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bocadillo/event_table_map.go

60 lines
1.6 KiB
Go

package blt
// TableMap ...
type TableMap struct {
TableID uint64
Flags uint16
SchemaName string
TableName string
ColumnCount uint64
ColumnTypes []byte
ColumnMeta []uint16
NullBitmask []byte
}
// Spec: https://dev.mysql.com/doc/internals/en/table-map-event.html
func (r *Reader) decodeTableMap(data []byte) TableMap {
buf := newReadBuffer(data)
var tm TableMap
idSize := r.format.tableIDSize(TableMapEvent)
if idSize == 6 {
tm.TableID = buf.readUint48()
} else {
tm.TableID = uint64(buf.readUint32())
}
tm.Flags = buf.readUint16()
tm.SchemaName = string(buf.readStringLenEnc())
buf.skip(1) // Always 0x00
tm.TableName = string(buf.readStringLenEnc())
buf.skip(1) // Always 0x00
tm.ColumnCount, _ = buf.readUintLenEnc()
tm.ColumnTypes = buf.readStringVarLen(int(tm.ColumnCount))
tm.ColumnMeta = decodeColumnMeta(buf.readStringLenEnc(), tm.ColumnTypes)
tm.NullBitmask = buf.readStringVarLen(int(tm.ColumnCount+8) / 7)
return tm
}
func decodeColumnMeta(data []byte, cols []byte) []uint16 {
pos := 0
meta := make([]uint16, len(cols))
for i, typ := range cols {
switch columnType(typ) {
case colTypeString, colTypeNewDecimal:
// TODO: Is that correct?
meta[i] = uint16(data[pos])<<8 | uint16(data[pos+1])
pos += 2
case colTypeVarchar, colTypeVarstring, colTypeBit:
// TODO: Is that correct?
meta[i] = decodeUint16(data[pos:])
pos += 2
case colTypeFloat, colTypeDouble, colTypeBlob, colTypeGeometry, colTypeJSON,
colTypeTime2, colTypeDatetime2, colTypeTimestamp2:
meta[i] = uint16(data[pos])
pos++
}
}
return meta
}