err + } + default: + return fmt.Errorf("abi:[2] cannot unmarshal tuple in to %v", typ) + } + } + return nil + +} + +// UnpackValues can be used to unpack ABI-encoded hexdata according to the ABI-specification, +// without supplying a struct to unpack into. Instead, this method returns a list containing the +// values. An atomic argument will be a list with one element. +func (arguments Arguments) UnpackValues(data []byte) ([]interface{}, error) { + retval := make([]interface{}, 0, arguments.LengthNonIndexed()) + virtualArgs := 0 + for index, arg := range arguments.NonIndexed() { + marshalledValue, err := toGoType((index+virtualArgs)*32, arg.Type, data) + if arg.Type.T == ArrayTy && !isDynamicType(arg.Type) { + // If we have a static array, like [3]uint256, these are coded as + // just like uint256,uint256,uint256. + // This means that we need to add two 'virtual' arguments when + // we count the index from now on. + // + // Array values nested multiple levels deep are also encoded inline: + // [2][3]uint256: uint256,uint256,uint256,uint256,uint256,uint256 + // + // Calculate the full array size to get the correct offset for the next argument. + // Decrement it by 1, as the normal index increment is still applied. + virtualArgs += getTypeSize(arg.Type)/32 - 1 + } else if arg.Type.T == TupleTy && !isDynamicType(arg.Type) { + // If we have a static tuple, like (uint256, bool, uint256), these are + // coded as just like uint256,bool,uint256 + virtualArgs += getTypeSize(arg.Type)/32 - 1 + } + if err != nil { + return nil, err + } + retval = append(retval, marshalledValue) + } + return retval, nil +} + +// PackValues performs the operation Go format -> Hexdata +// It is the semantic opposite of UnpackValues +func (arguments Arguments) PackValues(args []interface{}) ([]byte, error) { + return arguments.Pack(args...) +} + +// Pack performs the operation Go format -> Hexdata +func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) { + // Make sure arguments match up and pack them + abiArgs := arguments + if len(args) != len(abiArgs) { + return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(abiArgs)) + } + // variable input is the output appended at the end of packed + // output. This is used for strings and bytes types input. + var variableInput []byte + + // input offset is the bytes offset for packed output + inputOffset := 0 + for _, abiArg := range abiArgs { + inputOffset += getTypeSize(abiArg.Type) + } + var ret []byte + for i, a := range args { + input := abiArgs[i] + // pack the input + packed, err := input.Type.pack(reflect.ValueOf(a)) + if err != nil { + return nil, err + } + // check for dynamic types + if isDynamicType(input.Type) { + // set the offset + ret = append(ret, packNum(reflect.ValueOf(inputOffset))...) + // calculate next offset + inputOffset += len(packed) + // append to variable input + variableInput = append(variableInput, packed...) + } else { + // append the packed value to the input + ret = append(ret, packed...) + } + } + // append the variable input at the end of the packed input + ret = append(ret, variableInput...) + + return ret, nil +} + +// ToCamelCase converts an under-score string to a camel-case string +func ToCamelCase(input string) string { + parts := strings.Split(input, "_") + for i, s := range parts { + if len(s) > 0 { + parts[i] = strings.ToUpper(s[:1]) + s[1:] + } + } + return strings.Join(parts, "") +} -- cgit v1.2.3