9 "github.com/anacrolix/missinggo/expect"
12 //----------------------------------------------------------------------------
14 //----------------------------------------------------------------------------
16 // In case if marshaler cannot encode a type, it will return this error. Typical
17 // example of such type is float32/float64 which has no bencode representation.
18 type MarshalTypeError struct {
22 func (e *MarshalTypeError) Error() string {
23 return "bencode: unsupported type: " + e.Type.String()
26 // Unmarshal argument must be a non-nil value of some pointer type.
27 type UnmarshalInvalidArgError struct {
31 func (e *UnmarshalInvalidArgError) Error() string {
33 return "bencode: Unmarshal(nil)"
36 if e.Type.Kind() != reflect.Ptr {
37 return "bencode: Unmarshal(non-pointer " + e.Type.String() + ")"
39 return "bencode: Unmarshal(nil " + e.Type.String() + ")"
42 // Unmarshaler spotted a value that was not appropriate for a given Go value.
43 type UnmarshalTypeError struct {
48 func (e *UnmarshalTypeError) Error() string {
49 return "bencode: value (" + e.Value + ") is not appropriate for type: " +
53 // Unmarshaler tried to write to an unexported (therefore unwritable) field.
54 type UnmarshalFieldError struct {
57 Field reflect.StructField
60 func (e *UnmarshalFieldError) Error() string {
61 return "bencode: key \"" + e.Key + "\" led to an unexported field \"" +
62 e.Field.Name + "\" in type: " + e.Type.String()
65 // Malformed bencode input, unmarshaler failed to parse it.
66 type SyntaxError struct {
67 Offset int64 // location of the error
68 What error // error description
71 func (e *SyntaxError) Error() string {
72 return fmt.Sprintf("bencode: syntax error (offset: %d): %s", e.Offset, e.What)
75 // A non-nil error was returned after calling MarshalBencode on a type which
76 // implements the Marshaler interface.
77 type MarshalerError struct {
82 func (e *MarshalerError) Error() string {
83 return "bencode: error calling MarshalBencode for type " + e.Type.String() + ": " + e.Err.Error()
86 // A non-nil error was returned after calling UnmarshalBencode on a type which
87 // implements the Unmarshaler interface.
88 type UnmarshalerError struct {
93 func (e *UnmarshalerError) Error() string {
94 return "bencode: error calling UnmarshalBencode for type " + e.Type.String() + ": " + e.Err.Error()
97 //----------------------------------------------------------------------------
99 //----------------------------------------------------------------------------
101 // Any type which implements this interface, will be marshaled using the
103 type Marshaler interface {
104 MarshalBencode() ([]byte, error)
107 // Any type which implements this interface, will be unmarshaled using the
109 type Unmarshaler interface {
110 UnmarshalBencode([]byte) error
113 // Marshal the value 'v' to the bencode form, return the result as []byte and
115 func Marshal(v interface{}) ([]byte, error) {
117 e := Encoder{w: &buf}
122 return buf.Bytes(), nil
125 func MustMarshal(v interface{}) []byte {
131 // Unmarshal the bencode value in the 'data' to a value pointed by the 'v'
132 // pointer, return a non-nil error if any.
133 func Unmarshal(data []byte, v interface{}) (err error) {
134 buf := bytes.NewBuffer(data)
137 if err == nil && buf.Len() != 0 {
138 err = ErrUnusedTrailingBytes{buf.Len()}
143 type ErrUnusedTrailingBytes struct {
147 func (me ErrUnusedTrailingBytes) Error() string {
148 return fmt.Sprintf("%d unused trailing bytes", me.NumUnusedBytes)
151 func NewDecoder(r io.Reader) *Decoder {
152 return &Decoder{r: &scanner{r: r}}
155 func NewEncoder(w io.Writer) *Encoder {
156 return &Encoder{w: w}