func (d *decoder) decode(rec *walpb.Record) error {
d.mu.Lock()
defer d.mu.Unlock()
rec.Reset()
l, err := readInt64(d.br)
if err != nil {
return err
}
data := make([]byte, l)
if _, err = io.ReadFull(d.br, data); err != nil {
// ReadFull returns io.EOF only if no bytes were read
// the decoder should treat this as an ErrUnexpectedEOF instead.
if err == io.EOF {
err = io.ErrUnexpectedEOF
}
return err
}
if err := rec.Unmarshal(data); err != nil {
return err
}
// skip crc checking if the record type is crcType
if rec.Type == crcType {
return nil
}
d.crc.Write(rec.Data)
return rec.Validate(d.crc.Sum32())
}
func (d *decoder) decodeRecord(rec *walpb.Record) error {
if len(d.brs) == 0 {
return io.EOF
}
l, err := readInt64(d.brs[0])
if err == io.EOF || (err == nil && l == 0) {
// hit end of file or preallocated space
d.brs = d.brs[1:]
if len(d.brs) == 0 {
return io.EOF
}
d.lastValidOff = 0
return d.decodeRecord(rec)
}
if err != nil {
return err
}
recBytes, padBytes := decodeFrameSize(l)
data := make([]byte, recBytes+padBytes)
if _, err = io.ReadFull(d.brs[0], data); err != nil {
// ReadFull returns io.EOF only if no bytes were read
// the decoder should treat this as an ErrUnexpectedEOF instead.
if err == io.EOF {
err = io.ErrUnexpectedEOF
}
return err
}
if err := rec.Unmarshal(data[:recBytes]); err != nil {
if d.isTornEntry(data) {
return io.ErrUnexpectedEOF
}
return err
}
// skip crc checking if the record type is crcType
if rec.Type != crcType {
d.crc.Write(rec.Data)
if err := rec.Validate(d.crc.Sum32()); err != nil {
if d.isTornEntry(data) {
return io.ErrUnexpectedEOF
}
return err
}
}
// record decoded as valid; point last valid offset to end of record
d.lastValidOff += recBytes + padBytes + 8
return nil
}
func (d *decoder) decode(rec *walpb.Record) error {
rec.Reset()
l, err := readInt64(d.br)
if err != nil {
return err
}
data := make([]byte, l)
if _, err = io.ReadFull(d.br, data); err != nil {
return err
}
if err := rec.Unmarshal(data); err != nil {
return err
}
// skip crc checking if the record type is crcType
if rec.Type == crcType {
return nil
}
d.crc.Write(rec.Data)
return rec.Validate(d.crc.Sum32())
}