33 lines
651 B
Go
33 lines
651 B
Go
package message
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/binary"
|
|
"fmt"
|
|
|
|
"maunium.net/go/mautrix/crypto/olm"
|
|
)
|
|
|
|
type Decoder struct {
|
|
*bytes.Buffer
|
|
}
|
|
|
|
func NewDecoder(buf []byte) *Decoder {
|
|
return &Decoder{bytes.NewBuffer(buf)}
|
|
}
|
|
|
|
func (d *Decoder) ReadVarInt() (uint64, error) {
|
|
return binary.ReadUvarint(d)
|
|
}
|
|
|
|
func (d *Decoder) ReadVarBytes() ([]byte, error) {
|
|
if n, err := d.ReadVarInt(); err != nil {
|
|
return nil, err
|
|
} else if n > uint64(d.Len()) {
|
|
return nil, fmt.Errorf("%w: var bytes length says %d, but only %d bytes left", olm.ErrInputToSmall, n, d.Available())
|
|
} else {
|
|
out := make([]byte, n)
|
|
_, err = d.Read(out)
|
|
return out, err
|
|
}
|
|
}
|