diff options
Diffstat (limited to 'accounts/abi/method.go')
-rw-r--r-- | accounts/abi/method.go | 162 |
1 files changed, 16 insertions, 146 deletions
diff --git a/accounts/abi/method.go b/accounts/abi/method.go index 66e8751f3..f434ffdbe 100644 --- a/accounts/abi/method.go +++ b/accounts/abi/method.go @@ -18,13 +18,12 @@ package abi import ( "fmt" - "reflect" "strings" "github.com/ethereum/go-ethereum/crypto" ) -// Callable method given a `Name` and whether the method is a constant. +// Method represents a callable given a `Name` and whether the method is a constant. // If the method is `Const` no transaction needs to be created for this // particular Method call. It can easily be simulated using a local VM. // For example a `Balance()` method only needs to retrieve something @@ -35,137 +34,8 @@ import ( type Method struct { Name string Const bool - Inputs []Argument - Outputs []Argument -} - -func (method Method) pack(args ...interface{}) ([]byte, error) { - // Make sure arguments match up and pack them - if len(args) != len(method.Inputs) { - return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(method.Inputs)) - } - // 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 _, input := range method.Inputs { - if input.Type.T == ArrayTy { - inputOffset += (32 * input.Type.Size) - } else { - inputOffset += 32 - } - } - - var ret []byte - for i, a := range args { - input := method.Inputs[i] - // pack the input - packed, err := input.Type.pack(reflect.ValueOf(a)) - if err != nil { - return nil, fmt.Errorf("`%s` %v", method.Name, err) - } - - // check for a slice type (string, bytes, slice) - if input.Type.requiresLengthPrefix() { - // calculate the offset - offset := inputOffset + len(variableInput) - - // set the offset - ret = append(ret, packNum(reflect.ValueOf(offset))...) - // Append the packed output to the variable input. The variable input - // will be appended at the end of the 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 -} - -// unpacks a method return tuple into a struct of corresponding go types -// -// Unpacking can be done into a struct or a slice/array. -func (method Method) tupleUnpack(v interface{}, output []byte) error { - // make sure the passed value is a pointer - valueOf := reflect.ValueOf(v) - if reflect.Ptr != valueOf.Kind() { - return fmt.Errorf("abi: Unpack(non-pointer %T)", v) - } - - var ( - value = valueOf.Elem() - typ = value.Type() - ) - - j := 0 - for i := 0; i < len(method.Outputs); i++ { - toUnpack := method.Outputs[i] - marshalledValue, err := toGoType((i+j)*32, toUnpack.Type, output) - if err != nil { - return err - } - if toUnpack.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 += toUnpack.Type.Size - 1 - } - reflectValue := reflect.ValueOf(marshalledValue) - - switch value.Kind() { - case reflect.Struct: - for j := 0; j < typ.NumField(); j++ { - field := typ.Field(j) - // TODO read tags: `abi:"fieldName"` - if field.Name == strings.ToUpper(method.Outputs[i].Name[:1])+method.Outputs[i].Name[1:] { - if err := set(value.Field(j), reflectValue, method.Outputs[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(method.Outputs), value.Len()) - } - v := value.Index(i) - if v.Kind() != reflect.Ptr && v.Kind() != reflect.Interface { - return fmt.Errorf("abi: cannot unmarshal %v in to %v", v.Type(), reflectValue.Type()) - } - reflectValue := reflect.ValueOf(marshalledValue) - if err := set(v.Elem(), reflectValue, method.Outputs[i]); err != nil { - return err - } - default: - return fmt.Errorf("abi: cannot unmarshal tuple in to %v", typ) - } - } - return nil -} - -func (method Method) isTupleReturn() bool { return len(method.Outputs) > 1 } - -func (method Method) singleUnpack(v interface{}, output []byte) error { - // make sure the passed value is a pointer - valueOf := reflect.ValueOf(v) - if reflect.Ptr != valueOf.Kind() { - return fmt.Errorf("abi: Unpack(non-pointer %T)", v) - } - - value := valueOf.Elem() - - marshalledValue, err := toGoType(0, method.Outputs[0].Type, output) - if err != nil { - return err - } - if err := set(value, reflect.ValueOf(marshalledValue), method.Outputs[0]); err != nil { - return err - } - return nil + Inputs Arguments + Outputs Arguments } // Sig returns the methods string signature according to the ABI spec. @@ -175,35 +45,35 @@ func (method Method) singleUnpack(v interface{}, output []byte) error { // function foo(uint32 a, int b) = "foo(uint32,int256)" // // Please note that "int" is substitute for its canonical representation "int256" -func (m Method) Sig() string { - types := make([]string, len(m.Inputs)) +func (method Method) Sig() string { + types := make([]string, len(method.Inputs)) i := 0 - for _, input := range m.Inputs { + for _, input := range method.Inputs { types[i] = input.Type.String() i++ } - return fmt.Sprintf("%v(%v)", m.Name, strings.Join(types, ",")) + return fmt.Sprintf("%v(%v)", method.Name, strings.Join(types, ",")) } -func (m Method) String() string { - inputs := make([]string, len(m.Inputs)) - for i, input := range m.Inputs { +func (method Method) String() string { + inputs := make([]string, len(method.Inputs)) + for i, input := range method.Inputs { inputs[i] = fmt.Sprintf("%v %v", input.Name, input.Type) } - outputs := make([]string, len(m.Outputs)) - for i, output := range m.Outputs { + outputs := make([]string, len(method.Outputs)) + for i, output := range method.Outputs { if len(output.Name) > 0 { outputs[i] = fmt.Sprintf("%v ", output.Name) } outputs[i] += output.Type.String() } constant := "" - if m.Const { + if method.Const { constant = "constant " } - return fmt.Sprintf("function %v(%v) %sreturns(%v)", m.Name, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", ")) + return fmt.Sprintf("function %v(%v) %sreturns(%v)", method.Name, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", ")) } -func (m Method) Id() []byte { - return crypto.Keccak256([]byte(m.Sig()))[:4] +func (method Method) Id() []byte { + return crypto.Keccak256([]byte(method.Sig()))[:4] } |