telebit/vendor/github.com/jcmturner/rpc/v2/ndr/rawbytes.go

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2020-06-03 06:18:04 +00:00
package ndr
import (
"errors"
"fmt"
"reflect"
"strconv"
)
// type MyBytes []byte
// implement RawBytes interface
const (
sizeMethod = "Size"
)
// RawBytes interface should be implemented if reading just a number of bytes from the NDR stream
type RawBytes interface {
Size(interface{}) int
}
func rawBytesSize(parent reflect.Value, v reflect.Value) (int, error) {
sf := v.MethodByName(sizeMethod)
if !sf.IsValid() {
return 0, fmt.Errorf("could not find a method called %s on the implementation of RawBytes", sizeMethod)
}
in := []reflect.Value{parent}
f := sf.Call(in)
if f[0].Kind() != reflect.Int {
return 0, errors.New("the RawBytes size function did not return an integer")
}
return int(f[0].Int()), nil
}
func addSizeToTag(parent reflect.Value, v reflect.Value, tag reflect.StructTag) (reflect.StructTag, error) {
size, err := rawBytesSize(parent, v)
if err != nil {
return tag, err
}
ndrTag := parseTags(tag)
ndrTag.Map["size"] = strconv.Itoa(size)
return ndrTag.StructTag(), nil
}
func (dec *Decoder) readRawBytes(v reflect.Value, tag reflect.StructTag) error {
ndrTag := parseTags(tag)
sizeStr, ok := ndrTag.Map["size"]
if !ok {
return errors.New("size tag not available")
}
size, err := strconv.Atoi(sizeStr)
if err != nil {
return fmt.Errorf("size not valid: %v", err)
}
b, err := dec.readBytes(size)
if err != nil {
return err
}
v.Set(reflect.ValueOf(b).Convert(v.Type()))
return nil
}