gotosocial/vendor/github.com/vmihailenco/msgpack/v5/decode_map.go

340 lines
6.2 KiB
Go
Raw Normal View History

package msgpack
import (
"errors"
"fmt"
"reflect"
"github.com/vmihailenco/msgpack/v5/msgpcode"
)
var errArrayStruct = errors.New("msgpack: number of fields in array-encoded struct has changed")
var (
mapStringStringPtrType = reflect.TypeOf((*map[string]string)(nil))
mapStringStringType = mapStringStringPtrType.Elem()
)
var (
mapStringInterfacePtrType = reflect.TypeOf((*map[string]interface{})(nil))
mapStringInterfaceType = mapStringInterfacePtrType.Elem()
)
func decodeMapValue(d *Decoder, v reflect.Value) error {
n, err := d.DecodeMapLen()
if err != nil {
return err
}
typ := v.Type()
if n == -1 {
v.Set(reflect.Zero(typ))
return nil
}
if v.IsNil() {
v.Set(reflect.MakeMap(typ))
}
if n == 0 {
return nil
}
return d.decodeTypedMapValue(v, n)
}
func (d *Decoder) decodeMapDefault() (interface{}, error) {
if d.mapDecoder != nil {
return d.mapDecoder(d)
}
return d.DecodeMap()
}
// DecodeMapLen decodes map length. Length is -1 when map is nil.
func (d *Decoder) DecodeMapLen() (int, error) {
c, err := d.readCode()
if err != nil {
return 0, err
}
if msgpcode.IsExt(c) {
if err = d.skipExtHeader(c); err != nil {
return 0, err
}
c, err = d.readCode()
if err != nil {
return 0, err
}
}
return d.mapLen(c)
}
func (d *Decoder) mapLen(c byte) (int, error) {
if c == msgpcode.Nil {
return -1, nil
}
if c >= msgpcode.FixedMapLow && c <= msgpcode.FixedMapHigh {
return int(c & msgpcode.FixedMapMask), nil
}
if c == msgpcode.Map16 {
size, err := d.uint16()
return int(size), err
}
if c == msgpcode.Map32 {
size, err := d.uint32()
return int(size), err
}
return 0, unexpectedCodeError{code: c, hint: "map length"}
}
func decodeMapStringStringValue(d *Decoder, v reflect.Value) error {
mptr := v.Addr().Convert(mapStringStringPtrType).Interface().(*map[string]string)
return d.decodeMapStringStringPtr(mptr)
}
func (d *Decoder) decodeMapStringStringPtr(ptr *map[string]string) error {
size, err := d.DecodeMapLen()
if err != nil {
return err
}
if size == -1 {
*ptr = nil
return nil
}
m := *ptr
if m == nil {
*ptr = make(map[string]string, min(size, maxMapSize))
m = *ptr
}
for i := 0; i < size; i++ {
mk, err := d.DecodeString()
if err != nil {
return err
}
mv, err := d.DecodeString()
if err != nil {
return err
}
m[mk] = mv
}
return nil
}
func decodeMapStringInterfaceValue(d *Decoder, v reflect.Value) error {
ptr := v.Addr().Convert(mapStringInterfacePtrType).Interface().(*map[string]interface{})
return d.decodeMapStringInterfacePtr(ptr)
}
func (d *Decoder) decodeMapStringInterfacePtr(ptr *map[string]interface{}) error {
m, err := d.DecodeMap()
if err != nil {
return err
}
*ptr = m
return nil
}
func (d *Decoder) DecodeMap() (map[string]interface{}, error) {
n, err := d.DecodeMapLen()
if err != nil {
return nil, err
}
if n == -1 {
return nil, nil
}
m := make(map[string]interface{}, min(n, maxMapSize))
for i := 0; i < n; i++ {
mk, err := d.DecodeString()
if err != nil {
return nil, err
}
mv, err := d.decodeInterfaceCond()
if err != nil {
return nil, err
}
m[mk] = mv
}
return m, nil
}
func (d *Decoder) DecodeUntypedMap() (map[interface{}]interface{}, error) {
n, err := d.DecodeMapLen()
if err != nil {
return nil, err
}
if n == -1 {
return nil, nil
}
m := make(map[interface{}]interface{}, min(n, maxMapSize))
for i := 0; i < n; i++ {
mk, err := d.decodeInterfaceCond()
if err != nil {
return nil, err
}
mv, err := d.decodeInterfaceCond()
if err != nil {
return nil, err
}
m[mk] = mv
}
return m, nil
}
// DecodeTypedMap decodes a typed map. Typed map is a map that has a fixed type for keys and values.
// Key and value types may be different.
func (d *Decoder) DecodeTypedMap() (interface{}, error) {
n, err := d.DecodeMapLen()
if err != nil {
return nil, err
}
if n <= 0 {
return nil, nil
}
key, err := d.decodeInterfaceCond()
if err != nil {
return nil, err
}
value, err := d.decodeInterfaceCond()
if err != nil {
return nil, err
}
keyType := reflect.TypeOf(key)
valueType := reflect.TypeOf(value)
if !keyType.Comparable() {
return nil, fmt.Errorf("msgpack: unsupported map key: %s", keyType.String())
}
mapType := reflect.MapOf(keyType, valueType)
mapValue := reflect.MakeMap(mapType)
mapValue.SetMapIndex(reflect.ValueOf(key), reflect.ValueOf(value))
n--
if err := d.decodeTypedMapValue(mapValue, n); err != nil {
return nil, err
}
return mapValue.Interface(), nil
}
func (d *Decoder) decodeTypedMapValue(v reflect.Value, n int) error {
typ := v.Type()
keyType := typ.Key()
valueType := typ.Elem()
for i := 0; i < n; i++ {
mk := reflect.New(keyType).Elem()
if err := d.DecodeValue(mk); err != nil {
return err
}
mv := reflect.New(valueType).Elem()
if err := d.DecodeValue(mv); err != nil {
return err
}
v.SetMapIndex(mk, mv)
}
return nil
}
func (d *Decoder) skipMap(c byte) error {
n, err := d.mapLen(c)
if err != nil {
return err
}
for i := 0; i < n; i++ {
if err := d.Skip(); err != nil {
return err
}
if err := d.Skip(); err != nil {
return err
}
}
return nil
}
func decodeStructValue(d *Decoder, v reflect.Value) error {
c, err := d.readCode()
if err != nil {
return err
}
n, err := d.mapLen(c)
if err == nil {
return d.decodeStruct(v, n)
}
var err2 error
n, err2 = d.arrayLen(c)
if err2 != nil {
return err
}
if n <= 0 {
v.Set(reflect.Zero(v.Type()))
return nil
}
fields := structs.Fields(v.Type(), d.structTag)
if n != len(fields.List) {
return errArrayStruct
}
for _, f := range fields.List {
if err := f.DecodeValue(d, v); err != nil {
return err
}
}
return nil
}
func (d *Decoder) decodeStruct(v reflect.Value, n int) error {
if n == -1 {
v.Set(reflect.Zero(v.Type()))
return nil
}
fields := structs.Fields(v.Type(), d.structTag)
for i := 0; i < n; i++ {
name, err := d.decodeStringTemp()
if err != nil {
return err
}
if f := fields.Map[name]; f != nil {
if err := f.DecodeValue(d, v); err != nil {
return err
}
continue
}
if d.flags&disallowUnknownFieldsFlag != 0 {
return fmt.Errorf("msgpack: unknown field %q", name)
}
if err := d.Skip(); err != nil {
return err
}
}
return nil
}