failed to watch mysql

[PureLo]

Describe the bug
failed to watch mysql
To Reproduce
Steps to reproduce the behavior:

1. sudo ./kyanos watch mysql
2. See error

WARN[0006] Could not find PREPARE statement for this EXECUTE command. Query not decoded.  
WARN[0006] Unknown command -1.                                                                                                                                               
panic: runtime error: slice bounds out of range [1:0]

goroutine 29 [running]:
kyanos/agent/protocol/mysql.HandleStmtCloseRequest(0xc0003f7a78?, 0x942fc5?, 0x476058?)
/home/runner/work/kyanos/kyanos/agent/protocol/mysql/handler.go:432 +0x23a
kyanos/agent/protocol/mysql.(*MysqlParser).ProcessStmtClose(0xc000000000?, 0xc0004064c0, {0xc0000d62f0, 0x0, 0xd}, 0xc0003f7b00)
/home/runner/work/kyanos/kyanos/agent/protocol/mysql/handler.go:44 +0x3b
kyanos/agent/protocol/mysql.(*MysqlParser).processPackets(0xc000a4d2e0?, 0xc000a4d308?, {0xc0000d62f0?, 0x0?, 0xc000000000?})
/home/runner/work/kyanos/kyanos/agent/protocol/mysql/mysql.go:202 +0x285
kyanos/agent/protocol/mysql.(*MysqlParser).Match(0xc004b04100, 0xc000a4d2e0, 0xc000a4d308)
/home/runner/work/kyanos/kyanos/agent/protocol/mysql/mysql.go:68 +0xf3
kyanos/agent/conn.(*Connection4).OnSyscallEvent(0xc000a4d1e0, {0xc000f9a810?, 0x180d9de4c23e2203?, 0x0?}, 0xc0003d0850?, 0xc000182540)
/home/runner/work/kyanos/kyanos/agent/conn/conntrack.go:423 +0x10e
kyanos/agent/conn.(*Processor).run(0xc00013a3f0)
/home/runner/work/kyanos/kyanos/agent/conn/processor.go:259 +0x8fa
created by kyanos/agent/conn.InitProcessorManager in goroutine 1
/home/runner/work/kyanos/kyanos/agent/conn/processor.go:32 +0x157

Screenshots

Desktop (please complete the following information):

• OS:

Linux localhost.localdomain 3.10.0-1160.105.1.el7.x86_64 #1 SMP Thu Dec 7 15:39:45 UTC 2023 x86_64 x86_64 x86_64 GNU/Linu

• Version 1.4.0

Additional context
the panic code is here

func HandleStmtCloseRequest(reqPacket *MysqlPacket, prepareMap map[int]PreparedStatement, record *Record) ParseState {
	if len(reqPacket.msg) < 1+kStmtIDBytes {
		common.ProtocolParserLog.Warnln("Insufficient number of bytes for STMT_CLOSE")
		return Invalid
	}

	record.Req = &(*reqPacket)
	record.Req.(*MysqlPacket).msg = ""

	stmt_id, _ :=
		common.LEndianBytesToKInt[int32]([]byte(reqPacket.msg[kStmtIDStartOffset:]), kStmtIDBytes)
	_, ok := prepareMap[int(stmt_id)]
	if ok {
		delete(prepareMap, int(stmt_id))
	} else {
		common.ProtocolParserLog.Warnf("Could not find prepare statement for this close command [stmt_id=%d].", stmt_id)
	}
	return Success
}

也许这里是想值拷贝？

record.Req = &(*reqPacket)
record.Req.(*MysqlPacket).msg = ""

类似以下代码

tmp := *reqPacket
record.Req = &tmp 
record.Req.(*MysqlPacket).msg = ""

[hengyoush]

Thank you for your feedback. I will take a look.