fix PING on compressed connections

Author: methane

compress.go

@@ -113,12 +113,11 @@ func (c *compIO) readCompressedPacket() error{
 // Server may return error packet (e.g. 1153 Got a packet bigger than 'max_allowed_packet' bytes)
 // before receiving all packets from client. In this case, seqnr is younger than expected.
 // NOTE: Both of mariadbclient and mysqlclient do not check seqnr. Only server checks it.
-ifdebug&&compressionSequence!=c.mc.sequence{
+ifdebug&&compressionSequence!=c.mc.compressSequence{
 fmt.Printf("WARN: unexpected cmpress seq nr: expected %v, got %v",
-c.mc.sequence, compressionSequence)
+c.mc.compressSequence, compressionSequence)
  }
-c.mc.sequence=compressionSequence+1
-c.mc.compressSequence=c.mc.sequence
+c.mc.compressSequence=compressionSequence+1
 
 comprData, err:=c.mc.readNext(comprLength)
 iferr!=nil{
@@ -200,7 +199,7 @@ func (c *compIO) writeCompressedPacket(data []byte, uncompressedLen int) (int, e
 comprLength:=len(data) -7
 ifdebug{
 fmt.Printf(
-"writeCompressedPacket: comprLength=%v, uncompressedLen=%v, seq=%v",
+"writeCompressedPacket: comprLength=%v, uncompressedLen=%v, seq=%v\n",
 comprLength, uncompressedLen, mc.compressSequence)
  }
 

packets.go

@@ -17,6 +17,7 @@ import (
 "fmt"
 "io"
 "math"
+"os"
 "strconv"
 "time"
 )
@@ -62,26 +63,20 @@ func (mc *mysqlConn) readPacket() ([]byte, error){
 pktLen:=getUint24(data[:3])
 seq:=data[3]
 
-ifmc.compress{
+// check packet sync [8 bit]
+ifseq!=mc.sequence{
+mc.log(fmt.Sprintf("[warn] unexpected sequence nr: expected %v, got %v", mc.sequence, seq))
 // MySQL and MariaDB doesn't check packet nr in compressed packet.
-ifdebug&&seq!=mc.compressSequence{
-fmt.Printf("[debug] mismatched compression sequence nr: expected: %v, got %v",
-mc.compressSequence, seq)
- }
-mc.compressSequence=seq+1
- } else{
-// check packet sync [8 bit]
-ifseq!=mc.sequence{
-mc.log(fmt.Sprintf("[warn] unexpected seq nr: expected %v, got %v", mc.sequence, seq))
+if!mc.compress{
 // For large packets, we stop reading as soon as sync error.
 iflen(prevData) >0{
 mc.close()
 returnnil, ErrPktSyncMul
  }
 invalidSequence=true
  }
-mc.sequence++
  }
+mc.sequence=seq+1
 
 // packets with length 0 terminate a previous packet which is a
 // multiple of (2^24)-1 bytes long
@@ -146,7 +141,7 @@ func (mc *mysqlConn) writePacket(data []byte) error{
 
 // Write packet
 ifdebug{
-fmt.Printf("writePacket: size=%v seq=%v", size, mc.sequence)
+fmt.Fprintf(os.Stderr, "writePacket: size=%v seq=%v\n", size, mc.sequence)
  }
 
 n, err:=writeFunc(data[:4+size])
@@ -450,7 +445,9 @@ func (mc *mysqlConn) writeCommandPacket(command byte) error{
 data[4] =command
 
 // Send CMD packet
-returnmc.writePacket(data)
+err=mc.writePacket(data)
+mc.syncSequence()
+returnerr
 }
 
 func (mc*mysqlConn) writeCommandPacketStr(commandbyte, argstring) error{
@@ -491,7 +488,9 @@ func (mc *mysqlConn) writeCommandPacketUint32(command byte, arg uint32) error{
 binary.LittleEndian.PutUint32(data[5:], arg)
 
 // Send CMD packet
-returnmc.writePacket(data)
+err=mc.writePacket(data)
+mc.syncSequence()
+returnerr
 }
 
 /******************************************************************************
@@ -1018,7 +1017,6 @@ func (stmt *mysqlStmt) writeCommandLongData(paramID int, arg []byte) error{
 pktLen=dataOffset+argLen
  }
 
-stmt.mc.resetSequence()
 // Add command byte [1 byte]
 data[4] =comStmtSendLongData
 
@@ -1030,15 +1028,15 @@ func (stmt *mysqlStmt) writeCommandLongData(paramID int, arg []byte) error{
 
 // Send CMD packet
 err:=stmt.mc.writePacket(data[:4+pktLen])
+// Every COM_LONG_DATA packet reset Packet Sequence
+stmt.mc.resetSequence()
 iferr==nil{
 data=data[pktLen-dataOffset:]
 continue
  }
 returnerr
  }
 
-// Reset Packet Sequence
-stmt.mc.resetSequence()
 returnnil
 }