diff options
Diffstat (limited to 'accounts/abi/argument.go')
| -rw-r--r-- | accounts/abi/argument.go | 130 |
1 files changed, 80 insertions, 50 deletions
diff --git a/accounts/abi/argument.go b/accounts/abi/argument.go index 04ca6150a..1b480da60 100644 --- a/accounts/abi/argument.go +++ b/accounts/abi/argument.go @@ -67,6 +67,17 @@ func (arguments Arguments) LengthNonIndexed() int { 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 @@ -74,21 +85,25 @@ func (arguments Arguments) isTuple() bool { // Unpack performs the operation hexdata -> Go format func (arguments Arguments) Unpack(v interface{}, data []byte) error { - if arguments.isTuple() { - return arguments.unpackTuple(v, data) - } - return arguments.unpackAtomic(v, data) -} -func (arguments Arguments) unpackTuple(v interface{}, output []byte) error { // make sure the passed value is arguments pointer - valueOf := reflect.ValueOf(v) - if reflect.Ptr != valueOf.Kind() { + 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) +} + +func (arguments Arguments) unpackTuple(v interface{}, marshalledValues []interface{}) error { var ( - value = valueOf.Elem() + value = reflect.ValueOf(v).Elem() typ = value.Type() kind = value.Kind() ) @@ -110,30 +125,9 @@ func (arguments Arguments) unpackTuple(v interface{}, output []byte) error { exists[field] = true } } - // `i` counts the nonindexed arguments. - // `j` counts the number of complex types. - // both `i` and `j` are used to to correctly compute `data` offset. + for i, arg := range arguments.NonIndexed() { - i, j := -1, 0 - for _, arg := range arguments { - - if arg.Indexed { - // can't read, continue - continue - } - i++ - marshalledValue, err := toGoType((i+j)*32, arg.Type, output) - if err != nil { - return err - } - - if arg.Type.T == ArrayTy { - // combined index ('i' + 'j') need to be adjusted only by size of array, thus - // we need to decrement 'j' because 'i' was incremented - j += arg.Type.Size - 1 - } - - reflectValue := reflect.ValueOf(marshalledValue) + reflectValue := reflect.ValueOf(marshalledValues[i]) switch kind { case reflect.Struct: @@ -166,34 +160,72 @@ func (arguments Arguments) unpackTuple(v interface{}, output []byte) error { } // unpackAtomic unpacks ( hexdata -> go ) a single value -func (arguments Arguments) unpackAtomic(v interface{}, output []byte) error { - // make sure the passed value is arguments pointer - valueOf := reflect.ValueOf(v) - if reflect.Ptr != valueOf.Kind() { - return fmt.Errorf("abi: Unpack(non-pointer %T)", v) - } - arg := arguments[0] - if arg.Indexed { - return fmt.Errorf("abi: attempting to unpack indexed variable into element.") +func (arguments Arguments) unpackAtomic(v interface{}, marshalledValues []interface{}) error { + if len(marshalledValues) != 1 { + return fmt.Errorf("abi: wrong length, expected single value, got %d", len(marshalledValues)) } + elem := reflect.ValueOf(v).Elem() + reflectValue := reflect.ValueOf(marshalledValues[0]) + return set(elem, reflectValue, arguments.NonIndexed()[0]) +} - value := valueOf.Elem() +// Computes the full size of an array; +// i.e. counting nested arrays, which count towards size for unpacking. +func getArraySize(arr *Type) int { + size := arr.Size + // Arrays can be nested, with each element being the same size + arr = arr.Elem + for arr.T == ArrayTy { + // Keep multiplying by elem.Size while the elem is an array. + size *= arr.Size + arr = arr.Elem + } + // Now we have the full array size, including its children. + return size +} - marshalledValue, err := toGoType(0, arg.Type, output) - if err != nil { - return err +// 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 { + // 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 += getArraySize(&arg.Type) - 1 + } + if err != nil { + return nil, err + } + retval = append(retval, marshalledValue) } - return set(value, reflect.ValueOf(marshalledValue), arg) + return retval, nil } -// Unpack performs the operation Go format -> Hexdata +// 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 @@ -207,7 +239,6 @@ func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) { inputOffset += 32 } } - var ret []byte for i, a := range args { input := abiArgs[i] @@ -216,7 +247,6 @@ func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) { if err != nil { return nil, err } - // check for a slice type (string, bytes, slice) if input.Type.requiresLengthPrefix() { // calculate the offset |