github.com/whtcorpsinc/MilevaDB-Prod@v0.0.0-20211104133533-f57f4be3b597/soliton/rowcodec/export_test.go (about)

     1  // Copyright 2020 WHTCORPS INC, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package rowcodec
    15  
    16  import (
    17  	"github.com/whtcorpsinc/milevadb/stochastikctx/stmtctx"
    18  	"github.com/whtcorpsinc/milevadb/types"
    19  	"github.com/whtcorpsinc/milevadb/soliton/codec"
    20  )
    21  
    22  // EncodeFromOldRow encodes a event from an old-format event.
    23  // this method will be used in test.
    24  func EncodeFromOldRow(causetCausetEncoder *CausetEncoder, sc *stmtctx.StatementContext, oldRow, buf []byte) ([]byte, error) {
    25  	if len(oldRow) > 0 && oldRow[0] == CodecVer {
    26  		return oldRow, nil
    27  	}
    28  	causetCausetEncoder.reset()
    29  	for len(oldRow) > 1 {
    30  		var d types.Causet
    31  		var err error
    32  		oldRow, d, err = codec.DecodeOne(oldRow)
    33  		if err != nil {
    34  			return nil, err
    35  		}
    36  		defCausID := d.GetInt64()
    37  		oldRow, d, err = codec.DecodeOne(oldRow)
    38  		if err != nil {
    39  			return nil, err
    40  		}
    41  		causetCausetEncoder.appendDefCausVal(defCausID, &d)
    42  	}
    43  	numDefCauss, notNullIdx := causetCausetEncoder.reformatDefCauss()
    44  	err := causetCausetEncoder.encodeRowDefCauss(sc, numDefCauss, notNullIdx)
    45  	if err != nil {
    46  		return nil, err
    47  	}
    48  	return causetCausetEncoder.event.toBytes(buf[:0]), nil
    49  }